class MkmfTasks
  attr_writer :extconf_file_name,
              :project_dir,
              :file_extension,
              :extension_paths,
              :extconf_arguments

  def initialize(actor)
    @actor = actor
  end

  def default
    compile
  end

  def compile
    @extension_paths.each do |extension|
      dir = "ext/#{extension}"
      extconf dir
      make dir
    end
  end

  def spec
    compile
    install
    dir = @project_dir
    require File.expand_path("#{dir}/spec/spec_suite")
  end

  def lib
    directory "lib"
  end

  def install
    @extension_paths.each do |extension_path|
      build_path = build_path(extension_path)
      raise "File #{build_path} does not exist" unless File.exists?(build_path)
      cp build_path, library_path(extension_path)
    end
  end

  def cleanup
    @extension_paths.each do |extension_path|
      library_path = library_path(extension_path)
      rm library_path if library_path && File.exists?(library_path)

      build_file_path = build_path(extension_path)
      rm build_file_path if build_file_path && File.exists?(build_file_path)

      build_object_path = "#{build_path_without_file_extension(extension_path)}.o"
      rm build_object_path if build_object_path && File.exists?(build_object_path)

      build_dir = build_dir(extension_path)
      make_file_path = "#{build_dir}/Makefile"
      rm make_file_path if make_file_path && File.exists?(make_file_path)
    end    
  end

  protected
  def extconf(dir)
    Dir.chdir(dir) do
      sh("ruby #{@extconf_arguments} #{@extconf_file_name}")
    end
  end

  def make(makedir)
    Dir.chdir(makedir) do
      sh("make")
    end
  end

  def build_dir(relative_extension_path)
    "#{@project_dir}/ext/#{relative_extension_path}"
  end

  def build_path(relative_extension_path)
    basename = build_path_without_file_extension(relative_extension_path)
    "#{basename}.#{@file_extension}"
  end

  def build_path_without_file_extension(relative_extension_path)
    "#{build_dir(relative_extension_path)}/#{File.basename(relative_extension_path)}"
  end

  def library_path(relative_extension_path)
    library_directory_path = File.expand_path("#{@project_dir}/lib/#{File.dirname(relative_extension_path)}")
    binary_name = "#{File.basename(relative_extension_path)}.#{@file_extension}"
    "#{library_directory_path}/#{binary_name}"
  end

  def rm(path)
    @actor.__send__ :rm, path
  end

  def sh(cmd)
    @actor.__send__ :sh, cmd
  end
end