require 'netrc'
require 'faraday'
require 'json'
require 'acquia_toolbelt/version'

module AcquiaToolbelt
  class CLI
    class API
      USER_AGENT       = "AcquiaToolbelt/#{AcquiaToolbelt::VERSION}"
      ENDPOINT         = 'https://cloudapi.acquia.com'
      ENDPOINT_VERSION = 'v1'

      # Internal: Send a request to the Acquia API.
      #
      # Build a HTTP request to connect to the Acquia API and handle the JSON
      # response accordingly.
      #
      # resource      - The resource URI that is after the version in the API
      #                 URI.
      # method        - HTTP verb to use on the request.
      # data          - Data to send to the endpoint.
      # parse_request - Whether to JSON parse the body before returning or just
      #                 return the whole request object. The whole request is
      #                 returned during tests whereas only the body is required
      #                 for the application.
      #
      # Retuns JSON object from the response body.
      def self.request(resource, method = 'GET', data = {}, parse_request = true)
        # If the netrc file has incorrect permissions, let the user know.
        begin
          n = Netrc.read
        rescue => e
          puts e.message
        end

        # Make sure there is an entry for the Acquia API before generating the
        # requests.
        if n['cloudapi.acquia.com'].nil?
          puts 'No entry for cloudapi.acquia.com within your netrc file.'
          puts 'You can login/reset your user credentials by running `acquia auth:login`'
          return
        end

        @acquia_user, @acquia_password = n['cloudapi.acquia.com']

        # Check if the user is behind a proxy and add the proxy settings if
        # they are.
        conn = (using_proxy?) ? Faraday.new(:proxy => ENV['HTTPS_PROXY']) : Faraday.new
        conn.basic_auth(@acquia_user, @acquia_password)

        # Be nice and send a user agent - help tracking and issue detection on
        # Acquia's end as well as the client.
        conn.headers['User-Agent'] = "#{AcquiaToolbelt::CLI::API::USER_AGENT}"

        case method
        when 'GET'
          response = conn.get "#{endpoint_uri}/#{resource}.json"
          successful_response? response

          if parse_request == true
            JSON.parse(response.body)
          else
            response
          end
        when 'POST'
          response = conn.post "#{endpoint_uri}/#{resource}.json", data.to_json
          successful_response? response

          if parse_request == true
            JSON.parse(response.body)
          else
            response
          end
        when 'QUERY-STRING-POST'
          response = conn.post "#{endpoint_uri}/#{resource}.json?#{data[:key]}=#{data[:value]}", data.to_json
          successful_response? response

          if parse_request == true
            JSON.parse(response.body)
          else
            response
          end
        when 'DELETE'
          response = conn.delete "#{endpoint_uri}/#{resource}.json"
          successful_response? response

          if parse_request == true
            JSON.parse(response.body)
          else
            response
          end
        else
        end
      end

      # Internal: Get defined subscription environments.
      #
      # This is a helper method that fetches all the available environments for
      # a subscription and returns them for use in other methods.
      #
      # Returns an array of environments.
      def self.environments
        subscription = default_subscription
        env_data = request "sites/#{subscription}/envs"

        envs = []
        env_data.each do |env|
          envs << env['name']
        end

        envs
      end

      # Internal: Use the default environment the user has access to.
      #
      # If the -s (subscription) flag is not set, just use the first
      # subscription the user has access to. This is handy for users that
      # primarily only deal with a specific subscription.
      #
      # Returns the first subscription name.
      def self.default_subscription
        sites = request 'sites'
        sites.first
      end

      # Internal: Build the endpoint URI.
      #
      # By building the URI here, we ensure that it is consistent throughout the
      # application and also allows a single point to update should it be
      # needed.
      #
      # Returns a URI string.
      def self.endpoint_uri
        "#{AcquiaToolbelt::CLI::API::ENDPOINT}/#{AcquiaToolbelt::CLI::API::ENDPOINT_VERSION}"
      end

      # Internal: Check whether a proxy is in use.
      #
      # Return boolean based on whether HTTPS_PROXY is set.
      def self.using_proxy?
        ENV['HTTPS_PROXY'] ? true : false
      end

      # Internal: Show the error message from the response.
      #
      # If the API request fails, this will get the "message" and allow that to
      # be outputted to the end user to be a little more helpful.
      #
      # Returns string of the message.
      def self.display_error(response)
        "Oops, an error occurred! Reason: #{response['message']}"
      end

      # Internal: Ensure the response returns a HTTP 200.
      #
      # If the response status isn't a HTTP 200, we need to find out why. This
      # helps identify the issues earlier on and will prevent extra API calls
      # that won't complete.
      #
      # Returns false if the response code isn't a HTTP 200.
      def self.successful_response?(response)
        if response.status != 200
          puts display_error(JSON.parse(response.body))
          return
        end
      end
    end
  end
end