require "appbundler/version"
require "appbundler/app"
require "mixlib/cli"

module Appbundler
  class CLI
    include Mixlib::CLI

    banner(<<-BANNER)
* appbundler #{VERSION} *

Usage: appbundler BUNDLE_DIR BINSTUB_DIR [GEM_NAME] [GEM_NAME] ...

  BUNDLE_DIR is the root directory to the bundle containing your app
  BINSTUB_DIR is the directory where you want generated executables to be written
  GEM_NAME is the name of a gem you want to appbundle. Default is the directory name
           of BUNDLE_DIR (e.g. /src/chef -> chef)

Your bundled application must already be gem installed.  Generated binstubs
will point to the gem, not your working copy.
BANNER

    # this is used by chef-dk, its probably not an external API, here be dragons
    option :without,
      :long => "--without GROUPS",
      :description => "Comma separated list of groups to exclude when building transitive Gemfile.locks (internal API)",
      :proc => lambda { |o| o.split(/[\s,]+/) },
      :default => []

    option :extra_bin_files,
      :long => "--extra-bin-files bin1,bin2",
      :description => "Comma separated list of extra binstubs to wire up which are not listed in the gemspec",
      :proc => lambda { |o| o.split(/[\s,]+/) },
      :default => []

    option :version,
      :short => "-v",
      :long => "--version",
      :description => "Show appbundler version",
      :boolean => true,
      :proc => lambda { |v| $stdout.puts("Appbundler Version: #{::Appbundler::VERSION}") },
      :exit => 0

    option :help,
      :short => "-h",
      :long => "--help",
      :description => "Show this message",
      :on => :tail,
      :boolean => true,
      :show_options => true,
      :exit => 0

    def self.run(argv)
      cli = new(argv)
      cli.handle_options
      cli.validate!
      cli.run
    end

    attr_reader :argv

    attr_reader :bundle_path
    attr_reader :bin_path
    attr_reader :gems

    def initialize(argv)
      @argv = argv
      super()
    end

    def handle_options
      parse_options(@argv)
    end

    def validate!
      if cli_arguments.size < 2
        usage_and_exit!
      else
        @bundle_path = File.expand_path(cli_arguments[0])
        @bin_path = File.expand_path(cli_arguments[1])
        @gems = cli_arguments[2..-1]
        @gems = [ nil ] if @gems.empty?
        verify_bundle_path
        verify_bin_path
      end
    end

    def verify_bundle_path
      if !File.directory?(bundle_path)
        err("BUNDLE_DIR `#{bundle_path}' is not a directory or doesn't exist")
        usage_and_exit!
      elsif !File.exist?(File.join(bundle_path, "Gemfile.lock"))
        err("BUNDLE_DIR does not contain required Gemfile.lock")
        usage_and_exit!
      end
    end

    def verify_bin_path
      if !File.directory?(bin_path)
        err("BINSTUB_DIR `#{bin_path}' is not a directory or doesn't exist")
        usage_and_exit!
      end
    end

    def run
      gems.each do |g|
        app = App.new(bundle_path, bin_path, g, config[:extra_bin_files])
        created_stubs = app.write_executable_stubs
        created_stubs.each do |real_executable_path, stub_path|
          $stdout.puts "Generated binstub #{stub_path} => #{real_executable_path}"
        end
        created_lockfile = app.write_merged_lockfiles(without: config[:without])
        $stdout.puts "Generated merged lockfile at #{created_lockfile}" if created_lockfile
      end
    end

    def err(message)
      $stderr.print("#{message}\n")
    end

    def usage_and_exit!
      err(banner)
      exit 1
    end
  end
end