/**
* Add a node to the tree.
*
* @param DecisionTree_Node $node
*/
function addNode(DecisionTree_Node $node)
{
$id = $node->getId();
if (isset($this->nodes[$id])) {
throw new Exception("Node with id " . $node->id() . " is already part of the tree.");
}
$node->_bind($this);
$this->nodes[$id] = $node;
}
/**
* Set the transition to the next node.
* Note: To decide the next node, the transitions will be checked in the reverse order they were set.
*
* @param DecisionTree_Node|mixed $node Next node or id of next node
* @param array $conditions Set with conditiona which needs to be true to do this transition
*/
function setTransition($node, $conditions = null)
{
if (!isset($this->_index)) {
$this->_index = DecisionTree_Index();
}
if (!is_array($conditions)) {
$conditions = empty($conditions) ? array() : array($conditions);
}
foreach ($conditions as $key => $condition) {
if ($condition instanceof DecisionTree_Condition) {
continue;
}
unset($conditions[$key]);
$condition = $this->_index->loadCondition($condition);
if (is_array($condition)) {
$conditions = array_merge($conditions, $condition);
} else {
$conditions[$key] = $condition;
}
}
$transition = (object) array('node' => $node, 'conditions' => $conditions);
if (empty($conditions)) {
if (isset($this->_transitions[0])) {
throw new Exception("Unable to create transition from node '" . $this->id() . "' to node '" . ($node instanceof self ? $node->id() : $node) . ". A default transition already exists.");
}
array_unshift($this->_transitions, $transition);
} else {
$transkey = reset($conditions)->id();
if (isset($this->_transitions[$transkey])) {
throw new Exception("Unable to create transition from node '" . $this->id() . "' to node '" . ($node instanceof self ? $node->id() : $node) . ". A transition for condition '{$transkey}' already exists.");
}
$this->_transitions[$transkey] = $transition;
}
if (is_object($node) && $node instanceof self) {
if ($node->index() === null) {
$this->_index->addNode($node);
} elseif ($this->_index != $node->index()) {
$this->_index->merge($node->index());
}
}
}
