require 'middleman-core/cli'
require 'active_support/core_ext/time/zones'

module Middleman
  module Cli
    # This class provides a "tansu" command for middleman CLI.
    #
    # "tansu" command has some options:
    # - '-f': set file extension, default "md"
    # - '-d': set date(yyyy-mm-dd). Default is now. This is used in Frontmatter.
    # - '-a': set author name. Default "ENV['USER']".
    # - '-z': set timezone.
    # - '--frontmatter': add data to Frontmatter
    class Tansu < Thor
      include Thor::Actions

      check_unknown_options!

      namespace :tansu

      def initialize(*args)
        super
        Time.zone = ENV['TZ'] || 'UTC'
      end

      def self.source_root
        ENV['MM_ROOT']
      end

      # Tell Thor to exit with a nonzero exit code on failure
      def self.exit_on_failure?
        true
      end

      desc 'tansu path/to/TITLE', 'Create a new Tansu page'
      method_option 'file',
        aliases: '-f',
        desc: 'The file extension of file (default: md)',
        default: 'md'
      method_option 'timezone',
        aliases: '-z',
        desc: 'The timezone of Frontmatter (default: ENV["TZ"])'
      method_option 'date',
        aliases: '-d',
        desc: 'The date of Frontmatter (default: Time.zone.now)',
        default: nil
      method_option 'author',
        aliases: '-a',
        desc: 'The author name of Frontmatter (default: ENV["USER"])'
      method_option 'current',
        type: :boolean,
        aliases: '-c',
        default: false,
        desc: 'Create file from current direcotry'
      method_option 'frontmatter',
        desc: 'Additions of Frontmatter ex:"category:sample,tags:frontmatter"',
        default: ''
      def tansu(path)
        paths     = path.split('/')
        title     = paths.pop
        ext       = options[:file]
        Time.zone = options[:timezone] || ENV['TZ'] || 'UTC'
        date      = options[:date] ? Time.zone.parse(options[:date]) : Time.zone.now
        author    = options[:author] || ENV['USER']
        add_frontmatter = options[:frontmatter]

        if Regexp.new(".html.#{ext}$") !~ title
          filename = "#{title}.html.#{ext}"
        end

        if options[:current]
          file = File.join(filename)
        else
          dir  = destination_dir(paths)
          file = File.join(dir, filename)
          FileUtils.mkdir_p dir unless Dir.exist?(dir)
        end

        if File.exist?(file)
          say "#{display_path(file)} is exist"
          exit
        end

        File.open(file, 'w') do |f|
          f.puts frontmatter(title, author, date, add_frontmatter)
        end
        say "create tansu page: #{display_path(file)}"
      end

      no_tasks do
        def frontmatter(title, author, date, frontmatter)
          data = {
            title: title,
            author: author,
            date: date
          }

          unless frontmatter.empty?
            data = data.merge(add_frontmatter(frontmatter))
          end

          rows = ['---']
          data.each do |label, val|
            rows << "#{label}: #{val.to_s.strip}"
          end
          rows << ['---']
          rows << "\n\n"

          rows.join("\n")
        end

        def add_frontmatter(str)
          {} if str.empty?
          frontmatter = {}
          str.split(',').each do |row|
            if /.+:.+/ =~ row
              _, label, data = row.split(/(.+?):(.+)$/)
              frontmatter[label] = data
            else
              frontmatter[row] = ''
            end
          end
          frontmatter
        end

        def destination_dir(dir)
          if dir.nil? || dir == '.'
            source
          else
            File.join(source, dir)
          end
        end

        def source
          app = Middleman::Application
          File.join(app.root, app.config.source)
        end

        def display_path(path)
          path.sub(Regexp.new("^#{source}/"), '')
        end
      end
    end
  end
end