<?php
/**
 * Checks that plus is not used for string concat
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 */

namespace MediaWiki\Sniffs\Usage;

use PHP_CodeSniffer\Files\File;
use PHP_CodeSniffer\Sniffs\Sniff;
use PHP_CodeSniffer\Util\Tokens;

class PlusStringConcatSniff implements Sniff {

	/**
	 * Returns an array of tokens this test wants to listen for.
	 *
	 * @return array
	 */
	public function register(): array {
		return [ T_PLUS, T_PLUS_EQUAL ];
	}

	/**
	 * Processes this sniff, when one of its tokens is encountered.
	 *
	 * @param 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 ) {
		$prev = $phpcsFile->findPrevious( Tokens::$emptyTokens, $stackPtr - 1, null, true );
		$next = $phpcsFile->findNext( Tokens::$emptyTokens, $stackPtr + 1, null, true );
		if ( $prev === false || $next === false ) {
			// Live coding
			return;
		}
		$tokens = $phpcsFile->getTokens();

		// The token + should not have a string before or after it
		if ( isset( Tokens::$stringTokens[$tokens[$prev]['code']] )
			|| isset( Tokens::$stringTokens[$tokens[$next]['code']] )
		) {
			$phpcsFile->addError(
				'Use "%s" for string concat',
				$stackPtr,
				'Found',
				[ $tokens[$stackPtr]['code'] === T_PLUS ? '.' : '.=' ]
			);
		}
	}

}