require 'erb'

module J1
  module Commands
    class Generate < Command
      class << self
        def init_with_program(prog)

          prog.command(:generate) do |c|
            c.syntax 'generate PATH'
            c.description 'Generates a starter site scaffold in PATH'
            c.option 'force', '--force', 'Force a site to be created even the PATH already exists'
            c.option 'skip-bundle', '--skip-bundle', "Skip 'bundle install'"

            c.action do |args, options|
              J1::Commands::Generate.process(args, options)
            end
          end

        end

        def process(args, options = {})
          raise ArgumentError, 'You must specify a path.' if args.empty?
          new_blog_path = File.expand_path(args.join(' '), Dir.pwd)
          FileUtils.mkdir_p new_blog_path
          if preserve_source_location?(new_blog_path, options)
            J1.logger.abort_with 'Conflict:', "#{new_blog_path} exists and is not empty."
          end

          if options['blank']
            create_blank_site new_blog_path
          else
            create_site new_blog_path
          end

          after_install(new_blog_path, options)
        end

        def create_blank_site(path)
          Dir.chdir(path) do
            FileUtils.mkdir(%w(_layouts posts/public/featured/_posts _drafts))
            FileUtils.touch('index.html')
          end
        end

        def scaffold_post_content
          ERB.new(File.read(File.expand_path(scaffold_path, starter_web))).result
        end

        # Internal: Gets the filename of the sample post to be created
        #
        # Returns the filename of the sample post, as a String
        def initialized_post_name
          "collections/posts/public/featured/_posts/#{Time.now.strftime("%Y-%m-%d")}-welcome-to-j1-template.adoc"
        end

        private

        def gemfile_contents
          <<-RUBY
          source "https://rubygems.org"
          #ruby RUBY_VERSION

          # Hello! This is where you manage which Jekyll version is used to run.
          # When you want to use a different version, change it below, save the
          # file and run `bundle install`. Run Jekyll with `bundle exec`, like so:
          #
          #     bundle exec jekyll serve
          #
          # This will help ensure the proper Jekyll version is running.
          # Happy Jekylling!
          # jadams
          #gem "jekyll", "#{Jekyll::VERSION}"
          gem "jekyll", "~> 3.8"

          # This is the default theme for generate Jekyll sites. You may change this to anything you like.
          gem "minima", "~> 2.0"

          # If you want to use GitHub Pages, remove the "gem "jekyll"" above and
          # uncomment the line below. To upgrade, run `bundle update github-pages`.
          # gem "github-pages", group: :jekyll_plugins

          # If you have any plugins, put them here!
          group :jekyll_plugins do
             gem "jekyll-feed", "~> 0.6"
          end

          # Windows does not include zoneinfo files, so bundle the tzinfo-data gem
          gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]

          RUBY
        end

        def create_site(new_blog_path)
          create_sample_files new_blog_path

          File.open(File.expand_path(initialized_post_name, new_blog_path), 'w') do |f|
            f.write(scaffold_post_content)
          end

 # jadams
 #         File.open(File.expand_path("Gemfile", new_blog_path), "w") do |f|
 #           f.write(gemfile_contents)
 #         end
        end

        def preserve_source_location?(path, options)
          !options['force'] && !Dir["#{path}/**/*"].empty?
        end

        def create_sample_files(path)
          FileUtils.cp_r starter_web + '/.', path
          FileUtils.rm File.expand_path(scaffold_path, path)
        end

        def starter_web
          File.expand_path('../../starter_web', File.dirname(__FILE__))
        end

        def scaffold_path
          'collections/posts/public/featured/_posts/0000-00-00-welcome-to-j1-template.adoc.erb'
        end

        # After a generate blog has been created, print a success notification and
        # then automatically execute bundle install from within the generate blog dir
        # unless the user opts to generate a blank blog or skip 'bundle install'.

        def after_install(path, options = {})
          unless options['skip-bundle']
            bundle_install path
          end
          unless options['force']
            J1.logger.info "Generated Jekyll site installed in folder #{path}"
          else
            J1.logger.info "Generated Jekyll site force installed in folder #{path}"
          end
          J1.logger.info 'Installation of RubyGems (bundle) skipped' if options['skip-bundle']
        end

        def bundle_install(path)
          J1::External.require_with_graceful_fail 'bundler'
          J1.logger.info "Running bundle install in #{path} ..."
          Dir.chdir(path) do
            process, output = J1::Utils::Exec.run('bundle', 'install')
            output.to_s.each_line do |line|
              J1.logger.info('Bundler:', line.strip) unless line.to_s.empty?
            end
            raise SystemExit unless process.success?
          end
        end
      end
    end
  end
end