<?php
// save_subscription.php
session_start();
require 'koneksi.php';

header('Content-Type: application/json');

if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    echo json_encode(['status' => 'error', 'message' => 'Invalid request method.']);
    exit;
}

$data = json_decode(file_get_contents('php://input'), true);

if (!isset($data['subscription'])) {
    echo json_encode(['status' => 'error', 'message' => 'Valid subscription object not found.']);
    exit;
}

// Ensure user is logged in
$id_account = isset($_SESSION['id_account']) ? (int)$_SESSION['id_account'] : 0;
if ($id_account === 0) {
    if (isset($_SESSION['user_id'])) {
        $id_account = (int)$_SESSION['user_id'];
    } else {
        echo json_encode(['status' => 'error', 'message' => 'User not logged in.']);
        exit;
    }
}

$sub = $data['subscription'];
$endpoint = $sub['endpoint'] ?? '';
$p256dh = $sub['keys']['p256dh'] ?? '';
$auth = $sub['keys']['auth'] ?? '';

if (empty($endpoint) || empty($p256dh) || empty($auth)) {
    echo json_encode(['status' => 'error', 'message' => 'Incomplete subscription keys.']);
    exit;
}

try {
    // Auto-create table if it doesn't exist on the hosting server
    $pdo->exec("CREATE TABLE IF NOT EXISTS push_subscriptions (
        id INT AUTO_INCREMENT PRIMARY KEY,
        id_account INT NOT NULL,
        endpoint TEXT NOT NULL,
        p256dh VARCHAR(255) NOT NULL,
        auth VARCHAR(255) NOT NULL,
        created_at TIMESTAMP DEFAULT CURRENT_TIMESTAMP
    ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4");

    // Check if THIS exact browser subscription already exists
    $stmt = $pdo->prepare("SELECT id FROM push_subscriptions WHERE endpoint = ?");
    $stmt->execute([$endpoint]);
    $existing = $stmt->fetch(PDO::FETCH_ASSOC);

    if ($existing) {
        // Update to make sure id_account is current (in case multiple accounts login on same browser)
        $upd = $pdo->prepare("UPDATE push_subscriptions SET id_account = ? WHERE id = ?");
        $upd->execute([$id_account, $existing['id']]);
        echo json_encode(['status' => 'success', 'message' => 'Subscription updated.']);
    } else {
        // Insert new subscription
        $ins = $pdo->prepare("INSERT INTO push_subscriptions (id_account, endpoint, p256dh, auth) VALUES (?, ?, ?, ?)");
        $ins->execute([$id_account, $endpoint, $p256dh, $auth]);
        echo json_encode(['status' => 'success', 'message' => 'Subscription saved.']);
    }
} catch (PDOException $e) {
    $err = "[" . date('Y-m-d H:i:s') . "] Save Subscription DB Error: " . $e->getMessage() . "\n";
    file_put_contents(__DIR__ . '/push_error.log', $err, FILE_APPEND);
    echo json_encode(['status' => 'error', 'message' => 'Database error: ' . $e->getMessage()]);
}