<?php

/**
 * 文件功能：Kafka 消费者服务
 *
 * @author   ChatRoom Laravel
 *
 * @version  1.0.0
 */

namespace App\Services\WechatBot;

use App\Models\SysParam;
use Illuminate\Support\Facades\Log;
use longlang\phpkafka\Consumer\Consumer;
use longlang\phpkafka\Consumer\ConsumerConfig;

class KafkaConsumerService
{
    /**
     * Kafka Broker 地址
     */
    protected string $brokers = '';

    /**
     * 消费 Topic
     */
    protected string $topic = '';

    /**
     * 消费者组 ID
     */
    protected string $groupId = '';

    /**
     * 构造函数 — 从 SysParam 获取配置
     */
    public function __construct()
    {
        $param = SysParam::where('alias', 'wechat_bot_config')->first();
        if ($param && ! empty($param->body)) {
            $config = json_decode($param->body, true);
            $this->brokers = $config['kafka']['brokers'] ?? '';
            $this->topic = $config['kafka']['topic'] ?? '';
            $this->groupId = $config['kafka']['group_id'] ?? 'chatroom_wechat_bot';
        }
    }

    /**
     * 创建 Kafka 消费者实例
     */
    public function createConsumer(): ?Consumer
    {
        if (empty($this->brokers) || empty($this->topic)) {
            Log::warning('WechatBot Kafka: brokers or topic is empty. Consumer not started.');

            return null;
        }

        $config = new ConsumerConfig;
        $config->setBroker($this->brokers);
        $config->setTopic($this->topic);
        $config->setGroupId($this->groupId);
        $config->setClientId('chatroom_wechat_bot_'.getmypid().'_'.uniqid());
        $config->setGroupInstanceId('chatroom_wechat_bot_instance_'.getmypid().'_'.uniqid());
        $config->setInterval(0.5);           // 拉取间隔（秒）
        $config->setGroupRetry(5);           // 组协调重试次数
        $config->setGroupRetrySleep(1);      // 组协调重试间隔（秒）

        return new Consumer($config);
    }

    /**
     * 解析 Kafka 原始消息，提取有效的聊天消息列表
     *
     * @param  string  $rawJson  Kafka 消息体 JSON 字符串
     * @return array 解析后的消息数组
     */
    public function parseKafkaMessage(string $rawJson): array
    {
        try {
            $data = json_decode($rawJson, true, 512, JSON_THROW_ON_ERROR);
        } catch (\JsonException $e) {
            Log::warning('微信机器人 Kafka 消息 JSON 解析失败', ['error' => $e->getMessage()]);

            return [];
        }

        // 只处理包含 AddMsgs 的消息
        $addMsgs = $data['AddMsgs'] ?? [];
        if (empty($addMsgs)) {
            return [];
        }

        $messages = [];
        foreach ($addMsgs as $msg) {
            $fromUser = $msg['from_user_name']['str'] ?? '';
            $toUser = $msg['to_user_name']['str'] ?? '';
            $msgType = $msg['msg_type'] ?? 0;
            $content = $msg['content']['str'] ?? '';

            // 判断是否来自群聊
            $isChatroom = str_contains($fromUser, '@chatroom');

            // 群聊消息中，from_user 是群ID，实际发送者在 content 中以 "wxid:\n内容" 格式出现
            $actualSender = $fromUser;
            $actualContent = $content;
            $chatroomId = null;

            if ($isChatroom) {
                $chatroomId = $fromUser;
                // 解析群聊消息格式: "发送者wxid:\n实际内容"
                if (preg_match('/^(.+?):\n(.*)$/s', $content, $matches)) {
                    $actualSender = $matches[1];
                    $actualContent = $matches[2];
                }
            }

            $messages[] = [
                'msg_id' => $msg['new_msg_id'] ?? $msg['msg_id'] ?? 0,
                'from_user' => $actualSender,
                'to_user' => $toUser,
                'chatroom_id' => $chatroomId,
                'msg_type' => $msgType,
                'content' => $actualContent,
                'raw_content' => $content,
                'is_chatroom' => $isChatroom,
            ];
        }

        return $messages;
    }
}