Yoanm\CommonDSA\Factory\BinaryTreeFactory::fromLevelOrderList()

Complexity

Conditions	8
Paths	6

Size

Total Lines	33
Code Lines	18

Duplication

Lines	0
Ratio	0 %

Code Coverage

Tests	19
CRAP Score	8

Importance

Changes	1
Bugs	0	Features	0

<?php
    public static function fromLevelOrderList(array $list, callable $nodeCreator): ?Node
    {
        $tailIdx = count($list) - 1;
        if ($tailIdx < 0 || (0 === $tailIdx && null === $list[0])) {
            return null;
        }

        /** @var SplQueue<Node> $queue */
        $queue = new SplQueue();

        $root = call_user_func($nodeCreator, $list[0]); // @phpstan-ignore argument.type
        $queue->enqueue($root);

        $idx = 1; // Root value already managed, hence 1 rather 0 !
        while ($idx <= $tailIdx) {
            $parentNode = $queue->dequeue();

            // 1. Manage left node value
            if (null !== $list[$idx]) {
                $parentNode->left = $node = call_user_func($nodeCreator, $list[$idx]);
                $queue->enqueue($node);
            }
            ++$idx;

            // 1. Manage right node value (if it exists !)
            if ($idx <= $tailIdx && null !== $list[$idx]) {
                $parentNode->right = $node = call_user_func($nodeCreator, $list[$idx]);
                $queue->enqueue($node);
            }
            ++$idx;
        }

        return $root;
    }