/**
* Checks whether if an item exists on the queried path or not
* @param string $query
* @return bool
*/
public function exists($query)
{
if (empty($query)) {
throw new \InvalidArgumentException('Argument 1 should not be empty.');
}
$keyExists = 'exists' . $this->type;
$key = '';
$result = null;
while (strlen($key .= $this->shiftKey($query)) > 0 and $result === null) {
$realKey = $this->parseKey($key);
if ($this->{$keyExists}($realKey)) {
switch ($this->type) {
case static::TYPE_ARRAY:
$result =& $this->object[$realKey];
break;
case static::TYPE_ACCESS:
if ($key[0] !== '@' and $key[0] !== '!' and $this->object->offsetExists($realKey)) {
$result =& $this->object->offsetGet($realKey);
break;
}
case static::TYPE_OBJECT:
if ($key[0] === '@') {
$call = $this->object[$realKey];
if (!$call instanceof Provider) {
throw new \RuntimeException('"' . $key . '" is not a Provider. Using "@" (service-getter) prefix only allowed on Provider item.');
}
$result = $call($this->object);
} else {
if ($key[0] == '!') {
$call = $this->object[$realKey];
if (!$call instanceof Provider) {
throw new \RuntimeException('"' . $key . '" is not a Provider. Using "!" (mutation-getter) prefix only allowed on Provider item.');
}
if (!$call->isMutated()) {
throw new \RuntimeException('Provider "' . $key . '" is not mutated.');
}
$result =& $call->getMutatedItem();
} else {
$result =& $this->object->{$realKey};
}
}
break;
}
if ($query !== '' and (is_array($result) or is_object($result))) {
$q = new static($result);
if ($q->exists($query)) {
$result =& QueryParser::Create($result)->find($query);
} else {
return false;
}
}
} else {
if ($query === '') {
return false;
}
}
}
return true;
}
