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# Redmine - project management software
# Copyright (C) 2006-2015 Jean-Philippe Lang
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
module Redmine
module NestedSet
module Traversing
def self.included(base)
base.class_eval do
scope :roots, lambda {where :parent_id => nil}
scope :leaves, lambda {where "#{table_name}.rgt - #{table_name}.lft = ?", 1}
end
end
# Returns true if the element has no parent
def root?
parent_id.nil?
end
# Returns true if the element has a parent
def child?
!root?
end
# Returns true if the element has no children
def leaf?
new_record? || (rgt - lft == 1)
end
# Returns the root element (ancestor with no parent)
def root
self_and_ancestors.first
end
# Returns the children
def children
if id.nil?
nested_set_scope.none
else
self.class.order(:lft).where(:parent_id => id)
end
end
# Returns the descendants that have no children
def leaves
descendants.where("#{self.class.table_name}.rgt - #{self.class.table_name}.lft = ?", 1)
end
# Returns the siblings
def siblings
nested_set_scope.where(:parent_id => parent_id).where("id <> ?", id)
end
# Returns the ancestors
def ancestors
if root?
nested_set_scope.none
else
nested_set_scope.where("#{self.class.table_name}.lft < ? AND #{self.class.table_name}.rgt > ?", lft, rgt)
end
end
# Returns the element and its ancestors
def self_and_ancestors
nested_set_scope.where("#{self.class.table_name}.lft <= ? AND #{self.class.table_name}.rgt >= ?", lft, rgt)
end
# Returns true if the element is an ancestor of other
def is_ancestor_of?(other)
same_nested_set_scope?(other) && other.lft > lft && other.rgt < rgt
end
# Returns true if the element equals other or is an ancestor of other
def is_or_is_ancestor_of?(other)
other == self || is_ancestor_of?(other)
end
# Returns the descendants
def descendants
if leaf?
nested_set_scope.none
else
nested_set_scope.where("#{self.class.table_name}.lft > ? AND #{self.class.table_name}.rgt < ?", lft, rgt)
end
end
# Returns the element and its descendants
def self_and_descendants
nested_set_scope.where("#{self.class.table_name}.lft >= ? AND #{self.class.table_name}.rgt <= ?", lft, rgt)
end
# Returns true if the element is a descendant of other
def is_descendant_of?(other)
same_nested_set_scope?(other) && other.lft < lft && other.rgt > rgt
end
# Returns true if the element equals other or is a descendant of other
def is_or_is_descendant_of?(other)
other == self || is_descendant_of?(other)
end
# Returns the ancestors, the element and its descendants
def hierarchy
nested_set_scope.where(
"#{self.class.table_name}.lft >= :lft AND #{self.class.table_name}.rgt <= :rgt" +
" OR #{self.class.table_name}.lft < :lft AND #{self.class.table_name}.rgt > :rgt",
{:lft => lft, :rgt => rgt})
end
end
end
end
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