//! 指令响应处理协程
//!
//! 从 Redis LIST `device:reply:{imei}` 读取设备指令响应，
//! 匹配 msg_id 并通过 oneshot channel 通知等待中的 HTTP 请求。

use redis::aio::ConnectionManager;

use crate::commands::PendingCommands;

/// 启动指令响应处理协程
///
/// 使用 BRPOP 阻塞等待所有 `device:reply:*` 队列的响应消息。
pub async fn start(redis: ConnectionManager, pending: PendingCommands) {
    tracing::info!("[reply_worker] 启动");

    loop {
        let mut conn = redis.clone();
        let result: Result<(String, String), redis::RedisError> = redis::cmd("BRPOP")
            .arg("device:replies")
            .arg(0)
            .query_async(&mut conn)
            .await;

        match result {
            Ok((_key, reply_json)) => {
                // 解析 msg_id
                if let Ok(reply) = serde_json::from_str::<serde_json::Value>(&reply_json) {
                    let msg_id = reply["msg_id"].as_u64().unwrap_or(0) as u32;
                    let pending = pending.clone();

                    tokio::spawn(async move {
                        if let Some(tx) = pending.remove(msg_id).await {
                            let _ = tx.send(reply);
                            tracing::debug!("[reply_worker] msg_id={} 已匹配", msg_id);
                        } else {
                            tracing::debug!("[reply_worker] msg_id={} 无等待者（可能已超时）", msg_id);
                        }
                    });
                }
            }
            Err(e) => {
                tracing::error!("[reply_worker] BRPOP 错误: {}", e);
                tokio::time::sleep(std::time::Duration::from_secs(1)).await;
            }
        }
    }
}