// rtmp_manager.cpp (reliable integrated version)
// - record：启动时由配置决定（静态开关）
// - live：MQTT 动态开关（运行时可变）
// - 关键增强：PLAYING 成功后再“放行 valve”（避免 cold-start mux/sink 饿死）
// - 关键增强：rtmpsink 强制 IPv4（protocol=0），减少偶发握手卡住
// - 关键增强：更严谨的 cleanup + 保存/释放 valve 引用，避免泄漏/悬挂引用

#include "rtmp_manager.hpp"

#include <arpa/inet.h>
#include <ifaddrs.h>
#include <netinet/in.h>
#include <sys/stat.h>

#include <chrono>
#include <cstring>
#include <memory>
#include <thread>

std::atomic<bool> RTMPManager::g_live_enabled{false};
// record 是“启动时决定一次”的静态开关：由 config.json 决定
bool RTMPManager::g_record_enabled = true;

// =======================================================
// 工具函数
// =======================================================
static bool device_exists(const std::string& path)
{
    struct stat st;
    return stat(path.c_str(), &st) == 0;
}

// 获取指定网卡 IPv4
std::string get_ip_address(const std::string& ifname)
{
    struct ifaddrs* ifaddr = nullptr;
    if (getifaddrs(&ifaddr) != 0) return "";

    char ip[INET_ADDRSTRLEN] = {0};
    for (auto* ifa = ifaddr; ifa; ifa = ifa->ifa_next)
    {
        if (!ifa->ifa_addr) continue;
        if (ifa->ifa_addr->sa_family == AF_INET && ifname == ifa->ifa_name)
        {
            auto* addr = &reinterpret_cast<sockaddr_in*>(ifa->ifa_addr)->sin_addr;
            inet_ntop(AF_INET, addr, ip, sizeof(ip));
            break;
        }
    }

    freeifaddrs(ifaddr);
    return ip;
}

// 安全释放 GstObject*
static void safe_unref(GstObject*& obj)
{
    if (obj)
    {
        gst_object_unref(obj);
        obj = nullptr;
    }
}

// 安全设置 GStreamer 属性：有则设，无则跳过
static void try_set_property(GstElement* elem, const char* prop, int value)
{
    if (!elem) return;

    GObjectClass* klass = G_OBJECT_GET_CLASS(elem);
    if (klass && g_object_class_find_property(klass, prop))
    {
        g_object_set(G_OBJECT(elem), prop, value, nullptr);
        LOG_INFO(std::string("[RTMP] Set ") + GST_ELEMENT_NAME(elem) + "." + prop + "=" + std::to_string(value));
    }
    else
    {
        LOG_WARN(std::string("[RTMP] ") + GST_ELEMENT_NAME(elem) + " has NO property '" + prop + "' (skip)");
    }
}

// =======================================================
// 静态成员
// =======================================================
std::unordered_map<std::string, std::unique_ptr<RTMPManager::StreamContext>> RTMPManager::streams;
std::mutex RTMPManager::streams_mutex;

// =======================================================
// 初始化
// =======================================================
void RTMPManager::init()
{
    gst_init(nullptr, nullptr);
    LOG_INFO("[RTMP] GStreamer initialized");
}

std::string RTMPManager::make_key(const std::string& name) { return name + "_main"; }

// =======================================================
// 创建推流管线（稳定版）
// =======================================================
GstElement* RTMPManager::create_pipeline(const Camera& cam)
{
    const std::string stream = cam.name + "_main";
    const std::string app = "camera";

    // 维持你当前 SRS 的 vhost query 方式，避免改动联动太多
    const std::string live_rtmp = "rtmp://36.153.162.171:19435/" + app + "/" + stream + "?vhost=live";
    const std::string record_rtmp = "rtmp://127.0.0.1:2935/" + app + "/" + stream + "?vhost=record";

    // 关键：rtmpsink protocol=0 强制 IPv4（减少握手卡住/IPv6 干扰）
    // 关键：valve 默认 drop=true，真正放行在 PLAYING 成功后再做（避免 cold-start 饿死）
    std::string pipeline_str = "v4l2src device=" + cam.device +
                               " io-mode=dmabuf "
                               "! video/x-raw,format=NV12,width=1920,height=1080,framerate=" +
                               std::to_string(cam.fps) +
                               "/1 "
                               "! videoscale "
                               "! video/x-raw,width=" +
                               std::to_string(cam.width) + ",height=" + std::to_string(cam.height) +
                               " "
                               "! queue max-size-buffers=2 leaky=downstream "
                               "! mpph264enc rc-mode=cbr bps=" +
                               std::to_string(cam.bitrate) + " gop=" + std::to_string(cam.fps) +
                               " header-mode=each-idr profile=baseline "
                               "! h264parse config-interval=1 "
                               "! tee name=t "

                               // ===== record branch =====
                               "t. ! queue max-size-buffers=8 leaky=downstream "
                               "! valve name=record_valve drop=true "
                               "! queue max-size-buffers=8 leaky=downstream "
                               "! flvmux name=rec_mux streamable=true "
                               "! rtmpsink name=rec_sink location=\"" +
                               record_rtmp +
                               "\" sync=false async=false "

                               // ===== live branch =====
                               "t. ! queue max-size-buffers=8 leaky=downstream "
                               "! valve name=live_valve drop=true "
                               "! queue max-size-buffers=8 leaky=downstream "
                               "! flvmux name=live_mux streamable=true "
                               "! rtmpsink name=live_sink location=\"" +
                               live_rtmp + "\" sync=false async=false ";

    GError* err = nullptr;
    GstElement* pipeline = gst_parse_launch(pipeline_str.c_str(), &err);
    if (err)
    {
        LOG_ERROR("[RTMP] Pipeline creation failed: " + std::string(err->message));
        g_error_free(err);
        return nullptr;
    }

    return pipeline;
}

// =======================================================
// 主推流线程
// =======================================================
void RTMPManager::stream_loop(Camera cam, StreamContext* ctx)
{
    const std::string key = make_key(cam.name);

    auto mark_error = [&](const std::string& err)
    {
        std::lock_guard<std::mutex> lk(ctx->status_mutex);
        ctx->status.running = false;
        ctx->status.last_error = err;
    };

    while (ctx->thread_running)
    {
        // 1) 设备存在性
        if (!device_exists(cam.device))
        {
            mark_error("Device not found: " + cam.device);
            LOG_WARN("[RTMP] " + key + " - device not found");
            std::this_thread::sleep_for(std::chrono::seconds(3));
            continue;
        }

        // 2) 创建 pipeline
        GstElement* pipeline = create_pipeline(cam);
        if (!pipeline)
        {
            mark_error("Pipeline creation failed");
            std::this_thread::sleep_for(std::chrono::seconds(3));
            continue;
        }

        // 2.1) 获取 valve（保存到 ctx，供 MQTT 动态控制 live，record 启动静态决定）
        GstElement* live_valve = gst_bin_get_by_name(GST_BIN(pipeline), "live_valve");
        GstElement* record_valve = gst_bin_get_by_name(GST_BIN(pipeline), "record_valve");

        // ===== 获取 rec_sink / live_sink =====
        GstElement* rec_sink = gst_bin_get_by_name(GST_BIN(pipeline), "rec_sink");
        GstElement* live_sink = gst_bin_get_by_name(GST_BIN(pipeline), "live_sink");

        // ===== 尝试设置 protocol=0（兼容：有就设，无就跳过）=====
        try_set_property(rec_sink, "protocol", 0);
        try_set_property(live_sink, "protocol", 0);

        // ===== 引用使用完就释放（不交给 ctx 管理）=====
        if (rec_sink) gst_object_unref(rec_sink);
        if (live_sink) gst_object_unref(live_sink);

        if (!live_valve || !record_valve)
        {
            if (!live_valve) LOG_ERROR("[RTMP] " + key + " - live_valve not found");
            if (!record_valve) LOG_ERROR("[RTMP] " + key + " - record_valve not found");
            mark_error("valve not found");

            if (live_valve) gst_object_unref(live_valve);
            if (record_valve) gst_object_unref(record_valve);
            gst_object_unref(pipeline);
            std::this_thread::sleep_for(std::chrono::seconds(3));
            continue;
        }

        {
            std::lock_guard<std::mutex> lk(ctx->status_mutex);
            // 替换旧引用（避免泄漏）
            if (ctx->live_valve) gst_object_unref(ctx->live_valve);
            if (ctx->record_valve) gst_object_unref(ctx->record_valve);

            ctx->live_valve = live_valve;      // 引用交给 ctx 管理
            ctx->record_valve = record_valve;  // 引用交给 ctx 管理
        }

        // 2.2) 启动前：统一先 drop=true（不放行）
        //      真正放行在 PLAYING 确认后进行（关键稳定性增强）
        g_object_set(G_OBJECT(live_valve), "drop", TRUE, nullptr);
        g_object_set(G_OBJECT(record_valve), "drop", TRUE, nullptr);

        GstBus* bus = gst_element_get_bus(pipeline);

        LOG_INFO("[RTMP] Starting stream: " + key);
        gst_element_set_state(pipeline, GST_STATE_PLAYING);

        // 3) 等待进入 PLAYING
        GstState state = GST_STATE_NULL;
        auto ret = gst_element_get_state(pipeline, &state, nullptr, 5 * GST_SECOND);
        if (!(ret == GST_STATE_CHANGE_SUCCESS && state == GST_STATE_PLAYING))
        {
            mark_error("Failed to reach PLAYING");
            LOG_ERROR("[RTMP] " + key + " failed to PLAY");
            goto cleanup;
        }

        // 4) PLAYING 成功后，稍微延迟再按最终策略放行 valve（关键稳定性增强）
        std::this_thread::sleep_for(std::chrono::milliseconds(150));

        // record：启动时决定一次（静态开关）
        g_object_set(G_OBJECT(record_valve), "drop", g_record_enabled ? FALSE : TRUE, nullptr);

        // live：运行期由 MQTT 控制（动态开关），此处按当前全局状态设置初值
        g_object_set(G_OBJECT(live_valve), "drop", g_live_enabled.load() ? FALSE : TRUE, nullptr);

        {
            std::lock_guard<std::mutex> lk(ctx->status_mutex);
            ctx->status.running = true;
            ctx->status.last_error.clear();
        }
        LOG_INFO("[RTMP] " + key + " confirmed PLAYING");

        // 5) 正常运行：监听 ERROR / EOS
        while (ctx->thread_running)
        {
            GstMessage* msg = gst_bus_timed_pop_filtered(
                bus, 300 * GST_MSECOND, static_cast<GstMessageType>(GST_MESSAGE_ERROR | GST_MESSAGE_EOS));

            if (!msg)
            {
                // 心跳：能跑就认为 running
                std::lock_guard<std::mutex> lk(ctx->status_mutex);
                ctx->status.running = true;
                continue;
            }

            if (GST_MESSAGE_TYPE(msg) == GST_MESSAGE_ERROR)
            {
                GError* err = nullptr;
                gst_message_parse_error(msg, &err, nullptr);

                mark_error(err ? err->message : "Unknown GStreamer error");
                LOG_ERROR("[RTMP] " + key + " ERROR: " + (err ? err->message : "unknown"));

                if (err) g_error_free(err);
                gst_message_unref(msg);
                break;
            }

            if (GST_MESSAGE_TYPE(msg) == GST_MESSAGE_EOS)
            {
                mark_error("EOS");
                LOG_WARN("[RTMP] " + key + " EOS");
                gst_message_unref(msg);
                break;
            }

            gst_message_unref(msg);
        }

    cleanup:
        // 6) 清理：先释放 ctx 保存的 valve 引用（避免下一轮使用旧引用）
        {
            std::lock_guard<std::mutex> lk(ctx->status_mutex);
            if (ctx->live_valve)
            {
                gst_object_unref(ctx->live_valve);
                ctx->live_valve = nullptr;
            }
            if (ctx->record_valve)
            {
                gst_object_unref(ctx->record_valve);
                ctx->record_valve = nullptr;
            }
        }

        // 7) pipeline 清理
        gst_element_set_state(pipeline, GST_STATE_NULL);
        if (bus) gst_object_unref(bus);
        gst_object_unref(pipeline);

        if (ctx->thread_running)
        {
            LOG_WARN("[RTMP] Restarting " + key + " in 3s...");
            std::this_thread::sleep_for(std::chrono::seconds(3));
        }
    }

    {
        std::lock_guard<std::mutex> lk(ctx->status_mutex);
        ctx->status.running = false;
    }
    LOG_INFO("[RTMP] Stream thread exited for " + key);
}

// =======================================================
// 启停管理
// =======================================================
void RTMPManager::start_all()
{
    LOG_INFO("[RTMP] Starting enabled streams...");
    std::lock_guard<std::mutex> lock(streams_mutex);

    int delay_ms = 0;
    for (const auto& cam : g_app_config.cameras)
    {
        if (!cam.enabled)
        {
            LOG_INFO("[RTMP] Skip disabled camera: " + cam.name);
            continue;
        }

        const auto key = make_key(cam.name);
        if (streams.count(key)) continue;

        auto ctx = std::make_unique<StreamContext>();
        ctx->thread_running.store(true);

        ctx->thread = std::thread(
            [cam, ptr = ctx.get(), delay_ms]()
            {
                std::this_thread::sleep_for(std::chrono::milliseconds(delay_ms));
                stream_loop(cam, ptr);
            });

        streams.emplace(key, std::move(ctx));
        delay_ms += 200;
    }
}

void RTMPManager::stop_all()
{
    std::lock_guard<std::mutex> lock(streams_mutex);

    for (auto& kv : streams)
    {
        kv.second->thread_running.store(false);

        std::lock_guard<std::mutex> lk(kv.second->status_mutex);

        if (kv.second->live_valve)
        {
            gst_object_unref(kv.second->live_valve);
            kv.second->live_valve = nullptr;
        }
        if (kv.second->record_valve)
        {
            gst_object_unref(kv.second->record_valve);
            kv.second->record_valve = nullptr;
        }
    }

    for (auto& kv : streams)
        if (kv.second->thread.joinable()) kv.second->thread.join();

    streams.clear();
}

// =======================================================
// 状态 & URL
// =======================================================
bool RTMPManager::is_streaming(const std::string& cam_name)
{
    std::lock_guard<std::mutex> lock(streams_mutex);
    auto it = streams.find(make_key(cam_name));
    if (it == streams.end()) return false;

    std::lock_guard<std::mutex> lk(it->second->status_mutex);
    return it->second->status.running;
}

std::string RTMPManager::get_stream_url(const std::string& cam_name)
{
    std::string ip = get_ip_address("enP2p33s0");
    if (ip.empty()) ip = "192.168.4.194";

    return "http://" + ip + ":11985/rtc/v1/whep/?app=camera&stream=" + cam_name + "_main&vhost=live";
}

// =======================================================
// 汇总状态
// =======================================================
std::vector<RTMPManager::ChannelInfo> RTMPManager::get_all_channels_status()
{
    std::vector<ChannelInfo> result;
    std::lock_guard<std::mutex> lock(streams_mutex);

    for (size_t i = 0; i < g_app_config.cameras.size(); ++i)
    {
        const auto& cam = g_app_config.cameras[i];
        ChannelInfo ch{};
        ch.loc = static_cast<int>(i);

        if (!cam.enabled)
        {
            ch.running = false;
            ch.reason = "Disabled by config";
            result.push_back(ch);
            continue;
        }

        auto it = streams.find(make_key(cam.name));
        if (it != streams.end())
        {
            std::lock_guard<std::mutex> lk(it->second->status_mutex);
            ch.running = it->second->status.running;
            ch.reason = it->second->status.last_error;
            if (ch.running) ch.url = get_stream_url(cam.name);
        }
        else
        {
            ch.running = false;
            ch.reason = "Not started";
        }

        result.push_back(ch);
    }

    return result;
}

// =======================================================
// live：MQTT 动态开关
// =======================================================
void RTMPManager::set_live_enabled_all(bool enable)
{
    std::lock_guard<std::mutex> lock(streams_mutex);

    g_live_enabled.store(enable);

    for (auto& kv : streams)
    {
        auto* ctx = kv.second.get();
        std::lock_guard<std::mutex> lk(ctx->status_mutex);
        if (!ctx->live_valve) continue;

        // enable=true → drop=false（放行 live）
        g_object_set(G_OBJECT(ctx->live_valve), "drop", enable ? FALSE : TRUE, nullptr);
    }

    LOG_INFO(std::string("[RTMP] Live ") + (enable ? "ENABLED" : "DISABLED") + " for all streams");
}

void RTMPManager::set_live_enabled(const std::string& cam_name, bool enable)
{
    std::lock_guard<std::mutex> lock(streams_mutex);
    auto it = streams.find(make_key(cam_name));
    if (it == streams.end()) return;

    auto* ctx = it->second.get();
    std::lock_guard<std::mutex> lk(ctx->status_mutex);
    if (!ctx->live_valve) return;

    g_object_set(G_OBJECT(ctx->live_valve), "drop", enable ? FALSE : TRUE, nullptr);
    LOG_INFO("[RTMP] Live " + std::string(enable ? "ENABLED" : "DISABLED") + " for " + cam_name);
}