postgres database implementation

config.php

@@ -34,13 +34,42 @@ function load_env() {
 // Automatically load on include
 load_env();
 
-function get_firebase_config(): array {
-    return [
-        'apiKey'            => getenv('FIREBASE_API_KEY') ?: '',
-        'authDomain'        => getenv('FIREBASE_AUTH_DOMAIN') ?: '',
-        'projectId'         => getenv('FIREBASE_PROJECT_ID') ?: '',
-        'storageBucket'     => getenv('FIREBASE_STORAGE_BUCKET') ?: '',
-        'messagingSenderId' => getenv('FIREBASE_MESSAGING_SENDER_ID') ?: '',
-        'appId'             => getenv('FIREBASE_APP_ID') ?: '',
-    ];
+/**
+ * Get a PDO connection to the database.
+ */
+function get_db_connection(): ?PDO {
+    static $pdo = null;
+    
+    if ($pdo !== null) {
+        return $pdo;
+    }
+    
+    $url = getenv('DATABASE_URL');
+    if (!$url) {
+        return null;
+    }
+    
+    $parsedUrl = parse_url($url);
+    if ($parsedUrl === false || !isset($parsedUrl['host'], $parsedUrl['user'], $parsedUrl['pass'], $parsedUrl['path'])) {
+        return null;
+    }
+    
+    $host = $parsedUrl['host'];
+    $port = $parsedUrl['port'] ?? 5432;
+    $user = $parsedUrl['user'];
+    $pass = $parsedUrl['pass'];
+    $db = ltrim($parsedUrl['path'], '/');
+    
+    $dsn = "pgsql:host=$host;port=$port;dbname=$db";
+    
+    try {
+        $pdo = new PDO($dsn, $user, $pass, [
+            PDO::ATTR_ERRMODE => PDO::ERRMODE_EXCEPTION,
+            PDO::ATTR_DEFAULT_FETCH_MODE => PDO::FETCH_ASSOC,
+        ]);
+        return $pdo;
+    } catch (PDOException $e) {
+        error_log("Database connection failed: " . $e->getMessage());
+        return null;
+    }
 }