<?php

declare(strict_types=1);

namespace GuzzleHttp\UriTemplate;

/**
 * Expands URI templates. Userland implementation of PECL uri_template.
 *
 * @see https://datatracker.ietf.org/doc/html/rfc6570
 */
final class UriTemplate
{
    /**
     * @var array<string, array{prefix:string, joiner:string, query:bool}> Hash for quick operator lookups
     */
    private static $operatorHash = [
        '' => ['prefix' => '', 'joiner' => ',', 'query' => false],
        '+' => ['prefix' => '', 'joiner' => ',', 'query' => false],
        '#' => ['prefix' => '#', 'joiner' => ',', 'query' => false],
        '.' => ['prefix' => '.', 'joiner' => '.', 'query' => false],
        '/' => ['prefix' => '/', 'joiner' => '/', 'query' => false],
        ';' => ['prefix' => ';', 'joiner' => ';', 'query' => true],
        '?' => ['prefix' => '?', 'joiner' => '&', 'query' => true],
        '&' => ['prefix' => '&', 'joiner' => '&', 'query' => true],
    ];

    /**
     * @var string[] Delimiters
     */
    private static $delims = [
        ':',
        '/',
        '?',
        '#',
        '[',
        ']',
        '@',
        '!',
        '$',
        '&',
        '\'',
        '(',
        ')',
        '*',
        '+',
        ',',
        ';',
        '=',
    ];

    /**
     * @var string[] Percent encoded delimiters
     */
    private static $delimsPct = [
        '%3A',
        '%2F',
        '%3F',
        '%23',
        '%5B',
        '%5D',
        '%40',
        '%21',
        '%24',
        '%26',
        '%27',
        '%28',
        '%29',
        '%2A',
        '%2B',
        '%2C',
        '%3B',
        '%3D',
    ];

    /**
     * @param array<string,mixed> $variables Variables to use in the template expansion
     *
     * @throws \RuntimeException
     */
    public static function expand(string $template, array $variables): string
    {
        if (false === \strpos($template, '{')) {
            return $template;
        }

        /** @var string|null */
        $result = \preg_replace_callback(
            '/\{([^\}]+)\}/',
            self::expandMatchCallback($variables),
            $template
        );

        if (null === $result) {
            throw new \RuntimeException(\sprintf('Unable to process template: %s', \preg_last_error_msg()));
        }

        return $result;
    }

    /**
     * @param array<string,mixed> $variables Variables to use in the template expansion
     *
     * @return callable(string[]): string
     */
    private static function expandMatchCallback(array $variables): callable
    {
        return static function (array $matches) use ($variables): string {
            return self::expandMatch($matches, $variables);
        };
    }

    /**
     * Process an expansion
     *
     * @param array<string,mixed> $variables Variables to use in the template expansion
     * @param string[]            $matches   Matches met in the preg_replace_callback
     *
     * @return string Returns the replacement string
     */
    private static function expandMatch(array $matches, array $variables): string
    {
        $replacements = [];
        $parsed = self::parseExpression($matches[1]);
        $prefix = self::$operatorHash[$parsed['operator']]['prefix'];
        $joiner = self::$operatorHash[$parsed['operator']]['joiner'];
        $useQuery = self::$operatorHash[$parsed['operator']]['query'];
        $allUndefined = true;

        foreach ($parsed['values'] as $value) {
            if (!isset($variables[$value['value']])) {
                continue;
            }

            $variable = $variables[$value['value']];
            $actuallyUseQuery = $useQuery;
            $expanded = '';

            if (\is_array($variable)) {
                $isAssoc = self::isAssoc($variable);
                $kvp = [];
                /** @var mixed $var */
                foreach ($variable as $key => $var) {
                    if ($isAssoc) {
                        $key = \rawurlencode((string) $key);
                        $isNestedArray = \is_array($var);
                    } else {
                        $isNestedArray = false;
                    }

                    if (!$isNestedArray) {
                        $var = \rawurlencode((string) $var);
                        if ($parsed['operator'] === '+' || $parsed['operator'] === '#') {
                            $var = self::decodeReserved($var);
                        }
                    }

                    if ($value['modifier'] === '*') {
                        if ($isAssoc) {
                            if ($isNestedArray) {
                                // Nested arrays must allow for deeply nested structures.
                                $var = \http_build_query([$key => $var], '', '&', \PHP_QUERY_RFC3986);
                            } else {
                                $var = \sprintf('%s=%s', (string) $key, (string) $var);
                            }
                        } elseif ($key > 0 && $actuallyUseQuery) {
                            $var = \sprintf('%s=%s', $value['value'], (string) $var);
                        }
                    }

                    /** @var string $var */
                    $kvp[$key] = $var;
                }

                if (0 === \count($variable)) {
                    $actuallyUseQuery = false;
                } elseif ($value['modifier'] === '*') {
                    $expanded = \implode($joiner, $kvp);
                    if ($isAssoc) {
                        // Don't prepend the value name when using the explode
                        // modifier with an associative array.
                        $actuallyUseQuery = false;
                    }
                } else {
                    if ($isAssoc) {
                        // When an associative array is encountered and the
                        // explode modifier is not set, then the result must be
                        // a comma separated list of keys followed by their
                        // respective values.
                        foreach ($kvp as $k => &$v) {
                            $v = \sprintf('%s,%s', $k, $v);
                        }
                    }
                    $expanded = \implode(',', $kvp);
                }
            } else {
                $allUndefined = false;
                if ($value['modifier'] === ':' && isset($value['position'])) {
                    $variable = \substr((string) $variable, 0, $value['position']);
                }
                $expanded = \rawurlencode((string) $variable);
                if ($parsed['operator'] === '+' || $parsed['operator'] === '#') {
                    $expanded = self::decodeReserved($expanded);
                }
            }

            if ($actuallyUseQuery) {
                if ($expanded === '' && $joiner !== '&') {
                    $expanded = $value['value'];
                } else {
                    $expanded = \sprintf('%s=%s', $value['value'], $expanded);
                }
            }

            $replacements[] = $expanded;
        }

        $ret = \implode($joiner, $replacements);

        if ('' === $ret) {
            // Spec section 3.2.4 and 3.2.5
            if (false === $allUndefined && ('#' === $prefix || '.' === $prefix)) {
                return $prefix;
            }
        } else {
            if ('' !== $prefix) {
                return \sprintf('%s%s', $prefix, $ret);
            }
        }

        return $ret;
    }

    /**
     * Parse an expression into parts
     *
     * @param string $expression Expression to parse
     *
     * @return array{operator:string, values:array<array{value:string, modifier:(''|'*'|':'), position?:int}>}
     */
    private static function parseExpression(string $expression): array
    {
        $result = [];

        if (isset(self::$operatorHash[$expression[0]])) {
            $result['operator'] = $expression[0];
            /** @var string */
            $expression = \substr($expression, 1);
        } else {
            $result['operator'] = '';
        }

        $result['values'] = [];
        foreach (\explode(',', $expression) as $value) {
            $value = \trim($value);
            $varspec = [];
            if ($colonPos = \strpos($value, ':')) {
                $varspec['value'] = (string) \substr($value, 0, $colonPos);
                $varspec['modifier'] = ':';
                $varspec['position'] = (int) \substr($value, $colonPos + 1);
            } elseif (\substr($value, -1) === '*') {
                $varspec['modifier'] = '*';
                $varspec['value'] = (string) \substr($value, 0, -1);
            } else {
                $varspec['value'] = $value;
                $varspec['modifier'] = '';
            }
            $result['values'][] = $varspec;
        }

        return $result;
    }

    /**
     * Determines if an array is associative.
     *
     * This makes the assumption that input arrays are sequences or hashes.
     * This assumption is a tradeoff for accuracy in favor of speed, but it
     * should work in almost every case where input is supplied for a URI
     * template.
     */
    private static function isAssoc(array $array): bool
    {
        return $array && \array_keys($array)[0] !== 0;
    }

    /**
     * Removes percent encoding on reserved characters (used with + and #
     * modifiers).
     */
    private static function decodeReserved(string $string): string
    {
        return \str_replace(self::$delimsPct, self::$delims, $string);
    }
}

.NET Framework

Project Request

ProjectC

Vehicle Maintenance

Movie Navigator

Customers Exchange

ATM

.NET Core

Mail Daemon

Custom

Buns of code

PHP

Mediabox

Loan Castle

Content Management

Laravel

Phone Check

Frontend

Forex Wall

Business projects

Certification Center

Amerikas Auto

Pet projects

Geolocation Assistant

Web Dynamics

Blackball

Good old times

DOS Clock

BrainOut

Airport Administrator

Atomizer

Mediabox