/**
* Find a token in the tokenizer. You can search by the token's literal code or name. You can also specify on
* offset for the search. If the offset is negative, the search will be done starting from the end.
*
* @param string|integer $search The token's literal code or name.
* @param integer $offset The offset to start searching from. A negative offest searches from the end.
* @return integer|boolean The index of the token that has been found or false.
*/
public function findToken($search, $offset = 0)
{
if ($search === null) {
throw new \InvalidArgumentException('A token cannot be searched for with a null value.');
} elseif (!is_int($offset)) {
throw new \InvalidArgumentException('On offset must be specified as an integer.');
}
if ($offset >= 0) {
// Offset is greater than zero. Search from left to right
$tokenizer = clone $this;
$is_reversed = false;
} else {
// Offset is negative. Search from right to left
$tokenizer = new Tokenizer(array_reverse($this->tokens));
$offset = abs($offset) - 1;
$is_reversed = true;
}
// Seek to the offset and start the search from there
$tokenizer->seek($offset);
// Loop through the tokens and search for the target token
while ($tokenizer->valid()) {
$token = $tokenizer->current();
if ($token->code === $search || $token->name === $search || $token->value === $search) {
$index = $tokenizer->key();
// Calculate the index as if the tokenizer is not reversed
if ($is_reversed) {
$index = count($tokenizer) - $index - 1;
}
return $index;
}
$tokenizer->next();
}
return false;
}