require "em-twitter"
require "yajl"
require "msgpack"
require "./settings"
require "./logger"

class Worker
  class DBProxyClient < EM::Connection
    def send_object(data)
      send_data(data.to_msgpack)
    end

    def initialize
      @clients = {}
      @pac = MessagePack::Unpacker.new
    end

    def format_text(status)
      chars = status[:text].to_s.split(//)

      entities = status[:entities].values.flatten.sort_by{|entity| entity[:indices].first}

      result = []
      last_index = entities.inject(0) do |last_index, entity|
        result << chars[last_index...entity[:indices].first]
        result << if entity[:url]
                    "<url:#{CGI.escape(entity[:expanded_url])}:#{CGI.escape(entity[:display_url])}>"
                  elsif entity[:text]
                    "<hashtag:#{CGI.escape(entity[:text])}>"
                  elsif entity[:screen_name]
                    "<mention:#{CGI.escape(entity[:screen_name])}>"
                  elsif entity[:cashtag]
                    "<cashtag:#{CGI.escape(entity[:cashtag])}>"
                  end
        entity[:indices].last
      end
      result << chars[last_index..-1]

      result.flatten.join
    end

    def format_source(status)
      if status[:source].index("<a")
        url = status[:source].scan(/href="(.+?)"/).flatten.first
        name = status[:source].scan(/>(.+?)</).flatten.first
        "<url:#{CGI.escape(url)}:#{CGI.escape(name)}>"
      else
        status[:source]
      end
    end

    def receive_account(msg)
      user_id = msg["user_id"]
      account_id = msg["id"]
      if @clients[account_id]
        @clients[account_id].connection.stop
        @clients.delete(account_id)
      end
      @clients[account_id] = client = EM::Twitter::Client.new({
        :host => "userstream.twitter.com",
        :path => "/1.1/user.json",
        :oauth => {
          :consumer_key => Settings.consumer[msg["consumer_version"].to_i].key,
          :consumer_secret => Settings.consumer[msg["consumer_version"].to_i].secret,
          :token => msg["oauth_token"],
          :token_secret => msg["oauth_token_secret"]},
        :method => "GET"})

      send_user = -> user do
        out = {:type => "user",
               :id => user[:id],
               :screen_name => user[:screen_name],
               :name => user[:name],
               :profile_image_url => user[:profile_image_url_https],
               :protected => user[:protected]}
        send_object(out)
        $logger.debug("User(##{account_id}/#{user_id}): #{user[:id]} = #{user[:screen_name]}")
      end

      send_tweet = -> status do
        send_user.call(status[:user])
        out = {:type => "tweet",
               :id => status[:id],
               :text => format_text(status),
               :source => format_source(status),
               :tweeted_at => status[:created_at],
               :user_id => status[:user][:id]}
        send_object(out)
        $logger.debug("Tweet(##{account_id}/#{user_id}): #{status[:id]}")
      end

      send_favorite = -> source, target_object do
        send_tweet.call(target_object)
        send_user.call(source)
        out = {:type => "favorite",
               :tweet_id => target_object[:id],
               :user_id => source[:id]}
        send_object(out)
        $logger.debug("Favorite(##{account_id}/#{user_id}): #{source[:id]} => #{target_object[:id]}")
      end

      send_unfavorite = -> source, target_object do
        out = {:type => "delete",
               :tweet_id => target_object[:id],
               :user_id => source[:id]}
        send_object(out)
        $logger.debug("Unfavorite(##{account_id}/#{user_id}): #{source[:id]} => #{target_object[:id]}")
      end

      send_retweet = -> status do
        send_tweet.call(status[:retweeted_status])
        send_user.call(status[:user])
        out = {:type => "retweet",
               :id => status[:id],
               :tweet_id => status[:retweeted_status][:id],
               :user_id => status[:user][:id]}
        send_object(out)
        $logger.debug("Retweet(##{account_id}/#{user_id}): #{status[:user][:id]} => #{status[:retweeted_status][:id]}")
      end

      send_delete = -> deleted_status_id, deleted_user_id do
        out = {:type => "delete",
               :id => deleted_status_id,
               :user_id => deleted_user_id}
        send_object(out)
        $logger.debug("Delete(##{account_id}/#{user_id}): #{deleted_user_id} => #{deleted_status_id}")
      end

      client.on_error do |message|
        $logger.warn("Unknown Error(##{account_id}/#{user_id}): #{message}")
      end

      client.on_unauthorized do
        # revoked?
        $logger.warn("Unauthorized(##{account_id}/#{user_id})")
        out = {:type => "unauthorized", :user_id => user_id, :id => account_id}
        send_object(out)
        client.connection.stop
        @clients.delete(account_id)
      end

      client.on_enhance_your_calm do
        # limit?
        $logger.warn("Enhance your calm(##{account_id}/#{user_id})")
      end

      client.on_no_data_received do
        # (?)
        $logger.warn("No data received(##{account_id}/#{user_id})")
        client.close_connection
      end

      client.each do |chunk|
        begin
          hash = Yajl::Parser.parse(chunk, :symbolize_keys => true)
        rescue Yajl::ParseError
          $logger.warn("Unexpected chunk(##{account_id}/#{user_id}): #{chunk}")
          next
        end

        if hash[:warning]
          $logger.info("Stall warning(##{account_id}/#{user_id}): #{hash[:warning]}")
        elsif hash[:delete] && hash[:delete][:status]
          deleted_status_id = hash[:delete][:status][:id]
          deleted_user_id = hash[:delete][:status][:user_id]
          send_delete.call(deleted_status_id, deleted_user_id)
        elsif hash[:limit]
          $logger.warn("UserStreams Limit Event(##{account_id}/#{user_id}): #{hash[:limit][:track]}")
        elsif hash[:event]
          case hash[:event]
          when "favorite"
            source = hash[:source]
            target_object = hash[:target_object]
            if !target_object[:user][:protected] ||
                target_object[:user][:id] == user_id
              send_favorite.call(source, target_object)
            end
          when "unfavorite"
            send_unfavorite.call(hash[:source], hash[:target_object])
          end
        elsif hash[:user]
          # tweet
          if hash[:retweeted_status]
            if hash[:retweeted_status][:user][:id] == user_id ||
                hash[:user][:id] == user_id
              send_retweet.call(hash)
            end
          elsif hash[:user][:id] == user_id
            send_tweet.call(hash)
          end
        elsif hash[:friends]
          # monyo
        else
          $logger.debug("??(##{account_id}/#{user_id})")
        end
      end

      client.on_reconnect do |timeout, retries|
        $logger.warn("Reconnected(##{account_id}/#{user_id}): #{retries}")
      end

      client.on_max_reconnects do |timeout, retries|
        $logger.warn("Max reconnects(##{account_id}/#{user_id}): #{retries}")
        client.connection.stop
        @clients.delete(account_id)
      end

      client.connect
      $logger.info("Connected(##{account_id}/#{user_id})")
    end

    def post_init
      out = {:type => "init",
             :secret_key => Settings.secret_key,
             :worker_number => Settings.worker_number}
      send_object(out)
    end

    def unbind
      $logger.info("Connection closed")
      EM.add_timer(10) do
        reconnect(Settings.db_proxy_host, Settings.db_proxy_port)
        post_init
      end
    end

    def receive_data(data)
      @pac.feed_each(data) do |msg|
        unless msg.is_a?(Hash) && msg["type"]
          $logger.warn("Unknown data: #{msg}")
          return
        end

        case msg["type"]
        when "ok"
          $logger.info("ok: #{msg["message"]}")
        when "error"
          $logger.info("error: #{msg["message"]}")
        when "fatal"
          $logger.info("fatal: #{msg["message"]}")
        when "bye"
          $logger.info("bye: #{msg["message"]}")
        when "account"
          begin
            receive_account(msg)
          rescue
            $logger.error($!)
            $logger.error($@)
          end
        else
          $logger.info("Unknown message type: #{msg}")
        end
      end
    end

    def stop_all
      @clients.map{|k, v| v.connection.stop}
      send_object({:type => "quit", :reason => "stop_all"})
    end
  end

  def initialize
    $logger = Aclog::Logger.new(:info)
  end

  def start
    $logger.info("Worker ##{Settings.worker_number} started")
    EM.run do
      connection = EM.connect(Settings.db_proxy_host, Settings.db_proxy_port, DBProxyClient)

      stop = Proc.new do
        connection.stop_all
        EM.stop
      end
      Signal.trap(:INT, &stop)
      Signal.trap(:TERM, &stop)
    end
  end
end