package gateway

import (
	"context"
	"net"
	"testing"
	"time"
)

func TestGatewaySlowReaderStillCleansUpWithinBound(t *testing.T) {
	harness := newGatewayTransportHarness(t)
	for sequence := 0; sequence < 10_000; sequence++ {
		harness.session.EmitVideo([]byte{byte(sequence)})
	}
	if err := harness.client.Close(); err != nil {
		t.Fatal(err)
	}
	harness.waitReleased(t)
}

func TestGatewayDropsVideoPastQueueResidenceBound(t *testing.T) {
	harness := newGatewayTransportHarness(t)
	harness.drainInitialMedia(t)
	before := harness.server.Metrics().MediaDrops
	harness.session.video <- ProviderMedia{
		Payload: []byte("stale-complete-frame"), ReceivedAt: time.Now().Add(-time.Second),
		EnqueuedAt: time.Now().Add(-nativeApolloVideoQueueLatency - time.Millisecond),
	}
	ctx, cancel := context.WithTimeout(context.Background(), 150*time.Millisecond)
	defer cancel()
	if frame, err := harness.client.ReceiveFrame(ctx); err == nil {
		t.Fatalf("expired provider frame crossed the public transport: %#v", frame)
	}
	if drops := harness.server.Metrics().MediaDrops - before; drops != 1 {
		t.Fatalf("expired queue drops = %d, want 1", drops)
	}
}

func TestGatewayMalformedUDPDoesNotAmplify(t *testing.T) {
	harness := newGatewayTransportHarness(t)
	connection, err := net.DialUDP("udp", nil, harness.server.Addr().(*net.UDPAddr))
	if err != nil {
		t.Fatal(err)
	}
	defer connection.Close()
	request := []byte("invalid")
	if _, err := connection.Write(request); err != nil {
		t.Fatal(err)
	}
	if err := connection.SetReadDeadline(time.Now().Add(100 * time.Millisecond)); err != nil {
		t.Fatal(err)
	}
	response := make([]byte, len(request)*3+1)
	count, _, err := connection.ReadFromUDP(response)
	if err != nil {
		if timeout, ok := err.(net.Error); ok && timeout.Timeout() {
			return
		}
		t.Fatal(err)
	}
	if count > len(request)*3 {
		t.Fatalf("malformed UDP amplified %d bytes to %d", len(request), count)
	}
}