require 'httparty'
require 'multi_xml'

module Rundeck
  # @private
  class Request
    include HTTParty

    format :xml
    attr_accessor :api_token

    def get(path, options = {})
      request_settings(options)
      validate self.class.get(path, options)
    end

    def post(path, options = {})
      request_settings(options, path)
      validate self.class.post(path, options)
    end

    def put(path, options = {})
      request_settings(options)
      validate self.class.put(path, options)
    end

    def delete(path, options = {})
      request_settings(options)
      validate self.class.delete(path, options)
    end

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

      handle_response(response)
    end

    # Sets a base_uri and default_params for requests.
    # @raise [Error::MissingCredentials] if endpoint not set.
    def set_request_defaults(endpoint, api_token)
      unless endpoint
        fail Error::MissingCredentials, 'Please set an endpoint to API'
      end
      @api_token = api_token

      self.class.base_uri "#{endpoint}/api/#{Rundeck.api_version}"
    end

    private

    def request_settings(options, path = nil)
      api_token_header(options, path)
      accept_header(options)
    end

    # Sets a PRIVATE-TOKEN header for requests.
    # @raise [Error::MissingCredentials] if api_token not set.
    def api_token_header(options, path = nil)
      return nil if path == '/j_security_check'
      unless @api_token
        fail Error::MissingCredentials, 'Please set a api_token for user'
      end
      options[:headers] = {} if options[:headers].nil?
      options[:headers].merge!('X-Rundeck-Auth-Token' => @api_token)
    end

    def accept_header(options)
      return nil if options[:headers].nil?

      unless options[:headers].include?('Accept')
        options[:headers].merge!('Accept' => 'application/xml')
      end
    end

    def handle_response(response)
      response.parsed_response
    rescue MultiXml::ParseError
      raise Error::Parsing, 'An unexpected error occurred. Please try again'
    end

    def error_message(response)
      message = if response.parsed_response && response.parsed_response['result']
                  response.parsed_response['result']['error'][1]['message']
                else
                  'none'
                end

      "Server responded with code #{response.code}, " \
      "message: #{message}. " \
      "Request URI: #{response.request.base_uri}#{response.request.path}"
    end
  end
end