# frozen_string_literal: true

# Copyright 2018 Google LLC
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     https://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

require "gapic/file_formatter"
require "action_controller"
require "google/protobuf/compiler/plugin.pb"
require "tempfile"

module Gapic
  module Generators
    # The generator orchestrates the rendering of templates.
    class BaseGenerator
      # Initializes the generator.
      #
      # @param api [Gapic::Schema::Api] The API model/context to
      #   generate.
      def initialize api
        @api = api
      end

      # Generates all the files for the API.
      #
      # @return [Array<
      #   Google::Protobuf::Compiler::CodeGeneratorResponse::File>]
      #   The files that were generated for the API.
      def generate
        raise "must implement"
      end

      private

      def use_templates! template_path
        template_path = File.expand_path template_path
        helpers_path = File.join template_path, "helpers"

        # Configure Dependencies to know how to load helpers
        ActiveSupport::Dependencies.autoload_paths.prepend helpers_path

        # Configure the controller to know about the templates and helpers
        controller.prepend_view_path template_path
        controller.class.helper \
          controller.class.all_helpers_from_path helpers_path
      end

      def controller
        # Each controller gets a new class, so multiple generators can be
        # active at the same time without stomping on each other.
        @controller ||= Class.new(ActionController::Base).new
      end

      def generate_file template, filename, **args
        content = controller.render_to_string(
          template: template, formats: :text, locals: args
        )
        Google::Protobuf::Compiler::CodeGeneratorResponse::File.new(
          name: filename, content: content
        )
      end
      alias_method :g, :generate_file

      def format_files files
        FileFormatter.new(format_config, files).files
      end

      def format_config
        File.expand_path File.join __dir__, "../../../default-rubocop.yml"
      end
    end
  end
end