/**
* Run the pathfinder algorithm
*
* @return \SplStack
*/
public function run()
{
$start = $this->start;
$goal = $this->goal;
$open = new Set([$start], function (NodeInterface $node) use($goal) {
return $this->getHeuristic($goal, $node);
});
$closed = new Set();
$open->add($start);
$path = new \SplStack();
$step = null;
while (!$open->isEmpty()) {
$current = $open->current();
$path->push($current->getNode());
$step = new Step($current->getNode(), $step);
if ($current->getNode() == $goal) {
break;
}
$closed->add($current->getNode());
$neighbours = $current->getNode()->getNeighbours();
foreach ($neighbours as $neighbour) {
if ($closed->has($neighbour)) {
continue;
}
if (!$open->has($neighbour)) {
$open->add($neighbour, $this->getHeuristic($current->getNode(), $neighbour) + $neighbour->getCost());
}
}
}
return $path;
}
/**
* Test constructor adds nodes and the heuristic callback
*/
public function testConstruct()
{
$nodes = [new Node(1, 1)];
$heuristic = function (NodeInterface $node) {
return rand(1, 10);
};
$set = new Set($nodes, $heuristic);
$this->assertEquals($heuristic, $set->getHeuristic());
$this->assertEquals(current($nodes), current($set->getItems())->getNode());
}