require 'nostr'

class User < ApplicationRecord
  include EmailValidatable

  attr_accessor :current_password
  attr_accessor :display_name
  attr_accessor :avatar_new
  attr_accessor :pgp_pubkey

  serialize :preferences, coder: UserPreferences

  #
  # Relations
  #

  has_many :invitations, dependent: :destroy
  has_one  :invitation, inverse_of: :invitee, foreign_key: 'invited_user_id'
  has_one  :inviter, through: :invitation, source: :user
  has_many :invitees, through: :invitations
  has_many :donations, dependent: :nullify
  has_many :remote_storage_authorizations
  has_many :zaps

  has_one  :lndhub_user, class_name: "LndhubUser", inverse_of: "user",
                         primary_key: "lndhub_username", foreign_key: "login"

  has_many :accounts, through: :lndhub_user

  #
  # Attachments
  #

  has_one_attached :avatar

  #
  # Validations
  #

  validates_uniqueness_of :cn, scope: :ou
  validates_length_of :cn, minimum: 3
  validates_format_of :cn, with: /\A([a-z0-9\-])*\z/,
                           if: Proc.new{ |u| u.cn.present? },
                           message: "is invalid. Please use only letters, numbers and -"
  validates_format_of :cn, without: /\A-/,
                           if: Proc.new{ |u| u.cn.present? },
                           message: "is invalid. Usernames need to start with a letter."
  # FIXME This needs a server restart to apply values
  validates_format_of :cn, without: /\A(#{Setting.reserved_usernames.join('|')})\z/i,
                           message: "has already been taken",
                           unless: Proc.new{ |u| u.persisted? }

  validates_uniqueness_of :email
  validates :email, email: true

  validates_length_of :display_name, minimum: 3, maximum: 35, allow_blank: true,
                                     if: -> { defined?(@display_name) }


  validate :acceptable_avatar

  validate :acceptable_pgp_key_format, if: -> { defined?(@pgp_pubkey) && @pgp_pubkey.present? }

  #
  # Scopes
  #

  scope :confirmed,  -> { where.not(confirmed_at: nil) }
  scope :pending,    -> { where(confirmed_at: nil) }
  scope :all_except, -> (user) { where.not(id: user) }

  #
  # Encrypted database columns
  #

  encrypts :lndhub_password

  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable, :trackable and :omniauthable
  devise :ldap_authenticatable,
         :confirmable,
         :recoverable,
         :validatable,
         :timeoutable,
         :rememberable

  #
  # Methods
  #

  def ldap_before_save
    self.email = Devise::LDAP::Adapter.get_ldap_param(self.cn, "mail").first
    self.ou    = dn.split(',')
                   .select{|e| e[0..1] == "ou"}.first
                   .delete_prefix("ou=")

    if self.confirmed_at.blank? && self.confirmation_token.blank?
      # User had an account with a trusted email address before akkounts was a thing
      self.confirmed_at = DateTime.now
    end
  end

  def devise_after_confirmation
    if ldap_entry[:mail] != self.email
      # E-Mail update confirmed
      LdapManager::UpdateEmail.call(dn: self.dn, address: self.email)
    else
      # E-Mail from signup confirmed (i.e. account activation)
      enable_default_services

      # TODO enable in development when we have easy setup of ejabberd etc.
      return if Rails.env.development? || !Setting.ejabberd_enabled?

      XmppExchangeContactsJob.perform_later(inviter, self) if inviter.present?
      XmppSetDefaultBookmarksJob.perform_later(self)
    end
  end

  def send_devise_notification(notification, *args)
    devise_mailer.send(notification, self, *args).deliver_later
  end

  def reset_password(new_password, new_password_confirmation)
    self.password = new_password
    self.password_confirmation = new_password_confirmation
    return false unless valid?

    Devise::LDAP::Adapter.update_password(login_with, new_password)
    clear_reset_password_token
    save
  end

  def is_admin?
    @admin ||= if admin = Devise::LDAP::Adapter.get_ldap_param(self.cn, :admin)
                 !!admin.first
               else
                 false
               end
  end

  def address
    "#{self.cn}@#{self.ou}"
  end

  def mastodon_address
    return nil unless Setting.mastodon_enabled?
    "#{self.cn.gsub("-", "_")}@#{Setting.mastodon_address_domain}"
  end

  def valid_attribute?(attribute_name)
    self.valid?
    self.errors[attribute_name].blank?
  end

  def enable_default_services
    enable_service Setting.default_services
  end

  def dn
    return @dn if defined?(@dn)
    @dn = Devise::LDAP::Adapter.get_dn(self.cn)
  end

  def ldap_entry(reload: false)
    return @ldap_entry if defined?(@ldap_entry) && !reload
    @ldap_entry = ldap.fetch_users(cn: self.cn).first
  end

  def add_to_ldap_array(attr_key, ldap_attr, value)
    current_entries = ldap_entry[attr_key.to_sym] || []
    new_entries = Array(value).map(&:to_s)
    entries = (current_entries + new_entries).uniq.sort
    ldap.replace_attribute(dn, ldap_attr.to_sym, entries)
  end

  def remove_from_ldap_array(attr_key, ldap_attr, value)
    current_entries = ldap_entry[attr_key.to_sym] || []
    entries_to_remove = Array(value).map(&:to_s)
    entries = (current_entries - entries_to_remove).uniq.sort
    ldap.replace_attribute(dn, ldap_attr.to_sym, entries)
  end

  def display_name
    @display_name ||= ldap_entry[:display_name]
  end

  # TODO Variant keys are currently broken for some reason
  # (They use the same key as the main blob, when it should be
  # "/variants/#{key)"
  # def avatar_variant(size: :medium)
  #   dimensions = case size
  #                when :large  then [400, 400]
  #                when :medium then [256, 256]
  #                when :small  then [64, 64]
  #                else [256, 256]
  #                end
  #   format = avatar.content_type == "image/png" ? :png : :jpeg
  #   avatar.variant(resize_to_fill: dimensions, format: format)
  # end

  def nostr_pubkey
    @nostr_pubkey ||= ldap_entry[:nostr_key]
  end

  def nostr_pubkey_bech32
    return nil unless nostr_pubkey.present?
    Nostr::PublicKey.new(nostr_pubkey).to_bech32
  end

  def pgp_pubkey
    @pgp_pubkey ||= ldap_entry[:pgp_key]
  end

  def gnupg_key
    return nil unless pgp_pubkey.present?
    GPGME::Key.import(pgp_pubkey)
    GPGME::Key.get(pgp_fpr)
  end

  def pgp_pubkey_contains_user_address?
    gnupg_key.uids.map(&:email).include?(address)
  end

  def wkd_hash
    ZBase32.encode(Digest::SHA1.digest(cn))
  end

  def services_enabled
    ldap_entry[:services_enabled] || []
  end

  def service_enabled?(name)
    services_enabled.map(&:to_sym).include?(name.to_sym)
  end

  def enable_service(service)
    add_to_ldap_array :services_enabled, :serviceEnabled, service
    ldap_entry(reload: true)[:services_enabled]
  end

  def disable_service(service)
    remove_from_ldap_array :services_enabled, :serviceEnabled, service
    ldap_entry(reload: true)[:services_enabled]
  end

  def disable_all_services
    ldap.delete_attribute(dn, :serviceEnabled)
  end

  def member_status
    ldap_entry[:member_status] || []
  end

  def add_member_status(status)
    add_to_ldap_array :member_status, :memberStatus, status
    ldap_entry(reload: true)[:member_status]
  end

  def remove_member_status(status)
    remove_from_ldap_array :member_status, :memberStatus, status
    ldap_entry(reload: true)[:member_status]
  end

  def is_contributing_member?
    member_status.map(&:to_sym).include?(:contributor)
  end

  def is_paying_member?
    member_status.map(&:to_sym).include?(:sustainer)
  end

  private

    def ldap
      return @ldap_service if defined?(@ldap_service)
      @ldap_service = LdapService.new
    end

    def acceptable_avatar
      return unless avatar_new.present?

      if avatar_new.size > 1.megabyte
        errors.add(:avatar, "must be less than 1MB file size")
      end

      acceptable_types = ["image/jpeg", "image/png"]
      unless acceptable_types.include?(avatar_new.content_type)
        errors.add(:avatar, "must be a JPEG or PNG file")
      end
    end

    def acceptable_pgp_key_format
      unless GPGME::Key.valid?(pgp_pubkey)
        errors.add(:pgp_pubkey, 'is not a valid armored PGP public key block')
      end
    end
end