# Author::    Nicolas Pouillard  <ertai@lrde.epita.fr>.
# Copyright:: Copyright (c) 2004, 2005 TTK team. All rights reserved.
# License::   LGPL
# $Id: Yaml.rb 571 2005-04-13 14:41:22Z polrop $


class Symbol # :nodoc:
  alias_method :old_to_yaml, :to_yaml
  def to_yaml ( opts={} )
    # FIXME
    # if opts[:ttk]
      self.to_s.to_yaml(opts)
    # else
      # old_to_yaml(opts)
    # end
  end
end

class Class # :nodoc:
  alias_method :old_to_yaml, :to_yaml
  def to_yaml ( opts={} )
    self.to_s.sub(/^TTK::Strategies::/, '').to_yaml(opts)
  end
end

class Regexp # :nodoc:
  alias_method :old_to_yaml_type, :to_yaml_type
  alias_method :old_to_yaml, :to_yaml
  def to_yaml_type
    '!re'
  end
  def to_yaml ( opts={} )
    "#{to_yaml_type} #{source}"
  end
end

YAML.add_builtin_type('!re') do |type, val|
  Regexp.new(val.to_s)
end

class Pathname # :nodoc:
  alias_method :old_to_yaml, :to_yaml
  def to_yaml ( opts={} )
    if opts[:ttk]
      self.to_s.to_yaml(opts)
    else
      old_to_yaml(opts)
    end
  end
end

YAML.add_builtin_type('!path') do |type, val|
  Pathname.new(val.to_s)
end

class OHash # :nodoc:
  def to_yaml ( opts={} )
    if opts[:ttk]
      YAML::quick_emit(self.object_id, opts) do |out|
        out.seq('') do |seq|
          self.each do |k,v|
            seq.add( { k => v } )
          end
        end
      end
    else
      super
    end
  end
end


module TTK

  module Dumpers

    class Yaml < Dumper
      include Concrete

      MAP_SHIFT_WIDTH = 2
      SEQ_SHIFT_WIDTH = 4

      def initialize ( *a, &b )
        super
	@indent = ''
        @stack_indent = []
	@endl = true
	@flushable = @io.respond_to?(:flush)
        @io.puts '---'
        @opts = {:ttk => true}
      end


      def new_node ( path )
        super
        type = (path.nil? or path.size < 2)? :map : path[-2].last
        node = path.last.first
        @io.puts unless @endl
        @stack_indent << @indent.size
        case type
        when :map
          val = "#{clean_to_yaml(node)}:"
          @io << @indent << val
          @indent += ' ' * MAP_SHIFT_WIDTH
        when :seq
          val = "- #{clean_to_yaml(node)}:"
          @io << @indent << val
          @indent += ' ' * SEQ_SHIFT_WIDTH
        end
        @endl = false
      end
      protected :new_node


      def new_leaf ( path, node )
        super
        val = node
        if val.is_a?(String) and val =~ /\n/
          val = "|\n#{val}"
          val.chomp!
        else
          return if val.respond_to?(:hidden)
          val = clean_to_yaml(val)
        end
        val.gsub!(/\s*\n/, "\n#@indent")
        @io.print ' ', val, "\n"
        @endl = true
      end
      protected :new_leaf


      def up ( path )
        super
        @indent = ' ' * @stack_indent.pop
      end
      protected :up


      def clean_to_yaml ( val )
        val = val.to_yaml(@opts)
        val.sub!(/^--- /, '')
        val.gsub!(/(^\s*)- \n\s+([^\s-])/, '\1- \2')
        val = '""' if val == "''"
        val
      end
      private :clean_to_yaml


      def update ( *a, &b )
        super
        @io.flush if @flushable and (not @io.closed?)
      end

    end # class Yaml

  end # module Dumpers

end # module TTK