<?php
// PushHelper.php
require_once __DIR__ . '/vendor/autoload.php';

use Minishlink\WebPush\WebPush;
use Minishlink\WebPush\Subscription;

class PushHelper {
    public static function sendPush($pdo, $id_account, $title, $body, $url = '/dashboard.php') {
        try {
            // Validate: only send push if account exists
            $checkStmt = $pdo->prepare("SELECT id_account FROM account WHERE id_account = ?");
            $checkStmt->execute([$id_account]);
            $accountData = $checkStmt->fetch(PDO::FETCH_ASSOC);

            if (!$accountData) {
                return; // Account deleted
            }


            $keys = require __DIR__ . '/push_config.php';
            
            $auth = [
                'VAPID' => [
                    'subject' => $keys['VAPID_SUBJECT'],
                    'publicKey' => $keys['VAPID_PUBLIC_KEY'],
                    'privateKey' => $keys['VAPID_PRIVATE_KEY'],
                ],
            ];

            // Instantiate WebPush
            $webPush = new WebPush($auth);

            $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");

            // Fetch subscriptions for this specific account
            $stmt = $pdo->prepare("SELECT endpoint, p256dh, auth FROM push_subscriptions WHERE id_account = ?");
            $stmt->execute([$id_account]);
            $subs = $stmt->fetchAll(PDO::FETCH_ASSOC);

            $payload = json_encode([
                'title' => $title,
                'body' => $body,
                'url' => $url,
                'icon' => '/images/myn.png'
            ]);

            foreach ($subs as $subData) {
                $subscription = Subscription::create([
                    'endpoint' => $subData['endpoint'],
                    'publicKey' => $subData['p256dh'], // corresponds to p256dh
                    'authToken' => $subData['auth'],   // corresponds to auth
                ]);

                // Queue the notification with High Urgency for immediate delivery
                $webPush->queueNotification($subscription, $payload, ['urgency' => 'high']);
            }

            // Send all queued notifications
            foreach ($webPush->flush() as $report) {
                $endpoint = $report->getRequest()->getUri()->__toString();
                if (!$report->isSuccess()) {
                    // If endpoint is expired/invalid, remove it from DB to clean up
                    if ($report->isSubscriptionExpired()) {
                        $del = $pdo->prepare("DELETE FROM push_subscriptions WHERE endpoint = ?");
                        $del->execute([$endpoint]);
                    }
                    $errReason = "Push Failed for {$endpoint}: " . $report->getReason();
                    file_put_contents(__DIR__ . '/push_error.log', "[" . date('Y-m-d H:i:s') . "] " . $errReason . "\n", FILE_APPEND);
                    error_log($errReason);
                }
            }
        } catch (\Exception $e) {
            $err = "[" . date('Y-m-d H:i:s') . "] PushHelper Fatal Error: " . $e->getMessage() . "\n";
            file_put_contents(__DIR__ . '/push_error.log', $err, FILE_APPEND);
            error_log($err);
        }
    }

    public static function broadcastToAdmins($pdo, $title, $body, $url = '/dashboard.php') {
        // Broadcast to all subscribed accounts (admins)
        try {
            $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");

            $stmt = $pdo->query("SELECT DISTINCT id_account FROM push_subscriptions WHERE id_account > 0");
            $admins = $stmt->fetchAll(PDO::FETCH_ASSOC);
            foreach ($admins as $admin) {
                self::sendPush($pdo, $admin['id_account'], $title, $body, $url);
            }
        } catch (\PDOException $e) {
            $err = "[" . date('Y-m-d H:i:s') . "] PushHelper DB Error: " . $e->getMessage() . "\n";
            file_put_contents(__DIR__ . '/push_error.log', $err, FILE_APPEND);
            error_log($err);
        }
    }
}