# * George Moschovitis  <gm@navel.gr>
# (c) 2004-2005 Navel, all rights reserved.
# $Id: tree.rb 1 2005-04-11 11:04:30Z gmosx $

# NOT WORKING YET !!!

raise 'This is not working yet, do not require this file.'

require 'glue/attribute'

module Og

# A useful encapsulation of the nested intervals pattern for 
# hierarchical SQL queries. Slightly adapted from the original
# article (http://www.dbazine.com/tropashko4.shtml)

module TreeTraversal
	
	# The default prefix for the tree traversal helpers.
	
	cattr_accessor :prefix, 'tree'	

	def self.child(sum, n)
		power = 2 ** n

		return sum * power
	end

end

end


__END__

def xcoord(numer, denom)
	num = numer + 1
	den = denom * 2

	while (num / 2).floor == (num / 2)
		num /= 2
		den /= 2
	end

	return num, den
end

#--
# TODO: optimize this
#++

def ycoord(numer, denom)
	num, den = xcoord(numer, denom)

	while den < denom
		num *= 2
		den *= 2
	end

	num = numer - num

	while (num / 2).floor == (num / 2)
		num /= 2
		den /= 2
	end

	return num, den
end

def parent(numer, denom)
	return nil if numer == 3

	num = (numer - 1) / 2
	den = denom / 2

	while ((num-1)/4).floor == ((num-1)/4)
		num = (num + 1) / 2
		den = den / 2
	end
	
	return num, den
end

def sibling(numer, denom)
	return nil if numer == 3

	num = (numer - 1) / 2
	den = denom / 2
	sib = 1
	
	while ((num-1)/4).floor == ((num-1)/4)
		return sib if num == 1 and den == 1
		num = (num + 1) / 2
		den /= 2
		sib += 1
	end
	
	return sib
end

def child(numer, denom, n)
	power = 2 ** n

	num =  (numer * power) + 3 - power
	den = denom * power

	return num, den
end

def path(numer, denom)
	return '' if numer == nil
	n, d = parent(numer, denom)
	return "#{path(n, d)}.#{sibling(numer, denom)}"
end

def encode(path)
	num = den = 1
	postfix = ".#{path}."

	while postfix.length > 1
		sibling, postfix = postfix.split('.', 2)
		num, den = child(num, den, sibling.to_i)
	end

	return num, den
end


require 'og'

class Comment
	property :path, String
	property :x, :y, Float

	def initialize(path = nil, x = nil, y = nil)
		@path, @x, @y = path, x, y
	end
end

Og::Database.new(
	:database => 'test',
	:adapter => 'psql',
	:user => 'postgres',
	:password => 'navelrulez',
	:connection_count => 1,
	:drop => true
)

def dp(path)
	n, d =  encode(path)
	n, d = Float(n), Float(d)
	# puts "#{path} -> n: #{n} d: #{d} c: #{n/d}"
	p = path(n, d)
	# puts "=== #{p}"
	xn, xd = xcoord(n, d)
	yn, yd = ycoord(n, d)
	Comment.create(path, xn/xd, yn/yd)
end

dp '1.1'
dp '1.2'
dp '1.3'
dp '1.1.2.1'
dp '1.5.2.1'
dp '1.2.1.1.1'
dp '1.4.1.1'
dp '1.4.3'
dp '1.4.1'
dp '1.2.1'
dp '1.2.1.2'
dp '1.5'
dp '1.5.1'

for c in Comment.all('ORDER BY x DESC, y ASC')
	puts "#{c.path.ljust(16)}#{c.inspect}"
end

class Article
	property :title, :body, String
	has_many: :comments, Comment, :tree => true
end

class Comment
	property :body, String
	belongs_to :article, Article
	belongs_to :parent, Comment
	has_many :children, Comment, :tree => true
	has_many :roles, Role, :list => true
end


article.comments_tree
comment.add_child(Comment.new('hello'))
comment.children_tree
comment.children

		if options[:tree]
			code << %{
				property :#{prefix}_x, Fixnum
				property :#{prefix}_y, Fixnum
				sql_index '#{prefix}_x, #{prefix}_y'
			}
		end

		if options[:tree]

			code << %{
				def #{name}_tree(extrasql = nil)
					Og.db.select("SELECT * FROM #{Og::Adapter.table(klass)} WHERE #{linkback}=\#\@oid \#\{extrasql\} ORDER BY #{prefix}_x DESC, #{prefix}_y ASC", #{klass})
				end
			}

		elsif options[:list]

		else

		end

		}
		
		if options[:tree]
			code << %{
				n = Og.db.count("#{linkback}=\#\@oid", #{klass})
				ptx = @#{prefix}_x || 0
				pty = @#{prefix}_y || 0
				obj.#{prefix}_x, obj.#{prefix}_y = TreeTraversal.child(ptx + pty, n)
			}
		end
		
		code << %{