package main

import (
	"fmt"
	"math"
	"testing"

	"github.com/pion/rtp"
	"gopkg.in/hraban/opus.v2"
)

func TestPadding(t *testing.T) {
	for _, name := range []string{"empty payload", "other payload type"} {
		enc, _ := opus.NewEncoder(rate, channels, opus.AppAudio)
		dec, _ := opus.NewDecoder(rate, channels)
		jb := newJitterBuffer(dec, 111)
		pcm := make([]int16, frameSamps*channels)
		buf := make([]byte, 4000)
		seq, ts := uint16(0), 0.0
		frames := 0
		// 10 minutes of playout; audio packet every 20 ms, plus a padding packet every 40 seqs.
		for tms := 0.0; tms < 600000; tms += 20 {
			for ts <= tms {
				if seq%40 == 39 {
					p := &rtp.Packet{Header: rtp.Header{SequenceNumber: seq, PayloadType: 111}}
					if name != "empty payload" {
						p.PayloadType, p.Payload = 13, []byte{0x40}
					}
					jb.push(p)
					seq++
					continue
				}
				for k := range pcm { pcm[k] = int16(6000 * math.Sin(float64(frames*frameSamps+k/2)*2*math.Pi*220/rate)) }
				n, _ := enc.Encode(pcm, buf)
				jb.push(&rtp.Packet{Header: rtp.Header{SequenceNumber: seq, PayloadType: 111}, Payload: append([]byte(nil), buf[:n]...)})
				seq++; frames++; ts += 20
			}
			jb.next()
		}
		c, d, tg := jb.snapshot()
		fmt.Printf("%-20s padding=%d lost=%d fec=%d concealed=%d drift-drops=%d inserted=%d underruns=%d buffer=%d/%dms\n", name, c.Padding, c.Lost, c.FEC, c.PLC, c.Dropped, c.Inserted, c.Underruns, d, tg)
		if c.Lost+c.PLC+c.Dropped+c.Underruns != 0 { t.Errorf("%s: padding still causes damage", name) }
	}
}