From d01d0b932b5b79ca8405e284bb0f619d33453ec0 Mon Sep 17 00:00:00 2001
From: Hamza-Ayed <hamzaayedflutter@gmail.com>
Date: Sat, 1 Aug 2026 22:40:27 +0300
Subject: [PATCH] Deploy: 2026-08-01 22:40:27

---
 .../app/Controllers/WhatsAppController.php    |  2 +
 backend/app/Models/WhatsAppSession.php        | 99 +++++++++++++++++--
 2 files changed, 93 insertions(+), 8 deletions(-)

diff --git a/backend/app/Controllers/WhatsAppController.php b/backend/app/Controllers/WhatsAppController.php
index 4b7bbaa..83c6465 100644
--- a/backend/app/Controllers/WhatsAppController.php
+++ b/backend/app/Controllers/WhatsAppController.php
@@ -152,6 +152,7 @@ class WhatsAppController extends BaseController
             'status' => 'disconnected'
         ]);
 
+        WhatsAppSession::clearSessionsCache($companyId);
         $newSession = WhatsAppSession::findSecure((int)$id);
 
         $response->json([
@@ -197,6 +198,7 @@ class WhatsAppController extends BaseController
         curl_close($ch);
 
         WhatsAppSession::delete((int)$sessionId);
+        WhatsAppSession::clearSessionsCache($companyId);
 
         $response->json(['status' => 'success', 'message' => 'Session deleted successfully']);
     }
diff --git a/backend/app/Models/WhatsAppSession.php b/backend/app/Models/WhatsAppSession.php
index 179e058..49e1b27 100644
--- a/backend/app/Models/WhatsAppSession.php
+++ b/backend/app/Models/WhatsAppSession.php
@@ -3,22 +3,96 @@
 namespace App\Models;
 
 use App\Core\Security;
-
 use App\Core\Database;
+use App\Core\Cache;
 
 /**
  * WhatsAppSession Model
- * Handles the whatsapp_sessions table with encryption for phone and QR code.
+ * Handles the whatsapp_sessions table with encryption for phone and QR code,
+ * Redis caching of connected sessions, and Round-Robin distribution for outbound messages.
  */
 class WhatsAppSession extends BaseModel
 {
     protected static string $table = 'whatsapp_sessions';
 
     /**
-     * Get the session for a specific company
+     * Clear cached connected sessions for a company
      */
-    public static function findByCompany(int $companyId)
+    public static function clearSessionsCache(int $companyId): void
     {
+        Cache::delete("connected_sessions:company_{$companyId}");
+    }
+
+    /**
+     * Get all active connected sessions for a company (cached via Redis if available)
+     */
+    public static function getConnectedSessionsForCompany(int $companyId): array
+    {
+        $cacheKey = "connected_sessions:company_{$companyId}";
+        $cached = Cache::get($cacheKey);
+        if ($cached !== null && is_array($cached)) {
+            return $cached;
+        }
+
+        $sessions = Database::select(
+            "SELECT * FROM " . static::$table . " WHERE company_id = ? AND status = 'connected' ORDER BY id ASC",
+            [$companyId]
+        );
+
+        foreach ($sessions as &$session) {
+            $session['phone'] = $session['phone'] ? Security::decrypt($session['phone']) : null;
+            $session['qr_code'] = $session['qr_code'] ? Security::decrypt($session['qr_code']) : null;
+        }
+
+        Cache::set($cacheKey, $sessions, 3000); // Cache for 50 minutes
+        return $sessions;
+    }
+
+    /**
+     * Get next connected session using Round-Robin strategy via Redis
+     */
+    public static function getRoundRobinSession(int $companyId): ?array
+    {
+        $connectedSessions = static::getConnectedSessionsForCompany($companyId);
+
+        if (empty($connectedSessions)) {
+            // Fallback to legacy single session if no connected sessions are found
+            return static::findByCompany($companyId, false);
+        }
+
+        $count = count($connectedSessions);
+        if ($count === 1) {
+            return $connectedSessions[0];
+        }
+
+        $rrKey = "rr_index:company_{$companyId}";
+        $currentIndex = Cache::get($rrKey);
+        if ($currentIndex === null || !is_numeric($currentIndex)) {
+            $currentIndex = 0;
+        } else {
+            $currentIndex = (int)$currentIndex;
+        }
+
+        $selectedIndex = $currentIndex % $count;
+        $nextIndex = ($selectedIndex + 1) % $count;
+
+        Cache::set($rrKey, $nextIndex, 86400);
+
+        return $connectedSessions[$selectedIndex];
+    }
+
+    /**
+     * Get the session for a specific company (defaults to Round-Robin among connected sessions)
+     */
+    public static function findByCompany(int $companyId, bool $useRoundRobin = true)
+    {
+        if ($useRoundRobin) {
+            $session = static::getRoundRobinSession($companyId);
+            if ($session) {
+                return $session;
+            }
+        }
+
         $session = Database::selectOne(
             "SELECT * FROM " . static::$table . " WHERE company_id = ? LIMIT 1",
             [$companyId]
@@ -110,7 +184,7 @@ class WhatsAppSession extends BaseModel
      */
     public static function findOrCreate(int $companyId, string $name = 'Main WhatsApp')
     {
-        $session = static::findByCompany($companyId);
+        $session = static::findByCompany($companyId, false);
         if ($session) {
             return $session;
         }
@@ -124,11 +198,12 @@ class WhatsAppSession extends BaseModel
             'status' => 'disconnected'
         ]);
 
-        return static::findByCompany($companyId);
+        static::clearSessionsCache($companyId);
+        return static::findByCompany($companyId, false);
     }
 
     /**
-     * Update session state securely
+     * Update session state securely and clear Redis cache
      */
     public static function updateState(int $id, array $data)
     {
@@ -141,6 +216,14 @@ class WhatsAppSession extends BaseModel
             $data['qr_code'] = Security::encrypt($data['qr_code']);
         }
 
-        return static::update($id, $data);
+        $session = Database::selectOne("SELECT company_id FROM " . static::$table . " WHERE id = ? LIMIT 1", [$id]);
+        $result = static::update($id, $data);
+
+        if ($session && !empty($session['company_id'])) {
+            static::clearSessionsCache((int)$session['company_id']);
+        }
+
+        return $result;
     }
 }
+