Bump the gem version to v0.5.0

Add full NIP-19 compatibility
note, nprofile, nevent, naddr, npub, nsec and nrelay
2023-11-20 21:05:36 +07:00 · 2023-11-20 21:03:24 +07:00 · 2023-11-20 12:39:58 +07:00 · 2023-11-20 10:42:32 +07:00 · 2023-11-20 10:32:27 +07:00 · 2023-11-20 09:59:27 +07:00
101 changed files with 3076 additions and 375 deletions
--- a/.editorconfig
+++ b/.editorconfig
@@ -6,6 +6,6 @@ max_line_length = 120
 trim_trailing_whitespace = true

 # 2 space indentation
-[*.rb]
+[{*.rb, *.mjs}]
 indent_style = space
 indent_size = 2
--- a/.gitignore
+++ b/.gitignore
@@ -18,3 +18,6 @@
 .env.test.local
 .env.production.local
 .env.local
+
+# A local copy of nostr nips to help Github Copilot suggestions
+/nips/
--- a/.rubocop.yml
+++ b/.rubocop.yml
@@ -9,8 +9,17 @@ AllCops:
  DisplayCopNames: true
  NewCops: enable

+# ----------------------- Gemspec -----------------------
+
+Gemspec/DevelopmentDependencies:
+  Enabled: false
+
 # ----------------------- Style -----------------------

+Style/RaiseArgs:
+  Exclude:
+    - 'lib/nostr/key.rb'
+
 Style/StringLiterals:
  Enabled: true
  EnforcedStyle: single_quotes
@@ -38,3 +47,17 @@ Metrics/ParameterLists:

 RSpec/ExampleLength:
  Enabled: false
+
+RSpec/FilePath:
+  Exclude:
+    - spec/nostr/errors/invalid_*
+
+RSpec/SpecFilePathFormat:
+  Exclude:
+    - spec/nostr/errors/invalid_*
+
+# ----------------------- Naming -----------------------
+
+Naming/MemoizedInstanceVariableName:
+  Exclude:
+    - 'spec/nostr/key.rb'
--- a/.tool-versions
+++ b/.tool-versions
@@ -1 +1,2 @@
-ruby 3.2.0
+ruby 3.2.2
+bun 1.0.11
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,9 +1,42 @@
 # Changelog
 All notable changes to this project will be documented in this file.

-The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.0.0/)
+The format is based on [Keep a Changelog](http://keepachangelog.com/en/1.1.1/)
 and this project adheres to [Semantic Versioning](http://semver.org/spec/v2.0.0.html).

+## [0.5.0] 2023-11-20
+
+### Added
+
+- Added relay message type enums `Nostr::RelayMessageType`
+- Compliance with [NIP-19](https://github.com/nostr-protocol/nips/blob/master/19.md) - bech32-formatted strings
+- `Nostr::PrivateKey` and `Nostr::PublicKey` to represent private and public keys, respectively
+- Added a validation of private and public keys
+- Added an ability to convert keys to and from Bech32 format
+- Added RBS types for `faye-websocket` and `bech32`
+
+### Changed
+
+- Set the gem's homepage to [`https://nostr-ruby.com/`](https://nostr-ruby.com/)
+- Updated the filter's documentation to reflect the removal of prefix matching
+- Updated the subscription's id documentation to reflect the changes in the protocol definition
+- Updated `Nostr::PrivateKey` and `Nostr::PublicKey` internally, instead of Strings
+- Updated the gem `bip-schnorr` to version `0.6` (was `0.4`)
+- Updated the gem `puma` to version `6.4` (was `6.3`)
+- Updated the gem `rake` to version `13.1` (was `13.0`)
+- Updated the gem `rbs` to version `3.3` (was `2.8`)
+- Updated the gem `rubocop` to version `1.57` (was `1.42`)
+- Updated the gem `rubocop-rspec` to version `2.25` (was `2.16`)
+- Updated the gem `steep` to version `1.6` (was `1.4`)
+
+## Fixed
+
+- Fixed the RBS type of the constant `Nostr::Crypto::BN_BASE`
+- Fixed the return type of `Nostr::Crypto#decrypt_text` when given an invalid ciphertext
+- Fixed the RBS type of `Nostr::Filter#to_h`, `Nostr::Filter#e` and `Nostr::Filter#p`
+- Fixed the RBS types of `EventEmitter` and `EventMachine::Channel`
+- Fixed the generation of private keys
+
 ## [0.4.0] - 2023-02-25

 ### Removed
@@ -49,6 +82,7 @@ principles of immutability and was a major source of internal complexity as I ne

 - Initial release

+[0.5.0]: https://github.com/wilsonsilva/nostr/compare/v0.4.0...v0.5.0
 [0.4.0]: https://github.com/wilsonsilva/nostr/compare/v0.3.0...v0.4.0
 [0.3.0]: https://github.com/wilsonsilva/nostr/compare/v0.2.0...v0.3.0
 [0.2.0]: https://github.com/wilsonsilva/nostr/compare/v0.1.0...v0.2.0
--- a/README.md
+++ b/README.md
@@ -4,31 +4,30 @@
 [![Maintainability](https://api.codeclimate.com/v1/badges/c7633eb2c89eb95ee7f2/maintainability)](https://codeclimate.com/github/wilsonsilva/nostr/maintainability)
 [![Test Coverage](https://api.codeclimate.com/v1/badges/c7633eb2c89eb95ee7f2/test_coverage)](https://codeclimate.com/github/wilsonsilva/nostr/test_coverage)

-Asynchronous Nostr client. Please note that the API is likely to change as the gem is still in development and
-has not yet reached a stable release. Use with caution.
+Asynchronous Nostr client for Rubyists.

 ## Table of contents

- [Installation](#installation)
- [Usage](#usage)
-  * [Requiring the gem](#requiring-the-gem)
-  * [Generating a keypair](#generating-a-keypair)
-  * [Generating a private key and a public key](#generating-a-private-key-and-a-public-key)
-  * [Connecting to a Relay](#connecting-to-a-relay)
-  * [WebSocket events](#websocket-events)
-  * [Requesting for events / creating a subscription](#requesting-for-events--creating-a-subscription)
-  * [Stop previous subscriptions](#stop-previous-subscriptions)
-  * [Publishing an event](#publishing-an-event)
-  * [Creating/updating your contact list](#creatingupdating-your-contact-list)
-  * [Sending an encrypted direct message](#sending-an-encrypted-direct-message)
- [Implemented NIPs](#implemented-nips)
- [Development](#development)
+- [Key features](#-key-features)
+- [Installation](#-installation)
+- [Quickstart](#-quickstart)
+- [Documentation](#-documentation)
+- [Implemented NIPs](#-implemented-nips)
+- [Development](#-development)
  * [Type checking](#type-checking)
- [Contributing](#contributing)
- [License](#license)
- [Code of Conduct](#code-of-conduct)
+- [Contributing](#-contributing)
+- [License](#-license)
+- [Code of Conduct](#-code-of-conduct)

-## Installation
+## 🔑 Key features
+
+- Asynchronous
+- Easy to use
+- Fully documented
+- Fully tested
+- Fully typed
+
+## 📦 Installation

 Install the gem and add to the application's Gemfile by executing:

@@ -38,248 +37,103 @@ If bundler is not being used to manage dependencies, install the gem by executin

    $ gem install nostr

-## Usage
+## ⚡️ Quickstart

-### Requiring the gem
-
-All examples below assume that the gem has been required.
+Here is a quick example of how to use the gem. For more detailed documentation, please check the
+[documentation website](https://nostr-ruby.com).

 ```ruby
+# Require the gem
 require 'nostr'
-```

-### Generating a keypair
-
-```ruby
-keygen  = Nostr::Keygen.new
-keypair = keygen.generate_key_pair
-
-keypair.private_key
-keypair.public_key
-```
-
-### Generating a private key and a public key
-
-```ruby
-keygen  = Nostr::Keygen.new
-
-private_key = keygen.generate_private_key
-public_key  = keygen.extract_public_key(private_key)
-```
-
-### Connecting to a Relay
-
-Clients can connect to multiple Relays. In this version, a Client can only connect to a single Relay at a time.
-
-You may instantiate multiple Clients and multiple Relays.
-
-```ruby
+# Instantiate a client
 client = Nostr::Client.new
-relay  = Nostr::Relay.new(url: 'wss://relay.damus.io', name: 'Damus')

+# a) Use an existing keypair
+keypair = Nostr::KeyPair.new(
+  private_key: Nostr::PrivateKey.new('add-your-hex-private-key-here'),
+  public_key: Nostr::PublicKey.new('add-your-hex-public-key-here'),
+)
+
+# b) Or build a keypair from a private key
+keygen = Nostr::Keygen.new
+keypair = keygen.get_key_pair_from_private_key(
+  Nostr::PrivateKey.new('add-your-hex-private-key-here')
+)
+
+# c) Or create a new keypair
+keygen = Nostr::Keygen.new
+keypair = keygen.generate_keypair
+
+# Create a user with the keypair
+user = Nostr::User.new(keypair: keypair)
+
+# Create a signed event
+text_note_event = user.create_event(
+  kind: Nostr::EventKind::TEXT_NOTE,
+  content: 'Your feedback is appreciated, now pay $8'
+)
+
+# Connect asynchronously to a relay
+relay = Nostr::Relay.new(url: 'wss://nostr.wine', name: 'Wine')
 client.connect(relay)
-```

-### WebSocket events
-
-All communication between clients and relays happen in WebSockets.
-
-The `:connect` event is fired when a connection with a WebSocket is opened. You must call `Nostr::Client#connect` first.
-
-```ruby
+# Listen asynchronously for the connect event
 client.on :connect do
-  # all the code goes here
-end
-```
+  # Send the event to the Relay
+  client.publish(text_note_event)

-The `:close` event is fired when a connection with a WebSocket has been closed because of an error.
+  # Create a filter to receive the first 20 text notes
+  # and encrypted direct messages from the relay that
+  # were created in the previous hour
+  filter = Nostr::Filter.new(
+    kinds: [
+      Nostr::EventKind::TEXT_NOTE,
+      Nostr::EventKind::ENCRYPTED_DIRECT_MESSAGE
+    ],
+    since: Time.now.to_i - 3600, # 1 hour ago
+    until: Time.now.to_i,
+    limit: 20,
+  )

-```ruby
-client.on :error do |error_message|
-  puts error_message
+  # Subscribe to events matching conditions of a filter
+  subscription = client.subscribe(filter: filter)
+
+  # Unsubscribe from events matching the filter above
+  client.unsubscribe(subscription.id)
 end

-# > Network error: wss://rsslay.fiatjaf.com: Unable to verify the server certificate for 'rsslay.fiatjaf.com'
-```
-
-The `:message` event is fired when data is received through a WebSocket.
-
-```ruby
+# Listen for incoming messages and print them
 client.on :message do |message|
  puts message
 end

-# [
-#   "EVENT",
-#   "d34107357089bfc9882146d3bfab0386",
-#   {
-#     "content":"",
-#     "created_at":1676456512,
-#     "id":"18f63550da74454c5df7caa2a349edc5b2a6175ea4c5367fa4b4212781e5b310",
-#     "kind":3,
-#     "pubkey":"117a121fa41dc2caa0b3d6c5b9f42f90d114f1301d39f9ee96b646ebfee75e36",
-#     "sig":"d171420bd62cf981e8f86f2dd8f8f86737ea2bbe2d98da88db092991d125535860d982139a3c4be39886188613a9912ef380be017686a0a8b74231dc6e0b03cb",
-#     "tags":[
-#       ["p","1cc821cc2d47191b15fcfc0f73afed39a86ac6fb34fbfa7993ee3e0f0186ef7c"]
-#     ]
-#   }
-# ]
-```
+# Listen for error messages
+client.on :error do |error_message|
+  # Handle the error
+end

-The `:close` event is fired when a connection with a WebSocket is closed.
-
-```ruby
+# Listen for the close event
 client.on :close do |code, reason|
-  # you may attempt to reconnect
-
-  client.connect(relay)
+  # You may attempt to reconnect to the relay here
 end
 ```

-### Requesting for events / creating a subscription
+## 📚 Documentation

-A client can request events and subscribe to new updates after it has established a connection with the Relay.
+I made a detailed documentation for this gem and it's usage. The code is also fully documented using YARD.

-You may use a `Nostr::Filter` instance with as many attributes as you wish:
+- [Guide documentation](https://nostr-ruby.com)
+- [YARD documentation](https://rubydoc.info/gems/nostr)

-```ruby
-client.on :connect do
-  filter = Nostr::Filter.new(
-    ids: ['8535d5e2d7b9dc07567f676fbe70428133c9884857e1915f5b1cc6514c2fdff8'],
-    authors: ['ae00f88a885ce76afad5cbb2459ef0dcf0df0907adc6e4dac16e1bfbd7074577'],
-    kinds: [Nostr::EventKind::TEXT_NOTE],
-    e: ["f111593a72cc52a7f0978de5ecf29b4653d0cf539f1fa50d2168fc1dc8280e52"],
-    p: ["f1f9b0996d4ff1bf75e79e4cc8577c89eb633e68415c7faf74cf17a07bf80bd8"],
-    since: 1230981305,
-    until: 1292190341,
-    limit: 420,
-  )
+## ✅ Implemented NIPs

-  subscription = client.subscribe('a_random_subscription_id', filter)
-end
-```
+- [x] [NIP-01 - Basic protocol flow description](https://github.com/nostr-protocol/nips/blob/master/01.md)
+- [x] [NIP-02 - Contact List and Petnames](https://github.com/nostr-protocol/nips/blob/master/02.md)
+- [x] [NIP-04 - Encrypted Direct Message](https://github.com/nostr-protocol/nips/blob/master/04.md)
+- [x] [NIP-19 - Bech32-encoded entities](https://github.com/nostr-protocol/nips/blob/master/19.md)

-With just a few:
-
-```ruby
-client.on :connect do
-  filter = Nostr::Filter.new(kinds: [Nostr::EventKind::TEXT_NOTE])
-  subscription = client.subscribe('a_random_subscription_id', filter)
-end
-```
-
-Or omit the filter:
-
-```ruby
-client.on :connect do
-  subscription = client.subscribe('a_random_subscription_id')
-end
-```
-
-Or even omit the subscription id:
-
-```ruby
-client.on :connect do
-  subscription = client.subscribe('a_random_subscription_id')
-end
-```
-
-### Stop previous subscriptions
-
-You can stop receiving messages from a subscription by calling `#unsubscribe`:
-
-```ruby
-client.unsubscribe('your_subscription_id')
-```
-
-### Publishing an event
-
-To publish an event you need a keypair.
-
-```ruby
-# Create a keypair
-keypair = Nostr::KeyPair.new(
-  private_key: '893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900',
-  public_key: '2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558',
-)
-
-# Add the keypair to the user facade
-user = Nostr::User.new(keypair: keypair)
-
-# Create a signed event
-event = user.create_event(
-  created_at: 1667422587, # optional, defaults to the current time
-  kind: Nostr::EventKind::TEXT_NOTE,
-  tags: [], # optional, defaults to []
-  content: 'Your feedback is appreciated, now pay $8'
-)
-
-# Send it to the Relay
-client.publish(event)
-```
-
-### Creating/updating your contact list
-
-Every new contact list that gets published overwrites the past ones, so it should contain all entries.
-
-```ruby
-# Creating a contact list event with 2 contacts
-update_contacts_event = user.create_event(
-  kind: Nostr::EventKind::CONTACT_LIST,
-  tags: [
-    [
-      "p", # mandatory
-      "32e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245", # public key of the user to add to the contacts
-      "wss://alicerelay.com/", # can be an empty string or can be omitted
-      "alice" # can be an empty string or can be omitted
-    ],
-    [
-      "p", # mandatory
-      "3efdaebb1d8923ebd99c9e7ace3b4194ab45512e2be79c1b7d68d9243e0d2681", # public key of the user to add to the contacts
-      "wss://bobrelay.com/nostr", # can be an empty string or can be omitted
-      "bob" # can be an empty string or can be omitted
-    ],
-  ],
-)
-
-# Send it to the Relay
-client.publish(update_contacts_event)
-```
-
-### Sending an encrypted direct message
-
-```ruby
-sender_private_key = '3185a47e3802f956ca5a2b4ea606c1d51c7610f239617e8f0f218d55bdf2b757'
-
-encrypted_direct_message = Nostr::Events::EncryptedDirectMessage.new(
-   sender_private_key: sender_private_key,
-   recipient_public_key: '6c31422248998e300a1a457167565da7d15d0da96651296ee2791c29c11b6aa0',
-   plain_text: 'Your feedback is appreciated, now pay $8',
-   previous_direct_message: 'ccf9fdf3e1466d7c20969c71ec98defcf5f54aee088513e1b73ccb7bd770d460' # optional
-)
-
-encrypted_direct_message.sign(sender_private_key)
-
-# #<Nostr::Events::EncryptedDirectMessage:0x0000000104c9fa68
-# @content="mjIFNo1sSP3KROE6QqhWnPSGAZRCuK7Np9X+88HSVSwwtFyiZ35msmEVoFgRpKx4?iv=YckChfS2oWCGpMt1uQ4GbQ==",
-#   @created_at=1676456512,
-#   @id="daac98826d5eb29f7c013b6160986c4baf4fe6d4b995df67c1b480fab1839a9b",
-#   @kind=4,
-#   @pubkey="8a9d69c56e3c691bec8f9565e4dcbe38ae1d88fffeec3ce66b9f47558a3aa8ca",
-#   @sig="028bb5f5bab0396e2065000c84a4bcce99e68b1a79bb1b91a84311546f49c5b67570b48d4a328a1827e7a8419d74451347d4f55011a196e71edab31aa3d6bdac",
-#   @tags=[["p", "6c31422248998e300a1a457167565da7d15d0da96651296ee2791c29c11b6aa0"], ["e", "ccf9fdf3e1466d7c20969c71ec98defcf5f54aee088513e1b73ccb7bd770d460"]]>
-
-# Send it to the Relay
-client.publish(encrypted_direct_message)
-````
-
-## Implemented NIPs
-
- [x] [NIP-01 - Client](https://github.com/nostr-protocol/nips/blob/master/01.md)
- [x] [NIP-02 - Client](https://github.com/nostr-protocol/nips/blob/master/02.md)
- [x] [NIP-04 - Client](https://github.com/nostr-protocol/nips/blob/master/04.md)
-
-## Development
+## 🔨 Development

 After checking out the repo, run `bin/setup` to install dependencies.

@@ -323,17 +177,22 @@ used to provide type checking and autocompletion in your editor. Run `bundle exe
 an RBS definition for the given Ruby file. And validate all definitions using [Steep](https://github.com/soutaro/steep)
 with the command `bundle exec steep check`.

-## Contributing
+## 🐞 Issues & Bugs
+
+If you find any issues or bugs, please report them [here](https://github.com/wilsonsilva/nostr/issues), I will be happy
+to have a look at them and fix them as soon as possible.
+
+## 🤝 Contributing

 Bug reports and pull requests are welcome on GitHub at https://github.com/wilsonsilva/nostr.
 This project is intended to be a safe, welcoming space for collaboration, and contributors are expected to adhere
 to the [code of conduct](https://github.com/wilsonsilva/nostr/blob/main/CODE_OF_CONDUCT.md).

-## License
+## 📜 License

 The gem is available as open source under the terms of the [MIT License](https://opensource.org/licenses/MIT).

-## Code of Conduct
+## 👔 Code of Conduct

 Everyone interacting in the Nostr project's codebases, issue trackers, chat rooms and mailing lists is expected
 to follow the [code of conduct](https://github.com/wilsonsilva/nostr/blob/main/CODE_OF_CONDUCT.md).
--- a/docs/.gitignore
+++ b/docs/.gitignore
@@ -0,0 +1,4 @@
+/node_modules/
+.vitepress/dist
+.vitepress/temp
+.vitepress/cache
--- a/docs/.vitepress/config.mjs
+++ b/docs/.vitepress/config.mjs
@@ -0,0 +1,112 @@
+import { defineConfig } from 'vitepress'
+import { withMermaid } from "vitepress-plugin-mermaid";
+
+// https://vitepress.dev/reference/site-config
+// https://www.npmjs.com/package/vitepress-plugin-mermaid
+export default defineConfig(withMermaid({
+  title: "Nostr",
+  description: "Documentation of the Nostr Ruby gem",
+  // https://vitepress.dev/reference/site-config#head
+  head: [
+    ['link', { rel: 'icon', href: '/favicon.ico' }]
+  ],
+  themeConfig: {
+    // https://vitepress.dev/reference/default-theme-last-updated
+    lastUpdated: true,
+
+    // https://vitepress.dev/reference/default-theme-config
+    nav: [
+      { text: 'Home', link: '/' },
+      { text: 'Guide', link: '/getting-started/overview' }
+    ],
+
+    // https://vitepress.dev/reference/default-theme-search
+    search: {
+      provider: 'local'
+    },
+
+    // https://vitepress.dev/reference/default-theme-sidebar
+    sidebar: [
+      {
+        text: 'Getting started',
+        collapsed: false,
+        items: [
+          { text: 'Overview', link: '/getting-started/overview' },
+          { text: 'Installation', link: '/getting-started/installation' },
+        ]
+      },
+      {
+        text: 'Core',
+        collapsed: false,
+        items: [
+          { text: 'Client', link: '/core/client' },
+          { text: 'Keys', link: '/core/keys' },
+          { text: 'User', link: '/core/user' },
+        ]
+      },
+      {
+        text: 'Relays',
+        items: [
+          { text: 'Connecting to a relay', link: '/relays/connecting-to-a-relay' },
+          { text: 'Publishing events', link: '/relays/publishing-events' },
+          { text: 'Receiving events', link: '/relays/receiving-events' },
+        ]
+      },
+      {
+        text: 'Subscriptions',
+        collapsed: false,
+        items: [
+          { text: 'Creating a subscription', link: '/subscriptions/creating-a-subscription' },
+          { text: 'Filtering subscription events', link: '/subscriptions/filtering-subscription-events' },
+          { text: 'Updating a subscription', link: '/subscriptions/updating-a-subscription' },
+          { text: 'Deleting a subscription', link: '/subscriptions/deleting-a-subscription' },
+        ]
+      },
+      {
+        text: 'Events',
+        link: '/events',
+        collapsed: false,
+        items: [
+          { text: 'Set Metadata', link: '/events/set-metadata' },
+          { text: 'Text Note', link: '/events/text-note' },
+          { text: 'Recommend Server', link: '/events/recommend-server' },
+          { text: 'Contact List', link: '/events/contact-list' },
+          { text: 'Encrypted Direct Message', link: '/events/encrypted-direct-message' },
+        ]
+      },
+      {
+        text: 'Common use cases',
+        collapsed: false,
+        items: [
+          { text: 'Bech32 enc/decoding (NIP-19)', link: '/common-use-cases/bech32-encoding-and-decoding-(NIP-19)' },
+        ]
+      },
+      {
+        text: 'Implemented NIPs',
+        link: '/implemented-nips',
+      },
+    ],
+
+    // https://vitepress.dev/reference/default-theme-config#sociallinks
+    socialLinks: [
+      { icon: 'github', link: 'https://github.com/wilsonsilva/nostr' }
+    ],
+
+    // https://vitepress.dev/reference/default-theme-edit-link
+    editLink: {
+      pattern: 'https://github.com/wilsonsilva/nostr/edit/main/docs/:path',
+      text: 'Edit this page on GitHub'
+    },
+
+    // https://vitepress.dev/reference/default-theme-footer
+    footer: {
+      message: 'Released under the <a href="https://github.com/wilsonsilva/nostr/blob/main/LICENSE.txt">MIT License</a>.',
+      copyright: 'Copyright © 2023-present <a href="https://github.com/wilsonsilva">Wilson Silva</a>'
+    }
+  },
+
+  // https://vitepress.dev/reference/site-config#ignoredeadlinks
+  ignoreDeadLinks: [
+    /^https?:\/\/localhost/
+  ],
+}))
--- a/docs/README.md
+++ b/docs/README.md
@@ -0,0 +1,44 @@
+# Nostr Docs
+
+VitePress-powered documentation for the Nostr Ruby gem.
+
+## Live Demo
+
+https://nostr-ruby.com/
+
+## Development
+
+### Requirements
+
+- [Bun](https://bun.sh/)
+
+### Installation
+
+```shell
+bun install
+```
+
+### Tasks
+
+The `docs:dev` script will start a local dev server with instant hot updates. Run it with the following command:
+
+```shell
+bun run docs:dev
+```
+
+Run this command to build the docs:
+
+```shell
+bun run docs:build
+```
+
+Once built, preview it locally by running:
+
+```shell
+bun run docs:preview
+```
+
+The preview command will boot up a local static web server that will serve the output directory .`vitepress/dist` at
+http://localhost:4173. You can use this to make sure everything looks good before pushing to production.
+
+
--- a/docs/api-examples.md
+++ b/docs/api-examples.md
@@ -0,0 +1,49 @@
+---
+outline: deep
+---
+
+# Runtime API Examples
+
+This page demonstrates usage of some of the runtime APIs provided by VitePress.
+
+The main `useData()` API can be used to access site, theme, and page data for the current page. It works in both `.md` and `.vue` files:
+
+```md
+<script setup>
+import { useData } from 'vitepress'
+
+const { theme, page, frontmatter } = useData()
+</script>
+
+## Results
+
+### Theme Data
+<pre>{{ theme }}</pre>
+
+### Page Data
+<pre>{{ page }}</pre>
+
+### Page Frontmatter
+<pre>{{ frontmatter }}</pre>
+```
+
+<script setup>
+import { useData } from 'vitepress'
+
+const { site, theme, page, frontmatter } = useData()
+</script>
+
+## Results
+
+### Theme Data
+<pre>{{ theme }}</pre>
+
+### Page Data
+<pre>{{ page }}</pre>
+
+### Page Frontmatter
+<pre>{{ frontmatter }}</pre>
+
+## More
+
+Check out the documentation for the [full list of runtime APIs](https://vitepress.dev/reference/runtime-api#usedata).
--- a/docs/bun.lockb
+++ b/docs/bun.lockb
--- a/docs/common-use-cases/bech32-encoding-and-decoding-(NIP-19).md
+++ b/docs/common-use-cases/bech32-encoding-and-decoding-(NIP-19).md
@@ -0,0 +1,190 @@
+# Encoding/decoding bech-32 strings (NIP-19)
+
+[NIP-19](https://github.com/nostr-protocol/nips/blob/master/19.md) standardizes bech32-formatted strings that can be
+used to display keys, ids and other information in clients. These formats are not meant to be used anywhere in the core
+protocol, they are only meant for displaying to users, copy-pasting, sharing, rendering QR codes and inputting data.
+
+
+In order to guarantee the deterministic nature of the documentation, the examples below assume that there is a `keypair`
+variable with the following values:
+
+```ruby
+keypair = Nostr::KeyPair.new(
+  private_key: Nostr::PrivateKey.new('67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa'),
+  public_key: Nostr::PublicKey.new('7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'),
+)
+
+keypair.private_key # => '67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa'
+keypair.public_key # => '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'
+```
+
+## Public key (npub)
+
+### Encoding
+
+```ruby
+npub = Nostr::Bech32.npub_encode('7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e')
+npub # => 'npub10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qzvjptg'
+```
+
+### Decoding
+
+```ruby
+type, public_key = Nostr::Bech32.decode('npub10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qzvjptg')
+type # => 'npub'
+public_key # => '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'
+```
+
+## Private key (nsec)
+
+### Encoding
+
+```ruby
+nsec = Nostr::Bech32.nsec_encode('67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa')
+nsec # => 'nsec1vl029mgpspedva04g90vltkh6fvh240zqtv9k0t9af8935ke9laqsnlfe5'
+```
+
+### Decoding
+
+```ruby
+type, private_key = Nostr::Bech32.decode('nsec1vl029mgpspedva04g90vltkh6fvh240zqtv9k0t9af8935ke9laqsnlfe5')
+type # => 'npub'
+private_key # => '67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa'
+```
+
+## Relay (nrelay)
+
+### Encoding
+
+```ruby
+nrelay = Nostr::Bech32.nrelay_encode('wss://relay.damus.io')
+nrelay # => 'nrelay1qq28wumn8ghj7un9d3shjtnyv9kh2uewd9hsc5zt2x'
+```
+
+### Decoding
+
+```ruby
+type, data = Nostr::Bech32.decode('nrelay1qq28wumn8ghj7un9d3shjtnyv9kh2uewd9hsc5zt2x')
+
+type # => 'nrelay'
+data.entries.first.label # => 'relay'
+data.entries.first.value # => 'wss://relay.damus.io'
+```
+
+## Event (nevent)
+
+### Encoding
+
+```ruby{8-12}
+user = Nostr::User.new(keypair: keypair)
+text_note_event = user.create_event(
+  kind: Nostr::EventKind::TEXT_NOTE,
+  created_at: 1700467997,
+  content: 'Your feedback is appreciated, now pay $8'
+)
+
+nevent = Nostr::Bech32.nevent_encode(
+  id: text_note_event.id,
+  relays: ['wss://relay.damus.io', 'wss://nos.lol'],
+  kind: Nostr::EventKind::TEXT_NOTE,
+)
+
+nevent # => 'nevent1qgsqlkuslr3rf56qpmd0m5ndfyl39m7q6l0zcmuly8ue0praxwkjagcpz3mhxue69uhhyetvv9ujuerpd46hxtnfduqs6amnwvaz7tmwdaejumr0dspsgqqqqqqs03k8v3'
+```
+
+### Decoding
+
+```ruby
+type, event = Nostr::Bech32.decode('nevent1qgsqlkuslr3rf56qpmd0m5ndfyl39m7q6l0zcmuly8ue0praxwkjagcpz3mhxue69uhhyetvv9ujuerpd46hxtnfduqs6amnwvaz7tmwdaejumr0dspsgqqqqqqs03k8v3')
+
+type # => 'nevent'
+event.entries[0].label # => 'author'
+event.entries[0].value # => '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'
+event.entries[1].relay # => 'relay'
+event.entries[1].value # => 'wss://relay.damus.io'
+event.entries[2].label # => 'relay'
+event.entries[2].value # => 'wss://nos.lol'
+event.entries[3].label # => 'kind'
+event.entries[3].value # => 1
+```
+
+## Address (naddr)
+
+### Encoding
+
+```ruby
+naddr = Nostr::Bech32.naddr_encode(
+  pubkey: keypair.public_key,
+  relays: ['wss://relay.damus.io', 'wss://nos.lol'],
+  kind: Nostr::EventKind::TEXT_NOTE,
+  identifier: 'damus',
+)
+
+naddr # => 'naddr1qgs8ul5ug253hlh3n75jne0a5xmjur4urfxpzst88cnegg6ds6ka7nspz3mhxue69uhhyetvv9ujuerpd46hxtnfduqs6amnwvaz7tmwdaejumr0dspsgqqqqqqsqptyv9kh2uc3qfs2p'
+```
+
+### Decoding
+
+```ruby
+type, addr = Nostr::Bech32.decode('naddr1qgs8ul5ug253hlh3n75jne0a5xmjur4urfxpzst88cnegg6ds6ka7nspz3mhxue69uhhyetvv9ujuerpd46hxtnfduqs6amnwvaz7tmwdaejumr0dspsgqqqqqqsqptyv9kh2uc3qfs2p')
+
+type # => 'naddr'
+addr.entries[0].label # => 'author'
+addr.entries[0].value # => '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'
+addr.entries[1].label # => 'relay'
+addr.entries[1].value # => 'wss://relay.damus.io'
+addr.entries[2].label # => 'relay'
+addr.entries[2].value # => 'wss://nos.lol'
+addr.entries[3].label # => 'kind'
+addr.entries[3].value # => 1
+addr.entries[4].label # => 'identifier'
+addr.entries[4].value # => 'damus'
+```
+
+## Profile (nprofile)
+
+### Encoding
+```ruby
+relay_urls = %w[wss://relay.damus.io wss://nos.lol]
+nprofile = Nostr::Bech32.nprofile_encode(pubkey: keypair.public_key, relays: relay_urls)
+
+nprofile # => nprofile1qqs8ul5ug253hlh3n75jne0a5xmjur4urfxpzst88cnegg6ds6ka7nspz3mhxue69uhhyetvv9ujuerpd46hxtnfduqs6amnwvaz7tmwdaejumr0dsxe58m5
+```
+
+### Decoding
+
+```ruby
+type, profile = Nostr::Bech32.decode('nprofile1qqs8ul5ug253hlh3n75jne0a5xmjur4urfxpzst88cnegg6ds6ka7nspz3mhxue69uhhyetvv9ujuerpd46hxtnfduqs6amnwvaz7tmwdaejumr0dsxe58m5')
+
+type # => 'nprofile'
+profile.entries[0].label # => 'pubkey'
+profile.entries[0].value # => '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'
+profile.entries[1].label # => 'relay'
+profile.entries[1].value # => 'wss://relay.damus.io'
+profile.entries[2].label # => 'relay'
+profile.entries[2].value # => 'wss://nos.lol'
+```
+
+## Other simple types (note)
+
+### Encoding
+
+```ruby{8-9}
+user = Nostr::User.new(keypair: keypair)
+text_note_event = user.create_event(
+  kind: Nostr::EventKind::TEXT_NOTE,
+  created_at: 1700467997,
+  content: 'Your feedback is appreciated, now pay $8'
+)
+
+note = Nostr::Bech32.encode(hrp: 'note', data: text_note_event.id)
+note # => 'note10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qnx3ujq'
+```
+
+### Decoding
+
+```ruby
+type, note = Nostr::Bech32.decode('note1pldep78zxnf5qrk6lhfx6jflzthup47793he7g0ej7z86vad963s42v0rr')
+type # => 'note'
+note # => '0fdb90f8e234d3400edafdd26d493f12efc0d7de2c6f9f21f997847d33ad2ea3'
+```
--- a/docs/core/client.md
+++ b/docs/core/client.md
@@ -0,0 +1,108 @@
+# Client
+
+Clients establish a WebSocket connection to [relays](../relays/connecting-to-a-relay). Through this connection, clients
+communicate and subscribe to a range of [Nostr events](../events) based on specified subscription filters. These filters
+define the Nostr events a client wishes to receive updates about.
+
+::: info
+Clients do not need to sign up or create an account to use Nostr. Upon connecting to a relay, a client provides
+its subscription filters. The relay then streams events that match these filters to the client for the duration of the
+connection.
+:::
+
+## WebSocket events
+
+Communication between clients and relays happen via WebSockets. The client will emit WebSocket events when the
+connection is __opened__, __closed__, when a __message__ is received or when there's an __error__.
+
+::: info
+WebSocket events are not [Nostr events](https://nostr.com/the-protocol/events). They are events emitted by the
+WebSocket connection. The WebSocket `:message` event, however, contains a Nostr event in its payload.
+:::
+
+### connect
+
+The `:connect` event is fired when a connection with a WebSocket is opened. You must call `Nostr::Client#connect` first.
+
+```ruby
+client = Nostr::Client.new
+relay = Nostr::Relay.new(url: 'wss://relay.damus.io', name: 'Damus')
+
+client.on :connect do
+  # When this block executes, you're connected to the relay
+end
+
+# Connect to a relay asynchronously
+client.connect(relay)
+```
+
+Once the connection is open, you can send events to the relay, manage subscriptions, etc.
+
+::: tip
+Define the connection event handler before calling
+[`Nostr::Client#connect`](https://www.rubydoc.info/gems/nostr/Nostr/Client#connect-instance_method). Otherwise,
+you may miss the event.
+:::
+
+### error
+
+The `:error` event is fired when a connection with a WebSocket has been closed because of an error.
+
+```ruby
+client.on :error do |error_message|
+  puts error_message
+end
+
+# > Network error: wss://rsslay.fiatjaf.com: Unable to verify the
+# server certificate for 'rsslay.fiatjaf.com'
+```
+
+### message
+
+The `:message` event is fired when data is received through a WebSocket.
+
+```ruby
+client.on :message do |message|
+  puts message
+end
+```
+
+The message will be one of these 4 types, which must also be JSON arrays, according to the following patterns:
+- `["EVENT", <subscription_id>, <event JSON>]`
+- `["OK", <event_id>, <true|false>, <message>]`
+- `["EOSE", <subscription_id>]`
+- `["NOTICE", <message>]`
+
+::: details Click me to see how a WebSocket message looks like
+```ruby
+[
+  "EVENT",
+  "d34107357089bfc9882146d3bfab0386",
+  {
+    "content": "",
+    "created_at": 1676456512,
+    "id": "18f63550da74454c5df7caa2a349edc5b2a6175ea4c5367fa4b4212781e5b310",
+    "kind": 3,
+    "pubkey": "117a121fa41dc2caa0b3d6c5b9f42f90d114f1301d39f9ee96b646ebfee75e36",
+    "sig": "d171420bd62cf981e8f86f2dd8f8f86737ea2bbe2d98da88db092991d125535860d982139a3c4be39886188613a9912ef380be017686a0a8b74231dc6e0b03cb",
+    "tags":[
+      ["p", "1cc821cc2d47191b15fcfc0f73afed39a86ac6fb34fbfa7993ee3e0f0186ef7c"]
+    ]
+  }
+]
+```
+:::
+
+### close
+
+The `:close` event is fired when a connection with a WebSocket is closed.
+
+```ruby
+client.on :close do |code, reason|
+  puts "Error: #{code} - #{reason}"
+end
+```
+
+::: tip
+This handler is useful to attempt to reconnect to the relay.
+:::
--- a/docs/core/keys.md
+++ b/docs/core/keys.md
@@ -0,0 +1,136 @@
+# Keys
+
+To [sign events](#signing-an-event), you need a **private key**. To verify signatures, you need a **public key**. The combination of a
+private and a public key is called a **keypair**.
+
+Both public and private keys are 64-character hexadecimal strings. They can be represented in bech32 format,
+which is a human-readable format that starts with `nsec` for private keys and `npub` for public keys.
+
+There are a few ways to generate a keypair.
+
+## a) Generating a keypair
+
+If you don't have any keys, you can generate a keypair using the
+[`Nostr::Keygen`](https://www.rubydoc.info/gems/nostr/Nostr/Keygen) class:
+
+```ruby
+keygen  = Nostr::Keygen.new
+keypair = keygen.generate_key_pair
+
+keypair.private_key # => '67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa'
+keypair.public_key # => '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'
+```
+
+## b) Generating a private key and a public key
+
+Alternatively, if you have already generated a private key, you can extract the corresponding public key by calling
+`Keygen#extract_public_key`:
+
+```ruby
+keygen  = Nostr::Keygen.new
+
+private_key = keygen.generate_private_key
+public_key  = keygen.extract_public_key(private_key)
+
+private_key # => '67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa'
+public_key # => '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'
+```
+
+## c) Using existing hexadecimal keys
+
+If you already have a private key and a public key in hexadecimal format, you can create a keypair using the
+`Nostr::KeyPair` class:
+
+```ruby
+keypair = Nostr::KeyPair.new(
+  private_key: Nostr::PrivateKey.new('67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa'),
+  public_key: Nostr::PublicKey.new('7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'),
+)
+
+keypair.private_key # => '67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa'
+keypair.public_key # => '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'
+```
+
+### d) Use existing bech32 keys
+
+If you already have a private key and a public key in bech32 format, you can create a keypair using the
+`Nostr::KeyPair` class:
+
+```ruby
+keypair = Nostr::KeyPair.new(
+  private_key: Nostr::PrivateKey.from_bech32('nsec1vl029mgpspedva04g90vltkh6fvh240zqtv9k0t9af8935ke9laqsnlfe5'),
+  public_key: Nostr::PublicKey.from_bech32('npub10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qzvjptg'),
+)
+
+keypair.private_key # => '67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa'
+keypair.public_key # => '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'
+```
+
+## e) Using an existing hexadecimal private key
+
+If you already have a private key in hexadecimal format, you can create a keypair using the method
+[`Nostr::Keygen#get_key_pair_from_private_key`](https://www.rubydoc.info/gems/nostr/Nostr/Keygen#get_key_pair_from_private_key-instance_method):
+
+```ruby
+private_key = Nostr::PrivateKey.new('67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa')
+
+keygen= Nostr::Keygen.new
+keypair = keygen.get_key_pair_from_private_key(private_key)
+
+keypair.private_key # => '67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa'
+keypair.public_key # => '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'
+```
+
+## f) Using an existing bech32 private key
+
+If you already have a private key in bech32 format, you can create a keypair using the methods
+[`Nostr::PrivateKey.from_bech32`](https://www.rubydoc.info/gems/nostr/Nostr/PrivateKey.from_bech32-class_method) and
+[`Nostr::Keygen#get_key_pair_from_private_key`](https://www.rubydoc.info/gems/nostr/Nostr/Keygen#get_key_pair_from_private_key-instance_method):
+
+```ruby
+private_key = Nostr::PrivateKey.from_bech32('nsec1vl029mgpspedva04g90vltkh6fvh240zqtv9k0t9af8935ke9laqsnlfe5')
+
+keygen= Nostr::Keygen.new
+keypair = keygen.get_key_pair_from_private_key(private_key)
+
+keypair.private_key # => '67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa'
+keypair.public_key # => '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'
+```
+
+## Signing an event
+
+KeyPairs are used to sign [events](../events). To create a signed event, you need to instantiate a
+[`Nostr::User`](https://www.rubydoc.info/gems/nostr/Nostr/User) with a keypair:
+
+```ruby{8,11-14}
+# Use an existing keypair
+keypair = Nostr::KeyPair.new(
+  private_key: Nostr::PrivateKey.new('67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa'),
+  public_key: Nostr::PublicKey.new('7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e'),
+)
+
+# Add the keypair to a user
+user = Nostr::User.new(keypair: keypair)
+
+# Create signed events
+text_note = user.create_event(
+  kind: Nostr::EventKind::TEXT_NOTE,
+  content: 'Your feedback is appreciated, now pay $8'
+)
+```
+
+::: details Click me to view the text_note
+
+```ruby
+# text_note.to_h
+{
+  id: '030fbc71151379e5b58e7428ed6e7f2884e5dfc9087fd64d1dc4cc677f5097c8',
+  pubkey: '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e', # from the keypair
+  created_at: 1700119819,
+  kind: 1, # Nostr::EventKind::TEXT_NOTE,
+  tags: [],
+  content: 'Your feedback is appreciated, now pay $8',
+  sig: '586877896ef6f7d54fa4dd2ade04e3fdc4dfcd6166dd0df696b3c3c768868c0b690338f5baed6ab4fc717785333cb487363384de9fb0f740ac4775522cb4acb3' # signed with the private key from the keypair
+}
+```
+:::
--- a/docs/core/user.md
+++ b/docs/core/user.md
@@ -0,0 +1,43 @@
+# User
+
+The class [`Nostr::User`](https://www.rubydoc.info/gems/nostr/Nostr/User) is an abstraction to facilitate the creation
+of signed events. It is not required to use it to create events, but it is recommended.
+
+Here's an example of how to create a signed event without the class `Nostr::User`:
+
+```ruby
+event = Nostr::Event.new(
+  pubkey: keypair.public_key,
+  kind: Nostr::EventKind::TEXT_NOTE,
+  tags: [],
+  content: 'Your feedback is appreciated, now pay $8',
+)
+event.sign(keypair.private_key)
+```
+
+::: details Click me to view the event
+
+```ruby
+# event.to_h
+{
+  id: '5feb10973dbcf5f210cfc1f0aa338fee62bed6a29696a67957713599b9baf0eb',
+  pubkey: 'b9b9821074d1b60b8fb4a3983632af3ef9669f55b20d515bf982cda5c439ad61',
+  created_at: 1699847447,
+  kind: 1, # Nostr::EventKind::TEXT_NOTE,
+  tags: [],
+  content: 'Your feedback is appreciated, now pay $8',
+  sig: 'e30f2f08331f224e41a4099d16aefc780bf9f2d1191b71777e1e1789e6b51fdf7bb956f25d4ea9a152d1c66717a9d68c081ce6c89c298c3c5e794914013381ab'
+}
+```
+:::
+
+And here's how to create it with the class `Nostr::User`:
+
+```ruby
+user = Nostr::User.new(keypair: keypair)
+
+event = user.create_event(
+  kind: Nostr::EventKind::TEXT_NOTE,
+  content: 'Your feedback is appreciated, now pay $8'
+)
+```
--- a/docs/events.md
+++ b/docs/events.md
@@ -0,0 +1,11 @@
+# Events
+
+## Event Kinds
+
+| kind          | description                                                    | NIP                                                            |
+| ------------- |----------------------------------------------------------------| -------------------------------------------------------------- |
+| `0`           | [Metadata](./events/set-metadata)                              | [1](https://github.com/nostr-protocol/nips/blob/master/01.md)  |
+| `1`           | [Short Text Note](./events/text-note)                          | [1](https://github.com/nostr-protocol/nips/blob/master/01.md)  |
+| `2`           | [Recommend Relay](./events/recommend-server)                   |                                                                |
+| `3`           | [Contacts](./events/contact-list)                              | [2](https://github.com/nostr-protocol/nips/blob/master/02.md)  |
+| `4`           | [Encrypted Direct Messages](./events/encrypted-direct-message) | [4](https://github.com/nostr-protocol/nips/blob/master/04.md)  |
--- a/docs/events/contact-list.md
+++ b/docs/events/contact-list.md
@@ -0,0 +1,29 @@
+# Contact List
+
+## Creating/updating your contact list
+
+Every new contact list that gets published overwrites the past ones, so it should contain all entries.
+
+```ruby
+# Creating a contact list event with 2 contacts
+update_contacts_event = user.create_event(
+  kind: Nostr::EventKind::CONTACT_LIST,
+  tags: [
+    [
+      "p", # mandatory
+      "32e1827635450ebb3c5a7d12c1f8e7b2b514439ac10a67eef3d9fd9c5c68e245", # public key of the user to add to the contacts
+      "wss://alicerelay.com/", # can be an empty string or can be omitted
+      "alice" # can be an empty string or can be omitted
+    ],
+    [
+      "p", # mandatory
+      "3efdaebb1d8923ebd99c9e7ace3b4194ab45512e2be79c1b7d68d9243e0d2681", # public key of the user to add to the contacts
+      "wss://bobrelay.com/nostr", # can be an empty string or can be omitted
+      "bob" # can be an empty string or can be omitted
+    ],
+  ],
+)
+
+# Send it to the Relay
+client.publish(update_contacts_event)
+```
--- a/docs/events/encrypted-direct-message.md
+++ b/docs/events/encrypted-direct-message.md
@@ -0,0 +1,28 @@
+# Encrypted Direct Message
+
+## Sending an encrypted direct message
+
+```ruby
+sender_private_key = '3185a47e3802f956ca5a2b4ea606c1d51c7610f239617e8f0f218d55bdf2b757'
+
+encrypted_direct_message = Nostr::Events::EncryptedDirectMessage.new(
+   sender_private_key: sender_private_key,
+   recipient_public_key: '6c31422248998e300a1a457167565da7d15d0da96651296ee2791c29c11b6aa0',
+   plain_text: 'Your feedback is appreciated, now pay $8',
+   previous_direct_message: 'ccf9fdf3e1466d7c20969c71ec98defcf5f54aee088513e1b73ccb7bd770d460' # optional
+)
+
+encrypted_direct_message.sign(sender_private_key)
+
+# #<Nostr::Events::EncryptedDirectMessage:0x0000000104c9fa68
+# @content="mjIFNo1sSP3KROE6QqhWnPSGAZRCuK7Np9X+88HSVSwwtFyiZ35msmEVoFgRpKx4?iv=YckChfS2oWCGpMt1uQ4GbQ==",
+#   @created_at=1676456512,
+#   @id="daac98826d5eb29f7c013b6160986c4baf4fe6d4b995df67c1b480fab1839a9b",
+#   @kind=4,
+#   @pubkey="8a9d69c56e3c691bec8f9565e4dcbe38ae1d88fffeec3ce66b9f47558a3aa8ca",
+#   @sig="028bb5f5bab0396e2065000c84a4bcce99e68b1a79bb1b91a84311546f49c5b67570b48d4a328a1827e7a8419d74451347d4f55011a196e71edab31aa3d6bdac",
+#   @tags=[["p", "6c31422248998e300a1a457167565da7d15d0da96651296ee2791c29c11b6aa0"], ["e", "ccf9fdf3e1466d7c20969c71ec98defcf5f54aee088513e1b73ccb7bd770d460"]]>
+
+# Send it to the Relay
+client.publish(encrypted_direct_message)
+```
--- a/docs/events/recommend-server.md
+++ b/docs/events/recommend-server.md
@@ -0,0 +1,32 @@
+# Recommend Server
+
+The `Recommend Server` event, has a set of tags with the following structure `['e', <event-id>, <relay-url>, <marker>]`
+
+Where:
+
+- `<event-id>` is the id of the event being referenced.
+- `<relay-url>` is the URL of a recommended relay associated with the reference. Clients SHOULD add a valid `<relay-URL>`
+field, but may instead leave it as `''`.
+- `<marker>` is optional and if present is one of `'reply'`, `'root'`, or `'mention'`.
+Those marked with `'reply'` denote the id of the reply event being responded to. Those marked with `'root'` denote the
+root id of the reply thread being responded to. For top level replies (those replying directly to the root event),
+only the `'root'` marker should be used. Those marked with `'mention'` denote a quoted or reposted event id.
+
+A direct reply to the root of a thread should have a single marked `'e'` tag of type `'root'`.
+
+## Recommending a server
+
+```ruby
+recommend_server_event = user.create_event(
+  kind: Nostr::EventKind::RECOMMEND_SERVER,
+  tags: [
+    [
+      'e',
+      '461544014d87c9eaf3e76e021240007dff2c7afb356319f99c741b45749bf82f',
+      'wss://relay.damus.io'
+    ],
+  ]
+)
+
+client.publish(recommend_server_event)
+```
--- a/docs/events/set-metadata.md
+++ b/docs/events/set-metadata.md
@@ -0,0 +1,20 @@
+# Set Metadata
+
+In the `Metadata` event, the `content` is set to a stringified JSON object
+`{name: <username>, about: <string>, picture: <url, string>}` describing the [user](../core/user) who created the event. A relay may
+delete older events once it gets a new one for the same pubkey.
+
+## Setting the user's metadata
+
+```ruby
+metadata_event = user.create_event(
+  kind: Nostr::EventKind::SET_METADATA,
+  content: {
+    name: 'Wilson Silva',
+    about: 'Used to make hydrochloric acid bombs in high school.',
+    picture: 'https://thispersondoesnotexist.com/'
+  }
+)
+
+client.publish(metadata_event)
+```
--- a/docs/events/text-note.md
+++ b/docs/events/text-note.md
@@ -0,0 +1,15 @@
+# Text Note
+
+In the `Text Note` event, the `content` is set to the plaintext content of a note (anything the user wants to say).
+Content that must be parsed, such as Markdown and HTML, should not be used.
+
+## Sending a text note event
+
+```ruby
+text_note_event = user.create_event(
+  kind: Nostr::EventKind::TEXT_NOTE,
+  content: 'Your feedback is appreciated, now pay $8'
+)
+
+client.publish(text_note_event)
+```
--- a/docs/getting-started/installation.md
+++ b/docs/getting-started/installation.md
@@ -0,0 +1,21 @@
+# Installation
+
+Install the gem and add to the application's Gemfile by executing:
+
+```shell
+bundle add nostr
+```
+
+If bundler is not being used to manage dependencies, install the gem by executing:
+
+```shell
+gem install nostr
+```
+
+## Requiring the gem
+
+All examples in this guide assume that the gem has been required:
+
+```ruby
+require 'nostr'
+```
--- a/docs/getting-started/overview.md
+++ b/docs/getting-started/overview.md
@@ -0,0 +1,170 @@
+---
+editLink: true
+---
+
+# Getting started
+
+This gem abstracts the complexity that you would face when trying to connect to relays web sockets, send and receive
+events, handle events callbacks and much more.
+
+## Visual overview
+
+Begin your journey with an overview of the essential functions. A visual representation below maps out the key
+components we'll delve into in this section.
+
+```mermaid
+classDiagram
+    class Client {
+        connect(relay)
+        publish(event)
+        subscribe(subscription_id, filter)
+        unsubscribe(subscription_id)
+    }
+    class Relay {
+        url
+        name
+    }
+    class Event {
+        pubkey
+        created_at
+        kind
+        tags
+        content
+        add_event_reference(event_id)
+        add_pubkey_reference(pubkey)
+        serialize()
+        to_h()
+        sign(private_key)
+    }
+    class Subscription {
+        id
+        filter
+    }
+    class Filter {
+        ids
+        authors
+        kinds
+        since
+        until
+        limit
+        to_h()
+    }
+    class EventKind {
+        <<Enumeration>>
+        SET_METADATA
+        TEXT_NOTE
+        RECOMMEND_SERVER
+        CONTACT_LIST
+        ENCRYPTED_DIRECT_MESSAGE
+    }
+    class KeyPair {
+        private_key
+        public_key
+    }
+    class Keygen {
+        generate_key_pair()
+        generate_private_key()
+        extract_public_key(private_key)
+    }
+    class User {
+        keypair
+        create_event(event_attributes)
+    }
+
+    Client --> Relay : connects via <br> WebSockets to
+    Client --> Event : uses WebSockets to <br> publish and receive
+    Client --> Subscription : receives Events via
+    Subscription --> Filter : uses
+    Event --> EventKind : is of kind
+    User --> KeyPair : has
+    User --> Event : creates and signs
+    User --> Keygen : uses to generate keys
+    Keygen --> KeyPair : generates
+```
+
+## Code overview
+
+Explore the provided code snippet to learn about initializing the Nostr [client](../core/client.md), generating
+a [keypair](../core/keys), [publishing](../relays/publishing-events) an event, and
+efficiently [managing event subscriptions](../subscriptions/creating-a-subscription) (including event reception,
+filtering, and WebSocket event handling).
+
+```ruby
+# Require the gem
+require 'nostr'
+
+# Instantiate a client
+client = Nostr::Client.new
+
+# a) Use an existing keypair
+keypair = Nostr::KeyPair.new(
+  private_key: Nostr::PrivateKey.new('your-hex-private-key'),
+  public_key: Nostr::PublicKey.new('your-hex-public-key'),
+)
+
+# b) Or build a keypair from a private key
+keygen = Nostr::Keygen.new
+keypair = keygen.get_key_pair_from_private_key(
+  Nostr::PrivateKey.new('your-hex-private-key')
+)
+
+# c) Or create a new keypair
+keygen = Nostr::Keygen.new
+keypair = keygen.generate_keypair
+
+# Create a user with the keypair
+user = Nostr::User.new(keypair: keypair)
+
+# Create a signed event
+text_note_event = user.create_event(
+  kind: Nostr::EventKind::TEXT_NOTE,
+  content: 'Your feedback is appreciated, now pay $8'
+)
+
+# Connect asynchronously to a relay
+relay = Nostr::Relay.new(url: 'wss://nostr.wine', name: 'Wine')
+client.connect(relay)
+
+# Listen asynchronously for the connect event
+client.on :connect do
+  # Send the event to the Relay
+  client.publish(text_note_event)
+
+  # Create a filter to receive the first 20 text notes
+  # and encrypted direct messages from the relay that
+  # were created in the previous hour
+  filter = Nostr::Filter.new(
+    kinds: [
+      Nostr::EventKind::TEXT_NOTE,
+      Nostr::EventKind::ENCRYPTED_DIRECT_MESSAGE
+    ],
+    since: Time.now.to_i - 3600, # 1 hour ago
+    until: Time.now.to_i,
+    limit: 20,
+  )
+
+  # Subscribe to events matching conditions of a filter
+  subscription = client.subscribe(filter: filter)
+
+  # Unsubscribe from events matching the filter above
+  client.unsubscribe(subscription.id)
+end
+
+# Listen for incoming messages and print them
+client.on :message do |message|
+  puts message
+end
+
+# Listen for error messages
+client.on :error do |error_message|
+  # Handle the error
+end
+
+# Listen for the close event
+client.on :close do |code, reason|
+  # You may attempt to reconnect to the relay here
+end
+```
+
+Beyond what's covered here, the Nostr protocol and this gem boast a wealth of additional functionalities. For an
+in-depth exploration of these capabilities, proceed to the next page.
--- a/docs/implemented-nips.md
+++ b/docs/implemented-nips.md
@@ -0,0 +1,9 @@
+# Implemented NIPs
+
+NIPs stand for Nostr Implementation Possibilities. They exist to document what may be implemented by Nostr-compatible
+relay and client software.
+
+- [NIP-01: Basic protocol flow description](https://github.com/nostr-protocol/nips/blob/master/01.md)
+- [NIP-02: Contact List and Petnames](https://github.com/nostr-protocol/nips/blob/master/02.md)
+- [NIP-04: Encrypted Direct Message](https://github.com/nostr-protocol/nips/blob/master/04.md)
+- [NIP-19: Bech32-encoded entities](https://github.com/nostr-protocol/nips/blob/master/19.md)
--- a/docs/index.md
+++ b/docs/index.md
@@ -0,0 +1,44 @@
+---
+# https://vitepress.dev/reference/default-theme-home-page
+layout: home
+
+hero:
+  name: "Nostr"
+  text: "Ruby"
+  tagline: "The Nostr protocol implemented in a Ruby gem."
+  actions:
+    - theme: brand
+      text: Getting Started
+      link: /getting-started/overview
+    - theme: alt
+      text: View on Github
+      link: https://github.com/wilsonsilva/nostr
+    - theme: alt
+      text: View on RubyDoc
+      link: https://www.rubydoc.info/gems/nostr
+    - theme: alt
+      text: View on RubyGems
+      link: https://rubygems.org/gems/nostr
+
+features:
+  - title: Asynchronous
+    details: Non-blocking I/O for maximum performance.
+    icon: ⚡
+  - title: Lightweight
+    details: Minimal runtime dependencies.
+    icon: 🪶
+  - title: Intuitive
+    details: The API mirrors the Nostr protocol specification domain language.
+    icon: 💡
+  - title: Fully documented
+    details: All code is documented from both the maintainer's as well as the consumer's perspective.
+    icon: 📚
+  - title: Fully tested
+    details: All code is tested with 100% coverage.
+    icon: 🧪
+  - title: Fully typed
+    details: All code is typed with <a href="https://rubygems.org/gems/rbs" target="_blank">RBS</a> with the help of <a href="https://rubygems.org/gems/typeprof" target="_blank">TypeProf</a>. Type correctness is enforced by <a href="https://rubygems.org/gems/steep" target="_blank">Steep</a>.
+    icon: ✅
+
+---
+
--- a/docs/markdown-examples.md
+++ b/docs/markdown-examples.md
@@ -0,0 +1,85 @@
+# Markdown Extension Examples
+
+This page demonstrates some of the built-in markdown extensions provided by VitePress.
+
+## Syntax Highlighting
+
+VitePress provides Syntax Highlighting powered by [Shiki](https://github.com/shikijs/shiki), with additional features like line-highlighting:
+
+**Input**
+
+````
+```js{4}
+export default {
+  data () {
+    return {
+      msg: 'Highlighted!'
+    }
+  }
+}
+```
+````
+
+**Output**
+
+```js{4}
+export default {
+  data () {
+    return {
+      msg: 'Highlighted!'
+    }
+  }
+}
+```
+
+## Custom Containers
+
+**Input**
+
+```md
+::: info
+This is an info box.
+:::
+
+::: tip
+This is a tip.
+:::
+
+::: warning
+This is a warning.
+:::
+
+::: danger
+This is a dangerous warning.
+:::
+
+::: details
+This is a details block.
+:::
+```
+
+**Output**
+
+::: info
+This is an info box.
+:::
+
+::: tip
+This is a tip.
+:::
+
+::: warning
+This is a warning.
+:::
+
+::: danger
+This is a dangerous warning.
+:::
+
+::: details
+This is a details block.
+:::
+
+## More
+
+Check out the documentation for the [full list of markdown extensions](https://vitepress.dev/guide/markdown).
--- a/docs/package.json
+++ b/docs/package.json
@@ -0,0 +1,12 @@
+{
+  "scripts": {
+    "docs:dev": "vitepress dev",
+    "docs:build": "vitepress build",
+    "docs:preview": "vitepress preview"
+  },
+  "devDependencies": {
+    "mermaid": "^10.6.1",
+    "vitepress": "^1.0.0-rc.25",
+    "vitepress-plugin-mermaid": "^2.0.15"
+  }
+}
--- a/docs/relays/connecting-to-a-relay.md
+++ b/docs/relays/connecting-to-a-relay.md
@@ -0,0 +1,21 @@
+# Connecting to a Relay
+
+You must connect your nostr [Client](../core/client) to a relay in order to send and receive [Events](../events).
+Instantiate a [`Nostr::Client`](https://www.rubydoc.info/gems/nostr/Nostr/Client) and a
+[`Nostr::Relay`](https://www.rubydoc.info/gems/nostr/Nostr/Relay) giving it the `url` of your relay. The `name`
+attribute is just descriptive.
+Calling [`Client#connect`](https://www.rubydoc.info/gems/nostr/Nostr/Client#connect-instance_method) attempts to
+establish a WebSocket connection between the Client and the Relay.
+
+```ruby
+client = Nostr::Client.new
+relay = Nostr::Relay.new(url: 'wss://relay.damus.io', name: 'Damus')
+
+# Listen for the connect event
+client.on :connect do
+  # When this block executes, you're connected to the relay
+end
+
+# Connect to a relay asynchronously
+client.connect(relay)
+```
--- a/docs/relays/publishing-events.md
+++ b/docs/relays/publishing-events.md
@@ -0,0 +1,29 @@
+# Publishing events
+
+Create a [signed event](../core/keys) and call the method
+[`Nostr::Client#publish`](https://www.rubydoc.info/gems/nostr/Nostr/Client#publish-instance_method) to send the
+event to the relay.
+
+```ruby{4-8,17}
+# Create a user with the keypair
+user = Nostr::User.new(keypair: keypair)
+
+# Create a signed event
+text_note_event = user.create_event(
+  kind: Nostr::EventKind::TEXT_NOTE,
+  content: 'Your feedback is appreciated, now pay $8'
+)
+
+# Connect asynchronously to a relay
+relay = Nostr::Relay.new(url: 'wss://nostr.wine', name: 'Wine')
+client.connect(relay)
+
+# Listen asynchronously for the connect event
+client.on :connect do
+  # Send the event to the relay
+  client.publish(text_note_event)
+end
+```
+
+The relay will verify the signature of the event with the public key. If the signature is valid, the relay should
+broadcast the event to all subscribers.
--- a/docs/relays/receiving-events.md
+++ b/docs/relays/receiving-events.md
@@ -0,0 +1,6 @@
+# Receiving events
+
+To receive events from Relays, you must create a subscription on the relay. A subscription is a filter that defines the
+events you want to receive.
+
+For more information, read the [Subscription](../subscriptions/creating-a-subscription.md) section.
--- a/docs/subscriptions/creating-a-subscription.md
+++ b/docs/subscriptions/creating-a-subscription.md
@@ -0,0 +1,49 @@
+# Creating a subscription
+
+A client can request events and subscribe to new updates __after__ it has established a connection with the Relay.
+
+You may use a [`Nostr::Filter`](https://www.rubydoc.info/gems/nostr/Nostr/Filter) instance with as many attributes as
+you wish:
+
+```ruby
+client.on :connect do
+  filter = Nostr::Filter.new(
+    ids: ['8535d5e2d7b9dc07567f676fbe70428133c9884857e1915f5b1cc6514c2fdff8'],
+    authors: ['ae00f88a885ce76afad5cbb2459ef0dcf0df0907adc6e4dac16e1bfbd7074577'],
+    kinds: [Nostr::EventKind::TEXT_NOTE],
+    e: ["f111593a72cc52a7f0978de5ecf29b4653d0cf539f1fa50d2168fc1dc8280e52"],
+    p: ["f1f9b0996d4ff1bf75e79e4cc8577c89eb633e68415c7faf74cf17a07bf80bd8"],
+    since: 1230981305,
+    until: 1292190341,
+    limit: 420,
+  )
+
+  subscription = client.subscribe(subscription_id: 'an-id', filter: filter)
+end
+```
+
+With just a few:
+
+```ruby
+client.on :connect do
+  filter = Nostr::Filter.new(kinds: [Nostr::EventKind::TEXT_NOTE])
+  subscription = client.subscribe(subscription_id: 'an-id', filter: filter)
+end
+```
+
+Or omit the filter:
+
+```ruby
+client.on :connect do
+  subscription = client.subscribe(subscription_id: 'an-id')
+end
+```
+
+Or even omit the subscription id:
+
+```ruby
+client.on :connect do
+  subscription = client.subscribe(filter: filter)
+  subscription.id # => "13736f08dee8d7b697222ba605c6fab2" (randomly generated)
+end
+```
--- a/docs/subscriptions/deleting-a-subscription.md
+++ b/docs/subscriptions/deleting-a-subscription.md
@@ -0,0 +1,10 @@
+# Stop previous subscriptions
+
+You can stop receiving messages from a subscription by calling
+[`Nostr::Client#unsubscribe`](https://www.rubydoc.info/gems/nostr/Nostr/Client#unsubscribe-instance_method) with the
+ID of the subscription you want to stop receiving messages from:
+
+```ruby
+client.unsubscribe('your-subscription-id')
+client.unsubscribe(subscription.id)
+```
--- a/docs/subscriptions/filtering-subscription-events.md
+++ b/docs/subscriptions/filtering-subscription-events.md
@@ -0,0 +1,115 @@
+# Filtering events
+
+## Filtering by id
+
+You can filter events by their ids:
+
+```ruby
+filter = Nostr::Filter.new(
+  ids: [
+    # matches events with these exact IDs
+    '8535d5e2d7b9dc07567f676fbe70428133c9884857e1915f5b1cc6514c2fdff8',
+    '461544014d87c9eaf3e76e021240007dff2c7afb356319f99c741b45749bf82f',
+  ]
+)
+subscription = client.subscribe(filter: filter)
+```
+
+## Filtering by author
+
+You can filter events by their author's pubkey:
+
+```ruby
+filter = Nostr::Filter.new(
+  authors: [
+    # matches events whose (authors) pubkey match these exact IDs
+    'b698043170d580f8ae5bad4ac80b1fdb508e957f0bbffe97f2a8915fa8b34070',
+    '51f853ff4894b062950e46ebed8c1c7015160f8173994414a96dd286f65f0f49',
+  ]
+)
+subscription = client.subscribe(filter: filter)
+```
+
+## Filtering by kind
+
+You can filter events by their kind:
+
+```ruby
+filter = Nostr::Filter.new(
+  kinds: [
+    # matches events whose kind is TEXT_NOTE
+    Nostr::EventKind::TEXT_NOTE,
+    # and matches events whose kind is CONTACT_LIST
+    Nostr::EventKind::CONTACT_LIST,
+  ]
+)
+subscription = client.subscribe(filter: filter)
+```
+
+## Filtering by referenced event
+
+You can filter events by the events they reference (in their `e` tag):
+
+```ruby
+filter = Nostr::Filter.new(
+  e: [
+    # matches events that reference other events whose ids match these exact IDs
+    'f111593a72cc52a7f0978de5ecf29b4653d0cf539f1fa50d2168fc1dc8280e52',
+    'f1f9b0996d4ff1bf75e79e4cc8577c89eb633e68415c7faf74cf17a07bf80bd8',
+  ]
+)
+subscription = client.subscribe(filter: filter)
+```
+
+## Filtering by referenced pubkey
+
+You can filter events by the pubkeys they reference (in their `p` tag):
+
+```ruby
+filter = Nostr::Filter.new(
+  p: [
+    # matches events that reference other pubkeys that match these exact IDs
+    'b698043170d580f8ae5bad4ac80b1fdb508e957f0bbffe97f2a8915fa8b34070',
+    '51f853ff4894b062950e46ebed8c1c7015160f8173994414a96dd286f65f0f49',
+  ]
+)
+subscription = client.subscribe(filter: filter)
+```
+
+## Filtering by timestamp
+
+You can filter events by their timestamp:
+
+```ruby
+filter = Nostr::Filter.new(
+  since: 1230981305, # matches events that are newer than this timestamp
+  until: 1292190341, # matches events that are older than this timestamp
+)
+subscription = client.subscribe(filter: filter)
+```
+
+## Limiting the number of events
+
+You can limit the number of events received:
+
+```ruby
+filter = Nostr::Filter.new(
+  limit: 420, # matches at most 420 events
+)
+subscription = client.subscribe(filter: filter)
+```
+
+## Combining filters
+
+You can combine filters. For example, to match `5` text note events that are newer than `1230981305` from the author
+`ae00f88a885ce76afad5cbb2459ef0dcf0df0907adc6e4dac16e1bfbd7074577`:
+
+```ruby
+filter = Nostr::Filter.new(
+  authors: ['ae00f88a885ce76afad5cbb2459ef0dcf0df0907adc6e4dac16e1bfbd7074577'],
+  kinds: [Nostr::EventKind::TEXT_NOTE],
+  since: 1230981305,
+  limit: 5,
+)
+subscription = client.subscribe(filter: filter)
+```
--- a/docs/subscriptions/updating-a-subscription.md
+++ b/docs/subscriptions/updating-a-subscription.md
@@ -0,0 +1,4 @@
+# Updating a subscription
+
+Updating a subscription is done by creating a new subscription with the same id as the previous one. See
+[creating a subscription](./creating-a-subscription.md) for more information.
--- a/lib/nostr.rb
+++ b/lib/nostr.rb
@@ -1,5 +1,7 @@
 # frozen_string_literal: true

+require_relative 'nostr/errors'
+require_relative 'nostr/bech32'
 require_relative 'nostr/crypto'
 require_relative 'nostr/version'
 require_relative 'nostr/keygen'
@@ -7,12 +9,16 @@ require_relative 'nostr/client_message_type'
 require_relative 'nostr/filter'
 require_relative 'nostr/subscription'
 require_relative 'nostr/relay'
+require_relative 'nostr/relay_message_type'
 require_relative 'nostr/key_pair'
 require_relative 'nostr/event_kind'
 require_relative 'nostr/event'
 require_relative 'nostr/events/encrypted_direct_message'
 require_relative 'nostr/client'
 require_relative 'nostr/user'
+require_relative 'nostr/key'
+require_relative 'nostr/private_key'
+require_relative 'nostr/public_key'

 # Encapsulates all the gem's logic
 module Nostr
--- a/lib/nostr/bech32.rb
+++ b/lib/nostr/bech32.rb
@@ -0,0 +1,203 @@
+# frozen_string_literal: true
+
+require 'bech32'
+require 'bech32/nostr'
+require 'bech32/nostr/entity'
+
+module Nostr
+  # Bech32 encoding and decoding
+  #
+  # @api public
+  #
+  module Bech32
+    # Decodes a bech32-encoded string
+    #
+    # @api public
+    #
+    # @example
+    #   bech32_value = 'npub10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qzvjptg'
+    #   Nostr::Bech32.decode(bech32_value) # => ['npub', '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d8...']
+    #
+    # @param [String] bech32_value The bech32-encoded string to decode
+    #
+    # @return [Array<String, String>] The human readable part and the data
+    #
+    def self.decode(bech32_value)
+      entity = ::Bech32::Nostr::NIP19.decode(bech32_value)
+
+      case entity
+      in ::Bech32::Nostr::BareEntity
+        [entity.hrp, entity.data]
+      in ::Bech32::Nostr::TLVEntity
+        [entity.hrp, entity.entries]
+      end
+    end
+
+    # Encodes data into a bech32 string
+    #
+    # @api public
+    #
+    # @example
+    #   Nostr::Bech32.encode(hrp: 'npub', data: '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e')
+    #   # => 'npub10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qzvjptg'
+    #
+    # @param [String] hrp The human readable part (npub, nsec, nprofile, nrelay, nevent, naddr, etc)
+    # @param [String] data The data to encode
+    #
+    # @return [String] The bech32-encoded string
+    #
+    def self.encode(hrp:, data:)
+      ::Bech32::Nostr::BareEntity.new(hrp, data).encode
+    end
+
+    # Encodes a hex-encoded public key into a bech32 string
+    #
+    # @api public
+    #
+    # @example
+    #   Nostr::Bech32.npub_encode('7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e')
+    #   # => 'npub10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qzvjptg'
+    #
+    # @param [String] npub The public key to encode
+    #
+    # @see Nostr::Bech32#encode
+    # @see Nostr::PublicKey#to_bech32
+    # @see Nostr::PrivateKey#to_bech32
+    #
+    # @return [String] The bech32-encoded string
+    #
+    def self.npub_encode(npub)
+      encode(hrp: 'npub', data: npub)
+    end
+
+    # Encodes a hex-encoded private key into a bech32 string
+    #
+    # @api public
+    #
+    # @example
+    #   Nostr::Bech32.nsec_encode('7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e')
+    #   # => 'nsec10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qzvjptg'
+    #
+    # @param [String] nsec The private key to encode
+    #
+    # @see Nostr::Bech32#encode
+    # @see Nostr::PrivateKey#to_bech32
+    # @see Nostr::PublicKey#to_bech32
+    #
+    # @return [String] The bech32-encoded string
+    #
+    def self.nsec_encode(nsec)
+      encode(hrp: 'nsec', data: nsec)
+    end
+
+    # Encodes an address into a bech32 string
+    #
+    # @api public
+    #
+    # @example
+    #   naddr = Nostr::Bech32.naddr_encode(
+    #     pubkey: '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e',
+    #     relays: ['wss://relay.damus.io', 'wss://nos.lol'],
+    #     kind: Nostr::EventKind::TEXT_NOTE,
+    #     identifier: 'damus'
+    #   )
+    #   naddr # => 'naddr1qgs8ul5ug253hlh3n75jne0a5xmjur4urfxpzst88cnegg6ds6ka7ns...'
+    #
+    # @param [PublicKey] pubkey The public key to encode
+    # @param [Array<String>] relays The relays to encode
+    # @param [String] kind The kind of address to encode
+    # @param [String] identifier The identifier of the address to encode
+    #
+    # @return [String] The bech32-encoded string
+    #
+    def self.naddr_encode(pubkey:, relays: [], kind: nil, identifier: nil)
+      entry_relays = relays.map do |relay_url|
+        ::Bech32::Nostr::TLVEntry.new(::Bech32::Nostr::TLVEntity::TYPE_RELAY, relay_url)
+      end
+
+      pubkey_entry = ::Bech32::Nostr::TLVEntry.new(::Bech32::Nostr::TLVEntity::TYPE_AUTHOR, pubkey)
+      kind_entry = ::Bech32::Nostr::TLVEntry.new(::Bech32::Nostr::TLVEntity::TYPE_KIND, kind)
+      identifier_entry = ::Bech32::Nostr::TLVEntry.new(::Bech32::Nostr::TLVEntity::TYPE_SPECIAL, identifier)
+
+      entries = [pubkey_entry, *entry_relays, kind_entry, identifier_entry].compact
+      entity = ::Bech32::Nostr::TLVEntity.new(::Bech32::Nostr::NIP19::HRP_EVENT_COORDINATE, entries)
+      entity.encode
+    end
+
+    # Encodes an event into a bech32 string
+    #
+    # @api public
+    #
+    # @example
+    #   nevent = Nostr::Bech32.nevent_encode(
+    #     id: '0fdb90f8e234d3400edafdd26d493f12efc0d7de2c6f9f21f997847d33ad2ea3',
+    #     relays: ['wss://relay.damus.io', 'wss://nos.lol'],
+    #     kind: Nostr::EventKind::TEXT_NOTE,
+    #   )
+    #   nevent # => 'nevent1qgsqlkuslr3rf56qpmd0m5ndfyl39m7q6l0zcmuly8ue0pra...'
+    #
+    # @param [PublicKey] id The id the event to encode
+    # @param [Array<String>] relays The relays to encode
+    # @param [String] kind The kind of event to encode
+    #
+    # @return [String] The bech32-encoded string
+    #
+    def self.nevent_encode(id:, relays: [], kind: nil)
+      entry_relays = relays.map do |relay_url|
+        ::Bech32::Nostr::TLVEntry.new(::Bech32::Nostr::TLVEntity::TYPE_RELAY, relay_url)
+      end
+
+      id_entry = ::Bech32::Nostr::TLVEntry.new(::Bech32::Nostr::TLVEntity::TYPE_AUTHOR, id)
+      kind_entry = ::Bech32::Nostr::TLVEntry.new(::Bech32::Nostr::TLVEntity::TYPE_KIND, kind)
+
+      entries = [id_entry, *entry_relays, kind_entry].compact
+      entity = ::Bech32::Nostr::TLVEntity.new(::Bech32::Nostr::NIP19::HRP_EVENT, entries)
+      entity.encode
+    end
+
+    # Encodes a profile into a bech32 string
+    #
+    # @api public
+    #
+    # @example
+    #   nprofile = Nostr::Bech32.nprofile_encode(
+    #     pubkey: '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e',
+    #     relays: ['wss://relay.damus.io', 'wss://nos.lol']
+    #   )
+    #
+    # @param [PublicKey] pubkey The public key to encode
+    # @param [Array<String>] relays The relays to encode
+    #
+    # @return [String] The bech32-encoded string
+    #
+    def self.nprofile_encode(pubkey:, relays: [])
+      entry_relays = relays.map do |relay_url|
+        ::Bech32::Nostr::TLVEntry.new(::Bech32::Nostr::TLVEntity::TYPE_RELAY, relay_url)
+      end
+
+      pubkey_entry = ::Bech32::Nostr::TLVEntry.new(::Bech32::Nostr::TLVEntity::TYPE_SPECIAL, pubkey)
+      entries = [pubkey_entry, *entry_relays].compact
+      entity = ::Bech32::Nostr::TLVEntity.new(::Bech32::Nostr::NIP19::HRP_PROFILE, entries)
+      entity.encode
+    end
+
+    # Encodes a relay URL into a bech32 string
+    #
+    # @api public
+    #
+    # @example
+    #   nrelay = Nostr::Bech32.nrelay_encode('wss://relay.damus.io')
+    #   nrelay # => 'nrelay1qq28wumn8ghj7un9d3shjtnyv9kh2uewd9hsc5zt2x'
+    #
+    # @param [String] relay_url The relay url to encode
+    #
+    # @return [String] The bech32-encoded string
+    #
+    def self.nrelay_encode(relay_url)
+      relay_entry = ::Bech32::Nostr::TLVEntry.new(::Bech32::Nostr::TLVEntity::TYPE_SPECIAL, relay_url)
+
+      entity = ::Bech32::Nostr::TLVEntity.new(::Bech32::Nostr::NIP19::HRP_RELAY, [relay_entry])
+      entity.encode
+    end
+  end
+end
--- a/lib/nostr/client.rb
+++ b/lib/nostr/client.rb
@@ -74,7 +74,8 @@ module Nostr
    # @example Subscribing to all events created after a certain time
    #   subscription = client.subscribe(filter: Nostr::Filter.new(since: 1230981305))
    #
-    # @param subscription_id [String] The subscription id. A random string.
+    # @param subscription_id [String] The subscription id. An arbitrary, non-empty string of max length 64
+    #   chars used to represent a subscription.
    # @param filter [Filter] A set of attributes that represent the events that the client is interested in.
    #
    # @return [Subscription] The subscription object
--- a/lib/nostr/crypto.rb
+++ b/lib/nostr/crypto.rb
@@ -30,8 +30,8 @@ module Nostr
    #   encrypted = crypto.encrypt_text(sender_private_key, recipient_public_key, 'Feedback appreciated. Now pay $8')
    #   encrypted # => "wrYQaHDfpOEvyJELSCg1vzsywmlJTz8NqH03eFW44s8iQs869jtSb26Lr4s23gmY?iv=v38vAJ3LlJAGZxbmWU4qAg=="
    #
-    # @param sender_private_key [String] 32-bytes hex-encoded private key of the creator.
-    # @param recipient_public_key [String] 32-bytes hex-encoded public key of the recipient.
+    # @param sender_private_key [PrivateKey] 32-bytes hex-encoded private key of the creator.
+    # @param recipient_public_key [PublicKey] 32-bytes hex-encoded public key of the recipient.
    # @param plain_text [String] The text to be encrypted
    #
    # @return [String] Encrypted text.
@@ -54,14 +54,18 @@ module Nostr
    #   encrypted # => "wrYQaHDfpOEvyJELSCg1vzsywmlJTz8NqH03eFW44s8iQs869jtSb26Lr4s23gmY?iv=v38vAJ3LlJAGZxbmWU4qAg=="
    #   decrypted = crypto.decrypt_text(recipient_private_key, sender_public_key, encrypted)
    #
-    # @param sender_public_key [String] 32-bytes hex-encoded public key of the message creator.
-    # @param recipient_private_key [String] 32-bytes hex-encoded public key of the recipient.
+    # @param sender_public_key [PublicKey] 32-bytes hex-encoded public key of the message creator.
+    # @param recipient_private_key [PrivateKey] 32-bytes hex-encoded public key of the recipient.
    # @param encrypted_text [String] The text to be decrypted
    #
    # @return [String] Decrypted text.
    #
    def decrypt_text(recipient_private_key, sender_public_key, encrypted_text)
      base64_encoded_text, iv = encrypted_text.split('?iv=')
+
+      # Ensure iv and base64_encoded_text are not nil
+      return '' unless iv && base64_encoded_text
+
      cipher = OpenSSL::Cipher.new(CIPHER_ALGORITHM).decrypt
      cipher.iv = Base64.decode64(iv)
      cipher.key = compute_shared_key(recipient_private_key, sender_public_key)
@@ -80,7 +84,7 @@ module Nostr
    #   event.sig # => a signature
    #
    # @param event [Event] The event to be signed
-    # @param private_key [String] 32-bytes hex-encoded private key.
+    # @param private_key [PrivateKey] 32-bytes hex-encoded private key.
    #
    # @return [Event] An unsigned event.
    #
@@ -103,8 +107,8 @@ module Nostr
    #
    # @api private
    #
-    # @param private_key [String] 32-bytes hex-encoded private key.
-    # @param public_key [String] 32-bytes hex-encoded public key.
+    # @param private_key [PrivateKey] 32-bytes hex-encoded private key.
+    # @param public_key [PublicKey] 32-bytes hex-encoded public key.
    #
    # @return [String] A shared key used in the event's content encryption and decryption.
    #
--- a/lib/nostr/errors.rb
+++ b/lib/nostr/errors.rb
@@ -0,0 +1,8 @@
+# frozen_string_literal: true
+
+require_relative 'errors/error'
+require_relative 'errors/key_validation_error'
+require_relative 'errors/invalid_hrp_error'
+require_relative 'errors/invalid_key_type_error'
+require_relative 'errors/invalid_key_length_error'
+require_relative 'errors/invalid_key_format_error'
--- a/lib/nostr/errors/error.rb
+++ b/lib/nostr/errors/error.rb
@@ -0,0 +1,7 @@
+# frozen_string_literal: true
+
+module Nostr
+  # Base error class
+  class Error < StandardError
+  end
+end
--- a/lib/nostr/errors/invalid_hrp_error.rb
+++ b/lib/nostr/errors/invalid_hrp_error.rb
@@ -0,0 +1,21 @@
+# frozen_string_literal: true
+
+module Nostr
+  # Raised when the human readable part of a Bech32 string is invalid
+  #
+  # @api public
+  #
+  class InvalidHRPError < KeyValidationError
+    # Initializes the error
+    #
+    # @example
+    #   InvalidHRPError.new('example wrong hrp', 'nsec')
+    #
+    # @param given_hrp [String] The given human readable part of the Bech32 string
+    # @param allowed_hrp [String] The allowed human readable part of the Bech32 string
+    #
+    def initialize(given_hrp, allowed_hrp)
+      super("Invalid hrp: #{given_hrp}. The allowed hrp value for this kind of entity is '#{allowed_hrp}'.")
+    end
+  end
+end
--- a/lib/nostr/errors/invalid_key_format_error.rb
+++ b/lib/nostr/errors/invalid_key_format_error.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+module Nostr
+  # Raised when the private key is in an invalid format
+  #
+  # @api public
+  #
+  class InvalidKeyFormatError < KeyValidationError
+    # Initializes the error
+    #
+    # @example
+    #   InvalidKeyFormatError.new('private'')
+    #
+    # @param [String] key_kind The kind of key that is invalid (public or private)
+    #
+    def initialize(key_kind)
+      super("Only lowercase hexadecimal characters are allowed in #{key_kind} keys.")
+    end
+  end
+end
--- a/lib/nostr/errors/invalid_key_length_error.rb
+++ b/lib/nostr/errors/invalid_key_length_error.rb
@@ -0,0 +1,20 @@
+# frozen_string_literal: true
+
+module Nostr
+  # Raised when the private key's length is not 64 characters
+  #
+  # @api public
+  #
+  class InvalidKeyLengthError < KeyValidationError
+    # Initializes the error
+    #
+    # @example
+    #   InvalidKeyLengthError.new('private'')
+    #
+    # @param [String] key_kind The kind of key that is invalid (public or private)
+    #
+    def initialize(key_kind)
+      super("Invalid #{key_kind} key length. It should have 64 characters.")
+    end
+  end
+end
--- a/lib/nostr/errors/invalid_key_type_error.rb
+++ b/lib/nostr/errors/invalid_key_type_error.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module Nostr
+  # Raised when the private key is not a string
+  #
+  # @api public
+  #
+  class InvalidKeyTypeError < KeyValidationError
+    # Initializes the error
+    #
+    # @example
+    #   InvalidKeyTypeError.new('private'')
+    #
+    # @param [String] key_kind The kind of key that is invalid (public or private)
+    #
+    def initialize(key_kind) = super("Invalid #{key_kind} key type")
+  end
+end
--- a/lib/nostr/errors/key_validation_error.rb
+++ b/lib/nostr/errors/key_validation_error.rb
@@ -0,0 +1,6 @@
+# frozen_string_literal: true
+
+module Nostr
+  # Base class for all key validation errors
+  class KeyValidationError < Error; end
+end
--- a/lib/nostr/event.rb
+++ b/lib/nostr/event.rb
@@ -128,7 +128,6 @@ module Nostr
      id: nil,
      sig: nil
    )
-
      @id = id
      @sig = sig
      @pubkey = pubkey
@@ -160,11 +159,11 @@ module Nostr
    #   pubkey = '48df4af6e240ac5f7c5de89bf5941b249880be0e87d03685b178ccb1a315f52e'
    #   event.add_pubkey_reference(pubkey)
    #
-    # @param pubkey [String] 32-bytes hex-encoded public key.
+    # @param pubkey [PublicKey] 32-bytes hex-encoded public key.
    #
    # @return [Array<String>] The event's updated list of tags
    #
-    def add_pubkey_reference(pubkey) = tags.push(['p', pubkey])
+    def add_pubkey_reference(pubkey) = tags.push(['p', pubkey.to_s])

    # Signs an event with the user's private key
    #
@@ -173,7 +172,7 @@ module Nostr
    # @example Signing an event
    #   event.sign(private_key)
    #
-    # @param private_key [String] 32-bytes hex-encoded private key.
+    # @param private_key [PrivateKey] 32-bytes hex-encoded private key.
    #
    # @return [Event] A signed event.
    #
--- a/lib/nostr/events/encrypted_direct_message.rb
+++ b/lib/nostr/events/encrypted_direct_message.rb
@@ -26,8 +26,9 @@ module Nostr
      # )
      #
      # @param plain_text [String] The +content+ of the encrypted message.
-      # @param sender_private_key [String] 32-bytes hex-encoded private key of the message's author.
-      # @param recipient_public_key [String] 32-bytes hex-encoded public key of the recipient of the encrypted message.
+      # @param sender_private_key [PrivateKey] 32-bytes hex-encoded private key of the message's author.
+      # @param recipient_public_key [PublicKey] 32-bytes hex-encoded public key of the recipient of the encrypted
+      #  message.
      # @param previous_direct_message [String] 32-bytes hex-encoded id identifying the previous message in a
      # conversation or a message we are explicitly replying to (such that contextual, more organized conversations
      # may happen
@@ -43,7 +44,7 @@ module Nostr
          pubkey: sender_public_key,
          kind: Nostr::EventKind::ENCRYPTED_DIRECT_MESSAGE,
          content: encrypted_content,
-          )
+        )

        add_pubkey_reference(recipient_public_key)
        add_event_reference(previous_direct_message) if previous_direct_message
--- a/lib/nostr/filter.rb
+++ b/lib/nostr/filter.rb
@@ -3,7 +3,7 @@
 module Nostr
  # A filter determines what events will be sent in a subscription.
  class Filter
-    # A list of event ids or prefixes
+    # A list of event ids
    #
    # @api public
    #
@@ -14,7 +14,7 @@ module Nostr
    #
    attr_reader :ids

-    # A list of pubkeys or prefixes, the pubkey of an event must be one of these
+    # A list of pubkeys, the pubkey of an event must be one of these
    #
    # @api public
    #
@@ -107,8 +107,8 @@ module Nostr
    #   )
    #
    # @param kwargs [Hash]
-    # @option kwargs [Array<String>, nil] ids A list of event ids or prefixes
-    # @option kwargs [Array<String>, nil] authors A list of pubkeys or prefixes, the pubkey of an event must be one
+    # @option kwargs [Array<String>, nil] ids A list of event ids
+    # @option kwargs [Array<String>, nil] authors A list of pubkeys, the pubkey of an event must be one
    # of these
    # @option kwargs [Array<Integer>, nil] kinds A list of a kind numbers
    # @option kwargs [Array<String>, nil] e A list of event ids that are referenced in an "e" tag
--- a/lib/nostr/key.rb
+++ b/lib/nostr/key.rb
@@ -0,0 +1,100 @@
+# frozen_string_literal: true
+
+module Nostr
+  # Abstract class for all keys
+  #
+  # @api private
+  #
+  class Key < String
+    # The regular expression for hexadecimal lowercase characters
+    #
+    # @return [Regexp] The regular expression for hexadecimal lowercase characters
+    #
+    FORMAT = /^[a-f0-9]+$/
+
+    # The length of the key in hex format
+    #
+    # @return [Integer] The length of the key in hex format
+    #
+    LENGTH = 64
+
+    # Instantiates a new key. Can't be used directly because this is an abstract class. Raises a +ValidationError+
+    #
+    # @see Nostr::PrivateKey
+    # @see Nostr::PublicKey
+    #
+    # @param [String] hex_value Hex-encoded value of the key
+    #
+    # @raise [ValidationError]
+    #
+    def initialize(hex_value)
+      validate_hex_value(hex_value)
+
+      super(hex_value)
+    end
+
+    # Instantiates a key from a bech32 string
+    #
+    # @api public
+    #
+    # @example
+    #   bech32_key = 'nsec1vl029mgpspedva04g90vltkh6fvh240zqtv9k0t9af8935ke9laqsnlfe5'
+    #   bech32_key.to_key # => #<Nostr::PublicKey:0x000000010601e3c8 @hex_value="...">
+    #
+    # @raise [Nostr::InvalidHRPError] if the bech32 string is invalid.
+    #
+    # @param [String] bech32_value The bech32 string representation of the key.
+    #
+    # @return [Key] the key.
+    #
+    def self.from_bech32(bech32_value)
+      type, data = Bech32.decode(bech32_value)
+
+      raise InvalidHRPError.new(type, hrp) unless type == hrp
+
+      new(data)
+    end
+
+    # Abstract method to be implemented by subclasses to provide the HRP (npub, nsec)
+    #
+    # @api private
+    #
+    # @return [String] The HRP
+    #
+    def self.hrp
+      raise 'Subclasses must implement this method'
+    end
+
+    # Converts the key to a bech32 string representation
+    #
+    # @api public
+    #
+    # @example Converting a private key to a bech32 string
+    #   public_key = Nostr::PrivateKey.new('67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa')
+    #   public_key.to_bech32 # => 'nsec1vl029mgpspedva04g90vltkh6fvh240zqtv9k0t9af8935ke9laqsnlfe5'
+    #
+    # @example Converting a public key to a bech32 string
+    #   public_key = Nostr::PublicKey.new('7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e')
+    #   public_key.to_bech32 # => 'npub10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qzvjptg'
+    #
+    # @return [String] The bech32 string representation of the key
+    #
+    def to_bech32 = Bech32.encode(hrp: self.class.hrp, data: self)
+
+    protected
+
+    # Validates the hex value during initialization
+    #
+    # @api private
+    #
+    # @param [String] _hex_value The hex value of the key
+    #
+    # @raise [KeyValidationError] When the hex value is invalid
+    #
+    # @return [void]
+    #
+    def validate_hex_value(_hex_value)
+      raise 'Subclasses must implement this method'
+    end
+  end
+end
--- a/lib/nostr/key_pair.rb
+++ b/lib/nostr/key_pair.rb
@@ -10,7 +10,7 @@ module Nostr
    # @example
    #   keypair.private_key # => '893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900'
    #
-    # @return [String]
+    # @return [PrivateKey]
    #
    attr_reader :private_key

@@ -21,7 +21,7 @@ module Nostr
    # @example
    #   keypair.public_key # => '2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558'
    #
-    # @return [String]
+    # @return [PublicKey]
    #
    attr_reader :public_key

@@ -31,16 +31,40 @@ module Nostr
    #
    # @example
    #   keypair = Nostr::KeyPair.new(
-    #     private_key: '893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900',
-    #     public_key: '2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558',
+    #     private_key: Nostr::PrivateKey.new('893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900'),
+    #     public_key: Nostr::PublicKey.new('2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558'),
    #   )
    #
-    # @param private_key [String] 32-bytes hex-encoded private key.
-    # @param public_key [String] 32-bytes hex-encoded public key.
+    # @param private_key [PrivateKey] 32-bytes hex-encoded private key.
+    # @param public_key [PublicKey] 32-bytes hex-encoded public key.
+    #
+    # @raise ArgumentError when the private key is not a +PrivateKey+
+    # @raise ArgumentError when the public key is not a +PublicKey+
    #
    def initialize(private_key:, public_key:)
+      validate_keys(private_key, public_key)
+
      @private_key = private_key
      @public_key = public_key
    end
+
+    private
+
+    # Validates the keys
+    #
+    # @api private
+    #
+    # @param private_key [PrivateKey] 32-bytes hex-encoded private key.
+    # @param public_key [PublicKey] 32-bytes hex-encoded public key.
+    #
+    # @raise ArgumentError when the private key is not a +PrivateKey+
+    # @raise ArgumentError when the public key is not a +PublicKey+
+    #
+    # @return [void]
+    #
+    def validate_keys(private_key, public_key)
+      raise ArgumentError, 'private_key is not an instance of PrivateKey' unless private_key.is_a?(Nostr::PrivateKey)
+      raise ArgumentError, 'public_key is not an instance of PublicKey' unless public_key.is_a?(Nostr::PublicKey)
+    end
  end
 end
--- a/lib/nostr/keygen.rb
+++ b/lib/nostr/keygen.rb
@@ -44,10 +44,11 @@ module Nostr
    #   private_key = keygen.generate_private_key
    #   private_key # => '893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900'
    #
-    # @return [String] A 32-bytes hex-encoded private key.
+    # @return [PrivateKey] A 32-bytes hex-encoded private key.
    #
    def generate_private_key
-      (SecureRandom.random_number(group.order - 1) + 1).to_s(16)
+      hex_value = (SecureRandom.random_number(group.order - 1) + 1).to_s(16).rjust(64, '0')
+      PrivateKey.new(hex_value)
    end

    # Extracts a public key from a private key
@@ -59,10 +60,36 @@ module Nostr
    #   public_key = keygen.extract_public_key(private_key)
    #   public_key # => '2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558'
    #
-    # @return [String] A 32-bytes hex-encoded public key.
+    # @param [PrivateKey] private_key A 32-bytes hex-encoded private key.
+    #
+    # @raise [ArgumentError] if the private key is not an instance of +PrivateKey+
+    #
+    # @return [PublicKey] A 32-bytes hex-encoded public key.
    #
    def extract_public_key(private_key)
-      group.generator.multiply_by_scalar(private_key.to_i(16)).x.to_s(16).rjust(64, '0')
+      validate_private_key(private_key)
+      hex_value = group.generator.multiply_by_scalar(private_key.to_i(16)).x.to_s(16).rjust(64, '0')
+      PublicKey.new(hex_value)
+    end
+
+    # Builds a key pair from an existing private key
+    #
+    # @api public
+    #
+    # @example
+    #   private_key = Nostr::PrivateKey.new('893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900')
+    #   keygen.get_key_pair_from_private_key(private_key)
+    #
+    # @param private_key [PrivateKey] 32-bytes hex-encoded private key.
+    #
+    # @raise [ArgumentError] if the private key is not an instance of +PrivateKey+
+    #
+    # @return [Nostr::KeyPair]
+    #
+    def get_key_pair_from_private_key(private_key)
+      validate_private_key(private_key)
+      public_key = extract_public_key(private_key)
+      KeyPair.new(private_key:, public_key:)
    end

    private
@@ -74,5 +101,17 @@ module Nostr
    # @return [ECDSA::Group]
    #
    attr_reader :group
+
+    # Validates that the private key is an instance of +PrivateKey+
+    #
+    # @api private
+    #
+    # @raise [ArgumentError] if the private key is not an instance of +PrivateKey+
+    #
+    # @return [void]
+    #
+    def validate_private_key(private_key)
+      raise ArgumentError, 'private_key is not an instance of PrivateKey' unless private_key.is_a?(Nostr::PrivateKey)
+    end
  end
 end
--- a/lib/nostr/private_key.rb
+++ b/lib/nostr/private_key.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+module Nostr
+  # 32-bytes lowercase hex-encoded private key
+  class PrivateKey < Key
+    # Human-readable part of the Bech32 encoded address
+    #
+    # @api private
+    #
+    # @return [String] The human-readable part of the Bech32 encoded address
+    #
+    def self.hrp
+      'nsec'
+    end
+
+    private
+
+    # Validates the hex value of the private key
+    #
+    # @api private
+    #
+    # @param [String] hex_value The private key in hex format
+    #
+    # @raise InvalidKeyTypeError when the private key is not a string
+    # @raise InvalidKeyLengthError when the private key's length is not 64 characters
+    # @raise InvalidKeyFormatError when the private key is in an invalid format
+    #
+    # @return [void]
+    #
+    def validate_hex_value(hex_value)
+      raise InvalidKeyTypeError, 'private'   unless hex_value.is_a?(String)
+      raise InvalidKeyLengthError, 'private' unless hex_value.size == Key::LENGTH
+      raise InvalidKeyFormatError, 'private' unless hex_value.match(Key::FORMAT)
+    end
+  end
+end
--- a/lib/nostr/public_key.rb
+++ b/lib/nostr/public_key.rb
@@ -0,0 +1,36 @@
+# frozen_string_literal: true
+
+module Nostr
+  # 32-bytes lowercase hex-encoded public key
+  class PublicKey < Key
+    # Human-readable part of the Bech32 encoded address
+    #
+    # @api private
+    #
+    # @return [String] The human-readable part of the Bech32 encoded address
+    #
+    def self.hrp
+      'npub'
+    end
+
+    private
+
+    # Validates the hex value of the public key
+    #
+    # @api private
+    #
+    # @param [String] hex_value The public key in hex format
+    #
+    # @raise InvalidKeyTypeError when the public key is not a string
+    # @raise InvalidKeyLengthError when the public key's length is not 64 characters
+    # @raise InvalidKeyFormatError when the public key is in an invalid format
+    #
+    # @return [void]
+    #
+    def validate_hex_value(hex_value)
+      raise InvalidKeyTypeError, 'public' unless hex_value.is_a?(String)
+      raise InvalidKeyLengthError, 'public' unless hex_value.size == Key::LENGTH
+      raise InvalidKeyFormatError, 'public' unless hex_value.match(Key::FORMAT)
+    end
+  end
+end
--- a/lib/nostr/relay_message_type.rb
+++ b/lib/nostr/relay_message_type.rb
@@ -0,0 +1,18 @@
+# frozen_string_literal: true
+
+module Nostr
+  # Clients can send 4 types of messages, which must be JSON arrays
+  module RelayMessageType
+    # @return [String] Used to notify clients all stored events have been sent
+    EOSE = 'EOSE'
+
+    # @return [String] Used to send events requested to clients
+    EVENT = 'EVENT'
+
+    # @return [String] Used to send human-readable messages to clients
+    NOTICE = 'NOTICE'
+
+    # @return [String] Used to notify clients if an EVENT was successful
+    OK = 'OK'
+  end
+end
--- a/lib/nostr/subscription.rb
+++ b/lib/nostr/subscription.rb
@@ -5,7 +5,7 @@ require 'securerandom'
 module Nostr
  # A subscription the result of a request to receive events from a relay
  class Subscription
-    # A random string that should be used to represent a subscription
+    # An arbitrary, non-empty string of max length 64 chars used to represent a subscription
    #
    # @api public
    #
@@ -41,7 +41,7 @@ module Nostr
    # @example Subscribing to all events created after a certain time
    #   subscription = Nostr::Subscription.new(filter: Nostr::Filter.new(since: 1230981305))
    #
-    # @param id [String] A random string that should be used to represent a subscription
+    # @param id [String] An arbitrary, non-empty string of max length 64 chars used to represent a subscription
    # @param filter [Filter] An object that determines what events will be sent in that subscription
    #
    def initialize(filter:, id: SecureRandom.hex)
--- a/lib/nostr/user.rb
+++ b/lib/nostr/user.rb
@@ -47,17 +47,26 @@ module Nostr
    #     content: 'Your feedback is appreciated, now pay $8'
    #   )
    #
-    # @param event_attributes [Hash]
-    # @option event_attributes [String] :pubkey 32-bytes hex-encoded public key of the event creator.
-    # @option event_attributes [Integer] :created_at Date of the creation of the vent. A UNIX timestamp, in seconds.
-    # @option event_attributes [Integer] :kind The kind of the event. An integer from 0 to 3.
-    # @option event_attributes [Array<Array>] :tags  An array of tags. Each tag is an array of strings.
-    # @option event_attributes [String] :content Arbitrary string.
+    # @param created_at [Integer] Date of the creation of the vent. A UNIX timestamp, in seconds.
+    # @param kind [Integer] The kind of the event. An integer from 0 to 3.
+    # @param tags [Array<Array>] An array of tags. Each tag is an array of strings.
+    # @param content [String] Arbitrary string.
    #
    # @return [Event]
    #
-    def create_event(event_attributes)
-      event = Event.new(**event_attributes.merge(pubkey: keypair.public_key))
+    def create_event(
+      kind:,
+      content:,
+      created_at: Time.now.to_i,
+      tags: []
+    )
+      event = Event.new(
+        pubkey: keypair.public_key,
+        kind:,
+        content:,
+        created_at:,
+        tags:
+      )
      event.sign(keypair.private_key)
    end
  end
--- a/lib/nostr/version.rb
+++ b/lib/nostr/version.rb
@@ -2,5 +2,5 @@

 module Nostr
  # The version of the gem
-  VERSION = '0.4.0'
+  VERSION = '0.5.0'
 end
--- a/nostr.gemspec
+++ b/nostr.gemspec
@@ -10,7 +10,7 @@ Gem::Specification.new do |spec|

  spec.summary = 'Client and relay implementation of the Nostr protocol.'
  spec.description = 'Client and relay implementation of the Nostr protocol.'
-  spec.homepage = 'https://github.com/wilsonsilva/nostr'
+  spec.homepage = 'https://nostr-ruby.com/'
  spec.license = 'MIT'
  spec.required_ruby_version = '>= 3.2.0'
  spec.metadata['rubygems_mfa_required'] = 'true'
@@ -31,8 +31,8 @@ Gem::Specification.new do |spec|
  spec.executables = spec.files.grep(%r{\Aexe/}) { |f| File.basename(f) }
  spec.require_paths = ['lib']

-  spec.add_dependency 'bech32', '~> 1.3'
-  spec.add_dependency 'bip-schnorr', '~> 0.4'
+  spec.add_dependency 'bech32', '~> 1.4'
+  spec.add_dependency 'bip-schnorr', '~> 0.6'
  spec.add_dependency 'ecdsa', '~> 1.2'
  spec.add_dependency 'event_emitter', '~> 0.2'
  spec.add_dependency 'faye-websocket', '~> 0.11'
@@ -47,17 +47,17 @@ Gem::Specification.new do |spec|
  spec.add_development_dependency 'guard-rubocop', '~> 1.5'
  spec.add_development_dependency 'overcommit', '~> 0.59'
  spec.add_development_dependency 'pry', '~> 0.14'
-  spec.add_development_dependency 'puma', '~> 5.6'
+  spec.add_development_dependency 'puma', '~> 6.4'
  spec.add_development_dependency 'rack', '~> 3.0'
-  spec.add_development_dependency 'rake', '~> 13.0'
-  spec.add_development_dependency 'rbs', '~> 2.8'
+  spec.add_development_dependency 'rake', '~> 13.1'
+  spec.add_development_dependency 'rbs', '~> 3.3'
  spec.add_development_dependency 'rspec', '~> 3.12'
-  spec.add_development_dependency 'rubocop', '~> 1.42'
+  spec.add_development_dependency 'rubocop', '~> 1.57'
  spec.add_development_dependency 'rubocop-rake', '~> 0.6'
-  spec.add_development_dependency 'rubocop-rspec', '2.16'
+  spec.add_development_dependency 'rubocop-rspec', '2.25'
  spec.add_development_dependency 'simplecov', '= 0.17'
  spec.add_development_dependency 'simplecov-console', '~> 0.9'
-  spec.add_development_dependency 'steep', '~> 1.3'
+  spec.add_development_dependency 'steep', '~> 1.6'
  spec.add_development_dependency 'typeprof', '~> 0.21'
  spec.add_development_dependency 'yard', '~> 0.9'
  spec.add_development_dependency 'yard-junk', '~> 0.0.9'
--- a/sig/nostr/bech32.rbs
+++ b/sig/nostr/bech32.rbs
@@ -0,0 +1,14 @@
+module Nostr
+  module Bech32
+    # Perhaps a bug in RBS/Steep. +decode+ and +encode+ are not recognized as public class methods.
+    def self?.decode: (String data) -> [String, String]
+    def self?.encode: (hrp: String, data: String) -> String
+
+    def naddr_encode: (pubkey: PublicKey, ?relays: Array[String], ?kind: Integer, ?identifier: String) -> String
+    def nevent_encode: (id: PublicKey, ?relays: Array[String], ?kind: Integer) -> String
+    def nprofile_encode: (pubkey: PublicKey, ?relays: Array[String]) -> String
+    def npub_encode: (String npub) -> String
+    def nrelay_encode: (String nrelay) -> String
+    def nsec_encode: (String nsec) -> String
+  end
+end
--- a/sig/nostr/client.rbs
+++ b/sig/nostr/client.rbs
@@ -5,16 +5,16 @@ module Nostr
    def initialize: -> void
    def connect: (Relay relay) -> Thread
    def subscribe: (?subscription_id: String, ?filter: Filter) -> Subscription
-    def unsubscribe: (String subscription_id) -> untyped
+    def unsubscribe: (String subscription_id) -> void
    def publish: (Event event) -> untyped

    private

    attr_reader subscriptions: Hash[String, Subscription]
-    attr_reader parent_to_child_channel: untyped
-    attr_reader child_to_parent_channel: untyped
+    attr_reader parent_to_child_channel: EventMachine::Channel
+    attr_reader child_to_parent_channel: EventMachine::Channel

-    def execute_within_an_em_thread: { -> untyped } -> Thread
-    def initialize_channels: -> untyped
+    def execute_within_an_em_thread: { -> void } -> Thread
+    def initialize_channels: -> void
  end
 end
--- a/sig/nostr/crypto.rbs
+++ b/sig/nostr/crypto.rbs
@@ -1,16 +1,16 @@
 module Nostr
  class Crypto
-    BN_BASE: Integer
+    BN_BASE: 0 | 2 | 10 | 16
    CIPHER_CURVE: String
    CIPHER_ALGORITHM: String

-    def encrypt_text: (String, String, String) -> String
-    def decrypt_text: (String, String, String) -> String
-    def sign_event: (Event, String) -> Event
+    def encrypt_text: (PrivateKey, PublicKey, String) -> String
+    def decrypt_text: (PrivateKey, PublicKey, String) -> String
+    def sign_event: (Event, PrivateKey) -> Event

    private

-    def compute_shared_key: (String, String) -> String
+    def compute_shared_key: (PrivateKey, PublicKey) -> String
    def hash_event:(Event) -> String
  end
 end
--- a/sig/nostr/errors/error.rbs
+++ b/sig/nostr/errors/error.rbs
@@ -0,0 +1,4 @@
+module Nostr
+  class Error < StandardError
+  end
+end
--- a/sig/nostr/errors/invalid_hrb_error.rbs
+++ b/sig/nostr/errors/invalid_hrb_error.rbs
@@ -0,0 +1,6 @@
+module Nostr
+  class InvalidHRPError < KeyValidationError
+    def initialize: (String, String) -> void
+  end
+end
+
--- a/sig/nostr/errors/invalid_key_format_error.rbs
+++ b/sig/nostr/errors/invalid_key_format_error.rbs
@@ -0,0 +1,5 @@
+module Nostr
+  class InvalidKeyFormatError < KeyValidationError
+    def initialize: (String) -> void
+  end
+end
--- a/sig/nostr/errors/invalid_key_length_error.rbs
+++ b/sig/nostr/errors/invalid_key_length_error.rbs
@@ -0,0 +1,5 @@
+module Nostr
+  class InvalidKeyLengthError < KeyValidationError
+    def initialize: (String) -> void
+  end
+end
--- a/sig/nostr/errors/invalid_key_type_error.rbs
+++ b/sig/nostr/errors/invalid_key_type_error.rbs
@@ -0,0 +1,5 @@
+module Nostr
+  class InvalidKeyTypeError < KeyValidationError
+    def initialize: (String) -> void
+  end
+end
--- a/sig/nostr/errors/key_validation_error.rbs
+++ b/sig/nostr/errors/key_validation_error.rbs
@@ -0,0 +1,4 @@
+module Nostr
+  class KeyValidationError < Error
+  end
+end
--- a/sig/nostr/event.rbs
+++ b/sig/nostr/event.rbs
@@ -1,6 +1,6 @@
 module Nostr
  class Event
-    attr_reader pubkey: String
+    attr_reader pubkey: PublicKey
    attr_reader created_at: Integer
    attr_reader kind: Integer
    attr_reader tags: Array[Array[String]]
@@ -9,7 +9,7 @@ module Nostr
    attr_accessor sig: String?|nil

    def initialize: (
-      pubkey: String,
+      pubkey: PublicKey,
      kind: Integer,
      content: String,
      ?created_at: Integer,
@@ -31,9 +31,9 @@ module Nostr
    }
    def ==: (Event other) -> bool

-    def sign:(String) -> Event
+    def sign:(PrivateKey) -> Event

    def add_event_reference: (String) -> Array[Array[String]]
-    def add_pubkey_reference: (String) -> Array[Array[String]]
+    def add_pubkey_reference: (PublicKey) -> Array[Array[String]]
  end
 end
--- a/sig/nostr/events/encrypted_direct_message.rbs
+++ b/sig/nostr/events/encrypted_direct_message.rbs
@@ -3,8 +3,8 @@ module Nostr
    class EncryptedDirectMessage < Event
      def initialize: (
          plain_text: String,
-          sender_private_key: String,
-          recipient_public_key: String,
+          sender_private_key: PrivateKey,
+          recipient_public_key: PublicKey,
          ?previous_direct_message: String|nil
        ) -> void
    end
--- a/sig/nostr/filter.rbs
+++ b/sig/nostr/filter.rbs
@@ -3,23 +3,14 @@ module Nostr
    attr_reader ids: Array[String]
    attr_reader authors: Array[String]
    attr_reader kinds: Array[Integer]
-    attr_reader e: String
-    attr_reader p: String
+    attr_reader e: Array[String]
+    attr_reader p: Array[String]
    attr_reader since: Integer
    attr_reader until: Integer
    attr_reader limit: Integer

    def initialize: (**untyped) -> void
-    def to_h: -> {
-      ids: Array[String],
-      authors: Array[String],
-      kinds: Array[Integer],
-      e: String,
-      p: String,
-      since: Integer,
-      until: Integer,
-      limit: Integer
-    }
+    def to_h: -> Hash[::Symbol, (::Array[::String] | ::Array[::Integer] | ::Integer)]
    def ==: (Filter other) -> bool
  end
 end
--- a/sig/nostr/key.rbs
+++ b/sig/nostr/key.rbs
@@ -0,0 +1,16 @@
+module Nostr
+  class Key < String
+    FORMAT: Regexp
+    LENGTH: int
+
+    def self.from_bech32: (String) -> Key
+    def self.hrp: -> String
+
+    def initialize: (String) -> void
+    def to_bech32: -> String
+
+    private
+
+    def validate_hex_value: (String) -> nil
+  end
+end
--- a/sig/nostr/key_pair.rbs
+++ b/sig/nostr/key_pair.rbs
@@ -1,9 +1,13 @@
 # Classes
 module Nostr
  class KeyPair
-    attr_reader private_key: String
-    attr_reader public_key: String
+    attr_reader private_key: PrivateKey
+    attr_reader public_key: PublicKey

-    def initialize: (private_key: String, public_key: String) -> void
+    def initialize: (private_key: PrivateKey, public_key: PublicKey) -> void
+
+    private
+
+    def validate_keys: (PrivateKey, PublicKey) -> void
  end
 end
--- a/sig/nostr/keygen.rbs
+++ b/sig/nostr/keygen.rbs
@@ -3,11 +3,14 @@ module Nostr
  class Keygen
    def initialize: -> void
    def generate_key_pair: -> KeyPair
-    def generate_private_key: -> String
-    def extract_public_key: (String private_key) -> String
+    def generate_private_key: -> PrivateKey
+    def extract_public_key: (PrivateKey private_key) -> PublicKey
+    def get_key_pair_from_private_key: (PrivateKey private_key) -> KeyPair

    private

    attr_reader group: untyped
+
+    def validate_private_key: (PrivateKey private_key) -> void
  end
 end
--- a/sig/nostr/private_key.rbs
+++ b/sig/nostr/private_key.rbs
@@ -0,0 +1,4 @@
+module Nostr
+  class PrivateKey < Key
+  end
+end
--- a/sig/nostr/public_key.rbs
+++ b/sig/nostr/public_key.rbs
@@ -0,0 +1,4 @@
+module Nostr
+  class PublicKey < Key
+  end
+end
--- a/sig/nostr/relay_message_type.rbs
+++ b/sig/nostr/relay_message_type.rbs
@@ -0,0 +1,8 @@
+module Nostr
+  module RelayMessageType
+    EOSE: String
+    EVENT: String
+    NOTICE: String
+    OK: String
+  end
+end
--- a/sig/nostr/user.rbs
+++ b/sig/nostr/user.rbs
@@ -5,14 +5,10 @@ module Nostr

    def initialize: (?keypair: KeyPair | nil, ?keygen: Keygen) -> void
    def create_event: (
-      {
-        pubkey: String,
-        created_at: Integer,
-        kind: Integer,
-        tags: Array[String],
-        content: String,
-        created_at: Integer,
-      }
+      kind: Integer,
+      content: String,
+      ?created_at: Integer,
+      ?tags: Array[Array[String]],
    ) -> Event

    private
--- a/sig/vendor/bech32.rbs
+++ b/sig/vendor/bech32.rbs
@@ -0,0 +1,25 @@
+# Added only to satisfy the Steep requirements. Not 100% reliable.
+module Bech32
+  SEPARATOR: String
+  BECH32M_CONST: Integer
+
+  def encode: (untyped hrp, untyped data, untyped spec) -> untyped
+  def self.encode: (untyped hrp, untyped data, untyped spec) -> untyped
+  def decode: (untyped bech, ?Integer max_length) -> [untyped, untyped, Integer]?
+  def self.decode: (untyped bech, ?Integer max_length) -> [untyped, untyped, Integer]?
+  def create_checksum: (untyped hrp, untyped data, untyped spec) -> Array[Integer]
+  def self.create_checksum: (untyped hrp, untyped data, untyped spec) -> Array[Integer]
+  def verify_checksum: (untyped hrp, untyped data) -> Integer?
+  def self.verify_checksum: (untyped hrp, untyped data) -> Integer?
+  def expand_hrp: (untyped hrp) -> untyped
+  def self.expand_hrp: (untyped hrp) -> untyped
+  def convert_bits: (untyped data, untyped from, untyped to, ?true padding) -> Array[Integer]?
+  def self.convert_bits: (untyped data, untyped from, untyped to, ?true padding) -> Array[Integer]?
+  def polymod: (untyped values) -> Integer
+  def self.polymod: (untyped values) -> Integer
+
+  module Encoding
+    BECH32: Integer
+    BECH32M: Integer
+  end
+end
--- a/sig/vendor/bech32/nostr/entity.rbs
+++ b/sig/vendor/bech32/nostr/entity.rbs
@@ -0,0 +1,41 @@
+# Added only to satisfy the Steep requirements. Not 100% reliable.
+module Bech32
+  module Nostr
+    class BareEntity
+      attr_reader hrp: untyped
+      attr_reader data: untyped
+
+      def initialize: (untyped hrp, untyped data) -> void
+      def encode: -> untyped
+    end
+
+    class TLVEntry
+      attr_reader type: (Float | Integer | String)?
+      attr_reader label: String?
+      attr_reader value: (Float | Integer | String)?
+
+      def initialize: ((Float | Integer | String)? `type`, (Float | Integer | String)? value, ?String? label) -> void
+      def to_payload: -> String
+      def to_s: -> String
+
+      private
+
+      def hex_string?: ((Float | Integer | String)? str) -> bool
+    end
+
+    class TLVEntity
+      TYPE_SPECIAL: Integer
+      TYPE_RELAY: Integer
+      TYPE_AUTHOR: Integer
+      TYPE_KIND: Integer
+      TYPES: [Integer, Integer, Integer, Integer]
+
+      attr_reader hrp: untyped
+      attr_reader entries: Array[TLVEntry]
+
+      def initialize: (untyped hrp, Array[TLVEntry] entries) -> void
+      def self.parse: (untyped hrp, untyped data) -> TLVEntity
+      def encode: -> untyped
+    end
+  end
+end
--- a/sig/vendor/bech32/nostr/nip19.rbs
+++ b/sig/vendor/bech32/nostr/nip19.rbs
@@ -0,0 +1,20 @@
+# Added only to satisfy the Steep requirements. Not 100% reliable.
+module Bech32
+  module Nostr
+    module NIP19
+      HRP_PUBKEY: String
+      HRP_PRIVATE_KEY: String
+      HRP_NOTE_ID: String
+      HRP_PROFILE: String
+      HRP_EVENT: String
+      HRP_RELAY: String
+      HRP_EVENT_COORDINATE: String
+      BARE_PREFIXES: [String, String, String]
+      TLV_PREFIXES: [String, String, String, String]
+      ALL_PREFIXES: Array[String]
+
+      def decode: (untyped string) -> untyped
+      def self.decode: (untyped string) -> untyped
+    end
+  end
+end
--- a/sig/vendor/bech32/segwit_addr.rbs
+++ b/sig/vendor/bech32/segwit_addr.rbs
@@ -0,0 +1,21 @@
+# Added only to satisfy the Steep requirements. Not 100% reliable.
+module Bech32
+  class SegwitAddr
+    HRP_MAINNET: String
+    HRP_TESTNET: String
+    HRP_REGTEST: String
+
+    attr_accessor hrp: String
+    attr_accessor ver: (Float | Integer | String)?
+    attr_accessor prog: Array[(Float | Integer | String)?]
+
+    def initialize: (?nil addr) -> void
+    def to_script_pubkey: -> ((Float | Integer | String)?)
+    def script_pubkey=: (untyped script_pubkey) -> (Array[(Float | Integer | String)?])
+    def addr: -> untyped
+
+    private
+
+    def parse_addr: (untyped addr) -> nil
+  end
+end
--- a/sig/vendor/event_emitter.rbs
+++ b/sig/vendor/event_emitter.rbs
@@ -1,9 +1,16 @@
 # Added only to satisfy the Steep requirements. Not 100% reliable.
 module EventEmitter
-  def add_listener: (untyped `type`, ?{once: true} params) -> Integer
+  interface _Event
+    def data: -> String
+    def message: -> String
+    def code: -> Integer
+    def reason: -> String
+  end
+
+  def add_listener: (Symbol event_name) { (_Event event) -> void } -> void
  alias on add_listener

  def remove_listener: (untyped id_or_type) -> Array[untyped]?
-  def emit: (untyped `type`, *untyped data) -> Array[untyped]
-  def once: (untyped `type`) -> Integer
+  def emit: (Symbol `type`, *untyped data) -> Array[untyped]
+  def once: (Symbol `type`) -> Integer
 end
--- a/sig/vendor/event_machine/channel.rbs
+++ b/sig/vendor/event_machine/channel.rbs
@@ -6,7 +6,7 @@ module EventMachine

    def initialize: -> void
    def num_subscribers: -> Integer
-    def subscribe: (*untyped a) ?{ -> untyped } -> Integer
+    def subscribe: (*untyped a) ?{ (untyped) -> untyped } -> Integer
    def unsubscribe: (untyped name) -> untyped
    def push: (*untyped items) -> untyped
    alias << push
--- a/sig/vendor/faye/websocket.rbs
+++ b/sig/vendor/faye/websocket.rbs
@@ -0,0 +1,30 @@
+# Added only to satisfy the Steep requirements. Not 100% reliable.
+module Faye
+  class WebSocket
+    ADAPTERS: Hash[String, :Goliath | :Rainbows | :Thin]
+
+    @url: String
+    @driver_started: false
+    @stream: Stream
+    @driver: bot
+
+    def self.determine_url: (untyped env, ?[String, String] schemes) -> String
+    def self.ensure_reactor_running: -> nil
+    def self.load_adapter: (untyped backend) -> bool?
+    def self.secure_request?: (untyped env) -> bool
+    def self.websocket?: (untyped env) -> untyped
+
+    attr_reader env: untyped
+
+    def initialize: (untyped env, ?nil protocols, ?Hash[untyped, untyped] options) -> void
+    def start_driver: -> nil
+    def rack_response: -> [Integer, Hash[untyped, untyped], Array[untyped]]
+
+    class Stream
+      @socket_object: bot
+
+      def fail: -> untyped
+      def receive: (untyped data) -> untyped
+    end
+  end
+end
--- a/sig/vendor/faye/websocket/api.rbs
+++ b/sig/vendor/faye/websocket/api.rbs
@@ -0,0 +1,45 @@
+# Added only to satisfy the Steep requirements. Not 100% reliable.
+module Faye
+  class WebSocket
+    module API
+      CONNECTING: Integer
+      OPEN: Integer
+      CLOSING: Integer
+      CLOSED: Integer
+      CLOSE_TIMEOUT: Integer
+
+      @driver: untyped
+      @ping: nil
+      @ping_id: Integer
+      @stream: nil
+      @proxy: nil
+      @ping_timer: nil
+      @close_timer: nil
+      @close_params: [String, Integer]?
+      @onerror: nil
+      @onclose: nil
+      @onmessage: nil
+      @onopen: nil
+
+      attr_reader url: untyped
+      attr_reader ready_state: Integer
+      attr_reader buffered_amount: Integer
+
+      def initialize: (?Hash[untyped, untyped] options) -> void
+      def write: (untyped data) -> untyped
+      def send: (untyped message) -> false
+      def ping: (?String message) -> false
+      def close: (?nil code, ?nil reason) -> untyped
+      def protocol: -> String
+
+      private
+
+      def open: -> nil
+      def receive_message: (untyped data) -> nil
+      def emit_error: (untyped message) -> nil
+      def begin_close: (String reason, Integer code, ?Hash[untyped, untyped] options) -> nil
+      def finalize_close: -> nil
+      def parse: (untyped data) -> untyped
+    end
+  end
+end
--- a/sig/vendor/faye/websocket/client.rbs
+++ b/sig/vendor/faye/websocket/client.rbs
@@ -0,0 +1,43 @@
+# Added only to satisfy the Steep requirements. Not 100% reliable.
+module Faye
+  class WebSocket
+    class Client
+      DEFAULT_PORTS: Hash[String, Integer]
+      SECURE_PROTOCOLS: [String, String]
+
+      include EventEmitter
+      include API
+
+      @url: untyped
+      @endpoint: untyped
+      @origin_tls: Hash[untyped, untyped]
+      @socket_tls: Hash[untyped, untyped]
+      @driver: bot
+      @proxy: nil
+      @ssl_verifier: untyped
+      @stream: untyped
+
+      def initialize: (untyped url, ?Array[String] protocols, ?Hash[untyped, untyped] options) -> void
+
+      private
+
+      def configure_proxy: (Hash[untyped, untyped] proxy) -> nil
+      def start_tls: (untyped uri, Hash[untyped, untyped] options) -> nil
+      def on_connect: (untyped stream) -> untyped
+      def on_network_error: (nil error) -> untyped
+      def ssl_verify_peer: (untyped cert) -> untyped
+      def ssl_handshake_completed: -> untyped
+
+      module Connection
+        attr_accessor parent: bot
+
+        def connection_completed: -> untyped
+        def ssl_verify_peer: (untyped cert) -> untyped
+        def ssl_handshake_completed: -> untyped
+        def receive_data: (untyped data) -> untyped
+        def unbind: (?nil error) -> untyped
+        def write: (untyped data) -> nil
+      end
+    end
+  end
+end
--- a/spec/nostr/bech32_spec.rb
+++ b/spec/nostr/bech32_spec.rb
@@ -0,0 +1,139 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Nostr::Bech32 do
+  let(:keypair) { Nostr::Keygen.new.generate_key_pair }
+  let(:private_key) { keypair.private_key }
+  let(:public_key) { keypair.public_key }
+
+  describe '.encode' do
+    it 'encodes data into the bech32 format' do
+      npub = described_class.encode(hrp: 'npub', data: public_key)
+      expect(npub).to match(/npub1\w+/)
+    end
+  end
+
+  describe '.decode' do
+    it 'decodes data from the bech32 format' do
+      npub = described_class.encode(hrp: 'npub', data: public_key)
+      type, decoded = described_class.decode(npub)
+
+      aggregate_failures do
+        expect(type).to eq('npub')
+        expect(decoded).to eq(public_key)
+      end
+    end
+  end
+
+  describe '.nsec_encode' do
+    it 'encodes and decodes hexadecimal private keys' do
+      nsec = described_class.nsec_encode(private_key)
+      type, data = described_class.decode(nsec)
+
+      aggregate_failures do
+        expect(nsec).to match(/nsec1\w+/)
+        expect(type).to eq('nsec')
+        expect(data).to eq(private_key)
+      end
+    end
+  end
+
+  describe '.npub_encode' do
+    it 'encodes and decodes hexadecimal public keys' do
+      npub = described_class.npub_encode(public_key)
+      type, data = described_class.decode(npub)
+
+      aggregate_failures do
+        expect(npub).to match(/npub1\w+/)
+        expect(type).to eq('npub')
+        expect(data).to eq(public_key)
+      end
+    end
+  end
+
+  describe '.nprofile_encode' do
+    it 'encodes and decodes nprofiles with relays' do
+      relay_urls = %w[wss://relay.damus.io wss://nos.lol]
+      nprofile = described_class.nprofile_encode(pubkey: public_key, relays: relay_urls)
+      type, profile = described_class.decode(nprofile)
+
+      aggregate_failures do
+        expect(nprofile).to match(/nprofile1\w+/)
+        expect(type).to eq('nprofile')
+        expect(profile.entries[0].value).to eq(public_key)
+        expect(profile.entries[1].value).to eq(relay_urls[0])
+        expect(profile.entries[2].value).to eq(relay_urls[1])
+      end
+    end
+
+    it 'encodes and decodes nprofiles without relays' do
+      nprofile = described_class.nprofile_encode(pubkey: public_key)
+      type, profile = described_class.decode(nprofile)
+
+      aggregate_failures do
+        expect(nprofile).to match(/nprofile1\w+/)
+        expect(type).to eq('nprofile')
+        expect(profile.entries[0].value).to eq(public_key)
+      end
+    end
+  end
+
+  describe '.naddr_encode' do
+    it 'encodes and decodes naddr' do
+      relay_urls = %w[wss://relay.damus.io wss://nos.lol]
+      naddr = described_class.naddr_encode(
+        pubkey: public_key,
+        relays: relay_urls,
+        kind: 1984,
+        identifier: 'damus'
+      )
+      type, addr = described_class.decode(naddr)
+
+      aggregate_failures do
+        expect(naddr).to match(/naddr1\w+/)
+        expect(type).to eq('naddr')
+        expect(addr.entries[0].value).to eq(public_key)
+        expect(addr.entries[1].value).to eq(relay_urls[0])
+        expect(addr.entries[2].value).to eq(relay_urls[1])
+        expect(addr.entries[3].value).to eq(1984)
+        expect(addr.entries[4].value).to eq('damus')
+      end
+    end
+  end
+
+  describe '.nevent_encode' do
+    it 'encodes and decodes nevent' do
+      relay_urls = %w[wss://relay.damus.io wss://nos.lol]
+      nevent = described_class.nevent_encode(
+        id: '0fdb90f8e234d3400edafdd26d493f12efc0d7de2c6f9f21f997847d33ad2ea3',
+        relays: relay_urls,
+        kind: Nostr::EventKind::TEXT_NOTE
+      )
+      type, event = described_class.decode(nevent)
+
+      aggregate_failures do
+        expect(nevent).to match(/nevent1\w+/)
+        expect(type).to eq('nevent')
+        expect(event.entries[0].value).to eq('0fdb90f8e234d3400edafdd26d493f12efc0d7de2c6f9f21f997847d33ad2ea3')
+        expect(event.entries[1].value).to eq(relay_urls[0])
+        expect(event.entries[2].value).to eq(relay_urls[1])
+        expect(event.entries[3].value).to eq(Nostr::EventKind::TEXT_NOTE)
+      end
+    end
+  end
+
+  describe '.nrelay_encode' do
+    it 'encodes and decodes nrelay' do
+      relay_url = 'wss://relay.damus.io'
+      nrelay = described_class.nrelay_encode(relay_url)
+      type, data = described_class.decode(nrelay)
+
+      aggregate_failures do
+        expect(nrelay).to match(/nrelay1\w+/)
+        expect(type).to eq('nrelay')
+        expect(data.entries[0].value).to eq(relay_url)
+      end
+    end
+  end
+end
--- a/spec/nostr/crypto_spec.rb
+++ b/spec/nostr/crypto_spec.rb
@@ -8,8 +8,8 @@ RSpec.describe Nostr::Crypto do
  describe '#sign_event' do
    let(:keypair) do
      Nostr::KeyPair.new(
-        public_key: '8a9d69c56e3c691bec8f9565e4dcbe38ae1d88fffeec3ce66b9f47558a3aa8ca',
-        private_key: '3185a47e3802f956ca5a2b4ea606c1d51c7610f239617e8f0f218d55bdf2b757'
+        public_key: Nostr::PublicKey.new('8a9d69c56e3c691bec8f9565e4dcbe38ae1d88fffeec3ce66b9f47558a3aa8ca'),
+        private_key: Nostr::PrivateKey.new('3185a47e3802f956ca5a2b4ea606c1d51c7610f239617e8f0f218d55bdf2b757')
      )
    end

@@ -34,15 +34,15 @@ RSpec.describe Nostr::Crypto do
  describe '#encrypt_text' do
    let(:sender_keypair) do
      Nostr::KeyPair.new(
-        public_key: '8a9d69c56e3c691bec8f9565e4dcbe38ae1d88fffeec3ce66b9f47558a3aa8ca',
-        private_key: '3185a47e3802f956ca5a2b4ea606c1d51c7610f239617e8f0f218d55bdf2b757'
+        public_key: Nostr::PublicKey.new('8a9d69c56e3c691bec8f9565e4dcbe38ae1d88fffeec3ce66b9f47558a3aa8ca'),
+        private_key: Nostr::PrivateKey.new('3185a47e3802f956ca5a2b4ea606c1d51c7610f239617e8f0f218d55bdf2b757')
      )
    end

    let(:recipient_keypair) do
      Nostr::KeyPair.new(
-        public_key: '6c31422248998e300a1a457167565da7d15d0da96651296ee2791c29c11b6aa0',
-        private_key: '22cea01c33eccf30fdd54cb6728f814f6de00c778aafd721e017f4582545f9cf'
+        public_key: Nostr::PublicKey.new('6c31422248998e300a1a457167565da7d15d0da96651296ee2791c29c11b6aa0'),
+        private_key: Nostr::PrivateKey.new('22cea01c33eccf30fdd54cb6728f814f6de00c778aafd721e017f4582545f9cf')
      )
    end

@@ -57,23 +57,34 @@ RSpec.describe Nostr::Crypto do
  describe '#descrypt_text' do
    let(:sender_keypair) do
      Nostr::KeyPair.new(
-        public_key: '8a9d69c56e3c691bec8f9565e4dcbe38ae1d88fffeec3ce66b9f47558a3aa8ca',
-        private_key: '3185a47e3802f956ca5a2b4ea606c1d51c7610f239617e8f0f218d55bdf2b757'
+        public_key: Nostr::PublicKey.new('8a9d69c56e3c691bec8f9565e4dcbe38ae1d88fffeec3ce66b9f47558a3aa8ca'),
+        private_key: Nostr::PrivateKey.new('3185a47e3802f956ca5a2b4ea606c1d51c7610f239617e8f0f218d55bdf2b757')
      )
    end

    let(:recipient_keypair) do
      Nostr::KeyPair.new(
-        public_key: '6c31422248998e300a1a457167565da7d15d0da96651296ee2791c29c11b6aa0',
-        private_key: '22cea01c33eccf30fdd54cb6728f814f6de00c778aafd721e017f4582545f9cf'
+        public_key: Nostr::PublicKey.new('6c31422248998e300a1a457167565da7d15d0da96651296ee2791c29c11b6aa0'),
+        private_key: Nostr::PrivateKey.new('22cea01c33eccf30fdd54cb6728f814f6de00c778aafd721e017f4582545f9cf')
      )
    end

-    it 'decrypts an encrypted text' do
-      encrypted_text = crypto.encrypt_text(sender_keypair.private_key, recipient_keypair.public_key, 'Twitter Files')
-      decrypted_text = crypto.decrypt_text(recipient_keypair.private_key, sender_keypair.public_key, encrypted_text)
+    context 'when the encrypted text includes an iv query string' do
+      it 'decrypts an encrypted text' do
+        encrypted_text = crypto.encrypt_text(sender_keypair.private_key, recipient_keypair.public_key, 'Twitter Files')
+        decrypted_text = crypto.decrypt_text(recipient_keypair.private_key, sender_keypair.public_key, encrypted_text)

-      expect(decrypted_text).to eq('Twitter Files')
+        expect(decrypted_text).to eq('Twitter Files')
+      end
+    end
+
+    context 'when the encrypted text does not include an iv query string' do
+      it 'returns an empty string' do
+        encrypted_text = 'wrYQaHDfpOEvyJELSCg1vzsywmlJTz8NqH03eFW44s8iQs869jtSb26Lr4s23gmY?it=v38vAJ3LlJAGZxbmWU4qAg=='
+        decrypted_text = crypto.decrypt_text(recipient_keypair.private_key, sender_keypair.public_key, encrypted_text)
+
+        expect(decrypted_text).to eq('')
+      end
    end
  end
 end
--- a/spec/nostr/errors/invalid_hrp_error_spec.rb
+++ b/spec/nostr/errors/invalid_hrp_error_spec.rb
@@ -0,0 +1,15 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Nostr::InvalidHRPError do
+  describe '#initialize' do
+    let(:given_hrp) { 'nwrong' }
+    let(:allowed_hrp) { 'nsec' }
+    let(:error) { described_class.new(given_hrp, allowed_hrp) }
+
+    it 'builds a useful error message' do
+      expect(error.message).to eq("Invalid hrp: nwrong. The allowed hrp value for this kind of entity is 'nsec'.")
+    end
+  end
+end
--- a/spec/nostr/errors/invalid_key_format_error_spec.rb
+++ b/spec/nostr/errors/invalid_key_format_error_spec.rb
@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Nostr::InvalidKeyFormatError do
+  describe '#initialize' do
+    let(:key_kind) { 'private' }
+    let(:error) { described_class.new(key_kind) }
+
+    it 'builds a useful error message' do
+      expect(error.message).to eq('Only lowercase hexadecimal characters are allowed in private keys.')
+    end
+  end
+end
--- a/spec/nostr/errors/invalid_key_length_error_spec.rb
+++ b/spec/nostr/errors/invalid_key_length_error_spec.rb
@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Nostr::InvalidKeyLengthError do
+  describe '#initialize' do
+    let(:key_kind) { 'private' }
+    let(:error) { described_class.new(key_kind) }
+
+    it 'builds a useful error message' do
+      expect(error.message).to eq('Invalid private key length. It should have 64 characters.')
+    end
+  end
+end
--- a/spec/nostr/errors/invalid_key_type_error_spec.rb
+++ b/spec/nostr/errors/invalid_key_type_error_spec.rb
@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Nostr::InvalidKeyTypeError do
+  describe '#initialize' do
+    let(:key_kind) { 'private' }
+    let(:error) { described_class.new(key_kind) }
+
+    it 'builds a useful error message' do
+      expect(error.message).to eq('Invalid private key type')
+    end
+  end
+end
--- a/spec/nostr/event_spec.rb
+++ b/spec/nostr/event_spec.rb
@@ -233,8 +233,8 @@ RSpec.describe Nostr::Event do
    end
    let(:keypair) do
      Nostr::KeyPair.new(
-        public_key: '8a9d69c56e3c691bec8f9565e4dcbe38ae1d88fffeec3ce66b9f47558a3aa8ca',
-        private_key: '3185a47e3802f956ca5a2b4ea606c1d51c7610f239617e8f0f218d55bdf2b757'
+        public_key: Nostr::PublicKey.new('8a9d69c56e3c691bec8f9565e4dcbe38ae1d88fffeec3ce66b9f47558a3aa8ca'),
+        private_key: Nostr::PrivateKey.new('3185a47e3802f956ca5a2b4ea606c1d51c7610f239617e8f0f218d55bdf2b757')
      )
    end

--- a/spec/nostr/events/encrypted_direct_message_spec.rb
+++ b/spec/nostr/events/encrypted_direct_message_spec.rb
@@ -6,15 +6,15 @@ RSpec.describe Nostr::Events::EncryptedDirectMessage do
  describe '.new' do
    let(:sender_keypair) do
      Nostr::KeyPair.new(
-        public_key: '8a9d69c56e3c691bec8f9565e4dcbe38ae1d88fffeec3ce66b9f47558a3aa8ca',
-        private_key: '3185a47e3802f956ca5a2b4ea606c1d51c7610f239617e8f0f218d55bdf2b757'
+        public_key: Nostr::PublicKey.new('8a9d69c56e3c691bec8f9565e4dcbe38ae1d88fffeec3ce66b9f47558a3aa8ca'),
+        private_key: Nostr::PrivateKey.new('3185a47e3802f956ca5a2b4ea606c1d51c7610f239617e8f0f218d55bdf2b757')
      )
    end

    let(:recipient_keypair) do
      Nostr::KeyPair.new(
-        public_key: '6c31422248998e300a1a457167565da7d15d0da96651296ee2791c29c11b6aa0',
-        private_key: '22cea01c33eccf30fdd54cb6728f814f6de00c778aafd721e017f4582545f9cf'
+        public_key: Nostr::PublicKey.new('6c31422248998e300a1a457167565da7d15d0da96651296ee2791c29c11b6aa0'),
+        private_key: Nostr::PrivateKey.new('22cea01c33eccf30fdd54cb6728f814f6de00c778aafd721e017f4582545f9cf')
      )
    end

--- a/spec/nostr/key_pair_spec.rb
+++ b/spec/nostr/key_pair_spec.rb
@@ -5,19 +5,43 @@ require 'spec_helper'
 RSpec.describe Nostr::KeyPair do
  let(:keypair) do
    described_class.new(
-      private_key: '893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900',
-      public_key: '2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558'
+      private_key: Nostr::PrivateKey.new('893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900'),
+      public_key: Nostr::PublicKey.new('2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558')
    )
  end

  describe '.new' do
-    it 'creates an instance of a key pair' do
-      keypair = described_class.new(
-        private_key: '893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900',
-        public_key: '2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558'
-      )
+    context 'when private_key is not an instance of PrivateKey' do
+      it 'raises an error' do
+        expect do
+          described_class.new(
+            private_key: '893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900',
+            public_key: Nostr::PublicKey.new('2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558')
+          )
+        end.to raise_error(ArgumentError, 'private_key is not an instance of PrivateKey')
+      end
+    end

-      expect(keypair).to be_an_instance_of(described_class)
+    context 'when public_key is not an instance of PublicKey' do
+      it 'raises an error' do
+        expect do
+          described_class.new(
+            private_key: Nostr::PrivateKey.new('893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900'),
+            public_key: '2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558'
+          )
+        end.to raise_error(ArgumentError, 'public_key is not an instance of PublicKey')
+      end
+    end
+
+    context 'when private_key is an instance of PrivateKey and public_key is an instance of PublicKey' do
+      it 'creates an instance of a key pair' do
+        keypair = described_class.new(
+          private_key: Nostr::PrivateKey.new('893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900'),
+          public_key: Nostr::PublicKey.new('2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558')
+        )
+
+        expect(keypair).to be_an_instance_of(described_class)
+      end
    end
  end

--- a/spec/nostr/key_spec.rb
+++ b/spec/nostr/key_spec.rb
@@ -0,0 +1,73 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Nostr::Key do
+  let(:subclass) do
+    Class.new(Nostr::Key) do
+      def self.hrp
+        'npub'
+      end
+
+      protected
+
+      def validate_hex_value(_hex_value) = nil
+    end
+  end
+
+  let(:valid_hex) { 'a' * 64 }
+
+  describe '.new' do
+    it 'raises an error because this is an abstract class' do
+      expect { described_class.new(valid_hex) }.to raise_error(/Subclasses must implement this method/)
+    end
+  end
+
+  describe '.from_bech32' do
+    context 'when given a valid Bech32 value' do
+      let(:valid_bech32) { 'npub10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qzvjptg' }
+
+      it 'creates a new key' do
+        expect { subclass.from_bech32(valid_bech32) }.not_to raise_error
+      end
+    end
+
+    context 'when given an invalid Bech32 value' do
+      let(:invalid_bech32) { 'this is obviously not valid' }
+
+      it 'raises an error' do
+        expect { subclass.from_bech32(invalid_bech32) }.to raise_error(ArgumentError, /Invalid nip19 string\./)
+      end
+    end
+  end
+
+  describe '.hrp' do
+    context 'when called on the abstract class' do
+      it 'raises an error because this is an abstract method' do
+        expect { described_class.hrp }.to raise_error(/Subclasses must implement this method/)
+      end
+    end
+
+    context 'when called on a subclass' do
+      it 'returns the human readable part of a Bech32 string' do
+        expect(subclass.hrp).to eq('npub')
+      end
+    end
+  end
+
+  describe '#to_bech32' do
+    let(:key) { subclass.new(valid_hex) }
+
+    it 'returns a bech32 string representation of the key' do
+      expect(key.to_bech32).to match(/^npub[0-9a-z]+$/)
+    end
+  end
+
+  describe '#validate_hex_value' do
+    let(:invalid_hex) { 'g' * 64 }
+
+    it 'raises an error because this is an abstract method' do
+      expect { described_class.new(invalid_hex) }.to raise_error(/Subclasses must implement this method/)
+    end
+  end
+end
--- a/spec/nostr/keygen_spec.rb
+++ b/spec/nostr/keygen_spec.rb
@@ -13,6 +13,31 @@ RSpec.describe Nostr::Keygen do
    end
  end

+  describe '.get_key_pair_from_private_key' do
+    context 'when given a private key' do
+      let(:private_key) { Nostr::PrivateKey.new('893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900') }
+
+      it 'generates a key pair' do
+        keypair = keygen.get_key_pair_from_private_key(private_key)
+
+        aggregate_failures do
+          expect(keypair.private_key).to be_an_instance_of(Nostr::PrivateKey)
+          expect(keypair.public_key).to be_an_instance_of(Nostr::PublicKey)
+        end
+      end
+    end
+
+    context 'when given another kind of value' do
+      let(:not_a_private_key) { 'something else' }
+
+      it 'raises an error' do
+        expect { keygen.get_key_pair_from_private_key(not_a_private_key) }.to raise_error(
+          ArgumentError, 'private_key is not an instance of PrivateKey'
+        )
+      end
+    end
+  end
+
  describe '#generate_key_pair' do
    it 'generates a private/public key pair' do
      keypair = keygen.generate_key_pair
@@ -33,11 +58,24 @@ RSpec.describe Nostr::Keygen do
  end

  describe '#extract_public_key' do
-    it 'extracts a public key from a private key' do
-      private_key = '893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900'
-      public_key = keygen.extract_public_key(private_key)
+    context 'when the given value is not a private key' do
+      let(:not_a_private_key) { 'something else' }

-      expect(public_key).to eq('2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558')
+      it 'raises an error' do
+        expect { keygen.extract_public_key(not_a_private_key) }.to raise_error(
+          ArgumentError, 'private_key is not an instance of PrivateKey'
+        )
+      end
+    end
+
+    context 'when the given value is a private key' do
+      let(:private_key) { Nostr::PrivateKey.new('893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900') }
+
+      it 'extracts a public key from a private key' do
+        public_key = keygen.extract_public_key(private_key)
+
+        expect(public_key).to eq('2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558')
+      end
    end
  end
 end
--- a/spec/nostr/private_key_spec.rb
+++ b/spec/nostr/private_key_spec.rb
@@ -0,0 +1,82 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Nostr::PrivateKey do
+  let(:valid_hex) { '67dea2ed018072d675f5415ecfaed7d2597555e202d85b3d65ea4e58d2d92ffa' }
+  let(:private_key) { described_class.new(valid_hex) }
+
+  describe '.new' do
+    context 'when the private key is not a string' do
+      it 'raises an InvalidKeyTypeError' do
+        expect { described_class.new(1234) }.to raise_error(
+          Nostr::InvalidKeyTypeError,
+          'Invalid private key type'
+        )
+      end
+    end
+
+    context "when the private key's length is not 64 characters" do
+      it 'raises an InvalidKeyLengthError' do
+        expect { described_class.new('a' * 65) }.to raise_error(
+          Nostr::InvalidKeyLengthError,
+          'Invalid private key length. It should have 64 characters.'
+        )
+      end
+    end
+
+    context 'when the private key contains non-hexadecimal characters' do
+      it 'raises an InvalidKeyFormatError' do
+        expect { described_class.new('g' * 64) }.to raise_error(
+          Nostr::InvalidKeyFormatError,
+          'Only lowercase hexadecimal characters are allowed in private keys.'
+        )
+      end
+    end
+
+    context 'when the private key contains uppercase characters' do
+      it 'raises an InvalidKeyFormatError' do
+        expect { described_class.new('A' * 64) }.to raise_error(
+          Nostr::InvalidKeyFormatError,
+          'Only lowercase hexadecimal characters are allowed in private keys.'
+        )
+      end
+    end
+
+    context 'when the private key is valid' do
+      it 'does not raise any error' do
+        expect { described_class.new('a' * 64) }.not_to raise_error
+      end
+    end
+  end
+
+  describe '.from_bech32' do
+    context 'when given a valid Bech32 value' do
+      let(:valid_bech32) { 'nsec1vl029mgpspedva04g90vltkh6fvh240zqtv9k0t9af8935ke9laqsnlfe5' }
+
+      it 'instantiates a private key from a Bech32 encoded string' do
+        expect(described_class.from_bech32(valid_bech32)).to eq(valid_hex)
+      end
+    end
+
+    context 'when given an invalid Bech32 value' do
+      let(:invalid_bech32) { 'this is obviously not valid' }
+
+      it 'raises an error' do
+        expect { described_class.from_bech32(invalid_bech32) }.to raise_error(ArgumentError, /Invalid nip19 string\./)
+      end
+    end
+  end
+
+  describe '.hrp' do
+    it 'returns the human readable part of a Bech32 string' do
+      expect(described_class.hrp).to eq('nsec')
+    end
+  end
+
+  describe '#to_bech32' do
+    it 'converts the hex key to bech32' do
+      expect(private_key.to_bech32).to eq('nsec1vl029mgpspedva04g90vltkh6fvh240zqtv9k0t9af8935ke9laqsnlfe5')
+    end
+  end
+end
--- a/spec/nostr/public_key_spec.rb
+++ b/spec/nostr/public_key_spec.rb
@@ -0,0 +1,82 @@
+# frozen_string_literal: true
+
+require 'spec_helper'
+
+RSpec.describe Nostr::PublicKey do
+  let(:valid_hex) { '7e7e9c42a91bfef19fa929e5fda1b72e0ebc1a4c1141673e2794234d86addf4e' }
+  let(:public_key) { described_class.new(valid_hex) }
+
+  describe '.new' do
+    context 'when the public key is not a string' do
+      it 'raises an InvalidKeyTypeError' do
+        expect { described_class.new(1234) }.to raise_error(
+          Nostr::InvalidKeyTypeError,
+          'Invalid public key type'
+        )
+      end
+    end
+
+    context "when the public key's length is not 64 characters" do
+      it 'raises an InvalidKeyLengthError' do
+        expect { described_class.new('a' * 65) }.to raise_error(
+          Nostr::InvalidKeyLengthError,
+          'Invalid public key length. It should have 64 characters.'
+        )
+      end
+    end
+
+    context 'when the public key contains non-hexadecimal characters' do
+      it 'raises an InvalidKeyFormatError' do
+        expect { described_class.new('g' * 64) }.to raise_error(
+          Nostr::InvalidKeyFormatError,
+          'Only lowercase hexadecimal characters are allowed in public keys.'
+        )
+      end
+    end
+
+    context 'when the public key contains uppercase characters' do
+      it 'raises an InvalidKeyFormatError' do
+        expect { described_class.new('A' * 64) }.to raise_error(
+          Nostr::InvalidKeyFormatError,
+          'Only lowercase hexadecimal characters are allowed in public keys.'
+        )
+      end
+    end
+
+    context 'when the public key is valid' do
+      it 'does not raise any error' do
+        expect { described_class.new('a' * 64) }.not_to raise_error
+      end
+    end
+  end
+
+  describe '.from_bech32' do
+    context 'when given a valid Bech32 value' do
+      let(:valid_bech32) { 'npub10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qzvjptg' }
+
+      it 'instantiates a public key from a Bech32 encoded string' do
+        expect(described_class.from_bech32(valid_bech32)).to eq(valid_hex)
+      end
+    end
+
+    context 'when given an invalid Bech32 value' do
+      let(:invalid_bech32) { 'this is obviously not valid' }
+
+      it 'raises an error' do
+        expect { described_class.from_bech32(invalid_bech32) }.to raise_error(ArgumentError, /Invalid nip19 string\./)
+      end
+    end
+  end
+
+  describe '.hrp' do
+    it 'returns the human readable part of a Bech32 string' do
+      expect(described_class.hrp).to eq('npub')
+    end
+  end
+
+  describe '#to_bech32' do
+    it 'converts the hex key to bech32' do
+      expect(public_key.to_bech32).to eq('npub10elfcs4fr0l0r8af98jlmgdh9c8tcxjvz9qkw038js35mp4dma8qzvjptg')
+    end
+  end
+end
--- a/spec/nostr/user_spec.rb
+++ b/spec/nostr/user_spec.rb
@@ -5,8 +5,8 @@ require 'spec_helper'
 RSpec.describe Nostr::User do
  let(:keypair) do
    Nostr::KeyPair.new(
-      private_key: '893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900',
-      public_key: '2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558'
+      private_key: Nostr::PrivateKey.new('893c4cc8088924796b41dc788f7e2f746734497010b1a9f005c1faad7074b900'),
+      public_key: Nostr::PublicKey.new('2d7661527d573cc8e84f665fa971dd969ba51e2526df00c149ff8e40a58f9558')
    )
  end

--- a/Show More
+++ b/Show More
Author	SHA1	Message	Date
Wilson Silva	8bc6b84f6f	Bump the gem version to v0.5.0	2023-11-20 21:05:36 +07:00
Wilson Silva	61a88981e6	Add full NIP-19 compatibility note, nprofile, nevent, naddr, npub, nsec and nrelay	2023-11-20 21:03:24 +07:00
Wilson Silva	bba18d1bc0	Fix the generation of private keys `00c2660584`	2023-11-20 12:39:58 +07:00
Wilson Silva	b45370e65f	Remove a broken documentation link	2023-11-20 10:42:32 +07:00
Wilson Silva	53069a3d0c	Update bip-schnorr, puma, rake, rubocop and rubocop-rspec	2023-11-20 10:32:27 +07:00
Wilson Silva	3520cf8219	Implement NIP-19 bech32-encoded private and public keys https://github.com/nostr-protocol/nips/blob/master/19.md	2023-11-20 09:59:27 +07:00
Wilson Silva	3fffcd1a4e	Use keyword arguments for User#create_event This allows for code completion and fixes another RBS issue	2023-11-18 18:06:53 +07:00
Wilson Silva	2c44ae4ee8	Fix the RBS types of Nostr::Filter e, p and to_f	2023-11-18 17:22:20 +07:00
Wilson Silva	4b630c678b	Ensure that Nostr::Crypto#descrypt_text always returns a string Fixes another Steep/RBS violation	2023-11-18 16:38:03 +07:00
Wilson Silva	3077aa67a7	Fix the RBS type of Nostr::Crypto::BN_BASE	2023-11-18 16:28:31 +07:00
Wilson Silva	2584967654	Update rbs to v3.3 and steep to v1.6	2023-11-18 15:42:09 +07:00
Wilson Silva	b54147cfce	Remove unnecessary blank space	2023-11-14 16:58:14 +07:00
Wilson Silva	0f9c0d3a3d	Add relay message type enums	2023-11-14 16:57:33 +07:00
Wilson Silva	904fe46a9d	Name the implemented NIPs	2023-11-14 16:53:38 +07:00
Wilson Silva	80c272f149	Fix the formatting of encrypted direct message	2023-11-14 16:28:16 +07:00
Wilson Silva	be4c3e0e32	Update the documentation of the subscription id Match the changes introduced in https://github.com/nostr-protocol/nips/pull/299	2023-11-14 16:12:33 +07:00
Wilson Silva	30eafa1203	Remove id/pubkey prefix documentation Removed from the protocol in https://github.com/nostr-protocol/nips/pull/703	2023-11-14 16:12:32 +07:00
Wilson Silva	4f13b22e51	Update Ruby to version 3.2.2	2023-11-14 07:54:56 +07:00
Wilson Silva	6d9758a37a	Fix the subscription documentation	2023-11-14 07:45:39 +07:00
Wilson Silva	4d8803d769	Update bec32	2023-11-13 21:32:11 +07:00
Wilson Silva	e9deab2fc2	Link the changelog with the homepage	2023-11-13 18:09:51 +07:00
Wilson Silva	35c7e6a76e	Ignore my local copy of the nostr nips folder	2023-11-13 18:09:03 +07:00
Wilson Silva	8e1e3092c3	Update the changelog format version	2023-11-13 18:01:17 +07:00
Wilson Silva	eaa97e0018	Update the changelog	2023-11-13 17:58:04 +07:00
Wilson Silva	1fb7e454ae	Update the gem's homepage	2023-11-13 17:55:36 +07:00
Wilson Silva	82aacb70e7	Use my own domain instead of Vercel's	2023-11-13 17:55:25 +07:00
Wilson Silva	d49fac49b6	Add high-level documentation https://nostr-ruby.com	2023-11-13 17:48:17 +07:00
Wilson Silva	b206f6504e	Update vitepress and install mermaid diagram plugin	2023-11-13 17:43:42 +07:00
Wilson Silva	6d81d07f8a	Use bun	2023-11-13 17:43:41 +07:00
Wilson Silva	3fbc523b18	Document how to develop the documentation	2023-11-13 17:43:41 +07:00
Wilson Silva	c27de6d506	Update Puma to version 6.3 Fixes the error "Puma 5 is not compatible with Rack 3, please upgrade to Puma 6 or higher."	2023-09-16 16:13:42 +07:00
Wilson Silva	1865858230	Add the VitePress documentation scaffold	2023-09-16 15:32:53 +07:00