programming-examples/php/Algo/Base1.php
2019-11-15 12:59:38 +01:00

57 lines
1.7 KiB
PHP

<?php
namespace Graphp\Algorithms\Search;
use Graphp\Algorithms\BaseVertex;
use Fhaculty\Graph\Exception\DomainException;
use Fhaculty\Graph\Exception\InvalidArgumentException;
use Fhaculty\Graph\Vertex;
use Fhaculty\Graph\Set\Vertices;
abstract class Base extends BaseVertex
{
const DIRECTION_FORWARD = 0;
const DIRECTION_REVERSE = 1;
const DIRECTION_BOTH = 2;
private $direction = self::DIRECTION_FORWARD;
/**
* set direction in which to follow adjacent vertices
*
* @param int $direction
* @return AlgorithmSearch $this (chainable)
* @throws Exception
* @see AlgorithmSearch::getVerticesAdjacent()
*/
public function setDirection($direction)
{
if ($direction !== self::DIRECTION_FORWARD && $direction !== self::DIRECTION_REVERSE && $direction !== self::DIRECTION_BOTH) {
throw new InvalidArgumentException('Invalid direction given');
}
$this->direction = $direction;
return $this;
}
protected function getVerticesAdjacent(Vertex $vertex)
{
if ($this->direction === self::DIRECTION_FORWARD) {
return $vertex->getVerticesEdgeTo();
} elseif ($this->direction === self::DIRECTION_REVERSE) {
return $vertex->getVerticesEdgeFrom();
} elseif ($this->direction === self::DIRECTION_BOTH) {
return $vertex->getVerticesEdge();
} else {
throw new DomainException('Should not happen. Invalid direction setting');
}
}
/**
* get set of all Vertices that can be reached from start vertex
*
* @return Vertices
*/
abstract public function getVertices();
}