Delete dead helpers/OutputHelper.php (#54)

Zero callers anywhere in the app — confirmed via grep for
"OutputHelper::" across the whole codebase. Every view actually calls
htmlspecialchars() directly instead, which a prior audit confirmed is
done consistently, so escaping was never actually at risk. This was
just a misleading, unused class that README.md's file reference
implied was part of the app's active XSS-prevention story. Removed the
file and its README Project Structure entry.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01MGDKHiU5RJdo3dqQUDow3X

README.md

@@ -362,7 +362,6 @@ tinker_tickets/
 │   ├── Database.php                      # Centralized mysqli connection
 │   ├── ErrorHandler.php                  # Global error/exception handler
 │   ├── NotificationHelper.php            # Matrix hookshot webhook events
-│   ├── OutputHelper.php                  # Safe HTML output helpers
 │   ├── ResponseHelper.php                # JSON API response helpers
 │   ├── SynapseHelper.php                 # Resolves usernames → Matrix IDs via Synapse admin API
 │   └── UrlHelper.php                     # Canonical ticket URLs using APP_DOMAIN

helpers/OutputHelper.php

@@ -1,212 +0,0 @@
-<?php
-
-/**
- * OutputHelper - Consistent output escaping utilities
- *
- * Provides secure HTML escaping functions to prevent XSS attacks.
- * Use these functions when outputting user-controlled data.
- */
-class OutputHelper
-{
-    /**
-     * Escape string for HTML output
-     *
-     * Use for text content inside HTML elements.
-     * Example: <p><?= OutputHelper::h($userInput) ?></p>
-     *
-     * @param string|null $string The string to escape
-     * @param int $flags htmlspecialchars flags (default: ENT_QUOTES | ENT_HTML5)
-     * @return string Escaped string
-     */
-    public static function h(?string $string, int $flags = ENT_QUOTES | ENT_HTML5): string
-    {
-        if ($string === null) {
-            return '';
-        }
-        return htmlspecialchars($string, $flags, 'UTF-8');
-    }
-
-    /**
-     * Escape string for HTML attribute context
-     *
-     * Use for values inside HTML attributes.
-     * Example: <input value="<?= OutputHelper::attr($userInput) ?>">
-     *
-     * @param string|null $string The string to escape
-     * @return string Escaped string
-     */
-    public static function attr(?string $string): string
-    {
-        if ($string === null) {
-            return '';
-        }
-        // More aggressive escaping for attribute context
-        return htmlspecialchars($string, ENT_QUOTES | ENT_HTML5 | ENT_SUBSTITUTE, 'UTF-8');
-    }
-
-    /**
-     * Encode data as JSON for JavaScript context
-     *
-     * Use when embedding data in JavaScript.
-     * Example: <script>const data = <?= OutputHelper::json($data) ?>;</script>
-     *
-     * @param mixed $data The data to encode
-     * @param int $flags json_encode flags
-     * @return string JSON encoded string (safe for script context)
-     */
-    public static function json($data, int $flags = 0): string
-    {
-        // Use HEX encoding for safety in HTML context
-        $safeFlags = JSON_HEX_TAG | JSON_HEX_APOS | JSON_HEX_QUOT | JSON_HEX_AMP | $flags;
-        return json_encode($data, $safeFlags);
-    }
-
-    /**
-     * URL encode a string
-     *
-     * Use for values in URL query strings.
-     * Example: <a href="/search?q=<?= OutputHelper::url($query) ?>">
-     *
-     * @param string|null $string The string to encode
-     * @return string URL encoded string
-     */
-    public static function url(?string $string): string
-    {
-        if ($string === null) {
-            return '';
-        }
-        return rawurlencode($string);
-    }
-
-    /**
-     * Escape for CSS context
-     *
-     * Use for values in inline CSS.
-     * Example: <div style="color: <?= OutputHelper::css($color) ?>;">
-     *
-     * @param string|null $string The string to escape
-     * @return string Escaped string (only allows safe characters)
-     */
-    public static function css(?string $string): string
-    {
-        if ($string === null) {
-            return '';
-        }
-        // Only allow alphanumeric, hyphens, underscores, spaces, and common CSS values
-        if (!preg_match('/^[a-zA-Z0-9_\-\s#.,()%]+$/', $string)) {
-            return '';
-        }
-        return $string;
-    }
-
-    /**
-     * Format a number safely
-     *
-     * Ensures output is always a valid number.
-     *
-     * @param mixed $number The number to format
-     * @param int $decimals Number of decimal places
-     * @return string Formatted number
-     */
-    public static function number($number, int $decimals = 0): string
-    {
-        return number_format((float)$number, $decimals, '.', ',');
-    }
-
-    /**
-     * Format an integer safely
-     *
-     * @param mixed $value The value to format
-     * @return int Integer value
-     */
-    public static function int($value): int
-    {
-        return (int)$value;
-    }
-
-    /**
-     * Truncate string with ellipsis
-     *
-     * @param string|null $string The string to truncate
-     * @param int $length Maximum length
-     * @param string $suffix Suffix to add if truncated
-     * @return string Truncated and escaped string
-     */
-    public static function truncate(?string $string, int $length = 100, string $suffix = '...'): string
-    {
-        if ($string === null) {
-            return '';
-        }
-
-        if (mb_strlen($string, 'UTF-8') <= $length) {
-            return self::h($string);
-        }
-
-        return self::h(mb_substr($string, 0, $length, 'UTF-8')) . self::h($suffix);
-    }
-
-    /**
-     * Format a date safely
-     *
-     * @param string|int|null $date Date string, timestamp, or null
-     * @param string $format PHP date format
-     * @return string Formatted date
-     */
-    public static function date($date, string $format = 'Y-m-d H:i:s'): string
-    {
-        if ($date === null || $date === '') {
-            return '';
-        }
-
-        if (is_numeric($date)) {
-            return date($format, (int)$date);
-        }
-
-        $timestamp = strtotime($date);
-        if ($timestamp === false) {
-            return '';
-        }
-
-        return date($format, $timestamp);
-    }
-
-    /**
-     * Check if a string is safe for use as a CSS class name
-     *
-     * @param string $class The class name to validate
-     * @return bool True if safe
-     */
-    public static function isValidCssClass(string $class): bool
-    {
-        return preg_match('/^[a-zA-Z_][a-zA-Z0-9_-]*$/', $class) === 1;
-    }
-
-    /**
-     * Sanitize CSS class name(s)
-     *
-     * @param string|null $classes Space-separated class names
-     * @return string Sanitized class names
-     */
-    public static function cssClass(?string $classes): string
-    {
-        if ($classes === null || $classes === '') {
-            return '';
-        }
-
-        $classList = explode(' ', $classes);
-        $validClasses = array_filter($classList, [self::class, 'isValidCssClass']);
-
-        return implode(' ', $validClasses);
-    }
-}
-
-/**
- * Shorthand function for HTML escaping
- *
- * @param string|null $string The string to escape
- * @return string Escaped string
- */
-function h(?string $string): string
-{
-    return OutputHelper::h($string);
-}