/**
* Do rotations on related places on deletion
*
* @param Node $node
* @return $this
*/
protected function deleteSort(Node $node)
{
// If is root or black, go back
if (Node::COLOR_BLACK !== $node->getColor() || null === $node->getParent()) {
return $this;
}
$direction = $node->getPosition();
$tmp = $node->getParent()->getChild(-$direction);
if (null !== $tmp) {
if (Node::COLOR_RED === $tmp->getColor()) {
$tmp->setColor(Node::COLOR_BLACK);
$node->getParent()->setColor(Node::COLOR_RED);
$this->rotate($node->getParent(), $direction);
$tmp = $node->getParent()->getChild(-$direction);
}
if ($tmp->haveChild(Node::POSITION_LEFT) && $tmp->getChild(Node::POSITION_LEFT)->getColor() === Node::COLOR_BLACK && $tmp->haveChild(Node::POSITION_RIGHT) && $tmp->getChild(Node::POSITION_RIGHT)->getColor() === Node::COLOR_BLACK) {
$tmp->setColor(Node::COLOR_RED);
return $this->deleteSort($node->getParent());
} else {
if ($tmp->haveChild(-$direction) && $tmp->getChild(-$direction)->getColor() === Node::COLOR_BLACK) {
if ($tmp->haveChild($direction)) {
$tmp->getChild($direction)->setColor(Node::COLOR_BLACK);
}
$tmp->setColor(Node::COLOR_RED);
$this->rotate($tmp, -$direction);
$tmp = $node->getParent()->getChild(-$direction);
}
$tmp->setColor($node->getParent()->getColor());
$node->getParent()->setColor(Node::COLOR_BLACK);
if ($tmp->getChild(-$direction)) {
$tmp->getChild(-$direction)->setColor(Node::COLOR_BLACK);
}
$this->rotate($node->getParent(), $direction);
$node = $this->root;
}
}
return $this->deleteSort($node->setColor(Node::COLOR_BLACK));
}
/**
* Simple recursive visualisation.
* The first node should be the root.
* Colors are for linux console, sorry windows guys :p
*
* @param Node $node
* @param string $indent
* @return string The max indentation
*/
protected function infixeRender(Node $node, $indent = '')
{
if (!$node->isLeaf() && $node->haveChild(Node::POSITION_LEFT)) {
// Show left side first
$this->infixeRender($node->getChild(Node::POSITION_LEFT), $indent . ' ');
}
echo sprintf('%s%s#%d', $indent, $node->getPosition() == 0 ? '-' : ($node->getPosition() > 0 ? '\\' : '/'), $node->getId());
echo ' L#' . ($node->haveChild(Node::POSITION_LEFT) ? $node->getChild(Node::POSITION_LEFT)->getId() : '-');
echo ' R#' . ($node->haveChild(Node::POSITION_RIGHT) ? $node->getChild(Node::POSITION_RIGHT)->getId() : '-');
echo ' P#' . (null !== $node->getParent() ? $node->getParent()->getId() : '-');
echo ' C:' . (Node::COLOR_RED === $node->getColor() ? "[0;31mRED[0m" : "[0;32mBLACK[0m");
echo PHP_EOL;
if (!$node->isLeaf() && $node->haveChild(Node::POSITION_RIGHT)) {
// Show left side first
$this->infixeRender($node->getChild(Node::POSITION_RIGHT), $indent . ' ');
}
}
