class Comment

class Comment {
    
    /**
     * Creates an array of tokens when given some PHP code.
     *
     * Starts by using token_get_all() but does a lot of extra processing
     * to insert information about the context of the token.
     *
     * @param string $string   The string to tokenize.
     * @param string $eolChar  The EOL character to use for splitting strings.
     * @param int    $stackPtr The position of the first token in the file.
     *
     * @return array<int, array<string, string|int|array<int>>>
     */
    public function tokenizeString($string, $eolChar, $stackPtr) {
        if (PHP_CODESNIFFER_VERBOSITY > 1) {
            echo "\t\t*** START COMMENT TOKENIZING ***" . PHP_EOL;
        }
        $tokens = [];
        $numChars = strlen($string);
        
        /*
            Doc block comments start with /*, but typically contain an
            extra star when they are used for function and class comments.
        */
        $char = $numChars - strlen(ltrim($string, '/*'));
        $lastChars = substr($string, -2);
        if ($char === $numChars && $lastChars === '*/') {
            // Edge case: docblock without whitespace or contents.
            $openTag = substr($string, 0, -2);
            $string = $lastChars;
        }
        else {
            $openTag = substr($string, 0, $char);
            $string = ltrim($string, '/*');
        }
        $tokens[$stackPtr] = [
            'content' => $openTag,
            'code' => T_DOC_COMMENT_OPEN_TAG,
            'type' => 'T_DOC_COMMENT_OPEN_TAG',
            'comment_tags' => [],
        ];
        $openPtr = $stackPtr;
        $stackPtr++;
        if (PHP_CODESNIFFER_VERBOSITY > 1) {
            $content = Common::prepareForOutput($openTag);
            echo "\t\tCreate comment token: T_DOC_COMMENT_OPEN_TAG => {$content}" . PHP_EOL;
        }
        
        /*
            Strip off the close tag so it doesn't interfere with any
            of our comment line processing. The token will be added to the
            stack just before we return it.
        */
        $closeTag = [
            'content' => substr($string, strlen(rtrim($string, '/*'))),
            'code' => T_DOC_COMMENT_CLOSE_TAG,
            'type' => 'T_DOC_COMMENT_CLOSE_TAG',
            'comment_opener' => $openPtr,
        ];
        if ($closeTag['content'] === false) {
            // In PHP < 8.0 substr() can return `false` instead of always returning a string.
            $closeTag['content'] = '';
        }
        $string = rtrim($string, '/*');
        
        /*
            Process each line of the comment.
        */
        $lines = explode($eolChar, $string);
        $numLines = count($lines);
        foreach ($lines as $lineNum => $string) {
            if ($lineNum !== $numLines - 1) {
                $string .= $eolChar;
            }
            $char = 0;
            $numChars = strlen($string);
            // We've started a new line, so process the indent.
            $space = $this->collectWhitespace($string, $char, $numChars);
            if ($space !== null) {
                $tokens[$stackPtr] = $space;
                $stackPtr++;
                if (PHP_CODESNIFFER_VERBOSITY > 1) {
                    $content = Common::prepareForOutput($space['content']);
                    echo "\t\tCreate comment token: T_DOC_COMMENT_WHITESPACE => {$content}" . PHP_EOL;
                }
                $char += strlen($space['content']);
                if ($char === $numChars) {
                    break;
                }
            }
            if ($string === '') {
                continue;
            }
            if ($lineNum > 0 && $string[$char] === '*') {
                // This is a function or class doc block line.
                $char++;
                $tokens[$stackPtr] = [
                    'content' => '*',
                    'code' => T_DOC_COMMENT_STAR,
                    'type' => 'T_DOC_COMMENT_STAR',
                ];
                $stackPtr++;
                if (PHP_CODESNIFFER_VERBOSITY > 1) {
                    echo "\t\tCreate comment token: T_DOC_COMMENT_STAR => *" . PHP_EOL;
                }
            }
            // Now we are ready to process the actual content of the line.
            $lineTokens = $this->processLine($string, $eolChar, $char, $numChars);
            foreach ($lineTokens as $lineToken) {
                $tokens[$stackPtr] = $lineToken;
                if (PHP_CODESNIFFER_VERBOSITY > 1) {
                    $content = Common::prepareForOutput($lineToken['content']);
                    $type = $lineToken['type'];
                    echo "\t\tCreate comment token: {$type} => {$content}" . PHP_EOL;
                }
                if ($lineToken['code'] === T_DOC_COMMENT_TAG) {
                    $tokens[$openPtr]['comment_tags'][] = $stackPtr;
                }
                $stackPtr++;
            }
        }
        
        //end foreach
        $tokens[$stackPtr] = $closeTag;
        $tokens[$openPtr]['comment_closer'] = $stackPtr;
        if (PHP_CODESNIFFER_VERBOSITY > 1) {
            $content = Common::prepareForOutput($closeTag['content']);
            echo "\t\tCreate comment token: T_DOC_COMMENT_CLOSE_TAG => {$content}" . PHP_EOL;
        }
        if (PHP_CODESNIFFER_VERBOSITY > 1) {
            echo "\t\t*** END COMMENT TOKENIZING ***" . PHP_EOL;
        }
        return $tokens;
    }
    
    //end tokenizeString()
    
    /**
     * Process a single line of a comment.
     *
     * @param string $string  The comment string being tokenized.
     * @param string $eolChar The EOL character to use for splitting strings.
     * @param int    $start   The position in the string to start processing.
     * @param int    $end     The position in the string to end processing.
     *
     * @return array<int, array<string, string|int>>
     */
    private function processLine($string, $eolChar, $start, $end) {
        $tokens = [];
        // Collect content padding.
        $space = $this->collectWhitespace($string, $start, $end);
        if ($space !== null) {
            $tokens[] = $space;
            $start += strlen($space['content']);
        }
        if (isset($string[$start]) === false) {
            return $tokens;
        }
        if ($string[$start] === '@') {
            // The content up until the first whitespace is the tag name.
            $matches = [];
            preg_match('/@[^\\s]+/', $string, $matches, 0, $start);
            if (isset($matches[0]) === true && substr(strtolower($matches[0]), 0, 7) !== '@phpcs:') {
                $tagName = $matches[0];
                $start += strlen($tagName);
                $tokens[] = [
                    'content' => $tagName,
                    'code' => T_DOC_COMMENT_TAG,
                    'type' => 'T_DOC_COMMENT_TAG',
                ];
                // Then there will be some whitespace.
                $space = $this->collectWhitespace($string, $start, $end);
                if ($space !== null) {
                    $tokens[] = $space;
                    $start += strlen($space['content']);
                }
            }
        }
        
        //end if
        // Process the rest of the line.
        $eol = strpos($string, $eolChar, $start);
        if ($eol === false) {
            $eol = $end;
        }
        if ($eol > $start) {
            $tokens[] = [
                'content' => substr($string, $start, $eol - $start),
                'code' => T_DOC_COMMENT_STRING,
                'type' => 'T_DOC_COMMENT_STRING',
            ];
        }
        if ($eol !== $end) {
            $tokens[] = [
                'content' => substr($string, $eol, strlen($eolChar)),
                'code' => T_DOC_COMMENT_WHITESPACE,
                'type' => 'T_DOC_COMMENT_WHITESPACE',
            ];
        }
        return $tokens;
    }
    
    //end processLine()
    
    /**
     * Collect consecutive whitespace into a single token.
     *
     * @param string $string The comment string being tokenized.
     * @param int    $start  The position in the string to start processing.
     * @param int    $end    The position in the string to end processing.
     *
     * @return array<string, string|int>|null
     */
    private function collectWhitespace($string, $start, $end) {
        $space = '';
        for ($start; $start < $end; $start++) {
            if ($string[$start] !== ' ' && $string[$start] !== "\t") {
                break;
            }
            $space .= $string[$start];
        }
        if ($space === '') {
            return null;
        }
        return [
            'content' => $space,
            'code' => T_DOC_COMMENT_WHITESPACE,
            'type' => 'T_DOC_COMMENT_WHITESPACE',
        ];
    }
    
    //end collectWhitespace()

}