require 'rbconfig'
require 'fileutils'

require 'facet/fileutils/safe_ln'
require 'facet/string/tabto'
require 'facet/module/basename'
require 'facet/module/attr_setter'

require 'facet/filelist'


# Base class for reap tasks.
#
# Here's an oh so simple example:
#
#   class MyTask < Reap::Task
#
#     register 'mytask'
#
#     default_desc 'this is a custom reap task'
#
#     attr_accessor :message
#
#     def init
#       @message ||= master['default'] || 'None Found!'
#     end
#
#     def run
#       puts @message
#     end
#   end
#
# The corresponding settings in the ProjectInfo file will then be:
#
#   default: Default text, if any.
#
#   myname:
#     TASK: mytask
#     message: Message text, if any.
#
module Reap

  @registry ||= {}

  # Hash of all task classes
  def self.registry ; @registry ; end

  # Hash of tasks available to this project
  def self.tasks
    unless @tasks
      @tasks = {}
      @registry.each { |name, klass|
        @tasks[name] = klass if klass.verify?
      }
    end
    @tasks
  end

  def self.register
    $PROJECT_INFO = ProjectInfo.new( $PROJECT_FILE )

    #@registry ||= {}
    #ObjectSpace.each_object(Class) { |klass|
    #  if klass < ::Reap::Task
    #    if klass.verify
    #      @registry[klass.basename.downcase] = klass
    #    end
    #  end
    #}
  end

#   def self.initialize
#     @tasks ||= {}
#     registry.each do |name, klass|
#       @tasks[name] = klass.new
#     end
#   end


  class Task

    include ::Config
    include ::FileUtils

    RUBY = CONFIG['ruby_install_name']

    class << self

      def task_desc( text=nil, &block )
        if text
          @task_desc = proc { text }
        elsif block_given?
          @task_desc = block
        else
          @task_desc.call
        end
      end

      def task_help( text=nil, &block )
        if text
          @task_help = proc { text }
        elsif block_given?
          @task_help = block
        else
          @task_help.call
        end
      end

      #def task_desc ; '(no desciption given)' ; end
      def task_name ; basename.downcase ; end

      def section_required( val ) ; @section_required = val ;end
      def section_required?       ; @section_required ; end

      def verify?
        if section_required?
          return $PROJECT_INFO.info.key?(task_name)
        end
        true
      end

      def inherited( base )
        Reap.registry[base.task_name] = base
      end

      def master_attributes ; @master_attributes ||= [] ; end

      # Use this DSL method to define master task attributes.
      def attr_master( *names )
        attr_accessor *names
        @master_attributes ||= []
        @master_attributes |= names.collect { |n| n.to_s }
      end

    end

    # instance methods

    def task_name ; self.class.task_name ; end
    def task_desc ; self.class.task_desc ; end

    def section_required? ; self.class.section_required? ; end

    #def master ; ::ProjectInfo.info ; end
    def master ; @master ; end
    def section ; @section ; end

    #
    def initialize( *args )
      @master = $PROJECT_INFO

      sect = @master[task_name]
      if sect.is_a?(Array)
        @master[task_name].each do |sec|
          set( sec )
          init
          run
        end
      else
        set( sect || {} )
        init
        run
      end
    end

    def set( sec )
      @section = sec

      self.class.master_attributes.each do |k,v|
        send( "#{k}=", @master[k] )
      end

      @section.each do |k,v|
        send( "#{k}=", v )
      end
    end

    def init
      raise "not implemented for '#{task_name}' task"
    end

    def run
      raise "no action defined for task #{task_name}"
    end

    # task support methods

    def sh( arg )
      puts arg
      system arg unless $PRETEND
    end

  end #class Task

end #module Reap


##
# Convenience methods for built-in rake tasks
##
# module RakeTask
#   extend self
#
#   def gem_package_task(*args,&blk)
#     ::Rake::GemPackageTask.new(*args,&blk)
#   end
#
#   def package_task(*args,&blk)
#     ::Rake::PackageTask.new(*args,&blk)
#   end
#
#   def test_task(*args,&blk)
#     ::Rake::TestTask.new(*args,&blk)
#   end
#
#   def rdoc_task(*args,&blk)
#     ::Rake::RDocTask.new(*args,&blk)
#   end
#
# end