<?php
declare(strict_types=1);
namespace PhpMyAdmin\SqlParser\Components;
use PhpMyAdmin\SqlParser\Component;
use PhpMyAdmin\SqlParser\Parser;
use PhpMyAdmin\SqlParser\Token;
use PhpMyAdmin\SqlParser\TokensList;
use function implode;
use function in_array;
use function is_array;
use function trim;
/**
* `WHERE` keyword parser.
*
* @final
*/
class Condition extends Component
{
/**
* Logical operators that can be used to delimit expressions.
*
* @var string[]
*/
public static $DELIMITERS = [
'&&',
'||',
'AND',
'OR',
'XOR',
];
/**
* List of allowed reserved keywords in conditions.
*
* @var array<string, int>
*/
public static $ALLOWED_KEYWORDS = [
'ALL' => 1,
'AND' => 1,
'BETWEEN' => 1,
'EXISTS' => 1,
'IF' => 1,
'IN' => 1,
'INTERVAL' => 1,
'IS' => 1,
'LIKE' => 1,
'MATCH' => 1,
'NOT IN' => 1,
'NOT NULL' => 1,
'NOT' => 1,
'NULL' => 1,
'OR' => 1,
'REGEXP' => 1,
'RLIKE' => 1,
'SOUNDS' => 1,
'XOR' => 1,
];
/**
* Identifiers recognized.
*
* @var array<int, mixed>
*/
public $identifiers = [];
/**
* Whether this component is an operator.
*
* @var bool
*/
public $isOperator = false;
/**
* The condition.
*
* @var string
*/
public $expr;
/**
* @param string $expr the condition or the operator
*/
public function __construct($expr = null)
{
$this->expr = trim((string) $expr);
}
/**
* @param Parser $parser the parser that serves as context
* @param TokensList $list the list of tokens that are being parsed
* @param array<string, mixed> $options parameters for parsing
*
* @return Condition[]
*/
public static function parse(Parser $parser, TokensList $list, array $options = [])
{
$ret = [];
$expr = new static();
/**
* Counts brackets.
*
* @var int
*/
$brackets = 0;
/**
* Whether there was a `BETWEEN` keyword before or not.
*
* It is required to keep track of them because their structure contains
* the keyword `AND`, which is also an operator that delimits
* expressions.
*
* @var bool
*/
$betweenBefore = false;
for (; $list->idx < $list->count; ++$list->idx) {
/**
* Token parsed at this moment.
*/
$token = $list->tokens[$list->idx];
// End of statement.
if ($token->type === Token::TYPE_DELIMITER) {
break;
}
// Skipping whitespaces and comments.
if ($token->type === Token::TYPE_COMMENT) {
continue;
}
// Replacing all whitespaces (new lines, tabs, etc.) with a single
// space character.
if ($token->type === Token::TYPE_WHITESPACE) {
$expr->expr .= ' ';
continue;
}
// Conditions are delimited by logical operators.
if (in_array($token->value, static::$DELIMITERS, true)) {
if ($betweenBefore && ($token->value === 'AND')) {
// The syntax of keyword `BETWEEN` is hard-coded.
$betweenBefore = false;
} else {
// The expression ended.
$expr->expr = trim($expr->expr);
if (! empty($expr->expr)) {
$ret[] = $expr;
}
// Adding the operator.
$expr = new static($token->value);
$expr->isOperator = true;
$ret[] = $expr;
// Preparing to parse another condition.
$expr = new static();
continue;
}
}
if (
($token->type === Token::TYPE_KEYWORD)
&& ($token->flags & Token::FLAG_KEYWORD_RESERVED)
&& ! ($token->flags & Token::FLAG_KEYWORD_FUNCTION)
) {
if ($token->value === 'BETWEEN') {
$betweenBefore = true;
}
if (($brackets === 0) && empty(static::$ALLOWED_KEYWORDS[$token->value])) {
break;
}
}
if ($token->type === Token::TYPE_OPERATOR) {
if ($token->value === '(') {
++$brackets;
} elseif ($token->value === ')') {
if ($brackets === 0) {
break;
}
--$brackets;
}
}
$expr->expr .= $token->token;
if (
($token->type !== Token::TYPE_NONE)
&& (($token->type !== Token::TYPE_KEYWORD)
|| ($token->flags & Token::FLAG_KEYWORD_RESERVED))
&& ($token->type !== Token::TYPE_STRING)
&& ($token->type !== Token::TYPE_SYMBOL)
) {
continue;
}
if (in_array($token->value, $expr->identifiers)) {
continue;
}
$expr->identifiers[] = $token->value;
}
// Last iteration was not processed.
$expr->expr = trim($expr->expr);
if (! empty($expr->expr)) {
$ret[] = $expr;
}
--$list->idx;
return $ret;
}
/**
* @param Condition[] $component the component to be built
* @param array<string, mixed> $options parameters for building
*
* @return string
*/
public static function build($component, array $options = [])
{
if (is_array($component)) {
return implode(' ', $component);
}
return $component->expr;
}
}