# Author::    Nicolas Pouillard  <ertai@lrde.epita.fr>.
# Copyright:: Copyright (c) 2004, 2005 TTK team. All rights reserved.
# License::   LGPL
# $Id: Loader.rb 575 2005-04-14 10:22:30Z polrop $


module TTK

  # TTK::Loaders are design to help you to make tests.
  #
  # The `testify' method is here to provide a usefull way
  # to convert anything to a test.
  #
  # For example Hash#testify instanciate a test from a hash:
  #
  #   doc = {
  #     :strategy => Cmd,
  #     :command  => 'echo -n foo',
  #     :output   => 'foo',
  #     :symtbl   => SYMTBL
  #   }
  #
  #   test = doc.testify
  #   test.run
  #
  # You can also load a test from a string, an io or a file.
  # In this case the format can change (YAML, XML...).
  # To manage this you can use TTK::Loaders to add new loader easily.
  #
  # To implement a loader you just need to subclass the abstract
  # loader (TTK::Loaders::Loader), and implement the `load_doc'
  # method.
  #
  # The `load_doc' method take an IO as argument and return
  # something which can be testified.
  module Loaders

    def self.get_class ( aClassName )
      return aClassName if aClassName.is_a? Class
      aClassName = "TTK::Strategies::#{aClassName}" unless aClassName =~ /::/
      return eval(aClassName) if aClassName =~ /[\w:]+/
      raise NameError, "not a valid class name #{aClassName}"
    end

    # FIXME: document me
    class Loader
      include Abstract

      # override me in subclasses
      def load_doc(io)
	io
      end

      def load ( anObject, &block )
        anObject.testify(self, &block)
      end

    end # class Loader

  end # module Loaders

end # module TTK



class Pathname

  def testify ( aLoader, &block )
    strategy = open { |f| f.testify(aLoader, &block) }
    strategy.symtbl[:pwd] = self.expand_path.dirname
    strategy
  end

end



class IO

  def testify ( aLoader, &block )
    aLoader.load_doc(self).testify(aLoader, &block)
  end

end



class Class

  def testify ( aLoader, &block )
    unless self < TTK::Strategies::Strategy
      raise ArgumentError, "Need a subclass of Strategy not #{name}"
    end
    new(&block)
  end

end



class Hash

  def testify ( aLoader=nil, &block )

    if size == 1 and (tab = to_a[0])[1].is_a? Hash
      name, doc = tab
      doc[:name] = name
      return doc.testify(aLoader, &block)
    end

    unless has_key? :strategy
      raise ArgumentError, "no strategy for this test (#{inspect})"
    end

    TTK::Loaders.get_class(self[:strategy]).new do |t|
      block[t] if block_given?
      t.assign(self)
    end

  end

end