Code Coverage |
||||||||||
Lines |
Functions and Methods |
Classes and Traits |
||||||||
| Total | |
0.00% |
0 / 27 |
|
0.00% |
0 / 2 |
CRAP | |
0.00% |
0 / 1 |
| SearchDepthFirstPostorder | |
0.00% |
0 / 27 |
|
0.00% |
0 / 2 |
90 | |
0.00% |
0 / 1 |
| rewind | |
0.00% |
0 / 2 |
|
0.00% |
0 / 1 |
2 | |||
| getMovementDirection | |
0.00% |
0 / 25 |
|
0.00% |
0 / 1 |
72 | |||
| 1 | <?php |
| 2 | |
| 3 | /** |
| 4 | * @author: Doug Wilbourne (dougwilbourne@gmail.com) |
| 5 | */ |
| 6 | declare(strict_types=1); |
| 7 | |
| 8 | namespace pvc\struct\treesearch; |
| 9 | |
| 10 | use pvc\interfaces\struct\treesearch\NodeVisitableInterface; |
| 11 | use pvc\interfaces\struct\treesearch\VisitStatus; |
| 12 | |
| 13 | /** |
| 14 | * @template NodeIdType of array-key |
| 15 | * @template NodeType of NodeVisitableInterface |
| 16 | * @extends SearchDepthFirst<NodeIdType, NodeType> |
| 17 | */ |
| 18 | class SearchDepthFirstPostorder extends SearchDepthFirst |
| 19 | { |
| 20 | public function rewind(): void |
| 21 | { |
| 22 | parent::rewind(); |
| 23 | /** |
| 24 | * The rewind method of the parent sets the current node to be the start node. This is correct for |
| 25 | * breadth first and depth first preorder searches. But for depth-first-postorder searches, we want to recurse |
| 26 | * to the bottom of the tree so that the first node returned is at the bottom of the tree. |
| 27 | */ |
| 28 | $this->next(); |
| 29 | } |
| 30 | |
| 31 | /** |
| 32 | * getMovementDirection |
| 33 | * |
| 34 | * @return Direction |
| 35 | * |
| 36 | * returns MOVE_DOWN if we should keep iterating by recursing down through child nodes, |
| 37 | * returns STOP if we should stop iterating |
| 38 | * returns MOVE_UP if we should continue iterating by returning up to the parent |
| 39 | * |
| 40 | * in post order mode, we go from never visited to partially visited and keep moving down if we can move down. |
| 41 | * if we cannot, we go to fully visited and stop |
| 42 | * |
| 43 | * in post order mode we go from partially visited to fully visited if all the children have been visited |
| 44 | * otherwise we move down. |
| 45 | * |
| 46 | * if a node is fully visited we always keep going up. |
| 47 | * |
| 48 | */ |
| 49 | protected function getMovementDirection(): Direction |
| 50 | { |
| 51 | assert(!is_null($this->current())); |
| 52 | |
| 53 | switch ($this->current()->getVisitStatus()) { |
| 54 | case VisitStatus::NEVER_VISITED: |
| 55 | if ($this->allChildrenFullyVisited() || $this->atMaxLevels()) { |
| 56 | $this->current()->setVisitStatus( |
| 57 | VisitStatus::FULLY_VISITED |
| 58 | ); |
| 59 | $direction = Direction::DONT_MOVE; |
| 60 | } else { |
| 61 | $this->current()->setVisitStatus( |
| 62 | VisitStatus::PARTIALLY_VISITED |
| 63 | ); |
| 64 | $direction = Direction::MOVE_DOWN; |
| 65 | } |
| 66 | break; |
| 67 | |
| 68 | case VisitStatus::PARTIALLY_VISITED: |
| 69 | if ($this->allChildrenFullyVisited() || $this->atMaxLevels()) { |
| 70 | $this->current()->setVisitStatus( |
| 71 | VisitStatus::FULLY_VISITED |
| 72 | ); |
| 73 | $direction = Direction::DONT_MOVE; |
| 74 | } else { |
| 75 | $direction = Direction::MOVE_DOWN; |
| 76 | } |
| 77 | break; |
| 78 | |
| 79 | case VisitStatus::FULLY_VISITED: |
| 80 | $direction = Direction::MOVE_UP; |
| 81 | break; |
| 82 | } |
| 83 | |
| 84 | return $direction; |
| 85 | } |
| 86 | } |