module FS
  module Base
    
    # FileUtils.touch
    def touch(*files)
      FileUtils.touch(files)
    end

    # FileUtils#mkdir
    def makedir(*dirs)
      FileUtils.mkdir(dirs)
    end

    # FileUtils#mkdir_p
    def makedirs(*dirs)
      FileUtils.mkdir_p(dirs)
    end

    # FileUtils#rmdir
    def removedir(*dirs)
      dirs.each do |dir|
        raise Errno::ENOTEMPTY unless list(dir).empty?
      end
      FileUtils.rmdir(dirs)
    end

    # FileUtils#rm_r
    def removedirs(*dirs)
      FileUtils.rm_r(dirs)
    end

    # Dir#glob
    def list(dir='.', pattern='*')
      glob(dir, pattern)
    end

    # Dir#glob
    # TODO: use Find#find
    def find(dir='.', pattern='*')
      glob(dir, '**', pattern)
    end

    # TODO: find time to make this cool, not work only
    # FileUtils#mv
    def move(*froms, to)
      froms.each do |from|
        FileUtils.mv(from, to)        
      end
    end

    # TODO: find time to make this cool, not work only
    # FileUtils#cp
    def copy(*froms, to)
      froms.each do |from|
        FileUtils.cp(from, to)
      end
    end
    
    # Creates hard links for files and symbolic links for dirs
    #
    # FileUtils#ln or FileUtils#ln_s
    def link(from, to)
      if File.directory?(from)
        FileUtils.ln_s(from, to)
      else
        FileUtils.ln(from, to)
      end
    end
    
    # FileUtils#rm
    def remove(*pathes)
      FileUtils.rm(pathes)
    end

    # File#open(file, 'w')
    def write(file, content=nil, &block)
      if block_given?
        File.open(file, 'w', &block)
      else
        File.open(file, 'w') {|f| f.write(content) }
      end
    end

    # File#open(file, 'r')
    def read(file, &block)
      if block_given?
        File.open(file, 'r', &block)
      else
        content = nil
        File.open(file, 'r') {|f| content = f.read }
        content
      end
    end

    # Dir#home
    def home(user=nil)
      Dir.home(user)
    end

    # always returns '/'
    def root
      '/'
    end

    # Dir#chdir
    def changedir(dir)
      Dir.chdir(dir)
    end
    
    # Dir#pwd
    def currentdir
      Dir.pwd
    end

    private
    
    def assert_dir(path)
      raise "not a directory: #{path}" unless File.directory?(path)
    end

    def glob(dir, *patterns)
      fulldir = File.expand_path(dir)
      Dir.glob(File.join(fulldir, patterns)).map do |path|
        path.gsub(/^#{fulldir}\/?/, '')
      end
    end
    
  end
end