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

namespace Symfony\Component\String;

use Symfony\Component\String\Exception\ExceptionInterface;
use Symfony\Component\String\Exception\InvalidArgumentException;
use Symfony\Component\String\Exception\RuntimeException;

/**
 * Represents a string of abstract characters.
 *
 * Unicode defines 3 types of &quot;characters&quot; (bytes, code points and grapheme clusters).
 * This class is the abstract type to use as a type-hint when the logic you want to
 * implement doesn't care about the exact variant it deals with.
 *
 * @author Nicolas Grekas &lt;p@tchwork.com&gt;
 * @author Hugo Hamon &lt;hugohamon@neuf.fr&gt;
 *
 * @throws ExceptionInterface
 */
abstract class AbstractString implements \Stringable, \JsonSerializable
{
    public const PREG_PATTERN_ORDER = \PREG_PATTERN_ORDER;
    public const PREG_SET_ORDER = \PREG_SET_ORDER;
    public const PREG_OFFSET_CAPTURE = \PREG_OFFSET_CAPTURE;
    public const PREG_UNMATCHED_AS_NULL = \PREG_UNMATCHED_AS_NULL;

    public const PREG_SPLIT = 0;
    public const PREG_SPLIT_NO_EMPTY = \PREG_SPLIT_NO_EMPTY;
    public const PREG_SPLIT_DELIM_CAPTURE = \PREG_SPLIT_DELIM_CAPTURE;
    public const PREG_SPLIT_OFFSET_CAPTURE = \PREG_SPLIT_OFFSET_CAPTURE;

    protected $string = '';
    protected $ignoreCase = false;

    abstract public function __construct(string $string = '');

    /**
     * Unwraps instances of AbstractString back to strings.
     *
     * @return string[]|array
     */
    public static function unwrap(array $values): array
    {
        foreach ($values as $k =&gt; $v) {
            if ($v instanceof self) {
                $values[$k] = $v-&gt;__toString();
            } elseif (\is_array($v) &amp;&amp; $values[$k] !== $v = static::unwrap($v)) {
                $values[$k] = $v;
            }
        }

        return $values;
    }

    /**
     * Wraps (and normalizes) strings in instances of AbstractString.
     *
     * @return static[]|array
     */
    public static function wrap(array $values): array
    {
        $i = 0;
        $keys = null;

        foreach ($values as $k =&gt; $v) {
            if (\is_string($k) &amp;&amp; '' !== $k &amp;&amp; $k !== $j = (string) new static($k)) {
                $keys ??= array_keys($values);
                $keys[$i] = $j;
            }

            if (\is_string($v)) {
                $values[$k] = new static($v);
            } elseif (\is_array($v) &amp;&amp; $values[$k] !== $v = static::wrap($v)) {
                $values[$k] = $v;
            }

            ++$i;
        }

        return null !== $keys ? array_combine($keys, $values) : $values;
    }

    /**
     * @param string|string[] $needle
     */
    public function after(string|iterable $needle, bool $includeNeedle = false, int $offset = 0): static
    {
        $str = clone $this;
        $i = \PHP_INT_MAX;

        if (\is_string($needle)) {
            $needle = [$needle];
        }

        foreach ($needle as $n) {
            $n = (string) $n;
            $j = $this-&gt;indexOf($n, $offset);

            if (null !== $j &amp;&amp; $j &lt; $i) {
                $i = $j;
                $str-&gt;string = $n;
            }
        }

        if (\PHP_INT_MAX === $i) {
            return $str;
        }

        if (!$includeNeedle) {
            $i += $str-&gt;length();
        }

        return $this-&gt;slice($i);
    }

    /**
     * @param string|string[] $needle
     */
    public function afterLast(string|iterable $needle, bool $includeNeedle = false, int $offset = 0): static
    {
        $str = clone $this;
        $i = null;

        if (\is_string($needle)) {
            $needle = [$needle];
        }

        foreach ($needle as $n) {
            $n = (string) $n;
            $j = $this-&gt;indexOfLast($n, $offset);

            if (null !== $j &amp;&amp; $j &gt;= $i) {
                $i = $offset = $j;
                $str-&gt;string = $n;
            }
        }

        if (null === $i) {
            return $str;
        }

        if (!$includeNeedle) {
            $i += $str-&gt;length();
        }

        return $this-&gt;slice($i);
    }

    abstract public function append(string ...$suffix): static;

    /**
     * @param string|string[] $needle
     */
    public function before(string|iterable $needle, bool $includeNeedle = false, int $offset = 0): static
    {
        $str = clone $this;
        $i = \PHP_INT_MAX;

        if (\is_string($needle)) {
            $needle = [$needle];
        }

        foreach ($needle as $n) {
            $n = (string) $n;
            $j = $this-&gt;indexOf($n, $offset);

            if (null !== $j &amp;&amp; $j &lt; $i) {
                $i = $j;
                $str-&gt;string = $n;
            }
        }

        if (\PHP_INT_MAX === $i) {
            return $str;
        }

        if ($includeNeedle) {
            $i += $str-&gt;length();
        }

        return $this-&gt;slice(0, $i);
    }

    /**
     * @param string|string[] $needle
     */
    public function beforeLast(string|iterable $needle, bool $includeNeedle = false, int $offset = 0): static
    {
        $str = clone $this;
        $i = null;

        if (\is_string($needle)) {
            $needle = [$needle];
        }

        foreach ($needle as $n) {
            $n = (string) $n;
            $j = $this-&gt;indexOfLast($n, $offset);

            if (null !== $j &amp;&amp; $j &gt;= $i) {
                $i = $offset = $j;
                $str-&gt;string = $n;
            }
        }

        if (null === $i) {
            return $str;
        }

        if ($includeNeedle) {
            $i += $str-&gt;length();
        }

        return $this-&gt;slice(0, $i);
    }

    /**
     * @return int[]
     */
    public function bytesAt(int $offset): array
    {
        $str = $this-&gt;slice($offset, 1);

        return '' === $str-&gt;string ? [] : array_values(unpack('C*', $str-&gt;string));
    }

    abstract public function camel(): static;

    /**
     * @return static[]
     */
    abstract public function chunk(int $length = 1): array;

    public function collapseWhitespace(): static
    {
        $str = clone $this;
        $str-&gt;string = trim(preg_replace(&quot;/(?:[ \n\r\t\x0C]{2,}+|[\n\r\t\x0C])/&quot;, ' ', $str-&gt;string), &quot; \n\r\t\x0C&quot;);

        return $str;
    }

    /**
     * @param string|string[] $needle
     */
    public function containsAny(string|iterable $needle): bool
    {
        return null !== $this-&gt;indexOf($needle);
    }

    /**
     * @param string|string[] $suffix
     */
    public function endsWith(string|iterable $suffix): bool
    {
        if (\is_string($suffix)) {
            throw new \TypeError(sprintf('Method &quot;%s()&quot; must be overridden by class &quot;%s&quot; to deal with non-iterable values.', __FUNCTION__, static::class));
        }

        foreach ($suffix as $s) {
            if ($this-&gt;endsWith((string) $s)) {
                return true;
            }
        }

        return false;
    }

    public function ensureEnd(string $suffix): static
    {
        if (!$this-&gt;endsWith($suffix)) {
            return $this-&gt;append($suffix);
        }

        $suffix = preg_quote($suffix);
        $regex = '{('.$suffix.')(?:'.$suffix.')++$}D';

        return $this-&gt;replaceMatches($regex.($this-&gt;ignoreCase ? 'i' : ''), '$1');
    }

    public function ensureStart(string $prefix): static
    {
        $prefix = new static($prefix);

        if (!$this-&gt;startsWith($prefix)) {
            return $this-&gt;prepend($prefix);
        }

        $str = clone $this;
        $i = $prefixLen = $prefix-&gt;length();

        while ($this-&gt;indexOf($prefix, $i) === $i) {
            $str = $str-&gt;slice($prefixLen);
            $i += $prefixLen;
        }

        return $str;
    }

    /**
     * @param string|string[] $string
     */
    public function equalsTo(string|iterable $string): bool
    {
        if (\is_string($string)) {
            throw new \TypeError(sprintf('Method &quot;%s()&quot; must be overridden by class &quot;%s&quot; to deal with non-iterable values.', __FUNCTION__, static::class));
        }

        foreach ($string as $s) {
            if ($this-&gt;equalsTo((string) $s)) {
                return true;
            }
        }

        return false;
    }

    abstract public function folded(): static;

    public function ignoreCase(): static
    {
        $str = clone $this;
        $str-&gt;ignoreCase = true;

        return $str;
    }

    /**
     * @param string|string[] $needle
     */
    public function indexOf(string|iterable $needle, int $offset = 0): ?int
    {
        if (\is_string($needle)) {
            throw new \TypeError(sprintf('Method &quot;%s()&quot; must be overridden by class &quot;%s&quot; to deal with non-iterable values.', __FUNCTION__, static::class));
        }

        $i = \PHP_INT_MAX;

        foreach ($needle as $n) {
            $j = $this-&gt;indexOf((string) $n, $offset);

            if (null !== $j &amp;&amp; $j &lt; $i) {
                $i = $j;
            }
        }

        return \PHP_INT_MAX === $i ? null : $i;
    }

    /**
     * @param string|string[] $needle
     */
    public function indexOfLast(string|iterable $needle, int $offset = 0): ?int
    {
        if (\is_string($needle)) {
            throw new \TypeError(sprintf('Method &quot;%s()&quot; must be overridden by class &quot;%s&quot; to deal with non-iterable values.', __FUNCTION__, static::class));
        }

        $i = null;

        foreach ($needle as $n) {
            $j = $this-&gt;indexOfLast((string) $n, $offset);

            if (null !== $j &amp;&amp; $j &gt;= $i) {
                $i = $offset = $j;
            }
        }

        return $i;
    }

    public function isEmpty(): bool
    {
        return '' === $this-&gt;string;
    }

    abstract public function join(array $strings, string $lastGlue = null): static;

    public function jsonSerialize(): string
    {
        return $this-&gt;string;
    }

    abstract public function length(): int;

    abstract public function lower(): static;

    /**
     * Matches the string using a regular expression.
     *
     * Pass PREG_PATTERN_ORDER or PREG_SET_ORDER as $flags to get all occurrences matching the regular expression.
     *
     * @return array All matches in a multi-dimensional array ordered according to flags
     */
    abstract public function match(string $regexp, int $flags = 0, int $offset = 0): array;

    abstract public function padBoth(int $length, string $padStr = ' '): static;

    abstract public function padEnd(int $length, string $padStr = ' '): static;

    abstract public function padStart(int $length, string $padStr = ' '): static;

    abstract public function prepend(string ...$prefix): static;

    public function repeat(int $multiplier): static
    {
        if (0 &gt; $multiplier) {
            throw new InvalidArgumentException(sprintf('Multiplier must be positive, %d given.', $multiplier));
        }

        $str = clone $this;
        $str-&gt;string = str_repeat($str-&gt;string, $multiplier);

        return $str;
    }

    abstract public function replace(string $from, string $to): static;

    abstract public function replaceMatches(string $fromRegexp, string|callable $to): static;

    abstract public function reverse(): static;

    abstract public function slice(int $start = 0, int $length = null): static;

    abstract public function snake(): static;

    abstract public function splice(string $replacement, int $start = 0, int $length = null): static;

    /**
     * @return static[]
     */
    public function split(string $delimiter, int $limit = null, int $flags = null): array
    {
        if (null === $flags) {
            throw new \TypeError('Split behavior when $flags is null must be implemented by child classes.');
        }

        if ($this-&gt;ignoreCase) {
            $delimiter .= 'i';
        }

        set_error_handler(static function ($t, $m) { throw new InvalidArgumentException($m); });

        try {
            if (false === $chunks = preg_split($delimiter, $this-&gt;string, $limit, $flags)) {
                throw new RuntimeException('Splitting failed with error: '.preg_last_error_msg());
            }
        } finally {
            restore_error_handler();
        }

        $str = clone $this;

        if (self::PREG_SPLIT_OFFSET_CAPTURE &amp; $flags) {
            foreach ($chunks as &amp;$chunk) {
                $str-&gt;string = $chunk[0];
                $chunk[0] = clone $str;
            }
        } else {
            foreach ($chunks as &amp;$chunk) {
                $str-&gt;string = $chunk;
                $chunk = clone $str;
            }
        }

        return $chunks;
    }

    /**
     * @param string|string[] $prefix
     */
    public function startsWith(string|iterable $prefix): bool
    {
        if (\is_string($prefix)) {
            throw new \TypeError(sprintf('Method &quot;%s()&quot; must be overridden by class &quot;%s&quot; to deal with non-iterable values.', __FUNCTION__, static::class));
        }

        foreach ($prefix as $prefix) {
            if ($this-&gt;startsWith((string) $prefix)) {
                return true;
            }
        }

        return false;
    }

    abstract public function title(bool $allWords = false): static;

    public function toByteString(string $toEncoding = null): ByteString
    {
        $b = new ByteString();

        $toEncoding = \in_array($toEncoding, ['utf8', 'utf-8', 'UTF8'], true) ? 'UTF-8' : $toEncoding;

        if (null === $toEncoding || $toEncoding === $fromEncoding = $this instanceof AbstractUnicodeString || preg_match('//u', $b-&gt;string) ? 'UTF-8' : 'Windows-1252') {
            $b-&gt;string = $this-&gt;string;

            return $b;
        }

        set_error_handler(static function ($t, $m) { throw new InvalidArgumentException($m); });

        try {
            try {
                $b-&gt;string = mb_convert_encoding($this-&gt;string, $toEncoding, 'UTF-8');
            } catch (InvalidArgumentException $e) {
                if (!\function_exists('iconv')) {
                    throw $e;
                }

                $b-&gt;string = iconv('UTF-8', $toEncoding, $this-&gt;string);
            }
        } finally {
            restore_error_handler();
        }

        return $b;
    }

    public function toCodePointString(): CodePointString
    {
        return new CodePointString($this-&gt;string);
    }

    public function toString(): string
    {
        return $this-&gt;string;
    }

    public function toUnicodeString(): UnicodeString
    {
        return new UnicodeString($this-&gt;string);
    }

    abstract public function trim(string $chars = &quot; \t\n\r\0\x0B\x0C\u{A0}\u{FEFF}&quot;): static;

    abstract public function trimEnd(string $chars = &quot; \t\n\r\0\x0B\x0C\u{A0}\u{FEFF}&quot;): static;

    /**
     * @param string|string[] $prefix
     */
    public function trimPrefix($prefix): static
    {
        if (\is_array($prefix) || $prefix instanceof \Traversable) { // don't use is_iterable(), it's slow
            foreach ($prefix as $s) {
                $t = $this-&gt;trimPrefix($s);

                if ($t-&gt;string !== $this-&gt;string) {
                    return $t;
                }
            }

            return clone $this;
        }

        $str = clone $this;

        if ($prefix instanceof self) {
            $prefix = $prefix-&gt;string;
        } else {
            $prefix = (string) $prefix;
        }

        if ('' !== $prefix &amp;&amp; \strlen($this-&gt;string) &gt;= \strlen($prefix) &amp;&amp; 0 === substr_compare($this-&gt;string, $prefix, 0, \strlen($prefix), $this-&gt;ignoreCase)) {
            $str-&gt;string = substr($this-&gt;string, \strlen($prefix));
        }

        return $str;
    }

    abstract public function trimStart(string $chars = &quot; \t\n\r\0\x0B\x0C\u{A0}\u{FEFF}&quot;): static;

    /**
     * @param string|string[] $suffix
     */
    public function trimSuffix($suffix): static
    {
        if (\is_array($suffix) || $suffix instanceof \Traversable) { // don't use is_iterable(), it's slow
            foreach ($suffix as $s) {
                $t = $this-&gt;trimSuffix($s);

                if ($t-&gt;string !== $this-&gt;string) {
                    return $t;
                }
            }

            return clone $this;
        }

        $str = clone $this;

        if ($suffix instanceof self) {
            $suffix = $suffix-&gt;string;
        } else {
            $suffix = (string) $suffix;
        }

        if ('' !== $suffix &amp;&amp; \strlen($this-&gt;string) &gt;= \strlen($suffix) &amp;&amp; 0 === substr_compare($this-&gt;string, $suffix, -\strlen($suffix), null, $this-&gt;ignoreCase)) {
            $str-&gt;string = substr($this-&gt;string, 0, -\strlen($suffix));
        }

        return $str;
    }

    public function truncate(int $length, string $ellipsis = '', bool $cut = true): static
    {
        $stringLength = $this-&gt;length();

        if ($stringLength &lt;= $length) {
            return clone $this;
        }

        $ellipsisLength = '' !== $ellipsis ? (new static($ellipsis))-&gt;length() : 0;

        if ($length &lt; $ellipsisLength) {
            $ellipsisLength = 0;
        }

        if (!$cut) {
            if (null === $length = $this-&gt;indexOf([' ', &quot;\r&quot;, &quot;\n&quot;, &quot;\t&quot;], ($length ?: 1) - 1)) {
                return clone $this;
            }

            $length += $ellipsisLength;
        }

        $str = $this-&gt;slice(0, $length - $ellipsisLength);

        return $ellipsisLength ? $str-&gt;trimEnd()-&gt;append($ellipsis) : $str;
    }

    abstract public function upper(): static;

    /**
     * Returns the printable length on a terminal.
     */
    abstract public function width(bool $ignoreAnsiDecoration = true): int;

    public function wordwrap(int $width = 75, string $break = &quot;\n&quot;, bool $cut = false): static
    {
        $lines = '' !== $break ? $this-&gt;split($break) : [clone $this];
        $chars = [];
        $mask = '';

        if (1 === \count($lines) &amp;&amp; '' === $lines[0]-&gt;string) {
            return $lines[0];
        }

        foreach ($lines as $i =&gt; $line) {
            if ($i) {
                $chars[] = $break;
                $mask .= '#';
            }

            foreach ($line-&gt;chunk() as $char) {
                $chars[] = $char-&gt;string;
                $mask .= ' ' === $char-&gt;string ? ' ' : '?';
            }
        }

        $string = '';
        $j = 0;
        $b = $i = -1;
        $mask = wordwrap($mask, $width, '#', $cut);

        while (false !== $b = strpos($mask, '#', $b + 1)) {
            for (++$i; $i &lt; $b; ++$i) {
                $string .= $chars[$j];
                unset($chars[$j++]);
            }

            if ($break === $chars[$j] || ' ' === $chars[$j]) {
                unset($chars[$j++]);
            }

            $string .= $break;
        }

        $str = clone $this;
        $str-&gt;string = $string.implode('', $chars);

        return $str;
    }

    public function __sleep(): array
    {
        return ['string'];
    }

    public function __clone()
    {
        $this-&gt;ignoreCase = false;
    }

    public function __toString(): string
    {
        return $this-&gt;string;
    }
}
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