class Thor

def self.[](task)
  namespaces = task.split(":")
  klass = Thor::Util.constant_from_thor_path(namespaces[0...-1].join(":"))
  raise Error, "`#{klass}' is not a Thor class" unless klass <= Thor
  klass.tasks[namespaces.last]
end

def self.convert_task_options(opts)
  opts.map do |key, value|
    case value
    when true
      "--#{key}"
    when Array
      value.map {|v| "--#{key} #{v.inspect}"}.join(" ")
    when nil, false
      ""
    else
      "--#{key} #{value.inspect}"
    end
  end.join(" ")    
end  

def self.desc(usage, description)
  @usage, @desc = usage, description
end

def self.group(name)
  @group_name = name.to_s
end

def self.group_name
  @group_name || 'standard'
end

def self.install_task(spec)
  package_task spec
  null, sudo, gem = RUBY_PLATFORM =~ /w(in)?32$/ ? ['NUL', '', 'gem.bat'] :
                                                   ['/dev/null', 'sudo', 'gem']
  
  desc "install", "install the gem"
  define_method :install do
    old_stderr, $stderr = $stderr.dup, File.open(null, "w")
    package
    $stderr = old_stderr
    system %{#{sudo} #{gem} install pkg/#{spec.name}-#{spec.version} --no-rdoc --no-ri --no-update-sources}
  end
end

def self.map(map)
  @map ||= superclass.instance_variable_get("@map") || {}
  map.each do |key, value|
    if key.respond_to?(:each)
      key.each {|subkey| @map[subkey] = value}
    else
      @map[key] = value
    end
  end
end

def self.maxima
  @maxima ||= begin
    max_usage = tasks.map {|_, t| t.usage}.max {|x,y| x.to_s.size <=> y.to_s.size}.size
    max_desc  = tasks.map {|_, t| t.description}.max {|x,y| x.to_s.size <=> y.to_s.size}.size
    max_opts  = tasks.map {|_, t| t.opts ? t.opts.formatted_usage : ""}.max {|x,y| x.to_s.size <=> y.to_s.size}.size
    Struct.new(:description, :usage, :opt).new(max_desc, max_usage, max_opts)
  end
end

def self.method_options(opts)
  @method_options = opts
end

def self.opts
  (@opts || {}).merge(self == Thor ? {} : superclass.opts)
end

def self.package_task(spec)
  desc "package", "package up the gem"
  define_method :package do
    FileUtils.mkdir_p(File.join(Dir.pwd, "pkg"))
    Gem::Builder.new(spec).build
    FileUtils.mv(spec.file_name, File.join(Dir.pwd, "pkg", spec.file_name))
  end
end

def self.spec_task(file_list, opts = {})
  name = opts.delete(:name) || "spec"
  rcov_dir = opts.delete(:rcov_dir) || "coverage"
  file_list = file_list.map {|f| %["#{f}"]}.join(" ")
  verbose = opts.delete(:verbose)
  opts = {:format => "specdoc", :color => true}.merge(opts)
  
  rcov_opts = convert_task_options(opts.delete(:rcov) || {})
  rcov = !rcov_opts.empty?
  options = convert_task_options(opts)
  
  if rcov
    FileUtils.rm_rf(File.join(Dir.pwd, rcov_dir))
  end
  
  desc(name, "spec task")
  define_method(name) do
    cmd = "ruby "
    if rcov
      cmd << "-S rcov -o #{rcov_dir} #{rcov_opts} "
    end
    cmd << `which spec`.chomp
    cmd << " -- " if rcov
    cmd << " "
    cmd << file_list
    cmd << " "
    cmd << options
    puts cmd if verbose
    system(cmd)
    exit($?.exitstatus)
  end
end

def self.start(args = ARGV)
  options = Thor::Options.new(self.opts)
  opts = options.parse(args, false)
  args = options.trailing_non_opts
  meth = args.first
  meth = @map[meth].to_s if @map && @map[meth]
  meth ||= "help"
  
  tasks[meth].parse new(opts, *args), args[1..-1]
rescue Thor::Error => e
  $stderr.puts e.message
end

def self.subclass_files
  @subclass_files ||= Hash.new {|h,k| h[k] = []}
end

def self.subclasses
  @subclasses ||= []
end

def self.tasks
  @tasks ||= TaskHash.new(self)
end

def help(task = nil)
  if task
    if task.include? ?:
      task = self.class[task]
      namespace = true
    else
      task = self.class.tasks[task]
    end
    puts task.formatted_usage(namespace)
    puts task.description
  else
    puts "Options"
    puts "-------"
    self.class.tasks.each do |_, task|
      format = "%-" + (self.class.maxima.usage + self.class.maxima.opt + 4).to_s + "s"
      print format % ("#{task.formatted_usage}")      
      puts  task.description.split("\n").first
    end
  end
end

def inherited(klass)
  register_klass_file klass
end

def initialize(opts = {}, *args)
end

def method_added(meth)
  meth = meth.to_s
  
  if meth == "initialize"
    @opts = @method_options
    @method_options = nil
    return
  end
  return if !public_instance_methods.include?(meth) || !@usage
  register_klass_file self
  tasks[meth] = Task.new(meth, @desc, @usage, @method_options)
  @usage, @desc, @method_options = nil
end

def register_klass_file(klass, file = caller[1].split(":")[0])
  unless self == Thor
    superclass.register_klass_file(klass, file)
    return
  end
  file_subclasses = subclass_files[File.expand_path(file)]
  file_subclasses << klass unless file_subclasses.include?(klass)
  subclasses << klass unless subclasses.include?(klass)
end