+ # need to start the transaction here, so that the database can
+ # provide repeatable reads for the used-by checks. this means it
+ # shouldn't be possible to get race conditions.
+ Way.transaction do
+ self.lock!
+ check_consistency(self, new_way, user)
+ rel = RelationMember.find(:first, :joins => :relation,
+ :conditions => [ "visible = ? AND member_type='Way' and member_id=? ", true, self.id])
+ raise OSM::APIPreconditionFailedError.new("Way #{self.id} still used by relation #{rel.relation.id}.") if rel
+
+ self.changeset_id = new_way.changeset_id
+ self.changeset = new_way.changeset
+
+ self.tags = []
+ self.nds = []
+ self.visible = false
+ save_with_history!
+ end
+ end
+
+ # Temporary method to match interface to nodes
+ def tags_as_hash
+ return self.tags
+ end
+
+ ##
+ # if any referenced nodes are placeholder IDs (i.e: are negative) then
+ # this calling this method will fix them using the map from placeholders
+ # to IDs +id_map+.
+ def fix_placeholders!(id_map, placeholder_id = nil)
+ self.nds.map! do |node_id|
+ if node_id < 0
+ new_id = id_map[:node][node_id]
+ raise OSM::APIBadUserInput.new("Placeholder node not found for reference #{node_id} in way #{self.id.nil? ? placeholder_id : self.id}") if new_id.nil?
+ new_id
+ else
+ node_id
+ end
+ end
+ end
+
+ private
+
+ def save_with_history!
+ t = Time.now.getutc
+
+ # update the bounding box, note that this has to be done both before
+ # and after the save, so that nodes from both versions are included in the
+ # bbox. we use a copy of the changeset so that it isn't reloaded
+ # later in the save.
+ cs = self.changeset
+ cs.update_bbox!(bbox) unless nodes.empty?
+
+ Way.transaction do
+ self.version += 1
+ self.timestamp = t
+ self.save!
+
+ tags = self.tags
+ WayTag.delete_all(['id = ?', self.id])
+ tags.each do |k,v|
+ tag = WayTag.new
+ tag.k = k
+ tag.v = v
+ tag.id = self.id
+ tag.save!
+ end
+
+ nds = self.nds
+ WayNode.delete_all(['id = ?', self.id])
+ sequence = 1
+ nds.each do |n|
+ nd = WayNode.new
+ nd.id = [self.id, sequence]
+ nd.node_id = n
+ nd.save!
+ sequence += 1
+ end
+
+ old_way = OldWay.from_way(self)
+ old_way.timestamp = t
+ old_way.save_with_dependencies!
+
+ # reload the way so that the nodes array points to the correct
+ # new set of nodes.
+ self.reload
+
+ # update and commit the bounding box, now that way nodes
+ # have been updated and we're in a transaction.
+ cs.update_bbox!(bbox) unless nodes.empty?
+
+ # tell the changeset we updated one element only
+ cs.add_changes! 1
+
+ cs.save!
+ end