<?php
/**
 * Checks that the opening brace of a function is on the same line as the function declaration.
 *
 * @author    Greg Sherwood <gsherwood@squiz.net>
 * @copyright 2006-2023 Squiz Pty Ltd (ABN 77 084 670 600)
 * @copyright 2023 PHPCSStandards and contributors
 * @license   https://github.com/PHPCSStandards/PHP_CodeSniffer/blob/HEAD/licence.txt BSD Licence
 */

namespace PHP_CodeSniffer\Standards\Generic\Sniffs\Functions;

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

class OpeningFunctionBraceKernighanRitchieSniff implements Sniff
{

    /**
     * Should this sniff check function braces?
     *
     * @var boolean
     */
    public $checkFunctions = true;

    /**
     * Should this sniff check closure braces?
     *
     * @var boolean
     */
    public $checkClosures = false;


    /**
     * Registers the tokens that this sniff wants to listen for.
     *
     * @return array<int|string>
     */
    public function register()
    {
        return [
            T_FUNCTION,
            T_CLOSURE,
        ];
    }


    /**
     * 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, int $stackPtr)
    {
        $tokens = $phpcsFile->getTokens();

        if (isset($tokens[$stackPtr]['scope_opener']) === false) {
            return;
        }

        if (($tokens[$stackPtr]['code'] === T_FUNCTION
            && (bool) $this->checkFunctions === false)
            || ($tokens[$stackPtr]['code'] === T_CLOSURE
            && (bool) $this->checkClosures === false)
        ) {
            return;
        }

        $openingBrace = $tokens[$stackPtr]['scope_opener'];

        // Find the end of the function declaration.
        $prev = $phpcsFile->findPrevious(Tokens::EMPTY_TOKENS, ($openingBrace - 1), null, true);

        $functionLine = $tokens[$prev]['line'];
        $braceLine    = $tokens[$openingBrace]['line'];

        $lineDifference = ($braceLine - $functionLine);

        $metricType = 'Function';
        if ($tokens[$stackPtr]['code'] === T_CLOSURE) {
            $metricType = 'Closure';
        }

        if ($lineDifference > 0) {
            $phpcsFile->recordMetric($stackPtr, "$metricType opening brace placement", 'new line');
            $error = 'Opening brace should be on the same line as the declaration';
            $fix   = $phpcsFile->addFixableError($error, $openingBrace, 'BraceOnNewLine');
            if ($fix === true) {
                $phpcsFile->fixer->beginChangeset();
                $phpcsFile->fixer->addContent($prev, ' {');
                $phpcsFile->fixer->replaceToken($openingBrace, '');
                if ($tokens[($openingBrace + 1)]['code'] === T_WHITESPACE
                    && $tokens[($openingBrace + 2)]['line'] > $tokens[$openingBrace]['line']
                ) {
                    // Brace is followed by a new line, so remove it to ensure we don't
                    // leave behind a blank line at the top of the block.
                    $phpcsFile->fixer->replaceToken(($openingBrace + 1), '');

                    if ($tokens[($openingBrace - 1)]['code'] === T_WHITESPACE
                        && $tokens[($openingBrace - 1)]['line'] === $tokens[$openingBrace]['line']
                        && $tokens[($openingBrace - 2)]['line'] < $tokens[$openingBrace]['line']
                    ) {
                        // Brace is preceded by indent, so remove it to ensure we don't
                        // leave behind more indent than is required for the first line.
                        $phpcsFile->fixer->replaceToken(($openingBrace - 1), '');
                    }
                }

                $phpcsFile->fixer->endChangeset();
            }
        } else {
            $phpcsFile->recordMetric($stackPtr, "$metricType opening brace placement", 'same line');
        }

        $ignore   = Tokens::PHPCS_ANNOTATION_TOKENS;
        $ignore[] = T_WHITESPACE;
        $next     = $phpcsFile->findNext($ignore, ($openingBrace + 1), null, true);
        if ($tokens[$next]['line'] === $tokens[$openingBrace]['line']) {
            // Only throw this error when this is not an empty function.
            if ($next !== $tokens[$stackPtr]['scope_closer']
                && $tokens[$next]['code'] !== T_CLOSE_TAG
            ) {
                $error = 'Opening brace must be the last content on the line';
                $fix   = $phpcsFile->addFixableError($error, $openingBrace, 'ContentAfterBrace');
                if ($fix === true) {
                    $phpcsFile->fixer->addNewline($openingBrace);
                }
            }
        }

        // Only continue checking if the opening brace looks good.
        if ($lineDifference > 0) {
            return;
        }

        // Enforce a single space. Tabs not allowed.
        $spacing = $tokens[($openingBrace - 1)]['content'];
        if ($tokens[($openingBrace - 1)]['code'] !== T_WHITESPACE) {
            $length = 0;
        } elseif ($spacing === "\t") {
            // Tab without tab-width set, so no tab replacement has taken place.
            $length = '\t';
        } else {
            $length = strlen($spacing);
        }

        // If tab replacement is on, avoid confusing the user with a "expected 1 space, found 1"
        // message when the "1" found is actually a tab, not a space.
        if ($length === 1
            && isset($tokens[($openingBrace - 1)]['orig_content']) === true
            && $tokens[($openingBrace - 1)]['orig_content'] === "\t"
        ) {
            $length = '\t';
        }

        if ($length !== 1) {
            $error = 'Expected 1 space before opening brace; found %s';
            $data  = [$length];
            $fix   = $phpcsFile->addFixableError($error, $openingBrace, 'SpaceBeforeBrace', $data);
            if ($fix === true) {
                if ($length === 0) {
                    $phpcsFile->fixer->addContentBefore($openingBrace, ' ');
                } else {
                    $phpcsFile->fixer->replaceToken(($openingBrace - 1), ' ');
                }
            }
        }
    }
}
