# frozen_string_literal: true

require "fileutils"

module ReactOnRails
  # rubocop:disable Metrics/ClassLength
  class PacksGenerator
    CONTAINS_CLIENT_OR_SERVER_REGEX = /\.(server|client)($|\.)/.freeze
    MINIMUM_SHAKAPACKER_MAJOR_VERSION = 6
    MINIMUM_SHAKAPACKER_MINOR_VERSION = 5
    MINIMUM_SHAKAPACKER_PATCH_VERSION = 1

    def self.generate
      packs_generator = PacksGenerator.new
      packs_generator.verify_setup_and_generate_packs
    end

    def self.raise_nested_enteries_disabled
      packs_generator = PacksGenerator.new
      packs_generator.raise_nested_enteries_disabled
    end

    def verify_setup_and_generate_packs
      return unless components_subdirectory.present?

      raise_webpacker_not_installed unless ReactOnRails::WebpackerUtils.using_webpacker?
      raise_shakapacker_version_incompatible unless shackapacker_version_requirement_met?
      raise_nested_enteries_disabled unless ReactOnRails::WebpackerUtils.nested_entries?

      is_generated_directory_present = Dir.exist?(generated_packs_directory_path)

      return if is_generated_directory_present && webpack_assets_status_checker.stale_generated_component_packs.empty?

      clean_generated_packs_directory
      generate_packs
    end

    def raise_nested_enteries_disabled
      msg = <<~MSG
        **ERROR** ReactOnRails: `nested_entries` is configured to be disabled in shakapacker. Please update \
        webpacker.yml to enable nested enteries. for more information read
        https://www.shakacode.com/react-on-rails/docs/guides/file-system-based-automated-bundle-generation.md#enable-nested_entries-for-shakapacker
      MSG

      raise ReactOnRails::Error, msg
    end

    private

    def generate_packs
      common_component_to_path.each_value { |component_path| create_pack(component_path) }
      client_component_to_path.each_value { |component_path| create_pack(component_path) }

      create_server_pack if ReactOnRails.configuration.server_bundle_js_file.present?
    end

    def create_pack(file_path)
      output_path = generated_pack_path(file_path)
      content = pack_file_contents(file_path)

      File.write(output_path, content)

      puts(Rainbow("Generated Packs: #{output_path}").yellow)
    end

    def pack_file_contents(file_path)
      registered_component_name = component_name(file_path)
      <<~FILE_CONTENT
        import ReactOnRails from 'react-on-rails';
        import #{registered_component_name} from '#{relative_component_path_from_generated_pack(file_path)}';

        ReactOnRails.register({#{registered_component_name}});
      FILE_CONTENT
    end

    def create_server_pack
      File.write(generated_server_bundle_file_path, generated_server_pack_file_content)

      add_generated_pack_to_server_bundle
      puts(Rainbow("Generated Server Bundle: #{generated_server_bundle_file_path}").orange)
    end

    def generated_server_pack_file_content
      common_components_for_server_bundle = common_component_to_path.delete_if { |k| server_component_to_path.key?(k) }
      component_for_server_registration_to_path = common_components_for_server_bundle.merge(server_component_to_path)

      server_component_imports = component_for_server_registration_to_path.map do |name, component_path|
        "import #{name} from '#{relative_path(generated_server_bundle_file_path, component_path)}';"
      end

      components_to_register = component_for_server_registration_to_path.keys

      <<~FILE_CONTENT
        import ReactOnRails from 'react-on-rails';

        #{server_component_imports.join("\n")}

        ReactOnRails.register({#{components_to_register.join(",\n")}});
      FILE_CONTENT
    end

    def add_generated_pack_to_server_bundle
      relative_path_to_generated_server_bundle = relative_path(defined_server_bundle_file_path,
                                                               generated_server_bundle_file_path)
      content = <<~FILE_CONTENT
        import "./#{relative_path_to_generated_server_bundle}"\n
      FILE_CONTENT

      prepend_to_file_if_not_present(defined_server_bundle_file_path, content)
    end

    def generated_server_bundle_file_path
      file_ext = File.extname(defined_server_bundle_file_path)
      generated_server_bundle_file_path = defined_server_bundle_file_path.sub(file_ext, "-generated#{file_ext}")
      generated_server_bundle_file_name = component_name(generated_server_bundle_file_path)
      source_entry_path = ReactOnRails::WebpackerUtils.webpacker_source_entry_path

      "#{source_entry_path}/#{generated_server_bundle_file_name}#{file_ext}"
    end

    def clean_generated_packs_directory
      FileUtils.rm_rf(generated_packs_directory_path)
      FileUtils.mkdir_p(generated_packs_directory_path)
    end

    def defined_server_bundle_file_path
      ReactOnRails::Utils.server_bundle_js_file_path
    end

    def generated_packs_directory_path
      source_entry_path = ReactOnRails::WebpackerUtils.webpacker_source_entry_path

      "#{source_entry_path}/generated"
    end

    def relative_component_path_from_generated_pack(ror_component_path)
      component_file_pathname = Pathname.new(ror_component_path)
      component_generated_pack_path = generated_pack_path(ror_component_path)
      generated_pack_pathname = Pathname.new(component_generated_pack_path)

      relative_path(generated_pack_pathname, component_file_pathname)
    end

    def relative_path(from, to)
      from_path = Pathname.new(from)
      to_path = Pathname.new(to)

      relative_path = to_path.relative_path_from(from_path)
      relative_path.sub("../", "")
    end

    def generated_pack_path(file_path)
      "#{generated_packs_directory_path}/#{component_name(file_path)}.jsx"
    end

    def component_name(file_path)
      basename = File.basename(file_path, File.extname(file_path))

      basename.sub(CONTAINS_CLIENT_OR_SERVER_REGEX, "")
    end

    def component_name_to_path(paths)
      paths.to_h { |path| [component_name(path), path] }
    end

    def common_component_to_path
      common_components_paths = Dir.glob("#{components_search_path}/*").reject do |f|
        CONTAINS_CLIENT_OR_SERVER_REGEX.match?(f)
      end
      component_name_to_path(common_components_paths)
    end

    def client_component_to_path
      client_render_components_paths = Dir.glob("#{components_search_path}/*.client.*")
      client_specific_components = component_name_to_path(client_render_components_paths)

      duplicate_components = common_component_to_path.slice(*client_specific_components.keys)
      duplicate_components.each_key { |component| raise_client_component_overrides_common(component) }

      client_specific_components
    end

    def server_component_to_path
      server_render_components_paths = Dir.glob("#{components_search_path}/*.server.*")
      server_specific_components = component_name_to_path(server_render_components_paths)

      duplicate_components = common_component_to_path.slice(*server_specific_components.keys)
      duplicate_components.each_key { |component| raise_server_component_overrides_common(component) }

      server_specific_components.each_key do |k|
        raise_missing_client_component(k) unless client_component_to_path.key?(k)
      end

      server_specific_components
    end

    def components_search_path
      source_path = ReactOnRails::WebpackerUtils.webpacker_source_path

      "#{source_path}/**/#{components_subdirectory}"
    end

    def components_subdirectory
      ReactOnRails.configuration.components_subdirectory
    end

    def webpack_assets_status_checker
      source_path = ReactOnRails::Utils.source_path
      generated_assets_full_path = ReactOnRails::Utils.generated_assets_full_path
      webpack_generated_files = ReactOnRails.configuration.webpack_generated_files

      @webpack_assets_status_checker ||= ReactOnRails::TestHelper::WebpackAssetsStatusChecker.new(
        source_path: source_path,
        generated_assets_full_path: generated_assets_full_path,
        webpack_generated_files: webpack_generated_files
      )
    end

    def raise_client_component_overrides_common(component_name)
      msg = <<~MSG
        **ERROR** ReactOnRails: client specific definition for Component '#{component_name}' overrides the \
        common definition. Please delete the common definition and have separate server and client files. For more \
        information, please see https://www.shakacode.com/react-on-rails/docs/guides/file-system-based-automated-bundle-generation.md
      MSG

      raise ReactOnRails::Error, msg
    end

    def raise_server_component_overrides_common(component_name)
      msg = <<~MSG
        **ERROR** ReactOnRails: server specific definition for Component '#{component_name}' overrides the \
        common definition. Please delete the common definition and have separate server and client files. For more \
        information, please see https://www.shakacode.com/react-on-rails/docs/guides/file-system-based-automated-bundle-generation.md
      MSG

      raise ReactOnRails::Error, msg
    end

    def raise_missing_client_component(component_name)
      msg = <<~MSG
        **ERROR** ReactOnRails: Component '#{component_name}' is missing a client specific file. For more \
        information, please see https://www.shakacode.com/react-on-rails/docs/guides/file-system-based-automated-bundle-generation.md
      MSG

      raise ReactOnRails::Error, msg
    end

    def raise_shakapacker_version_incompatible
      msg = <<~MSG
        **ERROR** ReactOnRails: Please upgrade Shakapacker to version #{minimum_required_shakapacker_version} or \
        above to use the automated bundle generation feature. The currently installed version is \
        #{ReactOnRails::WebpackerUtils.shakapacker_version}.
      MSG

      raise ReactOnRails::Error, msg
    end

    def raise_webpacker_not_installed
      msg = <<~MSG
        **ERROR** ReactOnRails: Missing Shakapacker gem. Please upgrade to use Shakapacker \
        #{minimum_required_shakapacker_version} or above to use the \
        automated bundle generation feature.
      MSG

      raise ReactOnRails::Error, msg
    end

    def shakapacker_major_minor_version
      shakapacker_version = ReactOnRails::WebpackerUtils.shakapacker_version
      match = shakapacker_version.match(ReactOnRails::VersionChecker::MAJOR_MINOR_PATCH_VERSION_REGEX)

      [match[1].to_i, match[2].to_i, match[3].to_i]
    end

    def shackapacker_version_requirement_met?
      major = shakapacker_major_minor_version[0]
      minor = shakapacker_major_minor_version[1]
      patch = shakapacker_major_minor_version[2]

      major >= MINIMUM_SHAKAPACKER_MAJOR_VERSION && minor >= MINIMUM_SHAKAPACKER_MINOR_VERSION &&
        patch >= MINIMUM_SHAKAPACKER_PATCH_VERSION
    end

    def minimum_required_shakapacker_version
      "#{MINIMUM_SHAKAPACKER_MAJOR_VERSION}.#{MINIMUM_SHAKAPACKER_MINOR_VERSION}.#{MINIMUM_SHAKAPACKER_PATCH_VERSION}"
    end

    def prepend_to_file_if_not_present(file, text_to_prepend)
      file_content = File.read(file)

      return if file_content.include?(text_to_prepend)

      content_with_prepended_text = text_to_prepend + file_content
      File.write(file, content_with_prepended_text)
    end
  end
  # rubocop:enable Metrics/ClassLength
end