# frozen_string_literal: true

module Jekyll
  # Jekyll multilingual support
  #
  # * Posts are put under _LANGUAGE/ directories
  # * The first language on the config is default
  # * Translation strings are store in _data/LANGUAGE.yml
  # * The plugin generates a copy of the site for every language at
  #   _site/LANGUAGE
  class Site
    # We don't monkey patch because the Site is already instantiated
    alias process_single process

    # Process the site once per available locale
    def process
      locales.each do |locale|
        Jekyll.logger.info 'Generating locale:', locale

        config_for locale

        Jekyll.logger.info 'Destination:', config['destination']
        Jekyll.logger.info 'Base URL:', config['baseurl']

        symlink_for locale
        process_single
        copy_redirector
      end

      default_delete
      default_symlink
    end

    private

    def config_for(locale)
      @dest = config['destination'] = destination_for(locale)
      config['baseurl'] = baseurl_for(locale)

      # XXX: Retrocompatibility
      config['locale'] = config['lang'] = locale
      config['default_locale'] = default_locale
    end

    # Get locales from configuration
    def locales
      @locales ||= config.fetch('locales', [])
    end

    def default_locale
      locales.first
    end

    # Cache original destination
    def root_destination
      @root_destination ||= config['destination']
    end

    def orig_baseurl
      @orig_baseurl ||= config.dig('baseurl') || ''
    end

    # Add locale to the site destination
    def destination_for(locale)
      File.join(root_destination, locale)
    end

    # If the site has a baseurl, we add the locale to it.  But we add
    # it anyway so relative URLs include the locale
    def baseurl_for(locale)
      [orig_baseurl, locale].join('/')
    end

    # Creates a symlink to the _posts/ directory so Jekyll believes
    # it's processing a single site.
    def symlink_for(locale)
      FileUtils.rm_f('_posts')
      FileUtils.ln_s("_#{locale}", '_posts')
    end

    # TODO: Make configurable
    def redirector
      @redirector ||= File.join(destination_for(default_locale),
                                'redirector.html')
    end

    def redirector_to_index(redir)
      File.join(root_destination,
                File.basename(redir
                    .sub('redirector', 'index')))
    end

    def copy_redirector
      return unless File.exist? redirector

      Dir.glob("#{redirector}*").each do |redir|
        FileUtils.cp(redir, redirector_to_index(redir))
      end
    end

    def default_delete
      FileUtils.rm_f default_destination
    end

    def default_destination
      @default_destination ||= File.join(root_destination, 'default')
    end

    def default_symlink
      FileUtils.ln_s(default_locale, default_destination)
    end
  end
end