module FiveMobilePush
  # @todo Validate provided platforms
  # @todo Simplify platform selection
  class Notifier

    # The following are platforms supported by the Five Mobile Push platform

    ALL        = "all"
    IPHONE     = "iphone"
    BLACKBERRY = "blackberry"
    ANDROID    = "android"

    # @param [FiveMobilePush::Client] client The Client object to use when
    #   sending notices
    def initialize(client)
      @client = client
    end

    # Broadcast a notification to one or more platforms of an application.
    #
    # == Supported Platforms
    #
    # * all
    # * iphone
    # * blackberry
    # * android
    #
    # @param [Array<String>, String] platforms Any of the supported platforms.
    #
    # @yield [message] Provides a mini-DSL for constructing the message to
    #   broadcast.
    #
    # @yieldparam [Message] message (see Message)
    #
    # @example Simple usage
    #   n = FiveMobilePush::Notifier.new(client)
    #   n.broadcast(FiveMobilePush::Notifier::ALL) do |message|
    #     message.body "Downtime this weekend"
    #   end
    def broadcast(platforms, &block)
      @client.post 'notify/broadcast',
        :platforms => build_platforms_string(platforms),
        :payload   => capture_message(&block).to_json
    end

    # Send a notification to any number of specified devices
    #
    # @param [Array<String>] devices A list of device ID values
    #
    # @yield [message] Provides a mini-DSL for constructing the message to
    #   broadcast.
    #
    # @yieldparam [Message] message (see Message)
    #
    # @example Simple usage
    #   n = FiveMobilePush::Notifier.new(client)
    #   n.notify_devices(['1234']) do |message|
    #     message.body "Downtime this weekend"
    #   end
    def notify_devices(devices, &block)
      @client.post 'notify/toDevices',
        :id_type   => FiveMobilePush::DEFAULT_ID_TYPE,
        :id_values => devices.join(','),
        :payload   => capture_message(&block).to_json
    end

    # Notifies any device registered with the provided tags.
    #
    # == Supported Platforms
    #
    # * all
    # * iphone
    # * blackberry
    # * android
    #
    # @param [Array<String>, String] platforms Any of the supported platforms.
    # @param [Array<String>] tags Any tag that is registered
    #
    # @yield [message] Provides a mini-DSL for constructing the message to
    #   broadcast.
    #
    # @yieldparam [Message] message (see Message)
    #
    # @example Simple usage
    #   n = FiveMobilePush::Notifier.new(client)
    #   n.notify_by_tags(FiveMobilePush::Notifier::ALL, ['muffin', 'bacon']) do |message|
    #     message.body "Downtime this weekend"
    #   end
    def notify_by_tags(platforms, tags, &block)
      @client.post 'notify/toTags',
        :platforms => build_platforms_string(platforms),
        :tags      => tags.join(','),
        :payload   => capture_message(&block).to_json
    end

    # Simple proxy class for building messages. Do not use this class directly.
    class Message
      # @param [String] body The text to send
      def body(body)
        @body = body
      end

      # @param [Hash] meta_data (optional) The optional meta data to send.
      def meta_data(meta_data)
        @meta_data = meta_data
      end

      # @private
      def to_payload
        FiveMobilePush::Payload.new(@message, @meta_data)
      end
    end

    private

    def capture_message(&block)
      payload_proxy = Message.new
      block.call(payload_proxy)
      payload_proxy.to_payload
    end

    def build_platforms_string(platforms)
      if platforms.kind_of?(Enumerable)
        platforms.join(',')
      else
        platforms.to_s
      end
    end

  end
end