<?php

namespace Illuminate\Support;

use Closure;
use Illuminate\Support\Traits\Macroable;
use JsonException;
use League\CommonMark\Environment\Environment;
use League\CommonMark\Extension\GithubFlavoredMarkdownExtension;
use League\CommonMark\Extension\InlinesOnly\InlinesOnlyExtension;
use League\CommonMark\GithubFlavoredMarkdownConverter;
use League\CommonMark\MarkdownConverter;
use Ramsey\Uuid\Codec\TimestampFirstCombCodec;
use Ramsey\Uuid\Generator\CombGenerator;
use Ramsey\Uuid\Uuid;
use Ramsey\Uuid\UuidFactory;
use Symfony\Component\Uid\Ulid;
use Traversable;
use voku\helper\ASCII;

class Str
{
    use Macroable;

    /**
     * The cache of snake-cased words.
     *
     * @var array
     */
    protected static $snakeCache = [];

    /**
     * The cache of camel-cased words.
     *
     * @var array
     */
    protected static $camelCache = [];

    /**
     * The cache of studly-cased words.
     *
     * @var array
     */
    protected static $studlyCache = [];

    /**
     * The callback that should be used to generate UUIDs.
     *
     * @var callable|null
     */
    protected static $uuidFactory;

    /**
     * The callback that should be used to generate random strings.
     *
     * @var callable|null
     */
    protected static $randomStringFactory;

    /**
     * Get a new stringable object from the given string.
     *
     * @param  string  $string
     * @return \Illuminate\Support\Stringable
     */
    public static function of($string)
    {
        return new Stringable($string);
    }

    /**
     * Return the remainder of a string after the first occurrence of a given value.
     *
     * @param  string  $subject
     * @param  string  $search
     * @return string
     */
    public static function after($subject, $search)
    {
        return $search === '' ? $subject : array_reverse(explode($search, $subject, 2))[0];
    }

    /**
     * Return the remainder of a string after the last occurrence of a given value.
     *
     * @param  string  $subject
     * @param  string  $search
     * @return string
     */
    public static function afterLast($subject, $search)
    {
        if ($search === '') {
            return $subject;
        }

        $position = strrpos($subject, (string) $search);

        if ($position === false) {
            return $subject;
        }

        return substr($subject, $position + strlen($search));
    }

    /**
     * Transliterate a UTF-8 value to ASCII.
     *
     * @param  string  $value
     * @param  string  $language
     * @return string
     */
    public static function ascii($value, $language = 'en')
    {
        return ASCII::to_ascii((string) $value, $language);
    }

    /**
     * Transliterate a string to its closest ASCII representation.
     *
     * @param  string  $string
     * @param  string|null  $unknown
     * @param  bool|null  $strict
     * @return string
     */
    public static function transliterate($string, $unknown = '?', $strict = false)
    {
        return ASCII::to_transliterate($string, $unknown, $strict);
    }

    /**
     * Get the portion of a string before the first occurrence of a given value.
     *
     * @param  string  $subject
     * @param  string  $search
     * @return string
     */
    public static function before($subject, $search)
    {
        if ($search === '') {
            return $subject;
        }

        $result = strstr($subject, (string) $search, true);

        return $result === false ? $subject : $result;
    }

    /**
     * Get the portion of a string before the last occurrence of a given value.
     *
     * @param  string  $subject
     * @param  string  $search
     * @return string
     */
    public static function beforeLast($subject, $search)
    {
        if ($search === '') {
            return $subject;
        }

        $pos = mb_strrpos($subject, $search);

        if ($pos === false) {
            return $subject;
        }

        return static::substr($subject, 0, $pos);
    }

    /**
     * Get the portion of a string between two given values.
     *
     * @param  string  $subject
     * @param  string  $from
     * @param  string  $to
     * @return string
     */
    public static function between($subject, $from, $to)
    {
        if ($from === '' || $to === '') {
            return $subject;
        }

        return static::beforeLast(static::after($subject, $from), $to);
    }

    /**
     * Get the smallest possible portion of a string between two given values.
     *
     * @param  string  $subject
     * @param  string  $from
     * @param  string  $to
     * @return string
     */
    public static function betweenFirst($subject, $from, $to)
    {
        if ($from === '' || $to === '') {
            return $subject;
        }

        return static::before(static::after($subject, $from), $to);
    }

    /**
     * Convert a value to camel case.
     *
     * @param  string  $value
     * @return string
     */
    public static function camel($value)
    {
        if (isset(static::$camelCache[$value])) {
            return static::$camelCache[$value];
        }

        return static::$camelCache[$value] = lcfirst(static::studly($value));
    }

    /**
     * Determine if a given string contains a given substring.
     *
     * @param  string  $haystack
     * @param  string|iterable<string>  $needles
     * @param  bool  $ignoreCase
     * @return bool
     */
    public static function contains($haystack, $needles, $ignoreCase = false)
    {
        if ($ignoreCase) {
            $haystack = mb_strtolower($haystack);
        }

        if (! is_iterable($needles)) {
            $needles = (array) $needles;
        }

        foreach ($needles as $needle) {
            if ($ignoreCase) {
                $needle = mb_strtolower($needle);
            }

            if ($needle !== '' && str_contains($haystack, $needle)) {
                return true;
            }
        }

        return false;
    }

    /**
     * Determine if a given string contains all array values.
     *
     * @param  string  $haystack
     * @param  iterable<string>  $needles
     * @param  bool  $ignoreCase
     * @return bool
     */
    public static function containsAll($haystack, $needles, $ignoreCase = false)
    {
        foreach ($needles as $needle) {
            if (! static::contains($haystack, $needle, $ignoreCase)) {
                return false;
            }
        }

        return true;
    }

    /**
     * Determine if a given string ends with a given substring.
     *
     * @param  string  $haystack
     * @param  string|iterable<string>  $needles
     * @return bool
     */
    public static function endsWith($haystack, $needles)
    {
        if (! is_iterable($needles)) {
            $needles = (array) $needles;
        }

        foreach ($needles as $needle) {
            if ((string) $needle !== '' && str_ends_with($haystack, $needle)) {
                return true;
            }
        }

        return false;
    }

    /**
     * Extracts an excerpt from text that matches the first instance of a phrase.
     *
     * @param  string  $text
     * @param  string  $phrase
     * @param  array  $options
     * @return string|null
     */
    public static function excerpt($text, $phrase = '', $options = [])
    {
        $radius = $options['radius'] ?? 100;
        $omission = $options['omission'] ?? '...';

        preg_match('/^(.*?)('.preg_quote((string) $phrase).')(.*)$/iu', (string) $text, $matches);

        if (empty($matches)) {
            return null;
        }

        $start = ltrim($matches[1]);

        $start = str(mb_substr($start, max(mb_strlen($start, 'UTF-8') - $radius, 0), $radius, 'UTF-8'))->ltrim()->unless(
            fn ($startWithRadius) => $startWithRadius->exactly($start),
            fn ($startWithRadius) => $startWithRadius->prepend($omission),
        );

        $end = rtrim($matches[3]);

        $end = str(mb_substr($end, 0, $radius, 'UTF-8'))->rtrim()->unless(
            fn ($endWithRadius) => $endWithRadius->exactly($end),
            fn ($endWithRadius) => $endWithRadius->append($omission),
        );

        return $start->append($matches[2], $end)->toString();
    }

    /**
     * Cap a string with a single instance of a given value.
     *
     * @param  string  $value
     * @param  string  $cap
     * @return string
     */
    public static function finish($value, $cap)
    {
        $quoted = preg_quote($cap, '/');

        return preg_replace('/(?:'.$quoted.')+$/u', '', $value).$cap;
    }

    /**
     * Wrap the string with the given strings.
     *
     * @param  string  $value
     * @param  string  $before
     * @param  string|null  $after
     * @return string
     */
    public static function wrap($value, $before, $after = null)
    {
        return $before.$value.($after ??= $before);
    }

    /**
     * Determine if a given string matches a given pattern.
     *
     * @param  string|iterable<string>  $pattern
     * @param  string  $value
     * @return bool
     */
    public static function is($pattern, $value)
    {
        $value = (string) $value;

        if (! is_iterable($pattern)) {
            $pattern = [$pattern];
        }

        foreach ($pattern as $pattern) {
            $pattern = (string) $pattern;

            // If the given value is an exact match we can of course return true right
            // from the beginning. Otherwise, we will translate asterisks and do an
            // actual pattern match against the two strings to see if they match.
            if ($pattern === $value) {
                return true;
            }

            $pattern = preg_quote($pattern, '#');

            // Asterisks are translated into zero-or-more regular expression wildcards
            // to make it convenient to check if the strings starts with the given
            // pattern such as "library/*", making any string check convenient.
            $pattern = str_replace('\*', '.*', $pattern);

            if (preg_match('#^'.$pattern.'\z#u', $value) === 1) {
                return true;
            }
        }

        return false;
    }

    /**
     * Determine if a given string is 7 bit ASCII.
     *
     * @param  string  $value
     * @return bool
     */
    public static function isAscii($value)
    {
        return ASCII::is_ascii((string) $value);
    }

    /**
     * Determine if a given string is valid JSON.
     *
     * @param  string  $value
     * @return bool
     */
    public static function isJson($value)
    {
        if (! is_string($value)) {
            return false;
        }

        try {
            json_decode($value, true, 512, JSON_THROW_ON_ERROR);
        } catch (JsonException) {
            return false;
        }

        return true;
    }

    /**
     * Determine if a given string is a valid UUID.
     *
     * @param  string  $value
     * @return bool
     */
    public static function isUuid($value)
    {
        if (! is_string($value)) {
            return false;
        }

        return preg_match('/^[\da-f]{8}-[\da-f]{4}-[\da-f]{4}-[\da-f]{4}-[\da-f]{12}$/iD', $value) > 0;
    }

    /**
     * Determine if a given string is a valid ULID.
     *
     * @param  string  $value
     * @return bool
     */
    public static function isUlid($value)
    {
        if (! is_string($value)) {
            return false;
        }

        return Ulid::isValid($value);
    }

    /**
     * Convert a string to kebab case.
     *
     * @param  string  $value
     * @return string
     */
    public static function kebab($value)
    {
        return static::snake($value, '-');
    }

    /**
     * Return the length of the given string.
     *
     * @param  string  $value
     * @param  string|null  $encoding
     * @return int
     */
    public static function length($value, $encoding = null)
    {
        if ($encoding) {
            return mb_strlen($value, $encoding);
        }

        return mb_strlen($value);
    }

    /**
     * Limit the number of characters in a string.
     *
     * @param  string  $value
     * @param  int  $limit
     * @param  string  $end
     * @return string
     */
    public static function limit($value, $limit = 100, $end = '...')
    {
        if (mb_strwidth($value, 'UTF-8') <= $limit) {
            return $value;
        }

        return rtrim(mb_strimwidth($value, 0, $limit, '', 'UTF-8')).$end;
    }

    /**
     * Convert the given string to lower-case.
     *
     * @param  string  $value
     * @return string
     */
    public static function lower($value)
    {
        return mb_strtolower($value, 'UTF-8');
    }

    /**
     * Limit the number of words in a string.
     *
     * @param  string  $value
     * @param  int  $words
     * @param  string  $end
     * @return string
     */
    public static function words($value, $words = 100, $end = '...')
    {
        preg_match('/^\s*+(?:\S++\s*+){1,'.$words.'}/u', $value, $matches);

        if (! isset($matches[0]) || static::length($value) === static::length($matches[0])) {
            return $value;
        }

        return rtrim($matches[0]).$end;
    }

    /**
     * Converts GitHub flavored Markdown into HTML.
     *
     * @param  string  $string
     * @param  array  $options
     * @return string
     */
    public static function markdown($string, array $options = [])
    {
        $converter = new GithubFlavoredMarkdownConverter($options);

        return (string) $converter->convert($string);
    }

    /**
     * Converts inline Markdown into HTML.
     *
     * @param  string  $string
     * @param  array  $options
     * @return string
     */
    public static function inlineMarkdown($string, array $options = [])
    {
        $environment = new Environment($options);

        $environment->addExtension(new GithubFlavoredMarkdownExtension());
        $environment->addExtension(new InlinesOnlyExtension());

        $converter = new MarkdownConverter($environment);

        return (string) $converter->convert($string);
    }

    /**
     * Masks a portion of a string with a repeated character.
     *
     * @param  string  $string
     * @param  string  $character
     * @param  int  $index
     * @param  int|null  $length
     * @param  string  $encoding
     * @return string
     */
    public static function mask($string, $character, $index, $length = null, $encoding = 'UTF-8')
    {
        if ($character === '') {
            return $string;
        }

        $segment = mb_substr($string, $index, $length, $encoding);

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

        $strlen = mb_strlen($string, $encoding);
        $startIndex = $index;

        if ($index < 0) {
            $startIndex = $index < -$strlen ? 0 : $strlen + $index;
        }

        $start = mb_substr($string, 0, $startIndex, $encoding);
        $segmentLen = mb_strlen($segment, $encoding);
        $end = mb_substr($string, $startIndex + $segmentLen);

        return $start.str_repeat(mb_substr($character, 0, 1, $encoding), $segmentLen).$end;
    }

    /**
     * Get the string matching the given pattern.
     *
     * @param  string  $pattern
     * @param  string  $subject
     * @return string
     */
    public static function match($pattern, $subject)
    {
        preg_match($pattern, $subject, $matches);

        if (! $matches) {
            return '';
        }

        return $matches[1] ?? $matches[0];
    }

    /**
     * Get the string matching the given pattern.
     *
     * @param  string  $pattern
     * @param  string  $subject
     * @return \Illuminate\Support\Collection
     */
    public static function matchAll($pattern, $subject)
    {
        preg_match_all($pattern, $subject, $matches);

        if (empty($matches[0])) {
            return collect();
        }

        return collect($matches[1] ?? $matches[0]);
    }

    /**
     * Pad both sides of a string with another.
     *
     * @param  string  $value
     * @param  int  $length
     * @param  string  $pad
     * @return string
     */
    public static function padBoth($value, $length, $pad = ' ')
    {
        $short = max(0, $length - mb_strlen($value));
        $shortLeft = floor($short / 2);
        $shortRight = ceil($short / 2);

        return mb_substr(str_repeat($pad, $shortLeft), 0, $shortLeft).
               $value.
               mb_substr(str_repeat($pad, $shortRight), 0, $shortRight);
    }

    /**
     * Pad the left side of a string with another.
     *
     * @param  string  $value
     * @param  int  $length
     * @param  string  $pad
     * @return string
     */
    public static function padLeft($value, $length, $pad = ' ')
    {
        $short = max(0, $length - mb_strlen($value));

        return mb_substr(str_repeat($pad, $short), 0, $short).$value;
    }

    /**
     * Pad the right side of a string with another.
     *
     * @param  string  $value
     * @param  int  $length
     * @param  string  $pad
     * @return string
     */
    public static function padRight($value, $length, $pad = ' ')
    {
        $short = max(0, $length - mb_strlen($value));

        return $value.mb_substr(str_repeat($pad, $short), 0, $short);
    }

    /**
     * Parse a Class[@]method style callback into class and method.
     *
     * @param  string  $callback
     * @param  string|null  $default
     * @return array<int, string|null>
     */
    public static function parseCallback($callback, $default = null)
    {
        return static::contains($callback, '@') ? explode('@', $callback, 2) : [$callback, $default];
    }

    /**
     * Get the plural form of an English word.
     *
     * @param  string  $value
     * @param  int|array|\Countable  $count
     * @return string
     */
    public static function plural($value, $count = 2)
    {
        return Pluralizer::plural($value, $count);
    }

    /**
     * Pluralize the last word of an English, studly caps case string.
     *
     * @param  string  $value
     * @param  int|array|\Countable  $count
     * @return string
     */
    public static function pluralStudly($value, $count = 2)
    {
        $parts = preg_split('/(.)(?=[A-Z])/u', $value, -1, PREG_SPLIT_DELIM_CAPTURE);

        $lastWord = array_pop($parts);

        return implode('', $parts).self::plural($lastWord, $count);
    }

    /**
     * Generate a more truly "random" alpha-numeric string.
     *
     * @param  int  $length
     * @return string
     */
    public static function random($length = 16)
    {
        return (static::$randomStringFactory ?? function ($length) {
            $string = '';

            while (($len = strlen($string)) < $length) {
                $size = $length - $len;

                $bytes = random_bytes($size);

                $string .= substr(str_replace(['/', '+', '='], '', base64_encode($bytes)), 0, $size);
            }

            return $string;
        })($length);
    }

    /**
     * Set the callable that will be used to generate random strings.
     *
     * @param  callable|null  $factory
     * @return void
     */
    public static function createRandomStringsUsing(callable $factory = null)
    {
        static::$randomStringFactory = $factory;
    }

    /**
     * Set the sequence that will be used to generate random strings.
     *
     * @param  array  $sequence
     * @param  callable|null  $whenMissing
     * @return void
     */
    public static function createRandomStringsUsingSequence(array $sequence, $whenMissing = null)
    {
        $next = 0;

        $whenMissing ??= function ($length) use (&$next) {
            $factoryCache = static::$randomStringFactory;

            static::$randomStringFactory = null;

            $randomString = static::random($length);

            static::$randomStringFactory = $factoryCache;

            $next++;

            return $randomString;
        };

        static::createRandomStringsUsing(function ($length) use (&$next, $sequence, $whenMissing) {
            if (array_key_exists($next, $sequence)) {
                return $sequence[$next++];
            }

            return $whenMissing($length);
        });
    }

    /**
     * Indicate that random strings should be created normally and not using a custom factory.
     *
     * @return void
     */
    public static function createRandomStringsNormally()
    {
        static::$randomStringFactory = null;
    }

    /**
     * Repeat the given string.
     *
     * @param  string  $string
     * @param  int  $times
     * @return string
     */
    public static function repeat(string $string, int $times)
    {
        return str_repeat($string, $times);
    }

    /**
     * Replace a given value in the string sequentially with an array.
     *
     * @param  string  $search
     * @param  iterable<string>  $replace
     * @param  string  $subject
     * @return string
     */
    public static function replaceArray($search, $replace, $subject)
    {
        if ($replace instanceof Traversable) {
            $replace = collect($replace)->all();
        }

        $segments = explode($search, $subject);

        $result = array_shift($segments);

        foreach ($segments as $segment) {
            $result .= (array_shift($replace) ?? $search).$segment;
        }

        return $result;
    }

    /**
     * Replace the given value in the given string.
     *
     * @param  string|iterable<string>  $search
     * @param  string|iterable<string>  $replace
     * @param  string|iterable<string>  $subject
     * @return string
     */
    public static function replace($search, $replace, $subject)
    {
        if ($search instanceof Traversable) {
            $search = collect($search)->all();
        }

        if ($replace instanceof Traversable) {
            $replace = collect($replace)->all();
        }

        if ($subject instanceof Traversable) {
            $subject = collect($subject)->all();
        }

        return str_replace($search, $replace, $subject);
    }

    /**
     * Replace the first occurrence of a given value in the string.
     *
     * @param  string  $search
     * @param  string  $replace
     * @param  string  $subject
     * @return string
     */
    public static function replaceFirst($search, $replace, $subject)
    {
        $search = (string) $search;

        if ($search === '') {
            return $subject;
        }

        $position = strpos($subject, $search);

        if ($position !== false) {
            return substr_replace($subject, $replace, $position, strlen($search));
        }

        return $subject;
    }

    /**
     * Replace the last occurrence of a given value in the string.
     *
     * @param  string  $search
     * @param  string  $replace
     * @param  string  $subject
     * @return string
     */
    public static function replaceLast($search, $replace, $subject)
    {
        if ($search === '') {
            return $subject;
        }

        $position = strrpos($subject, $search);

        if ($position !== false) {
            return substr_replace($subject, $replace, $position, strlen($search));
        }

        return $subject;
    }

    /**
     * Remove any occurrence of the given string in the subject.
     *
     * @param  string|iterable<string>  $search
     * @param  string  $subject
     * @param  bool  $caseSensitive
     * @return string
     */
    public static function remove($search, $subject, $caseSensitive = true)
    {
        if ($search instanceof Traversable) {
            $search = collect($search)->all();
        }

        $subject = $caseSensitive
                    ? str_replace($search, '', $subject)
                    : str_ireplace($search, '', $subject);

        return $subject;
    }

    /**
     * Reverse the given string.
     *
     * @param  string  $value
     * @return string
     */
    public static function reverse(string $value)
    {
        return implode(array_reverse(mb_str_split($value)));
    }

    /**
     * Begin a string with a single instance of a given value.
     *
     * @param  string  $value
     * @param  string  $prefix
     * @return string
     */
    public static function start($value, $prefix)
    {
        $quoted = preg_quote($prefix, '/');

        return $prefix.preg_replace('/^(?:'.$quoted.')+/u', '', $value);
    }

    /**
     * Convert the given string to upper-case.
     *
     * @param  string  $value
     * @return string
     */
    public static function upper($value)
    {
        return mb_strtoupper($value, 'UTF-8');
    }

    /**
     * Convert the given string to title case.
     *
     * @param  string  $value
     * @return string
     */
    public static function title($value)
    {
        return mb_convert_case($value, MB_CASE_TITLE, 'UTF-8');
    }

    /**
     * Convert the given string to title case for each word.
     *
     * @param  string  $value
     * @return string
     */
    public static function headline($value)
    {
        $parts = explode(' ', $value);

        $parts = count($parts) > 1
            ? array_map([static::class, 'title'], $parts)
            : array_map([static::class, 'title'], static::ucsplit(implode('_', $parts)));

        $collapsed = static::replace(['-', '_', ' '], '_', implode('_', $parts));

        return implode(' ', array_filter(explode('_', $collapsed)));
    }

    /**
     * Get the singular form of an English word.
     *
     * @param  string  $value
     * @return string
     */
    public static function singular($value)
    {
        return Pluralizer::singular($value);
    }

    /**
     * Generate a URL friendly "slug" from a given string.
     *
     * @param  string  $title
     * @param  string  $separator
     * @param  string|null  $language
     * @param  array<string, string>  $dictionary
     * @return string
     */
    public static function slug($title, $separator = '-', $language = 'en', $dictionary = ['@' => 'at'])
    {
        $title = $language ? static::ascii($title, $language) : $title;

        // Convert all dashes/underscores into separator
        $flip = $separator === '-' ? '_' : '-';

        $title = preg_replace('!['.preg_quote($flip).']+!u', $separator, $title);

        // Replace dictionary words
        foreach ($dictionary as $key => $value) {
            $dictionary[$key] = $separator.$value.$separator;
        }

        $title = str_replace(array_keys($dictionary), array_values($dictionary), $title);

        // Remove all characters that are not the separator, letters, numbers, or whitespace
        $title = preg_replace('![^'.preg_quote($separator).'\pL\pN\s]+!u', '', static::lower($title));

        // Replace all separator characters and whitespace by a single separator
        $title = preg_replace('!['.preg_quote($separator).'\s]+!u', $separator, $title);

        return trim($title, $separator);
    }

    /**
     * Convert a string to snake case.
     *
     * @param  string  $value
     * @param  string  $delimiter
     * @return string
     */
    public static function snake($value, $delimiter = '_')
    {
        $key = $value;

        if (isset(static::$snakeCache[$key][$delimiter])) {
            return static::$snakeCache[$key][$delimiter];
        }

        if (! ctype_lower($value)) {
            $value = preg_replace('/\s+/u', '', ucwords($value));

            $value = static::lower(preg_replace('/(.)(?=[A-Z])/u', '$1'.$delimiter, $value));
        }

        return static::$snakeCache[$key][$delimiter] = $value;
    }

    /**
     * Remove all "extra" blank space from the given string.
     *
     * @param  string  $value
     * @return string
     */
    public static function squish($value)
    {
        return preg_replace('~(\s|\x{3164})+~u', ' ', preg_replace('~^[\s﻿]+|[\s﻿]+$~u', '', $value));
    }

    /**
     * Determine if a given string starts with a given substring.
     *
     * @param  string  $haystack
     * @param  string|iterable<string>  $needles
     * @return bool
     */
    public static function startsWith($haystack, $needles)
    {
        if (! is_iterable($needles)) {
            $needles = [$needles];
        }

        foreach ($needles as $needle) {
            if ((string) $needle !== '' && str_starts_with($haystack, $needle)) {
                return true;
            }
        }

        return false;
    }

    /**
     * Convert a value to studly caps case.
     *
     * @param  string  $value
     * @return string
     */
    public static function studly($value)
    {
        $key = $value;

        if (isset(static::$studlyCache[$key])) {
            return static::$studlyCache[$key];
        }

        $words = explode(' ', static::replace(['-', '_'], ' ', $value));

        $studlyWords = array_map(fn ($word) => static::ucfirst($word), $words);

        return static::$studlyCache[$key] = implode($studlyWords);
    }

    /**
     * Returns the portion of the string specified by the start and length parameters.
     *
     * @param  string  $string
     * @param  int  $start
     * @param  int|null  $length
     * @return string
     */
    public static function substr($string, $start, $length = null)
    {
        return mb_substr($string, $start, $length, 'UTF-8');
    }

    /**
     * Returns the number of substring occurrences.
     *
     * @param  string  $haystack
     * @param  string  $needle
     * @param  int  $offset
     * @param  int|null  $length
     * @return int
     */
    public static function substrCount($haystack, $needle, $offset = 0, $length = null)
    {
        if (! is_null($length)) {
            return substr_count($haystack, $needle, $offset, $length);
        }

        return substr_count($haystack, $needle, $offset);
    }

    /**
     * Replace text within a portion of a string.
     *
     * @param  string|string[]  $string
     * @param  string|string[]  $replace
     * @param  int|int[]  $offset
     * @param  int|int[]|null  $length
     * @return string|string[]
     */
    public static function substrReplace($string, $replace, $offset = 0, $length = null)
    {
        if ($length === null) {
            $length = strlen($string);
        }

        return substr_replace($string, $replace, $offset, $length);
    }

    /**
     * Swap multiple keywords in a string with other keywords.
     *
     * @param  array  $map
     * @param  string  $subject
     * @return string
     */
    public static function swap(array $map, $subject)
    {
        return strtr($subject, $map);
    }

    /**
     * Make a string's first character lowercase.
     *
     * @param  string  $string
     * @return string
     */
    public static function lcfirst($string)
    {
        return static::lower(static::substr($string, 0, 1)).static::substr($string, 1);
    }

    /**
     * Make a string's first character uppercase.
     *
     * @param  string  $string
     * @return string
     */
    public static function ucfirst($string)
    {
        return static::upper(static::substr($string, 0, 1)).static::substr($string, 1);
    }

    /**
     * Split a string into pieces by uppercase characters.
     *
     * @param  string  $string
     * @return string[]
     */
    public static function ucsplit($string)
    {
        return preg_split('/(?=\p{Lu})/u', $string, -1, PREG_SPLIT_NO_EMPTY);
    }

    /**
     * Get the number of words a string contains.
     *
     * @param  string  $string
     * @param  string|null  $characters
     * @return int
     */
    public static function wordCount($string, $characters = null)
    {
        return str_word_count($string, 0, $characters);
    }

    /**
     * Generate a UUID (version 4).
     *
     * @return \Ramsey\Uuid\UuidInterface
     */
    public static function uuid()
    {
        return static::$uuidFactory
                    ? call_user_func(static::$uuidFactory)
                    : Uuid::uuid4();
    }

    /**
     * Generate a time-ordered UUID (version 4).
     *
     * @return \Ramsey\Uuid\UuidInterface
     */
    public static function orderedUuid()
    {
        if (static::$uuidFactory) {
            return call_user_func(static::$uuidFactory);
        }

        $factory = new UuidFactory;

        $factory->setRandomGenerator(new CombGenerator(
            $factory->getRandomGenerator(),
            $factory->getNumberConverter()
        ));

        $factory->setCodec(new TimestampFirstCombCodec(
            $factory->getUuidBuilder()
        ));

        return $factory->uuid4();
    }

    /**
     * Set the callable that will be used to generate UUIDs.
     *
     * @param  callable|null  $factory
     * @return void
     */
    public static function createUuidsUsing(callable $factory = null)
    {
        static::$uuidFactory = $factory;
    }

    /**
     * Set the sequence that will be used to generate UUIDs.
     *
     * @param  array  $sequence
     * @param  callable|null  $whenMissing
     * @return void
     */
    public static function createUuidsUsingSequence(array $sequence, $whenMissing = null)
    {
        $next = 0;

        $whenMissing ??= function () use (&$next) {
            $factoryCache = static::$uuidFactory;

            static::$uuidFactory = null;

            $uuid = static::uuid();

            static::$uuidFactory = $factoryCache;

            $next++;

            return $uuid;
        };

        static::createUuidsUsing(function () use (&$next, $sequence, $whenMissing) {
            if (array_key_exists($next, $sequence)) {
                return $sequence[$next++];
            }

            return $whenMissing();
        });
    }

    /**
     * Always return the same UUID when generating new UUIDs.
     *
     * @param  \Closure|null  $callback
     * @return \Ramsey\Uuid\UuidInterface
     */
    public static function freezeUuids(Closure $callback = null)
    {
        $uuid = Str::uuid();

        Str::createUuidsUsing(fn () => $uuid);

        if ($callback !== null) {
            try {
                $callback($uuid);
            } finally {
                Str::createUuidsNormally();
            }
        }

        return $uuid;
    }

    /**
     * Indicate that UUIDs should be created normally and not using a custom factory.
     *
     * @return void
     */
    public static function createUuidsNormally()
    {
        static::$uuidFactory = null;
    }

    /**
     * Generate a ULID.
     *
     * @return \Symfony\Component\Uid\Ulid
     */
    public static function ulid()
    {
        return new Ulid();
    }

    /**
     * Remove all strings from the casing caches.
     *
     * @return void
     */
    public static function flushCache()
    {
        static::$snakeCache = [];
        static::$camelCache = [];
        static::$studlyCache = [];
    }
}
