<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <[email protected]>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\Routing\Matcher\Dumper;
use Symfony\Component\Routing\RouteCollection;
/**
* Prefix tree of routes preserving routes order.
*
* @author Frank de Jonge <[email protected]>
* @author Nicolas Grekas <[email protected]>
*
* @internal
*/
class StaticPrefixCollection
{
private $prefix;
/**
* @var string[]
*/
private $staticPrefixes = [];
/**
* @var string[]
*/
private $prefixes = [];
/**
* @var array[]|self[]
*/
private $items = [];
public function __construct(string $prefix = '/')
{
$this->prefix = $prefix;
}
public function getPrefix(): string
{
return $this->prefix;
}
/**
* @return array[]|self[]
*/
public function getRoutes(): array
{
return $this->items;
}
/**
* Adds a route to a group.
*
* @param array|self $route
*/
public function addRoute(string $prefix, $route)
{
[$prefix, $staticPrefix] = $this->getCommonPrefix($prefix, $prefix);
for ($i = \count($this->items) - 1; 0 <= $i; --$i) {
$item = $this->items[$i];
[$commonPrefix, $commonStaticPrefix] = $this->getCommonPrefix($prefix, $this->prefixes[$i]);
if ($this->prefix === $commonPrefix) {
// the new route and a previous one have no common prefix, let's see if they are exclusive to each others
if ($this->prefix !== $staticPrefix && $this->prefix !== $this->staticPrefixes[$i]) {
// the new route and the previous one have exclusive static prefixes
continue;
}
if ($this->prefix === $staticPrefix && $this->prefix === $this->staticPrefixes[$i]) {
// the new route and the previous one have no static prefix
break;
}
if ($this->prefixes[$i] !== $this->staticPrefixes[$i] && $this->prefix === $this->staticPrefixes[$i]) {
// the previous route is non-static and has no static prefix
break;
}
if ($prefix !== $staticPrefix && $this->prefix === $staticPrefix) {
// the new route is non-static and has no static prefix
break;
}
continue;
}
if ($item instanceof self && $this->prefixes[$i] === $commonPrefix) {
// the new route is a child of a previous one, let's nest it
$item->addRoute($prefix, $route);
} else {
// the new route and a previous one have a common prefix, let's merge them
$child = new self($commonPrefix);
[$child->prefixes[0], $child->staticPrefixes[0]] = $child->getCommonPrefix($this->prefixes[$i], $this->prefixes[$i]);
[$child->prefixes[1], $child->staticPrefixes[1]] = $child->getCommonPrefix($prefix, $prefix);
$child->items = [$this->items[$i], $route];
$this->staticPrefixes[$i] = $commonStaticPrefix;
$this->prefixes[$i] = $commonPrefix;
$this->items[$i] = $child;
}
return;
}
// No optimised case was found, in this case we simple add the route for possible
// grouping when new routes are added.
$this->staticPrefixes[] = $staticPrefix;
$this->prefixes[] = $prefix;
$this->items[] = $route;
}
/**
* Linearizes back a set of nested routes into a collection.
*/
public function populateCollection(RouteCollection $routes): RouteCollection
{
foreach ($this->items as $route) {
if ($route instanceof self) {
$route->populateCollection($routes);
} else {
$routes->add(...$route);
}
}
return $routes;
}
/**
* Gets the full and static common prefixes between two route patterns.
*
* The static prefix stops at last at the first opening bracket.
*/
private function getCommonPrefix(string $prefix, string $anotherPrefix): array
{
$baseLength = \strlen($this->prefix);
$end = min(\strlen($prefix), \strlen($anotherPrefix));
$staticLength = null;
set_error_handler([__CLASS__, 'handleError']);
for ($i = $baseLength; $i < $end && $prefix[$i] === $anotherPrefix[$i]; ++$i) {
if ('(' === $prefix[$i]) {
$staticLength = $staticLength ?? $i;
for ($j = 1 + $i, $n = 1; $j < $end && 0 < $n; ++$j) {
if ($prefix[$j] !== $anotherPrefix[$j]) {
break 2;
}
if ('(' === $prefix[$j]) {
++$n;
} elseif (')' === $prefix[$j]) {
--$n;
} elseif ('\\' === $prefix[$j] && (++$j === $end || $prefix[$j] !== $anotherPrefix[$j])) {
--$j;
break;
}
}
if (0 < $n) {
break;
}
if (('?' === ($prefix[$j] ?? '') || '?' === ($anotherPrefix[$j] ?? '')) && ($prefix[$j] ?? '') !== ($anotherPrefix[$j] ?? '')) {
break;
}
$subPattern = substr($prefix, $i, $j - $i);
if ($prefix !== $anotherPrefix && !preg_match('/^\(\[[^\]]++\]\+\+\)$/', $subPattern) && !preg_match('{(?<!'.$subPattern.')}', '')) {
// sub-patterns of variable length are not considered as common prefixes because their greediness would break in-order matching
break;
}
$i = $j - 1;
} elseif ('\\' === $prefix[$i] && (++$i === $end || $prefix[$i] !== $anotherPrefix[$i])) {
--$i;
break;
}
}
restore_error_handler();
if ($i < $end && 0b10 === (\ord($prefix[$i]) >> 6) && preg_match('//u', $prefix.' '.$anotherPrefix)) {
do {
// Prevent cutting in the middle of an UTF-8 characters
--$i;
} while (0b10 === (\ord($prefix[$i]) >> 6));
}
return [substr($prefix, 0, $i), substr($prefix, 0, $staticLength ?? $i)];
}
public static function handleError($type, $msg)
{
return false !== strpos($msg, 'Compilation failed: lookbehind assertion is not fixed length');
}
}