package webrtc

import (
	"github.com/pion/rtp"
	"github.com/pion/webrtc/v4"
)

// forwardRTP reads packets from sub and writes them to the correct track
// based on payload type (H.264 → video, Opus → audio). Payload-type
// inspection is the simplest M1 approach; M2 will switch to per-track
// source channels once the process resolver manages separate video/audio
// UDP ports.
func forwardRTP(done <-chan struct{}, sub <-chan *rtp.Packet,
	video, audio *webrtc.TrackLocalStaticRTP) {
	for {
		select {
		case <-done:
			return
		case pkt, ok := <-sub:
			if !ok {
				return
			}
			// Pion default H.264 PT = 102, Opus PT = 111. If the publisher
			// uses different PTs we'll revisit in M2 — for M1 PoC we
			// configure FFmpeg to these values explicitly in the publisher
			// script.
			switch pkt.PayloadType {
			case 102:
				_ = video.WriteRTP(pkt)
			case 111:
				_ = audio.WriteRTP(pkt)
			default:
				// Unknown PT — drop. Log in M3.
			}
		}
	}
}