/*
DESCRIPTION
  nalunit_test.go provides testing for functionality in nalunit.go.

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

LICENSE
  Copyright (C) 2017-2019 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 h264dec

import (
	"bytes"
	"reflect"
	"testing"

	"bitbucket.org/ausocean/av/codec/h264/h264dec/bits"
)

func TestNewMVCExtension(t *testing.T) {
	tests := []struct {
		in   string
		want *MVCExtension
		err  error
	}{
		{
			in: "0" + // u(1) non_idr_flag = false
				"00 0010" + // u(6) priority_id = 2
				"00 0001 1000" + // u(10) view_id = 24
				"100" + // u(3) temporal_id = 4
				"1" + // u(1) anchor_pic_flag = true
				"0" + // u(1) inter_view_flag = false
				"1" + // u(1) reserved_one_bit = 1
				"0", // Some padding
			want: &MVCExtension{
				NonIdrFlag:     false,
				PriorityID:     2,
				ViewID:         24,
				TemporalID:     4,
				AnchorPicFlag:  true,
				InterViewFlag:  false,
				ReservedOneBit: 1,
			},
		},
	}

	for i, test := range tests {
		inBytes, err := binToSlice(test.in)
		if err != nil {
			t.Fatalf("did not expect error %v from binToSlice for test %d", err, i)
		}

		got, err := NewMVCExtension(bits.NewBitReader(bytes.NewReader(inBytes)))
		if err != test.err {
			t.Errorf("did not get expected error for test %d\nGot: %v\nWant: %v\n", i, err, test.err)
		}

		if !reflect.DeepEqual(got, test.want) {
			t.Errorf("did not get expected result for test %d\nGot: %v\nWant: %v\n", i, *got, test.want)
		}
	}
}

func TestNewThreeDAVCExtension(t *testing.T) {
	tests := []struct {
		in   string
		want *ThreeDAVCExtension
		err  error
	}{
		{
			in: "0001 0000" + // u(8) view_idx = 16
				"1" + // u(1) depth_flag = true
				"0" + // u(1) non_idr_flag = false
				"010" + // u(1) temporal_id = 2
				"1" + // u(1) anchor_pic_flag = true
				"1" + // u(1) inter_view_flag = true
				"000", // Some padding
			want: &ThreeDAVCExtension{
				ViewIdx:       16,
				DepthFlag:     true,
				NonIdrFlag:    false,
				TemporalID:    2,
				AnchorPicFlag: true,
				InterViewFlag: true,
			},
		},
	}

	for i, test := range tests {
		inBytes, err := binToSlice(test.in)
		if err != nil {
			t.Fatalf("did not expect error %v from binToSlice for test %d", err, i)
		}

		got, err := NewThreeDAVCExtension(bits.NewBitReader(bytes.NewReader(inBytes)))
		if err != test.err {
			t.Errorf("did not get expected error for test %d\nGot: %v\nWant: %v\n", i, err, test.err)
		}

		if !reflect.DeepEqual(got, test.want) {
			t.Errorf("did not get expected result for test %d\nGot: %v\nWant: %v\n", i, *got, test.want)
		}
	}
}

func TestSVCExtension(t *testing.T) {
	tests := []struct {
		in   string
		want *SVCExtension
		err  error
	}{
		{
			in: "0" + // u(1) idr_flag = false
				"10 0000" + // u(6) priority_id = 32
				"0" + // u(1) no_inter_layer_pred_flag = false
				"001" + // u(3) dependency_id = 1
				"1000" + // u(4) quality_id = 8
				"010" + // u(3) temporal_id = 2
				"1" + // u(1) use_ref_base_pic_flag = true
				"0" + // u(1) discardable_flag = false
				"0" + // u(1) output_flag = false
				"11" + // ReservedThree2Bits
				"0", // padding
			want: &SVCExtension{
				IdrFlag:              false,
				PriorityID:           32,
				NoInterLayerPredFlag: false,
				DependencyID:         1,
				QualityID:            8,
				TemporalID:           2,
				UseRefBasePicFlag:    true,
				DiscardableFlag:      false,
				OutputFlag:           false,
				ReservedThree2Bits:   3,
			},
		},
	}

	for i, test := range tests {
		inBytes, err := binToSlice(test.in)
		if err != nil {
			t.Fatalf("did not expect error %v from binToSlice for test %d", err, i)
		}

		got, err := NewSVCExtension(bits.NewBitReader(bytes.NewReader(inBytes)))
		if err != test.err {
			t.Errorf("did not get expected error for test %d\nGot: %v\nWant: %v\n", i, err, test.err)
		}

		if !reflect.DeepEqual(got, test.want) {
			t.Errorf("did not get expected result for test %d\nGot: %v\nWant: %v\n", i, *got, test.want)
		}
	}
}

func TestNewNALUnit(t *testing.T) {
	tests := []struct {
		in   string
		want *NALUnit
		err  error
	}{
		{
			in: "0" + // f(1) forbidden_zero_bit = 0
				"01" + // u(2) nal_ref_idc = 1
				"0 1110" + // u(5) nal_unit_type = 14
				"1" + // u(1) svc_extension_flag = true

				// svc extension
				"0" + // u(1) idr_flag = false
				"10 0000" + // u(6) priority_id = 32
				"0" + // u(1) no_inter_layer_pred_flag = false
				"001" + // u(3) dependency_id = 1
				"1000" + // u(4) quality_id = 8
				"010" + // u(3) temporal_id = 2
				"1" + // u(1) use_ref_base_pic_flag = true
				"0" + // u(1) discardable_flag = false
				"0" + // u(1) output_flag = false
				"11" + // ReservedThree2Bits

				// rbsp bytes
				"0000 0001" +
				"0000 0010" +
				"0000 0100" +
				"0000 1000" +
				"1000 0000", // trailing bits

			want: &NALUnit{
				ForbiddenZeroBit: 0,
				RefIdc:           1,
				Type:             14,
				SVCExtensionFlag: true,
				SVCExtension: &SVCExtension{
					IdrFlag:              false,
					PriorityID:           32,
					NoInterLayerPredFlag: false,
					DependencyID:         1,
					QualityID:            8,
					TemporalID:           2,
					UseRefBasePicFlag:    true,
					DiscardableFlag:      false,
					OutputFlag:           false,
					ReservedThree2Bits:   3,
				},

				RBSP: []byte{
					0x01,
					0x02,
					0x04,
					0x08,
				},
			},
		},
	}

	for i, test := range tests {
		inBytes, err := binToSlice(test.in)
		if err != nil {
			t.Fatalf("did not expect error %v from binToSlice for test %d", err, i)
		}

		got, err := NewNALUnit(bits.NewBitReader(bytes.NewReader(inBytes)))
		if err != test.err {
			t.Errorf("did not get expected error for test %d\nGot: %v\nWant: %v\n", i, err, test.err)
		}

		if !nalEqual(got, test.want) {
			t.Errorf("did not get expected result for test %d\nGot: %v\nWant: %v\n", i, *got, test.want)
		}
	}
}

// nalEqual returns true if two NALUnits are equal.
func nalEqual(a, b *NALUnit) bool {
	aCopy := nalWithoutExtensions(*a)
	bCopy := nalWithoutExtensions(*b)

	if !reflect.DeepEqual(aCopy, bCopy) {
		return false
	}

	if (a.SVCExtension == nil || b.SVCExtension == nil) &&
		(a.SVCExtension != b.SVCExtension) {
		return false
	}

	if (a.MVCExtension == nil || b.MVCExtension == nil) &&
		(a.MVCExtension != b.MVCExtension) {
		return false
	}

	if (a.ThreeDAVCExtension == nil || b.ThreeDAVCExtension == nil) &&
		(a.ThreeDAVCExtension != b.ThreeDAVCExtension) {
		return false
	}

	if !reflect.DeepEqual(a.SVCExtension, b.SVCExtension) ||
		!reflect.DeepEqual(a.MVCExtension, b.MVCExtension) ||
		!reflect.DeepEqual(a.ThreeDAVCExtension, b.ThreeDAVCExtension) {
		return false
	}
	return true
}

func nalWithoutExtensions(n NALUnit) NALUnit {
	n.SVCExtension = nil
	n.MVCExtension = nil
	n.ThreeDAVCExtension = nil
	return n
}