module Apphunkd
  class Queue

    attr_accessor :items
    attr_accessor :mutex
    attr_accessor :worker

    def initialize
      @items = []
      @mutex = Mutex.new
    end

    def activate!
      @worker = initialize_worker
    end

    def store(message = {})
      debug "Receive: #{message.inspect}"
      return false if message[:message].blank? || message[:token].blank?
      message[:stored_at] = Time.now

      @mutex.synchronize do
        @items = @items[-9999..-1] if @items.size >= 9999
        @items << message
      end

      @worker.wakeup
      return true
    end

    def initialize_worker
      Thread.new do
        begin
          loop do
            unless @items.empty?
              items = get_items_from_stack
              items.each do |item|
                result = push_item_to_remote_service(item)
                if result.status == :ok
                  case result.response.code
                  when '201'
                    debug "Message successfully stored."
                  when '400', '403'
                    log_error "Remote Service refused to store item: #{result.response.code} / #{result.response.body}. Dropped."
                  else
                    put_item_to_stack(item)
                    log_error "Remote Service went crazy. Put item back in queue: #{result.response.code} / #{result.response.body}"
                  end
                else
                  put_item_to_stack(item)
                  log_error "Could not push to Remote Service: Connection Error. Put item back in queue."
                end
              end
            end
            sleep
          end
        rescue => e
          log_error "Error: #{e}"
        end
      end
    end


    private

      def get_items_from_stack
        copied_items = []
        @mutex.synchronize do
          copied_items = @items.dup
          @items.clear
        end
        return copied_items
      end

      def put_item_to_stack(item)
        @mutex.synchronize { @items << item }
      end

      def push_item_to_remote_service(item)
        url = generate_api_messages_url(item.delete('token'))
        result = Apphunkd::Remote.post(url, item, 300)
      end

      def generate_api_messages_url(token)
        path = "v1/#{token}/messages"
        if DaemonKit.env.to_s == 'production'
          "http://postbox.apphunk.com/#{path}"
        else
          "http://postbox.apphunk.local/#{path}"
        end
      end

      def debug(message)
        if DaemonKit.env.to_s == 'development' || ENV['DEBUG']
          DaemonKit.logger.debug message
        end
      end

      def log_error(message)
        DaemonKit.logger.info message
      end
  end
end