/**
* Makes the first node the parent of the second node.
* @access public
* @param mixed parentIdValue The string id of the node to add as a parent.
* @param mixed childIdValue The string id of the child node.
* @return void
**/
function addParent($parentIdValue, $childIdValue)
{
// ** parameter validation
ArgumentValidator::validate($parentIdValue, OrValidatorRule::getRule(NonzeroLengthStringValidatorRule::getRule(), IntegerValidatorRule::getRule()), true);
ArgumentValidator::validate($childIdValue, OrValidatorRule::getRule(NonzeroLengthStringValidatorRule::getRule(), IntegerValidatorRule::getRule()), true);
// ** end of parameter validation
// get the two nodes
$parent = $this->getNode($parentIdValue);
$child = $this->getNode($childIdValue);
// the next two calls make sure everything will go smoothly
// i.e. will help to detect that $parent is not already a parent of $child
$parent->getChildren();
$child->getParents();
$this->traverse($child->getId(), true, -1);
// traverse fully down in order to detect cycles
// get the tree nodes
$parentTreeNode = $this->_tree->getNode($parentIdValue);
$childTreeNode = $this->_tree->getNode($childIdValue);
// make sure that we are not adding a second parent in a single-parent hierarchy
if (!$this->_allowsMultipleParents) {
if ($childTreeNode->getParentsCount() > 1) {
throwError(new Error(HierarchyException::SINGLE_PARENT_HIERARCHY(), "HierarchyCache", true));
}
}
// IMPORTANT SPECIAL CASES:
// A = the number of levels that the parent is cached down
$A = $this->_cache[$parentIdValue][1];
// B = the number of levels that the child is cached down
$B = $this->_cache[$childIdValue][1];
// if B < A-1 AND B >= 0 then cache down the child A-1 levels
if ($B < $A - 1 && $B >= 0) {
$this->_traverseDown($childIdValue, $A - 1);
}
// if A < 0 AND B >= 0 then cache down the child fully
if ($A < 0 && $B >= 0) {
$this->_traverseDown($childIdValue, -1);
}
// the special cases are symmetric when going up
// A = the number of levels that the child is cached up
$A = $this->_cache[$childIdValue][2];
// B = the number of levels that the parent is cached up
$B = $this->_cache[$parentIdValue][2];
// if B < A-1 AND B >= 0 then cache up the parent A-1 levels
if ($B < $A - 1 && $B >= 0) {
$this->_traverseUp($parentIdValue, $A - 1);
}
// if A < 0 AND B >= 0 then cache up the parent fully
if ($A < 0 && $B >= 0) {
$this->_traverseUp($parentIdValue, -1);
}
// now add the new node as a parent
// 1) update the cache
$this->_tree->addNode($childTreeNode, $parentTreeNode, true);
// 2) update the database
if (isset($this->harmoni_db)) {
if (!isset($this->addParent_stmt)) {
$query = $this->harmoni_db->insert();
$query->setTable("az2_j_node_node");
$query->addRawValue("fk_hierarchy", '?');
$query->addRawValue("fk_parent", '?');
$query->addRawValue("fk_child", '?');
$this->addParent_stmt = $query->prepare();
}
$this->addParent_stmt->bindValue(1, $this->_hierarchyId);
$this->addParent_stmt->bindValue(2, $parentIdValue);
$this->addParent_stmt->bindValue(3, $childIdValue);
$this->addParent_stmt->execute();
$queryResult = $this->addParent_stmt->getResult();
} else {
$dbHandler = Services::getService("DatabaseManager");
$query = new InsertQuery();
$query->setTable("az2_j_node_node");
$query->addValue("fk_hierarchy", $this->_hierarchyId);
$query->addValue("fk_parent", $parentIdValue);
$query->addValue("fk_child", $childIdValue);
// echo "<pre>\n";
// echo MySQL_SQLGenerator::generateSQLQuery($query);
// echo "</pre>\n";
$queryResult = $dbHandler->query($query, $this->_dbIndex);
}
if ($queryResult->getNumberOfRows() != 1) {
throw new OperationFailedException($queryResult->getNumberOfRows() . " rows found. Expecting 1.");
}
// Update the ancestory table
$this->rebuildSubtreeAncestory($child->getId());
}
/**
* Traverse a Hierarchy returning information about each Node encountered.
*
* @param object Id $startId
* @param int $mode
* @param int $direction
* @param int $levels
*
* @return object TraversalInfoIterator
*
* @throws object HierarchyException An exception with one of
* the following messages defined in
* org.osid.hierarchy.HierarchyException may be thrown: {@link
* org.osid.hierarchy.HierarchyException#OPERATION_FAILED
* OPERATION_FAILED}, {@link
* org.osid.hierarchy.HierarchyException#PERMISSION_DENIED
* PERMISSION_DENIED}, {@link
* org.osid.hierarchy.HierarchyException#CONFIGURATION_ERROR
* CONFIGURATION_ERROR}, {@link
* org.osid.hierarchy.HierarchyException#UNIMPLEMENTED
* UNIMPLEMENTED}, {@link
* org.osid.hierarchy.HierarchyException#NODE_TYPE_NOT_FOUND
* NODE_TYPE_NOT_FOUND}, {@link
* org.osid.hierarchy.HierarchyException#UNKNOWN_TRAVERSAL_MODE
* UNKNOWN_TRAVERSAL_MODE}, {@link
* org.osid.hierarchy.HierarchyException#UNKNOWN_TRAVERSAL_DIRECTION
* UNKNOWN_TRAVERSAL_DIRECTION}
*
* @access public
*/
function traverse(Id $startId, $mode, $direction, $levels)
{
// Check the arguments
ArgumentValidator::validate($mode, IntegerValidatorRule::getRule());
ArgumentValidator::validate($direction, IntegerValidatorRule::getRule());
ArgumentValidator::validate($levels, IntegerValidatorRule::getRule());
if ($mode != Hierarchy::TRAVERSE_MODE_DEPTH_FIRST) {
// Only depth-first traversal is supported in the current implementation.
throwError(new Error(HierarchyException::UNKNOWN_TRAVERSAL_DIRECTION(), "Hierarchy", true));
}
$down = $direction == Hierarchy::TRAVERSE_DIRECTION_DOWN;
$result = $this->_cache->traverse($startId, $down, $levels);
return $result;
}
