<?php

/*
 * This file is part of the Symfony package.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *
 * For the full copyright and license information, please view the LICENSE
 * file that was distributed with this source code.
 */

namespace Symfony\Component\Validator\Constraints;

use Symfony\Component\Validator\Constraint;
use Symfony\Component\Validator\ConstraintValidator;
use Symfony\Component\Validator\Exception\UnexpectedTypeException;
use Symfony\Component\Validator\Exception\UnexpectedValueException;

/**
 * @author Bernhard Schussek <bschussek@gmail.com>
 */
class UrlValidator extends ConstraintValidator
{
    public const PATTERN = <<<'REGEX'
        {^
            (%s)://                                 # protocol
            ((?:[\pL\pN\-._~!$&'()*+,;=]|%%[0-9A-Fa-f]{2})++(?::(?:[:\pL\pN\-._~!$&'()*+,;=]|%%[0-9A-Fa-f]{2})*+)?@)?  # basic auth
            (
                (?:
                    (?:
                        (?:[\pL\pN\pS\pM\-\_]++\.)+
                        (?:
                            (?:xn--[a-z0-9-]++)     # punycode in tld
                            |
                            (?:[\pL\pN\pM]++)       # no punycode in tld
                        )
                    )                               # a multi-level domain name
                        |
                    [a-z0-9\-\_]++                  # a single-level domain name
                )\.?
                    |                               # or
                \d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}  # an IP address
                    |                               # or
                \[
                    (?:(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){6})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:::(?:(?:(?:[0-9a-f]{1,4})):){5})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:[0-9a-f]{1,4})))?::(?:(?:(?:[0-9a-f]{1,4})):){4})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,1}(?:(?:[0-9a-f]{1,4})))?::(?:(?:(?:[0-9a-f]{1,4})):){3})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,2}(?:(?:[0-9a-f]{1,4})))?::(?:(?:(?:[0-9a-f]{1,4})):){2})(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,3}(?:(?:[0-9a-f]{1,4})))?::(?:(?:[0-9a-f]{1,4})):)(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,4}(?:(?:[0-9a-f]{1,4})))?::)(?:(?:(?:(?:(?:[0-9a-f]{1,4})):(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9]))\.){3}(?:(?:25[0-5]|(?:[1-9]|1[0-9]|2[0-4])?[0-9])))))))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,5}(?:(?:[0-9a-f]{1,4})))?::)(?:(?:[0-9a-f]{1,4})))|(?:(?:(?:(?:(?:(?:[0-9a-f]{1,4})):){0,6}(?:(?:[0-9a-f]{1,4})))?::))))
                \]  # an IPv6 address
            )
            (:[0-9]+)?                              # a port (optional)
            (?:/ (?:[\pL\pN\pS\pM\-._~!$&'()*+,;=:@]|%%[0-9A-Fa-f]{2})* )*  # a path
            (?:\? (?:[\pL\pN\-._~!$&'()*+,;=:@/?[\]]|%%[0-9A-Fa-f]{2})* )?  # a query (optional)
            (?:\# (?:[\pL\pN\-._~!$&'()*+,;=:@/?]|%%[0-9A-Fa-f]{2})* )?     # a fragment (optional)
        $}ixuD
        REGEX;

    public function validate(mixed $value, Constraint $constraint): void
    {
        if (!$constraint instanceof Url) {
            throw new UnexpectedTypeException($constraint, Url::class);
        }

        if (null === $value || '' === $value) {
            return;
        }

        if (!\is_scalar($value) && !$value instanceof \Stringable) {
            throw new UnexpectedValueException($value, 'string');
        }

        $value = (string) $value;
        if ('' === $value) {
            return;
        }

        if (null !== $constraint->normalizer) {
            $value = ($constraint->normalizer)($value);
        }

        if (['*'] === $constraint->protocols) {
            // Use RFC 3986 compliant scheme pattern: scheme = ALPHA *( ALPHA / DIGIT / "+" / "-" / "." )
            $protocols = '[a-zA-Z][a-zA-Z0-9+.-]*';
        } else {
            $protocols = implode('|', $constraint->protocols);
        }

        $pattern = $constraint->relativeProtocol ? str_replace('(%s):', '(?:(%s):)?', static::PATTERN) : static::PATTERN;
        $pattern = \sprintf($pattern, $protocols);

        if (!preg_match($pattern, $value)) {
            $this->context->buildViolation($constraint->message)
                ->setParameter('{{ value }}', $this->formatValue($value))
                ->setCode(Url::INVALID_URL_ERROR)
                ->addViolation();

            return;
        }

        if ($constraint->requireTld) {
            $urlHost = parse_url($value, \PHP_URL_HOST);
            // the host of URLs with a TLD must include at least a '.' (but it can't be an IP address like '127.0.0.1')
            if (!str_contains($urlHost, '.') || filter_var($urlHost, \FILTER_VALIDATE_IP)) {
                $this->context->buildViolation($constraint->tldMessage)
                    ->setParameter('{{ value }}', $this->formatValue($value))
                    ->setCode(Url::MISSING_TLD_ERROR)
                    ->addViolation();
            }
        }
    }
}