require 'digest'
require 'time'

module Pushlet
  class APNSGateway
    def initialize(o={})
      @mode = o[:mode]
      @pass = o[:p12_pass]
      @pem = o[:pem] || self.class.p12_to_pem_text(o[:p12], o[:p12_pass])
      create_pusher
    end

    def feedback
      feedback = Grocer.feedback(
        certificate: StringIO.new(@pem),
        passphrase:  @pass,
        gateway:     (@mode == "development" ? gateway_sandbox : gateway_production),
        port:        feedback_port,
        retries:     retries
      )

      failed_delivery_attempts = []

      feedback.each do |fda|
        failed_delivery_attempts << fda
      end

      failed_delivery_attempts
    end

    def create_pusher
      @pusher = Grocer.pusher(
        certificate: StringIO.new(@pem),
        passphrase:  @pass,
        gateway:     (@mode == "development" ? gateway_sandbox : gateway_production),
        port:        port,
        retries:     retries
      )
    end

    def gateway_sandbox;    'gateway.sandbox.push.apple.com' end
    def gateway_production; 'gateway.push.apple.com' end
    def port;               2195 end
    def feedback_port;      2196 end
    def retries;            3 end

    def push(args={})
      if args[:identifier]
        identifier = args[:identifier]
      else
        # Seriously Apple, a 4 byte identifier? Really guys?
        identifier = SecureRandom.random_bytes(4)
      end

      payload = {}
      
      [:device_token, :alert, :badge, :sound, :expiry, :identifier].each do |a|
        if a == :expiry
          payload[a] = args[a] || Time.now + 60*10
        else
          payload[a] = args[a] if args[a]
        end
      end

      notification = Grocer::Notification.new payload

      @pusher.push(notification)
    end

    def self.p12_to_pem_text(p12, p12_pass='')
      p12_pass = '' if p12_pass.nil?

      if Running.jruby?
        tf_p12 = Tempfile.new 'tf_p12'
        tf_p12.write p12
        tf_p12.rewind
        tf_p12.close

        tf_pem = Tempfile.new 'tf_pem'
        tf_pem.close

        cmd = Escape.shell_command(['openssl', 'pkcs12', '-in', tf_p12.path, '-out', tf_pem.path,
                                    '-nodes', '-clcerts', '-password', 'pass:'+p12_pass]).to_s + ' &> /dev/null'

        begin
          result = system cmd
          raise CommandFailError if result.nil? || result == false
          pem = File.read tf_pem.path
        ensure
          tf_pem.unlink
          tf_p12.unlink
        end

        pem
      else
        pkcs12 = OpenSSL::PKCS12.new p12, p12_pass
        pkcs12.certificate.to_s + pkcs12.key.to_s
      end
    end
  end
end