require "sinbotra"
require "sinatra"
require "json"

require "sinbotra/messenger/middleware/facebook_signature"
require "sinbotra/messenger/middleware/parse_message"

module Sinbotra

  class Server < Sinatra::Base
    use Sinbotra::Messenger::Middleware::FacebookSignature
    use Sinbotra::Messenger::Middleware::ParseMessage

    configure do
      raise ArgumentError, "You need to set a FACEBOOK_CHALLENGE environmental variable to run the server!"  unless ENV["FACEBOOK_CHALLENGE"]
      set :facebook_handler, Sinbotra::MessageHandler.new(:facebook)
      Sinbotra::Bot::UserRepo.connect
    end

    helpers do
      def match_facebook_challenge(params)
        matching = params["hub.mode"] == "subscribe" &&
                   params["hub.verify_token"] == ENV.fetch("FACEBOOK_CHALLENGE")
        matching ? params["hub.challenge"] : nil
      end
    end

    get "/facebook/webhook" do
      if challenge = match_facebook_challenge(params)
        challenge
      else
        status 403
      end
    end

    post "/facebook/webhook" do
      begin
        msgs    = request.env["facebook.messages"]
        settings.facebook_handler.receive_messages(msgs)
        status 200
        "OK"
      rescue Exception => e
        STDERR.puts e.message
        STDERR.puts e.backtrace
        status 200
        "ERROR"
      end
    end
  end
end