refactor: general code base refactor (#2950)

* refactor

* fix: bug in previous refactor

* chore: exclude phpcompat sniff due to bug in phpcompat

* fix: do not leak absolute paths

* refactor/fix: batch extensions checking, fix DOS issue

lib/utils.php

@@ -0,0 +1,123 @@
+<?php
+
+final class HttpException extends \Exception
+{
+}
+
+final class Json
+{
+    public static function encode($value): string
+    {
+        $flags = JSON_PRETTY_PRINT | JSON_THROW_ON_ERROR | JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE;
+        return \json_encode($value, $flags);
+    }
+
+    public static function decode(string $json, bool $assoc = true)
+    {
+        return \json_decode($json, $assoc, 512, JSON_THROW_ON_ERROR);
+    }
+}
+
+function create_sane_stacktrace(\Throwable $e): array
+{
+    $frames = array_reverse($e->getTrace());
+    $frames[] = [
+        'file' => $e->getFile(),
+        'line' => $e->getLine(),
+    ];
+    $stackTrace = [];
+    foreach ($frames as $i => $frame) {
+        $file = $frame['file'] ?? '(no file)';
+        $line = $frame['line'] ?? '(no line)';
+        $stackTrace[] = sprintf(
+            '#%s %s:%s',
+            $i,
+            trim_path_prefix($file),
+            $line,
+        );
+    }
+    return $stackTrace;
+}
+
+/**
+ * Trim path prefix for privacy/security reasons
+ *
+ * Example: "/var/www/rss-bridge/index.php" => "index.php"
+ */
+function trim_path_prefix(string $filePath): string
+{
+    return mb_substr($filePath, mb_strlen(dirname(__DIR__)) + 1);
+}
+
+/**
+ * This is buggy because strip tags removes a lot that isn't html
+ */
+function is_html(string $text): bool
+{
+    return strlen(strip_tags($text)) !== strlen($text);
+}
+
+/**
+ * Determines the MIME type from a URL/Path file extension.
+ *
+ * _Remarks_:
+ *
+ * * The built-in functions `mime_content_type` and `fileinfo` require fetching
+ * remote contents.
+ * * A caller can hint for a MIME type by appending `#.ext` to the URL (i.e. `#.image`).
+ *
+ * Based on https://stackoverflow.com/a/1147952
+ *
+ * @param string $url The URL or path to the file.
+ * @return string The MIME type of the file.
+ */
+function parse_mime_type($url)
+{
+    static $mime = null;
+
+    if (is_null($mime)) {
+        // Default values, overriden by /etc/mime.types when present
+        $mime = [
+            'jpg' => 'image/jpeg',
+            'gif' => 'image/gif',
+            'png' => 'image/png',
+            'image' => 'image/*',
+            'mp3' => 'audio/mpeg',
+        ];
+        // '@' is used to mute open_basedir warning, see issue #818
+        if (@is_readable('/etc/mime.types')) {
+            $file = fopen('/etc/mime.types', 'r');
+            while (($line = fgets($file)) !== false) {
+                $line = trim(preg_replace('/#.*/', '', $line));
+                if (!$line) {
+                    continue;
+                }
+                $parts = preg_split('/\s+/', $line);
+                if (count($parts) == 1) {
+                    continue;
+                }
+                $type = array_shift($parts);
+                foreach ($parts as $part) {
+                    $mime[$part] = $type;
+                }
+            }
+            fclose($file);
+        }
+    }
+
+    if (strpos($url, '?') !== false) {
+        $url_temp = substr($url, 0, strpos($url, '?'));
+        if (strpos($url, '#') !== false) {
+            $anchor = substr($url, strpos($url, '#'));
+            $url_temp .= $anchor;
+        }
+        $url = $url_temp;
+    }
+
+    $ext = strtolower(pathinfo($url, PATHINFO_EXTENSION));
+    if (!empty($mime[$ext])) {
+        return $mime[$ext];
+    }
+
+    return 'application/octet-stream';
+}