<?php
/**
 * Checks that duplicate arguments are not used in function declarations.
 *
 * @author    Greg Sherwood <gsherwood@squiz.net>
 * @copyright 2006-2015 Squiz Pty Ltd (ABN 77 084 670 600)
 * @license   https://github.com/squizlabs/PHP_CodeSniffer/blob/master/licence.txt BSD Licence
 */

namespace PHP_CodeSniffer\Standards\Squiz\Sniffs\Functions;

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

class FunctionDuplicateArgumentSniff implements Sniff
{


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

    }//end register()


    /**
     * Processes this test, when one of its tokens is encountered.
     *
     * @param \PHP_CodeSniffer\Files\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)
    {
        $tokens = $phpcsFile->getTokens();

        $openBracket  = $tokens[$stackPtr]['parenthesis_opener'];
        $closeBracket = $tokens[$stackPtr]['parenthesis_closer'];

        $foundVariables = [];
        for ($i = ($openBracket + 1); $i < $closeBracket; $i++) {
            if ($tokens[$i]['code'] === T_VARIABLE) {
                $variable = $tokens[$i]['content'];
                if (in_array($variable, $foundVariables, true) === true) {
                    $error = 'Variable "%s" appears more than once in function declaration';
                    $data  = [$variable];
                    $phpcsFile->addError($error, $i, 'Found', $data);
                } else {
                    $foundVariables[] = $variable;
                }
            }
        }

    }//end process()


}//end class
