require 'chunks/wiki'
require 'date'
require 'parsedate'

# ToDo items.
class Todo < Chunk::Abstract
  def self.pattern() /todo(@[\w,]+)?: (.*?)(?=<br|\r|\n|\z)/i end

  attr_accessor :context, :due_date

  def initialize(match_data, revision)
    super(match_data, revision)
    @context = match_data[1]
    @context = @context.nil? || @context.empty? ? [] : @context.delete('@').split(',')
    @text = match_data[2]
    begin
      d = ParseDate.parsedate(@text)
      # see if there's a date in the todo:
      if not d.all? { |x| x.nil? }
        d = d[0..2]
        # sanity check the order retured from ParseDate: stuff like 'Jan 2005' 
        # will be returned in inverse order to '12 Jan 2005'. (ie. no automatic bounds checking)
        d.reverse! if d[2] > 31
        # get the [year,month,date] with sane values if you miss the day/year.
        # this should allow users to specify stuff like 'Dec 2005' or 'Dec 21'.
        d = [ d[0] || Date.today.year, d[1], d[2] || 1 ]
        @due_date = Date.new(*d)
      end
    rescue => detail
      @due_date = nil
    end
  end

  def escaped_text() nil end

  def unmask(content) 
    return self if content.gsub!( Regexp.new(mask(content)),
      # the style 'todo' is bright-red to be eye catching. It is not expected that
      # there will be too many items on one page, but each is supposed to stand out.
      # The ToDo special page differentiates between the 'todo' and 'todoFuture' styles.
      "<todo-tag context='#{@context.join(',')}' due_date='#{@due_date}'><span class=\"todo\"><strong>TODO#{ " @ #{@context.join(', ')}" unless @context.empty?}:</strong> #{@text}</span></todo-tag>" )
  end
end