require 'httparty'
require 'dingbot/message/base'

module DingBot
  # @private
  class Client
    include HTTParty

    format :json
    headers "Content-Type" => "application/json"

    attr_accessor :access_token

    def initialize(access_token='')
      @access_token = access_token
    end

    # Parse response body.
    def self.parse(body)
      begin
        decode(body)
      rescue => e
        raise Error::Parsing.new "Couldn't parse a response body"
      end
    end

    # Decodes a JSON response into Ruby object.
    def self.decode(response)
      JSON.load response
    rescue JSON::ParserError
      raise Error::Parsing.new "The response is not a valid JSON"
    end

    def send_msg(message)
      validate self.class.post(DingBot::ENDPOINT, {query: {access_token: @access_token}, body: message.to_json})
    end

    # Checks the response code for common errors.
    # Returns parsed response for successful requests.
    def validate(response)
      error_klass = case response.code
                      when 400 then
                        Error::BadRequest
                      when 401 then
                        Error::Unauthorized
                      when 403 then
                        Error::Forbidden
                      when 404 then
                        Error::NotFound
                      when 405 then
                        Error::MethodNotAllowed
                      when 409 then
                        Error::Conflict
                      when 422 then
                        Error::Unprocessable
                      when 500 then
                        Error::InternalServerError
                      when 502 then
                        Error::BadGateway
                      when 503 then
                        Error::ServiceUnavailable
                    end

      fail error_klass.new(response) if error_klass

      parsed = response.parsed_response
      parsed.client = self if parsed.respond_to?(:client=)
      parsed.parse_headers!(response.headers) if parsed.respond_to?(:parse_headers!)
      parsed
    end

  end
end