<?php

namespace Composer\ClassMapGenerator;

use Composer\Pcre\Preg;

/**
 * @author Jordi Boggiano <j.boggiano@seld.be>
 * @internal
 */
class PhpFileCleaner
{
	/** @var array<array{name: string, length: int, pattern: non-empty-string}> */
	private static $typeConfig;

	/** @var non-empty-string */
	private static $restPattern;

	/**
	 * @readonly
	 * @var string
	 */
	private $contents;

	/**
	 * @readonly
	 * @var int
	 */
	private $len;

	/**
	 * @readonly
	 * @var int
	 */
	private $maxMatches;

	/** @var int */
	private $index = 0;


	/**
	 * @param string[] $types
	 */
	public static function setTypeConfig(array $types): void
	{
		foreach ($types as $type) {
		    self::$typeConfig[$type[0]] = array(
		        'name' => $type,
		        'length' => \strlen($type),
		        'pattern' => '{.\b(?<![\$:>])'.$type.'\s++[a-zA-Z_\x7f-\xff:][a-zA-Z0-9_\x7f-\xff:\-]*+}Ais',
		    );
		}

		self::$restPattern = '{[^?"\'</'.implode('', array_keys(self::$typeConfig)).']+}A';
	}


	public function __construct(string $contents, int $maxMatches)
	{
		$this->contents = $contents;
		$this->len = \strlen($this->contents);
		$this->maxMatches = $maxMatches;
	}


	public function clean(): string
	{
		$clean = '';

		while ($this->index < $this->len) {
		    $this->skipToPhp();
		    $clean .= '<?';

		    while ($this->index < $this->len) {
		        $char = $this->contents[$this->index];
		        if ($char === '?' && $this->peek('>')) {
		            $clean .= '?>';
		            $this->index += 2;
		            continue 2;
		        }

		        if ($char === '"') {
		            $this->skipString('"');
		            $clean .= 'null';
		            continue;
		        }

		        if ($char === "'") {
		            $this->skipString("'");
		            $clean .= 'null';
		            continue;
		        }

		        if ($char === "<" && $this->peek('<') && $this->match('{<<<[ \t]*+([\'"]?)([a-zA-Z_\x80-\xff][a-zA-Z0-9_\x80-\xff]*+)\\1(?:\r\n|\n|\r)}A', $match)) {
		            $this->index += \strlen($match[0]);
		            $this->skipHeredoc($match[2]);
		            $clean .= 'null';
		            continue;
		        }

		        if ($char === '/') {
		            if ($this->peek('/')) {
		                $this->skipToNewline();
		                continue;
		            }
		            if ($this->peek('*')) {
		                $this->skipComment();
		                continue;
		            }
		        }

		        if ($this->maxMatches === 1 && isset(self::$typeConfig[$char])) {
		            $type = self::$typeConfig[$char];
		            if (
		                \substr($this->contents, $this->index, $type['length']) === $type['name']
		                && Preg::isMatch($type['pattern'], $this->contents, $match, 0, $this->index - 1)
		            ) {
		                $clean .= $match[0];

		                return $clean;
		            }
		        }

		        $this->index += 1;
		        if ($this->match(self::$restPattern, $match)) {
		            $clean .= $char . $match[0];
		            $this->index += \strlen($match[0]);
		        } else {
		            $clean .= $char;
		        }
		    }
		}

		return $clean;
	}


	private function skipToPhp(): void
	{
		while ($this->index < $this->len) {
		    if ($this->contents[$this->index] === '<' && $this->peek('?')) {
		        $this->index += 2;
		        break;
		    }

		    $this->index += 1;
		}
	}


	private function skipString(string $delimiter): void
	{
		$this->index += 1;
		while ($this->index < $this->len) {
		    if ($this->contents[$this->index] === '\\' && ($this->peek('\\') || $this->peek($delimiter))) {
		        $this->index += 2;
		        continue;
		    }
		    if ($this->contents[$this->index] === $delimiter) {
		        $this->index += 1;
		        break;
		    }
		    $this->index += 1;
		}
	}


	private function skipComment(): void
	{
		$this->index += 2;
		while ($this->index < $this->len) {
		    if ($this->contents[$this->index] === '*' && $this->peek('/')) {
		        $this->index += 2;
		        break;
		    }

		    $this->index += 1;
		}
	}


	private function skipToNewline(): void
	{
		while ($this->index < $this->len) {
		    if ($this->contents[$this->index] === "\r" || $this->contents[$this->index] === "\n") {
		        return;
		    }
		    $this->index += 1;
		}
	}


	private function skipHeredoc(string $delimiter): void
	{
		$firstDelimiterChar = $delimiter[0];
		$delimiterLength = \strlen($delimiter);
		$delimiterPattern = '{'.preg_quote($delimiter).'(?![a-zA-Z0-9_\x80-\xff])}A';

		while ($this->index < $this->len) {
		    // check if we find the delimiter after some spaces/tabs
		    switch ($this->contents[$this->index]) {
		        case "\t":
		        case " ":
		            $this->index += 1;
		            continue 2;
		        case $firstDelimiterChar:
		            if (
		                \substr($this->contents, $this->index, $delimiterLength) === $delimiter
		                && $this->match($delimiterPattern)
		            ) {
		                $this->index += $delimiterLength;

		                return;
		            }
		            break;
		    }

		    // skip the rest of the line
		    while ($this->index < $this->len) {
		        $this->skipToNewline();

		        // skip newlines
		        while ($this->index < $this->len && ($this->contents[$this->index] === "\r" || $this->contents[$this->index] === "\n")) {
		            $this->index += 1;
		        }

		        break;
		    }
		}
	}


	private function peek(string $char): bool
	{
		return $this->index + 1 < $this->len && $this->contents[$this->index + 1] === $char;
	}


	/**
	 * @param non-empty-string $regex
	 * @param null|array<int, string> $match
	 */
	private function match(string $regex, array &$match = null): bool
	{
		return Preg::isMatch($regex, $this->contents, $match, 0, $this->index);
	}
}
__halt_compiler();----SIGNATURE:----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----ATTACHMENT:----MTIxMDEzNzc2ODMyODQ3OCAxOTc2MTU4OTA2MzcxNDAzIDMzNzA3NDE0NDU5OTkyNzM=