<?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\Syntax;

use PHPCompatibility\Sniff;
use PHP_CodeSniffer_File as File;
use PHP_CodeSniffer_Tokens as Tokens;

/**
 * Detect dynamic access to static methods and properties, as well as class constants.
 *
 * As of PHP 5.3, static properties and methods as well as class constants
 * can be accessed using a dynamic (variable) class name.
 *
 * PHP version 5.3
 *
 * @link https://www.php.net/manual/en/migration53.new-features.php
 *
 * @since 8.1.0
 * @since 9.0.0 Renamed from `DynamicAccessToStaticSniff` to `NewDynamicAccessToStaticSniff`.
 */
class NewDynamicAccessToStaticSniff extends Sniff {


	/**
	 * Returns an array of tokens this test wants to listen for.
	 *
	 * @since 8.1.0
	 *
	 * @return array
	 */
	public function register() {
		return array(
			\T_DOUBLE_COLON,
		);
	}

	/**
	 * Processes this test, when one of its tokens is encountered.
	 *
	 * @since 8.1.0
	 *
	 * @param \PHP_CodeSniffer_File $phpcsFile The file being scanned.
	 * @param int                   $stackPtr  The position of the current token in the
	 *                                         stack passed in $tokens.
	 *
	 * @return void
	 */
	public function process( File $phpcsFile, $stackPtr ) {
		if ( $this->supportsBelow( '5.2' ) === false ) {
			return;
		}

		$tokens       = $phpcsFile->getTokens();
		$prevNonEmpty = $phpcsFile->findPrevious( Tokens::$emptyTokens, ( $stackPtr - 1 ), null, true );

		// Disregard `static::` as well. Late static binding is reported by another sniff.
		if ( $tokens[ $prevNonEmpty ]['code'] === \T_SELF
			|| $tokens[ $prevNonEmpty ]['code'] === \T_PARENT
			|| $tokens[ $prevNonEmpty ]['code'] === \T_STATIC
		) {
			return;
		}

		if ( $tokens[ $prevNonEmpty ]['code'] === \T_STRING ) {
			$prevPrevNonEmpty = $phpcsFile->findPrevious( Tokens::$emptyTokens, ( $prevNonEmpty - 1 ), null, true );

			if ( $tokens[ $prevPrevNonEmpty ]['code'] !== \T_OBJECT_OPERATOR ) {
				return;
			}
		}

		$phpcsFile->addError(
			'Static class properties and methods, as well as class constants, could not be accessed using a dynamic (variable) classname in PHP 5.2 or earlier.',
			$stackPtr,
			'Found'
		);
	}
}
