<?php
/**
 * VR票务插件 - 基础服务
 *
 * @package vr_ticket\service
 */

namespace app\plugins\vr_ticket\service;

class BaseService
{
    /**
     * 获取插件表前缀
     */
    public static function table($name)
    {
        return 'plugins_vr_' . $name;
    }

    /**
     * 获取当前时间戳
     */
    public static function now()
    {
        return time();
    }

    /**
     * 生成 UUID v4 票码
     */
    public static function generateUuid()
    {
        $data = random_bytes(16);
        $data[6] = chr(ord($data[6]) & 0x0f | 0x40);
        $data[8] = chr(ord($data[8]) & 0x3f | 0x80);
        return vsprintf('%s%s-%s-%s-%s-%s%s%s', str_split(bin2hex($data), 4));
    }

    /**
     * AES-256-CBC 加密 QR 数据
     *
     * @param array $data 待加密数据
     * @param int|null $expire 过期时间戳（默认30天）
     * @return string base64 编码密文
     */
    public static function encryptQrData($data, $expire = null)
    {
        $secret = self::getQrSecret();
        $expire = $expire ?? (time() + 86400 * 30);

        $payload = json_encode(array_merge($data, [
            'exp' => $expire,
            'iat' => time(),
        ]), JSON_UNESCAPED_UNICODE);

        $iv = random_bytes(16);
        $encrypted = openssl_encrypt($payload, 'AES-256-CBC', $secret, OPENSSL_RAW_DATA, $iv);

        return base64_encode($iv . $encrypted);
    }

    /**
     * 解密 QR 数据
     *
     * @param string $encoded base64 编码密文
     * @return array|null
     */
    public static function decryptQrData($encoded)
    {
        $secret = self::getQrSecret();
        $combined = base64_decode($encoded);

        if (strlen($combined) < 16) {
            return null;
        }

        $iv = substr($combined, 0, 16);
        $encrypted = substr($combined, 16);

        $decrypted = openssl_decrypt($encrypted, 'AES-256-CBC', $secret, OPENSSL_RAW_DATA, $iv);

        if ($decrypted === false) {
            return null;
        }

        $data = json_decode($decrypted, true);

        if (isset($data['exp']) && $data['exp'] < time()) {
            return null;
        }

        return $data;
    }

    /**
     * 获取 QR 加密密钥
     */
    private static function getQrSecret()
    {
        // 优先从环境变量读取
        $secret = env('VR_TICKET_QR_SECRET', '');
        if (!empty($secret)) {
            return $secret;
        }
        // 回退：使用 ShopXO 应用密钥
        return config('shopxo.app_key', 'shopxo_default_secret_change_me');
    }

    /**
     * 判断商品是否为票务商品
     *
     * @param int $goods_id
     * @return bool
     */
    public static function isTicketGoods($goods_id)
    {
        $goods = \Db::name('Goods')->find($goods_id);
        if (empty($goods)) {
            return false;
        }
        return !empty($goods['venue_data']) || ($goods['item_type'] ?? '') === 'ticket';
    }

    /**
     * 获取商品座位模板
     *
     * @param int $goods_id
     * @return array|null
     */
    public static function getSeatTemplateByGoods($goods_id)
    {
        $goods = \Db::name('Goods')->find($goods_id);
        if (empty($goods) || empty($goods['category_id'])) {
            return null;
        }

        return \Db::name(self::table('seat_templates'))
            ->where('category_id', $goods['category_id'])
            ->where('status', 1)
            ->find();
    }

    /**
     * 安全日志
     */
    public static function log($message, $context = [], $level = 'info')
    {
        $tag = '[vr_ticket]';
        $ctx = empty($context) ? '' : ' ' . json_encode($context, JSON_UNESCAPED_UNICODE);
        $log_func = "log_{$level}";
        if (function_exists($log_func)) {
            $log_func($tag . $message . $ctx);
        }
    }
}