Baum\Move::updateStructure PHP Method

    public function updateStructure()
    {
        list($a, $b, $c, $d) = $this->boundaries();
        // select the rows between the leftmost & the rightmost boundaries and apply a lock
        $this->applyLockBetween($a, $d);
        $connection = $this->node->getConnection();
        $grammar = $connection->getQueryGrammar();
        $currentId = $this->quoteIdentifier($this->node->getKey());
        $parentId = $this->quoteIdentifier($this->parentId());
        $leftColumn = $this->node->getLeftColumnName();
        $rightColumn = $this->node->getRightColumnName();
        $parentColumn = $this->node->getParentColumnName();
        $wrappedLeft = $grammar->wrap($leftColumn);
        $wrappedRight = $grammar->wrap($rightColumn);
        $wrappedParent = $grammar->wrap($parentColumn);
        $wrappedId = $grammar->wrap($this->node->getKeyName());
        $lftSql = "CASE\n      WHEN {$wrappedLeft} BETWEEN {$a} AND {$b} THEN {$wrappedLeft} + {$d} - {$b}\n      WHEN {$wrappedLeft} BETWEEN {$c} AND {$d} THEN {$wrappedLeft} + {$a} - {$c}\n      ELSE {$wrappedLeft} END";
        $rgtSql = "CASE\n      WHEN {$wrappedRight} BETWEEN {$a} AND {$b} THEN {$wrappedRight} + {$d} - {$b}\n      WHEN {$wrappedRight} BETWEEN {$c} AND {$d} THEN {$wrappedRight} + {$a} - {$c}\n      ELSE {$wrappedRight} END";
        $parentSql = "CASE\n      WHEN {$wrappedId} = {$currentId} THEN {$parentId}\n      ELSE {$wrappedParent} END";
        $updateConditions = [$leftColumn => $connection->raw($lftSql), $rightColumn => $connection->raw($rgtSql), $parentColumn => $connection->raw($parentSql)];
        if ($this->node->timestamps) {
            $updateConditions[$this->node->getUpdatedAtColumn()] = $this->node->freshTimestamp();
        }
        return $this->node->newNestedSetQuery()->where(function ($query) use($leftColumn, $rightColumn, $a, $d) {
            $query->whereBetween($leftColumn, [$a, $d])->orWhereBetween($rightColumn, [$a, $d]);
        })->update($updateConditions);
    }