notification_handler.php

<?php
// Handle AJAX requests for notifications
include 'config.php';

if (isset($_POST['action'])) {
    header('Content-Type: application/json');

    if ($_POST['action'] === 'get_notifications') {
        $user_id = $_SESSION['user_id'];
        $query = "SELECT id, title, message, created_at, is_read FROM notifications WHERE user_id = ? ORDER BY created_at DESC LIMIT 20";
        $stmt = $conn->prepare($query);
        $stmt->bind_param('i', $user_id);
        $stmt->execute();
        $result = $stmt->get_result();

        $notifications = [];
        while ($row = $result->fetch_assoc()) {
            $notifications[] = [
                'id' => (int)$row['id'],
                'title' => $row['title'],
                'message' => $row['message'],
                'created_at' => $row['created_at'],
                'is_read' => (bool)$row['is_read']
            ];
        }
        $stmt->close();

        echo json_encode(['success' => true, 'notifications' => $notifications]);
        exit();
    }

    if ($_POST['action'] === 'get_unread_count') {
        $user_id = $_SESSION['user_id'];
        $query = "SELECT COUNT(*) as count FROM notifications WHERE user_id = ? AND is_read = 0";
        $stmt = $conn->prepare($query);
        $stmt->bind_param('i', $user_id);
        $stmt->execute();
        $result = $stmt->get_result();
        $row = $result->fetch_assoc();
        $stmt->close();

        echo json_encode(['success' => true, 'count' => (int)$row['count']]);
        exit();
    }

    if ($_POST['action'] === 'mark_notification_read') {
        $notification_id = (int)$_POST['notification_id'];
        $user_id = $_SESSION['user_id'];

        $query = "UPDATE notifications SET is_read = 1 WHERE id = ? AND user_id = ?";
        $stmt = $conn->prepare($query);
        $stmt->bind_param('ii', $notification_id, $user_id);
        $success = $stmt->execute();
        $stmt->close();

        echo json_encode(['success' => $success]);
        exit();
    }

    if ($_POST['action'] === 'mark_all_notifications_read') {
        $user_id = $_SESSION['user_id'];

        $query = "UPDATE notifications SET is_read = 1 WHERE user_id = ? AND is_read = 0";
        $stmt = $conn->prepare($query);
        $stmt->bind_param('i', $user_id);
        $success = $stmt->execute();
        $stmt->close();

        echo json_encode(['success' => $success]);
        exit();
    }

    if ($_POST['action'] === 'clear_all_notifications') {
        $user_id = $_SESSION['user_id'];

        $query = "DELETE FROM notifications WHERE user_id = ?";
        $stmt = $conn->prepare($query);
        if (!$stmt) {
            echo json_encode(['success' => false, 'message' => 'Database prepare failed: ' . $conn->error]);
            exit();
        }
        $stmt->bind_param('i', $user_id);
        $success = $stmt->execute();
        if (!$success) {
            echo json_encode(['success' => false, 'message' => 'Database execute failed: ' . $stmt->error]);
            exit();
        }
        $affected_rows = $stmt->affected_rows;
        $stmt->close();

        echo json_encode(['success' => true, 'message' => 'Cleared ' . $affected_rows . ' notifications']);
        exit();
    }

    if ($_POST['action'] === 'delete_single_notification') {
        $notification_id = (int)$_POST['notification_id'];
        $user_id = $_SESSION['user_id'];

        $query = "DELETE FROM notifications WHERE id = ? AND user_id = ?";
        $stmt = $conn->prepare($query);
        if (!$stmt) {
            echo json_encode(['success' => false, 'message' => 'Database prepare failed: ' . $conn->error]);
            exit();
        }
        $stmt->bind_param('ii', $notification_id, $user_id);
        $success = $stmt->execute();
        if (!$success) {
            echo json_encode(['success' => false, 'message' => 'Database execute failed: ' . $stmt->error]);
            exit();
        }
        $affected_rows = $stmt->affected_rows;
        $stmt->close();

        echo json_encode(['success' => $affected_rows > 0, 'message' => $affected_rows > 0 ? 'Notification deleted' : 'Notification not found']);
        exit();
    }
}
?>