#!/usr/bin/env ruby

# TODO - Repeated params

require 'thor'
require 'open-uri'
require 'google/apis/discovery_v1'
require 'google/apis/generator'
require 'multi_json'
require 'logger'

module Google
  class ApiGenerator < Thor
    include Thor::Actions

    Google::Apis::ClientOptions.default.application_name = "generate-api"
    Google::Apis::ClientOptions.default.application_version = Google::Apis::VERSION

    Discovery = Google::Apis::DiscoveryV1

    desc 'gen OUTDIR', 'Generate ruby API from an API description'
    method_options url: :string, file: :string, id: :array, preferred_only: :boolean, verbose: :boolean, names: :string, names_out: :string
    method_option :preferred_only, default: true
    def gen(dir)
      self.destination_root = dir
      Google::Apis.logger.level = Logger::DEBUG if options[:verbose]
      if options[:url]
        generate_from_url(options[:url])
      elsif options[:file]
        generate_from_file(options[:file])
      else
        generate_from_discovery(preferred_only: options[:preferred_only], id: options[:id] )
      end
      create_file(options[:names_out]) { |*| generator.dump_api_names } if options[:names_out]
    end

    desc 'list', 'List public APIs'
    method_options verbose: :boolean, preferred_only: :boolean
    def list
      Google::Apis.logger.level = Logger::DEBUG if options[:verbose]
      discovery = Discovery::DiscoveryService.new
      apis = discovery.list_apis
      apis.items.each do |api|
        say sprintf('%s - %s', api.id, api.description).strip unless options[:preferred_only] && !api.preferred?
      end
    end

    no_commands do
      def generate_from_url(url)
        json = discovery.http(:get, url)
        generate_api(json)
      end

      def generate_from_file(file)
        File.open(file) do |f|
          generate_api(f.read)
        end
      end

      def generate_from_discovery(preferred_only: false, id: nil)
        say 'Fetching API list'
        id = Array(id)
        apis = discovery.list_apis
        apis.items.each do |api|
          if (id.empty? && preferred_only && api.preferred?) || id.include?(api.id)
            say sprintf('Loading %s, version %s from %s', api.name, api.version, api.discovery_rest_url)
            generate_from_url(api.discovery_rest_url)
          else
            say sprintf('Ignoring disoverable API %s', api.id)
          end
        end
      end

      def generate_api(json)
        files = generator.render(json)
        files.each do |file, content|
          create_file(file) { |*| content }
        end
      end

      def discovery
        @discovery ||= Discovery::DiscoveryService.new
      end

      def generator
        @generator ||= Google::Apis::Generator.new(api_names: options[:names])
      end
    end
  end

end

Google::ApiGenerator.start(ARGV)