require 'active_support/core_ext/class/attribute'

module Spring
  @commands = {}

  class << self
    attr_reader :commands
  end

  def self.register_command(name, klass, options = {})
    commands[name] = klass

    if options[:alias]
      commands[options[:alias]] = klass
    end
  end

  def self.command?(name)
    commands.include? name
  end

  def self.command(name)
    commands.fetch name
  end

  module Commands
    class Command
      class_attribute :preloads
      self.preloads = []

      def setup
        preload_files
      end

      private

      def preload_files
        preloads.each do |file|
          begin
            require file
          rescue LoadError => e
            $stderr.puts <<-MESSAGE
The #{self.class} command tried to preload #{file} but could not find it.
You can configure what to preload in your `config/spring.rb` with:
  #{self.class}.preloads = %w(files to preload)
MESSAGE
          end
        end
      end
    end

    class Test < Command
      self.preloads += %w(test_helper)

      def env
        "test"
      end

      def setup
        $LOAD_PATH.unshift "test"
        super
      end

      def call(args)
        if args.size > 0
          ARGV.replace args
          path = File.expand_path(args.first)

          if File.directory?(path)
            Dir[File.join path, "**", "*_test.rb"].each { |f| require f }
          else
            require path
          end
        else
          $stderr.puts "you need to specify what test to run: spring test TEST_NAME"
        end
      end
    end
    Spring.register_command "test", Test.new

    class RSpec < Command
      self.preloads += %w(spec_helper)

      def env
        "test"
      end

      def setup
        $LOAD_PATH.unshift "spec"
        super
        require 'rspec/core'
      end

      def call(args)
        $0 = "rspec"
        ::RSpec::Core::Runner.run(args)
      end
    end
    Spring.register_command "rspec", RSpec.new

    class Cucumber < Command
      def env
        "test"
      end

      def setup
        super
        require 'cucumber'
      end

      def call(args)
        ::Cucumber::Cli::Main.execute(args)
      end
    end
    Spring.register_command "cucumber", Cucumber.new

    class Rake < Command
      def setup
        super
        require "rake"
      end

      def call(args)
        ARGV.replace args
        ::Rake.application.run
      end
    end
    Spring.register_command "rake", Rake.new


    class Console < Command
      def call(args)
        # This cannot be preloaded as it messes up the IRB prompt on OS X
        # for unknown reasons. See discussion in issue #34.
        require "rails/commands/console"

        ARGV.replace args
        ::Rails::Console.start(::Rails.application)
      end
    end
    Spring.register_command "console", Console.new, alias: "c"

    class Generate < Command
      def setup
        super
        Rails.application.load_generators
      end

      def call(args)
        ARGV.replace args
        require "rails/commands/generate"
      end
    end
    Spring.register_command "generate", Generate.new, alias: "g"

    class Runner < Command
      def call(args)
        Object.const_set(:APP_PATH, Rails.root.join('config/application'))
        ARGV.replace args
        require "rails/commands/runner"
      end
    end
    Spring.register_command "runner", Runner.new, alias: "r"
  end

  # Load custom commands, if any.
  # needs to be at the end to allow modification of existing commands.
  config = File.expand_path("./config/spring.rb")
  require config if File.exist?(config)

end