<?php
declare(strict_types=1);
namespace PhpMyAdmin\SqlParser;
use ArrayAccess;
use function count;
use function is_array;
use function is_string;
/**
* Defines an array of tokens and utility functions to iterate through it.
*
* A structure representing a list of tokens.
*
* @implements ArrayAccess<int, Token>
*/
class TokensList implements ArrayAccess
{
/**
* The array of tokens.
*
* @var Token[]
*/
public $tokens = [];
/**
* The count of tokens.
*
* @var int
*/
public $count = 0;
/**
* The index of the next token to be returned.
*
* @var int
*/
public $idx = 0;
/**
* @param Token[] $tokens the initial array of tokens
* @param int $count the count of tokens in the initial array
*/
public function __construct(array $tokens = [], $count = -1)
{
if (empty($tokens)) {
return;
}
$this->tokens = $tokens;
$this->count = $count === -1 ? count($tokens) : $count;
}
/**
* Builds an array of tokens by merging their raw value.
*
* @param string|Token[]|TokensList $list the tokens to be built
*
* @return string
*/
public static function build($list)
{
if (is_string($list)) {
return $list;
}
if ($list instanceof self) {
$list = $list->tokens;
}
$ret = '';
if (is_array($list)) {
foreach ($list as $tok) {
$ret .= $tok->token;
}
}
return $ret;
}
/**
* Adds a new token.
*
* @param Token $token token to be added in list
*
* @return void
*/
public function add(Token $token)
{
$this->tokens[$this->count++] = $token;
}
/**
* Gets the next token. Skips any irrelevant token (whitespaces and
* comments).
*
* @return Token|null
*/
public function getNext()
{
for (; $this->idx < $this->count; ++$this->idx) {
if (
($this->tokens[$this->idx]->type !== Token::TYPE_WHITESPACE)
&& ($this->tokens[$this->idx]->type !== Token::TYPE_COMMENT)
) {
return $this->tokens[$this->idx++];
}
}
return null;
}
/**
* Gets the previous token. Skips any irrelevant token (whitespaces and
* comments).
*/
public function getPrevious(): ?Token
{
for (; $this->idx > 0; --$this->idx) {
if (
($this->tokens[$this->idx]->type !== Token::TYPE_WHITESPACE)
&& ($this->tokens[$this->idx]->type !== Token::TYPE_COMMENT)
) {
return $this->tokens[$this->idx--];
}
}
return null;
}
/**
* Gets the next token.
*
* @param int $type the type
*
* @return Token|null
*/
public function getNextOfType($type)
{
for (; $this->idx < $this->count; ++$this->idx) {
if ($this->tokens[$this->idx]->type === $type) {
return $this->tokens[$this->idx++];
}
}
return null;
}
/**
* Gets the next token.
*
* @param int $type the type of the token
* @param string $value the value of the token
*
* @return Token|null
*/
public function getNextOfTypeAndValue($type, $value)
{
for (; $this->idx < $this->count; ++$this->idx) {
if (($this->tokens[$this->idx]->type === $type) && ($this->tokens[$this->idx]->value === $value)) {
return $this->tokens[$this->idx++];
}
}
return null;
}
/**
* Gets the next token.
*
* @param int $type the type of the token
* @param int $flag the flag of the token
*/
public function getNextOfTypeAndFlag(int $type, int $flag): ?Token
{
for (; $this->idx < $this->count; ++$this->idx) {
if (($this->tokens[$this->idx]->type === $type) && ($this->tokens[$this->idx]->flags === $flag)) {
return $this->tokens[$this->idx++];
}
}
return null;
}
/**
* Sets an value inside the container.
*
* @param int|null $offset the offset to be set
* @param Token $value the token to be saved
*
* @return void
*/
#[\ReturnTypeWillChange]
public function offsetSet($offset, $value)
{
if ($offset === null) {
$this->tokens[$this->count++] = $value;
} else {
$this->tokens[$offset] = $value;
}
}
/**
* Gets a value from the container.
*
* @param int $offset the offset to be returned
*
* @return Token|null
*/
#[\ReturnTypeWillChange]
public function offsetGet($offset)
{
return $offset < $this->count ? $this->tokens[$offset] : null;
}
/**
* Checks if an offset was previously set.
*
* @param int $offset the offset to be checked
*
* @return bool
*/
#[\ReturnTypeWillChange]
public function offsetExists($offset)
{
return $offset < $this->count;
}
/**
* Unsets the value of an offset.
*
* @param int $offset the offset to be unset
*
* @return void
*/
#[\ReturnTypeWillChange]
public function offsetUnset($offset)
{
unset($this->tokens[$offset]);
--$this->count;
for ($i = $offset; $i < $this->count; ++$i) {
$this->tokens[$i] = $this->tokens[$i + 1];
}
unset($this->tokens[$this->count]);
}
}