private static function validEndpoint(Fields $fields, Coords $spot, $shipSize, $direction)
{
/** @var Field $field */
$field = $fields->at($spot);
if ($field->occupied()) {
return;
}
if (!$fields->hasAt($spot->{$direction}($shipSize - 1))) {
return;
}
$neighbour = null;
for ($i = 1; $i < $shipSize; $i++) {
$neighbour = $fields->at($spot->{$direction}($i));
if ($neighbour->occupied()) {
return;
}
}
if ($neighbour === null) {
return;
}
return $neighbour->coords();
}
/**
* @return Ship[]
*/
public function ships()
{
return $this->fields->ships();
}