feat: per-server notification thresholds with alert on agent metrics push

src/Controllers/ApiController.php

@@ -15,6 +15,7 @@ use ServerManager\Services\AuditService;
 use ServerManager\Services\PermissionValidator;
 use ServerManager\Services\FCMService;
 use ServerManager\Models\CommandHistory;
+use ServerManager\Models\Notification;
 use ServerManager\Core\Validator;
 
 class ApiController
@@ -434,6 +435,38 @@ class ApiController
 
         $serverModel->updateAgentLastSeen((int) $server['id']);
 
+        $checks = [
+            'cpu'  => ['val' => $cpu,  'warn' => $server['threshold_cpu_warning'],  'crit' => $server['threshold_cpu_critical']],
+            'ram'  => ['val' => $ram,  'warn' => $server['threshold_ram_warning'],  'crit' => $server['threshold_ram_critical']],
+            'disk' => ['val' => $disk, 'warn' => $server['threshold_disk_warning'], 'crit' => $server['threshold_disk_critical']],
+        ];
+
+        $breaches = [];
+        foreach ($checks as $metric => $c) {
+            if ($c['crit'] !== null && $c['val'] >= (float) $c['crit']) {
+                $breaches[] = ['metric' => $metric, 'level' => 'critical', 'current' => $c['val'], 'threshold' => $c['crit']];
+            } elseif ($c['warn'] !== null && $c['val'] >= (float) $c['warn']) {
+                $breaches[] = ['metric' => $metric, 'level' => 'warning', 'current' => $c['val'], 'threshold' => $c['warn']];
+            }
+        }
+
+        if (!empty($breaches)) {
+            $userIds = $serverModel->getAccessibleUserIds((int) $server['id']);
+            $notificationModel = new Notification();
+            foreach ($breaches as $b) {
+                $title = strtoupper($b['metric']) . " {$b['level']} on {$server['name']}";
+                $message = "{$server['name']}: {$b['metric']} at {$b['current']}% ({$b['level']} threshold: {$b['threshold']}%)";
+                foreach ($userIds as $uid) {
+                    $notificationModel->create([
+                        'user_id' => (int) $uid,
+                        'title' => $title,
+                        'message' => $message,
+                        'type' => $b['level'],
+                    ]);
+                }
+            }
+        }
+
         $this->view->json(['success' => true]);
     }
 

src/Controllers/ServerController.php

@@ -1969,4 +1969,24 @@ class ServerController
         ]);
     }
 
+    public function saveThresholds(int $id): void
+    {
+        $server = $this->requireServerAccess($id, 'manager');
+        $role = $this->serverModel->getUserRole($id, (int) Session::get('user_id'));
+
+        if ($role !== 'owner') {
+            $this->view->json(['success' => false, 'error' => 'Only the server owner can modify notification thresholds.'], 403);
+        }
+
+        $fields = ['cpu_warning', 'cpu_critical', 'ram_warning', 'ram_critical', 'disk_warning', 'disk_critical'];
+        $data = [];
+        foreach ($fields as $f) {
+            $key = 'threshold_' . $f;
+            $data[$key] = isset($_POST[$f]) ? max(0, min(100, (float) $_POST[$f])) : null;
+        }
+
+        $this->serverModel->update($id, $data);
+        $this->auditService->log('thresholds_updated', 'server', $id, $data);
+        $this->view->json(['success' => true, 'message' => 'Notification thresholds updated.']);
+    }
 }

src/Core/Database.php

@@ -88,6 +88,11 @@ class Database
         return $this->query($sql, $params)->fetchAll();
     }
 
+    public function fetchCol(string $sql, array $params = []): array
+    {
+        return $this->query($sql, $params)->fetchAll(\PDO::FETCH_COLUMN);
+    }
+
     public function insert(string $table, array $data): int
     {
         $columns = implode(', ', array_keys($data));

src/Models/Server.php

@@ -410,6 +410,28 @@ class Server
         );
     }
 
+    public function getAccessibleUserIds(int $serverId): array
+    {
+        $direct = $this->db->fetchCol(
+            'SELECT user_id FROM server_user WHERE server_id = ? AND status = \'active\'',
+            [$serverId]
+        );
+
+        $team = $this->db->fetchCol(
+            'SELECT DISTINCT tu.user_id FROM team_user tu
+             JOIN team_server ts ON tu.team_id = ts.team_id
+             WHERE ts.server_id = ? AND tu.status = \'active\' AND ts.status = \'active\'',
+            [$serverId]
+        );
+
+        $owner = $this->db->fetchCol(
+            'SELECT created_by FROM servers WHERE id = ? AND status = \'active\'',
+            [$serverId]
+        );
+
+        return array_unique(array_merge($direct, $team, $owner));
+    }
+
     public function findByAgentKey(string $key): ?array
     {
         $server = $this->db->fetch(