#include "packet_ring_buffer.h"

#include <algorithm>

namespace rk3588 {

PacketRingBuffer::PacketRingBuffer(int window_sec, int fps_hint) {
    const int sec = std::max(1, window_sec);
    const int fps = std::max(1, fps_hint);
    max_packets_ = static_cast<size_t>(sec * fps);
    if (max_packets_ < 50) max_packets_ = 50;
}

void PacketRingBuffer::Push(std::shared_ptr<EncodedVideoFrameMeta> meta) {
    if (!meta || meta->magic != EncodedVideoFrameMeta::kMagic) return;
    if (meta->pkt.data.empty()) return;
    const int64_t pts_ms = meta->pkt.pts_ms;
    if (pts_ms <= 0) return;

    std::lock_guard<std::mutex> lock(mu_);
    buf_.push_back(Entry{pts_ms, std::move(meta)});
    if (pts_ms > last_pts_ms_) last_pts_ms_ = pts_ms;
    while (buf_.size() > max_packets_) buf_.pop_front();
}

std::vector<std::shared_ptr<EncodedVideoFrameMeta>> PacketRingBuffer::GetPacketsInRange(
    int64_t start_pts_ms, int64_t end_pts_ms) const {
    std::lock_guard<std::mutex> lock(mu_);
    std::vector<std::shared_ptr<EncodedVideoFrameMeta>> out;
    for (const auto& e : buf_) {
        if (e.pts_ms < start_pts_ms) continue;
        if (e.pts_ms > end_pts_ms) break;
        if (e.meta) out.push_back(e.meta);
    }
    return out;
}

int64_t PacketRingBuffer::LatestPtsMs() const {
    std::lock_guard<std::mutex> lock(mu_);
    return last_pts_ms_;
}

size_t PacketRingBuffer::Size() const {
    std::lock_guard<std::mutex> lock(mu_);
    return buf_.size();
}

void PacketRingBuffer::Clear() {
    std::lock_guard<std::mutex> lock(mu_);
    buf_.clear();
    last_pts_ms_ = 0;
}

}  // namespace rk3588