#include <algorithm>
#include <algorithm>
#include <cstdint>
#include <string>
#include <vector>

#include "hw/i_image_processor.h"
#include "node.h"
#include "utils/logger.h"

namespace rk3588 {

namespace {

PixelFormat ParseFormat(const std::string& s) {
    if (s == "nv12" || s == "NV12") return PixelFormat::NV12;
    if (s == "yuv420" || s == "YUV420") return PixelFormat::YUV420;
    if (s == "rgb" || s == "RGB") return PixelFormat::RGB;
    if (s == "bgr" || s == "BGR") return PixelFormat::BGR;
    return PixelFormat::UNKNOWN;
}

}  // namespace

class PreprocessNode : public INode {
public:
    std::string Id() const override { return id_; }
    std::string Type() const override { return "preprocess"; }

    bool Init(const SimpleJson& config, const NodeContext& ctx) override {
        id_ = config.ValueOr<std::string>("id", "preprocess");
        dst_w_ = config.ValueOr<int>("dst_w", 640);
        dst_h_ = config.ValueOr<int>("dst_h", 640);
        keep_ratio_ = config.ValueOr<bool>("keep_ratio", false);

        std::string fmt_str = config.ValueOr<std::string>("dst_format", "");
        if (!fmt_str.empty()) {
            dst_fmt_ = ParseFormat(fmt_str);
        }

        const bool requested_use_rga = config.ValueOr<bool>("use_rga", true);
        use_rga_ = requested_use_rga;

        if (const SimpleJson* dbg = config.Find("debug"); dbg && dbg->IsObject()) {
            stats_log_ = dbg->ValueOr<bool>("stats", stats_log_);
            stats_interval_ = std::max<uint64_t>(
                1, static_cast<uint64_t>(dbg->ValueOr<int>("stats_interval", static_cast<int>(stats_interval_))));
        }

        input_queue_ = ctx.input_queue;
        if (!input_queue_) {
            LogError("[preprocess] no input queue for node " + id_);
            return false;
        }
        if (ctx.output_queues.empty()) {
            LogError("[preprocess] no output queue for node " + id_);
            return false;
        }
        output_queues_ = ctx.output_queues;

#if !defined(RK3588_ENABLE_RGA)
        if (requested_use_rga) {
            LogError("[preprocess] use_rga=true but RGA not enabled at build time");
            return false;
        }
        use_rga_ = false;
#endif
#if !defined(RK3588_ENABLE_FFMPEG)
        if (!use_rga_) {
            LogError("[preprocess] neither RGA nor FFmpeg enabled");
            return false;
        }
#endif

        image_processor_ = ctx.image_processor;
        if (!image_processor_) {
            LogError("[preprocess] no image processor for node " + id_);
            return false;
        }

        return true;
    }

    bool Start() override {
        LogInfo("[preprocess] start id=" + id_ + " dst=" + std::to_string(dst_w_) + "x" +
                std::to_string(dst_h_) + (use_rga_ ? " (rga)" : " (swscale)"));
        return true;
    }

    void Stop() override {}

    NodeStatus Process(FramePtr frame) override {
        if (!frame) return NodeStatus::DROP;
        if (!image_processor_) return NodeStatus::ERROR;

        PixelFormat out_fmt = (dst_fmt_ != PixelFormat::UNKNOWN) ? dst_fmt_ : frame->format;
        int out_w = dst_w_;
        int out_h = dst_h_;

        if (out_w <= 0) out_w = frame->width;
        if (out_h <= 0) out_h = frame->height;

        if (keep_ratio_ && dst_w_ > 0 && dst_h_ > 0 && frame->width > 0 && frame->height > 0) {
            float scale = std::min(static_cast<float>(dst_w_) / frame->width,
                                   static_cast<float>(dst_h_) / frame->height);
            out_w = static_cast<int>(frame->width * scale);
            out_h = static_cast<int>(frame->height * scale);
            out_w = (out_w + 1) & ~1;
            out_h = (out_h + 1) & ~1;
        }

        const bool need_resize = (frame->width != out_w || frame->height != out_h);
        const bool need_cvt = (frame->format != out_fmt);

        if (need_resize) {
            WarnMetaResizeOnce(frame, out_w, out_h);
        }

        if (!need_resize && !need_cvt) {
            ProcessPassthrough(frame);
            return NodeStatus::OK;
        }

        Frame out;
        out.width = out_w;
        out.height = out_h;
        out.format = out_fmt;

        Status st = image_processor_->Resize(*frame, out);
        if (st.Failed()) {
            if (!use_rga_ && st.ErrMessage().find("unsupported format") != std::string::npos) {
                ProcessPassthrough(frame);
                return NodeStatus::OK;
            }
            LogError("[preprocess] " + st.ErrMessage());
            return NodeStatus::ERROR;
        }

        auto out_frame = std::make_shared<Frame>(out);
        out_frame->pts = frame->pts;
        out_frame->frame_id = frame->frame_id;
        out_frame->det = frame->det;
        out_frame->face_det = frame->face_det;
        out_frame->face_recog = frame->face_recog;
        out_frame->user_meta = frame->user_meta;

        PushToDownstream(out_frame);
        ++processed_;

        if (stats_log_ && stats_interval_ > 0 && (processed_ % stats_interval_) == 0) {
            LogInfo("[preprocess] " + std::string(use_rga_ ? "rga" : "swscale") +
                    " frame=" + std::to_string(out_frame->frame_id) +
                    " " + std::to_string(frame->width) + "x" + std::to_string(frame->height) +
                    " -> " + std::to_string(out_w) + "x" + std::to_string(out_h) +
                    " id=" + id_);
        }

        return NodeStatus::OK;
    }

private:
    void PushToDownstream(FramePtr frame) {
        for (auto& q : output_queues_) {
            q->Push(frame);
        }
    }

    void WarnMetaResizeOnce(const FramePtr& frame, int out_w, int out_h) {
        if (warned_meta_resize_) return;
        if (!frame) return;
        if (frame->width == out_w && frame->height == out_h) return;
        if (!frame->det && !frame->face_det && !frame->face_recog) return;
        warned_meta_resize_ = true;
        LogWarn("[preprocess] resized frame but forwarded det/face meta without coordinate scaling; ensure det/recog/osd use same resolution (id=" + id_ + ")");
    }

    void ProcessPassthrough(FramePtr frame) {
        PushToDownstream(frame);
        ++processed_;
        if (stats_log_ && stats_interval_ > 0 && (processed_ % stats_interval_) == 0) {
            LogInfo("[preprocess] passthrough frame=" + std::to_string(frame->frame_id) + " id=" + id_);
        }
    }

    std::string id_;
    int dst_w_ = 640;
    int dst_h_ = 640;
    bool keep_ratio_ = false;
    PixelFormat dst_fmt_ = PixelFormat::UNKNOWN;
    bool use_rga_ = true;

    bool stats_log_ = false;
    uint64_t stats_interval_ = 100;

    bool warned_meta_resize_ = false;

    std::shared_ptr<SpscQueue<FramePtr>> input_queue_;
    std::vector<std::shared_ptr<SpscQueue<FramePtr>>> output_queues_;
    std::shared_ptr<IImageProcessor> image_processor_;
    uint64_t processed_ = 0;
};

REGISTER_NODE(PreprocessNode, "preprocess");

}  // namespace rk3588