require "rqrcode"

class WalletController < ApplicationController
  before_action :require_user_signed_in
  before_action :authenticate_with_lndhub
  before_action :set_current_section
  before_action :fetch_balance

  def index
    @wallet_url = "lndhub://#{current_user.ln_account}:#{current_user.ln_password}@#{ENV['LNDHUB_PUBLIC_URL']}"

    qrcode = RQRCode::QRCode.new(@wallet_url)
    @svg = qrcode.as_svg(
      color: "000",
      shape_rendering: "crispEdges",
      module_size: 6,
      standalone: true,
      use_path: true,
      svg_attributes: {
        class: 'inline-block'
      }
    )
  end

  def transactions
    @transactions = fetch_transactions
  end

  private

  def authenticate_with_lndhub(options={})
    if session[:ln_auth_token].present? && !options[:force_reauth]
      @ln_auth_token = session[:ln_auth_token]
    else
      lndhub = Lndhub.new
      auth_token = lndhub.authenticate(current_user)
      session[:ln_auth_token] = auth_token
      @ln_auth_token = auth_token
    end
  rescue
    # TODO add exception tracking
  end

  def set_current_section
    @current_section = :wallet
  end

  def fetch_balance
    lndhub = Lndhub.new
    data = lndhub.balance @ln_auth_token
    @balance = data["BTC"]["AvailableBalance"] rescue nil
  rescue
    authenticate_with_lndhub(force_reauth: true)
    return nil if @fetch_balance_retried
    @fetch_balance_retried = true
    fetch_balance
  end

  def fetch_transactions
    lndhub = Lndhub.new
    txs = lndhub.gettxs @ln_auth_token
    invoices = lndhub.getuserinvoices(@ln_auth_token).select{|i| i["ispaid"]}
    process_transactions(txs + invoices)
  rescue
    authenticate_with_lndhub(force_reauth: true)
    return [] if @fetch_transactions_retried
    @fetch_transactions_retried = true
    fetch_transactions
  end

  def process_transactions(txs)
    txs.collect do |tx|
      if tx["type"] == "bitcoind_tx"
        tx["amount_sats"] = (tx["amount"] * 100000000).to_i
        tx["datetime"] = Time.at(tx["time"].to_i)
        tx["title"] = "Received"
        tx["description"] = "On-chain topup"
        tx["received"] = true
      else
        tx["amount_sats"] = tx["value"] || tx["amt"]
        tx["datetime"] = Time.at(tx["timestamp"].to_i)
        tx["title"] = tx["type"] == "paid_invoice" ? "Sent" : "Received"
        tx["description"] = tx["memo"] || tx["description"]
        tx["received"] = tx["type"] == "user_invoice"
      end
    end

    txs.sort{ |a,b| b["datetime"] <=> a["datetime"] }
  end
end