module DocMachine
  class Launcher
    def initialize(config)
      @basedir = config[:data_dir]? ? config[:data_dir] : Dir.current
      @basehash = Digest::SHA256.hexdigest(@basedir)[0..6]
      @action = config[:action]? ? config[:action] : "watch"
      # @verbosity = config[:verbose]? ? config[:verbose] : 0
      @docker_name = "docmachine-#{@basehash}"
      @docker_image = "glenux/docmachine:latest"
      @docker_opts = [] of String
      @enable_tty = !!config[:tty]?
      @process = nil
    end


    # cleanup environment
    # create directories
    # setup permissions
    def prepare()
      puts "basedir      = #{@basedir}"
      puts "docker_image = #{@docker_image}"
      puts "action       = #{@action}"

      docker_cid = %x{docker ps -f "name=#{@docker_name}" -q}.strip

      puts "docker_name: #{@docker_name}"
      puts "docker_cid: #{docker_cid}"

      if !docker_cid.empty?
        Process.run("docker", ["kill", @docker_name])
      end
    end

    def start()
      uid = %x{id -u}.strip
      gid = %x{id -g}.strip
      puts "uid: #{uid}"
      puts "cid: #{gid}"

      docker_opts = [] of String
      docker_opts << "run"
      docker_opts << "-i"
      # add tty support
      docker_opts << "-t" if @enable_tty
      # add container name
      docker_opts.concat ["--name", @docker_name]
      docker_opts << "--rm"
      docker_opts << "--shm-size=1gb"
      docker_opts.concat ["-e", "EXT_UID=#{uid}"]
      docker_opts.concat ["-e", "EXT_GID=#{gid}"]
      docker_opts.concat ["-v", "#{@basedir}/docs:/app/docs"]
      docker_opts.concat ["-v", "#{@basedir}/slides:/app/slides"]
      docker_opts.concat ["-v", "#{@basedir}/images:/app/images"]
      docker_opts.concat ["-v", "#{@basedir}/_build:/app/_build"]

      ## Detect Marp SCSS
      if File.exists?("#{@basedir}/.marp/theme.scss")
        docker_opt_marp_theme = ["-v", "#{@basedir}/.marp:/app/.marp"]
        docker_opts.concat docker_opt_marp_theme
        puts "Theme: detected Marp files. Adding option to command line (#{docker_opt_marp_theme})"
      else
        puts "Theme: no theme detected. Using default files"
        end

      ## Detect Mkdocs configuration - old format (full)
      if File.exists?("#{@basedir}/mkdocs.yml")
        puts "Mkdocs: detected mkdocs.yml file. Please rename to mkdocs-patch.yml"
        exit 1
      end

      ## Detect Mkdocs configuration - new format (patch)
      if File.exists?("#{@basedir}/mkdocs-patch.yml")
        docker_opt_mkdocs_config = ["-v", "#{@basedir}/mkdocs-patch.yml:/app/mkdocs-patch.yml"]
        docker_opts.concat docker_opt_mkdocs_config
        puts "Mkdocs: detected mkdocs-patch.yml file. Adding option to command line (#{docker_opt_mkdocs_config})"
      else
        puts "Mkdocs: no mkdocs-patch.yml detected. Using default files"
        end

      ## Detect slides
      if Dir.exists?("#{@basedir}/slides")
        docker_opt_marp_port = ["-p", "5200:5200"]
        docker_opts.concat docker_opt_marp_port 
        puts "Slides: detected slides directory. Adding option to command line (#{docker_opt_marp_port})"
      else
        puts "Slides: no slides directory detected."
        end

      ## Detect docs
      if Dir.exists?("#{@basedir}/docs")
        docker_opt_marp_port = ["-p", "5100:5100"]
        docker_opts.concat docker_opt_marp_port
        puts "Slides: detected docs directory. Adding option to command line (#{docker_opt_marp_port})"
      else
        puts "Slides: no slides docs detected."
        end

      docker_opts << @docker_image
      docker_opts << @action

      puts docker_opts.inspect.colorize(:yellow)
      @process = Process.new("docker", docker_opts, output: STDOUT, error: STDERR)
    end

    def wait()
      process = @process
      return if process.nil?

      Signal::INT.trap do
        STDERR.puts "Received CTRL-C"
        process.signal(Signal::KILL)
        Process.run("docker", ["kill", @docker_name])
      end
      process.wait
    end

    def stop()
    end

    def docker_opts()
    end
  end
end