/*
NAME
  client_test.go

DESCRIPTION
  client_test.go provides testing utilities to check RTP client functionality
  provided in client.go.

AUTHOR
  Saxon A. Nelson-Milton <saxon@ausocean.org>

LICENSE
  This is Copyright (C) 2019 the Australian Ocean Lab (AusOcean).

  It is free software: you can redistribute it and/or modify them
  under the terms of the GNU General Public License as published by the
  Free Software Foundation, either version 3 of the License, or (at your
  option) any later version.

  It is distributed in the hope that it will be useful, but WITHOUT
  ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  for more details.

  You should have received a copy of the GNU General Public License
  in gpl.txt.  If not, see http://www.gnu.org/licenses.
*/

package rtp

import (
	"bytes"
	"io"
	"net"
	"testing"
	"time"

	"bitbucket.org/ausocean/utils/logger"
)

// dummyLogger will allow logging to be done by the testing pkg.
type dummyLogger testing.T

func (dl *dummyLogger) log(lvl int8, msg string, args ...interface{}) {
	var l string
	switch lvl {
	case logger.Warning:
		l = "warning"
	case logger.Debug:
		l = "debug"
	case logger.Info:
		l = "info"
	case logger.Error:
		l = "error"
	case logger.Fatal:
		l = "fatal"
	}
	msg = l + ": " + msg
	for i := 0; i < len(args); i++ {
		msg += " %v"
	}
	if len(args) == 0 {
		dl.Log(msg + "\n")
		return
	}
	dl.Logf(msg+"\n", args...)
}

// TestReceiveNoOp will check that we can successfully use a Client to receive
// RTP using no operation.
func TestReceiveNoOp(t *testing.T) {
	const clientAddr = "localhost:8000"
	const packetsToSend = 20

	// Create new client; note that op function set to nil, i.e. we don't want to
	// perform any operation on packet before storing in ringbuffer.
	c, err := NewClient(clientAddr, nil, (*dummyLogger)(t).log, 1*time.Millisecond)
	if err != nil {
		t.Fatalf("could not create client, failed with error: %v", err)
	}
	c.Start()

	// Log any errors from client.
	go func() {
		for {
			err := <-c.ErrChan
			t.Logf("unexpected error from client: %v", err)
		}
	}()

	// Start the RTP 'server'.
	go func() {
		cAddr, err := net.ResolveUDPAddr("udp", clientAddr)
		if err != nil {
			t.Fatalf("could not resolve server address, failed with err: %v", err)
		}

		conn, err := net.DialUDP("udp", nil, cAddr)
		if err != nil {
			t.Fatalf("could not dial udp, failed with err: %v", err)
		}

		// Send packets to the client. Packet payload will just be the packet number.
		for i := 0; i < packetsToSend; i++ {
			p := (&Pkt{V: rtpVer, Payload: []byte{byte(i)}}).Bytes(nil)
			_, err := conn.Write(p)
			if err != nil {
				t.Errorf("could not write packet to conn, failed with err: %v", err)
			}
		}
	}()

	// Read packets using the client and check them with expected.
	var packetsReceived int
	buf := make([]byte, 4096)
	for {
		if packetsReceived == packetsToSend {
			break
		}
		n, err := c.Read(buf)
		switch err {
		case nil:
		case io.EOF:
			continue
		default:
			t.Fatalf("unexpected error: %v", err)
		}
		expect := (&Pkt{V: rtpVer, Payload: []byte{byte(packetsReceived)}}).Bytes(nil)
		got := buf[:n]
		if !bytes.Equal(got, expect) {
			t.Errorf("did not get expected result. \nGot: %v\n Want: %v\n", got, expect)
		}
		packetsReceived++
	}
	c.Stop()
}

func TestReceiveOp(t *testing.T) {

}