<?php
/**
 * PHPCompatibility, an external standard for PHP_CodeSniffer.
 *
 * @package   PHPCompatibility
 * @copyright 2012-2019 PHPCompatibility Contributors
 * @license   https://opensource.org/licenses/LGPL-3.0 LGPL3
 * @link      https://github.com/PHPCompatibility/PHPCompatibility
 */

namespace PHPCompatibility\Sniffs\ParameterValues;

use PHPCompatibility\AbstractFunctionCallParameterSniff;
use PHP_CodeSniffer_File as File;

/**
 * Detect usage of non-cryptographic hashes.
 *
 * "The `hash_hmac()`, `hash_hmac_file()`, `hash_pbkdf2()`, and `hash_init()`
 * (with `HASH_HMAC`) functions no longer accept non-cryptographic hashes."
 *
 * PHP version 7.2
 *
 * @link https://www.php.net/manual/en/migration72.incompatible.php#migration72.incompatible.hash-functions
 *
 * @since 9.0.0
 */
class RemovedNonCryptoHashSniff extends AbstractFunctionCallParameterSniff {


	/**
	 * Functions to check for.
	 *
	 * @since 9.0.0
	 *
	 * @var array
	 */
	protected $targetFunctions = array(
		'hash_hmac'      => true,
		'hash_hmac_file' => true,
		'hash_init'      => true,
		'hash_pbkdf2'    => true,
	);

	/**
	 * List of the non-cryptographic hashes.
	 *
	 * @since 9.0.0
	 *
	 * @var array
	 */
	protected $disabledCryptos = array(
		'adler32' => true,
		'crc32'   => true,
		'crc32b'  => true,
		'fnv132'  => true,
		'fnv1a32' => true,
		'fnv164'  => true,
		'fnv1a64' => true,
		'joaat'   => true,
	);


	/**
	 * Do a version check to determine if this sniff needs to run at all.
	 *
	 * @since 9.0.0
	 *
	 * @return bool
	 */
	protected function bowOutEarly() {
		return ( $this->supportsAbove( '7.2' ) === false );
	}


	/**
	 * Process the parameters of a matched function.
	 *
	 * @since 9.0.0
	 *
	 * @param \PHP_CodeSniffer_File $phpcsFile    The file being scanned.
	 * @param int                   $stackPtr     The position of the current token in the stack.
	 * @param string                $functionName The token content (function name) which was matched.
	 * @param array                 $parameters   Array with information about the parameters.
	 *
	 * @return int|void Integer stack pointer to skip forward or void to continue
	 *                  normal file processing.
	 */
	public function processParameters( File $phpcsFile, $stackPtr, $functionName, $parameters ) {
		if ( isset( $parameters[1] ) === false ) {
			return;
		}

		$targetParam = $parameters[1];

		if ( isset( $this->disabledCryptos[ $this->stripQuotes( $targetParam['raw'] ) ] ) === false ) {
			return;
		}

		if ( strtolower( $functionName ) === 'hash_init'
			&& ( isset( $parameters[2] ) === false
			|| ( $parameters[2]['raw'] !== 'HASH_HMAC'
				&& $parameters[2]['raw'] !== (string) \HASH_HMAC ) )
		) {
			// For hash_init(), these hashes are only disabled with HASH_HMAC set.
			return;
		}

		$phpcsFile->addError(
			'Non-cryptographic hashes are no longer accepted by function %s() since PHP 7.2. Found: %s',
			$targetParam['start'],
			$this->stringToErrorCode( $functionName ),
			array(
				$functionName,
				$targetParam['raw'],
			)
		);
	}
}
