/*
NAME
  descriptor_test.go

DESCRIPTION
  See Readme.md

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

LICENSE
  descriptor_test.go is 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
  along with revid in gpl.txt.  If not, see http://www.gnu.org/licenses.
*/

package psi

import (
	"bytes"
	"testing"
)

const (
	errNotExpectedOut = "Did not get expected output: \ngot : %v, \nwant: %v"
)

var tstPsi1 = PSI{
	Pf:  0x00,
	Tid: 0x02,
	Ssi: true,
	Sl:  0x1c,
	Tss: &TSS{
		Tide: 0x01,
		V:    0,
		Cni:  true,
		Sn:   0,
		Lsn:  0,
		Sd: &PMT{
			Pcrpid: 0x0100, // wrong
			Pil:    10,
			Pd: []Desc{
				{
					Dt: TimeDescTag,
					Dl: TimeDataSize,
					Dd: make([]byte, TimeDataSize),
				},
			},
			Essd: &ESSD{
				St:   0x1b,
				Epid: 0x0100,
				Esil: 0x00,
			},
		},
	},
}

var tstPsi2 = PSI{
	Pf:  0x00,
	Tid: 0x02,
	Ssi: true,
	Sl:  0x12,
	Tss: &TSS{
		Tide: 0x01,
		V:    0,
		Cni:  true,
		Sn:   0,
		Lsn:  0,
		Sd: &PMT{
			Pcrpid: 0x0100,
			Pil:    0,
			Essd: &ESSD{
				St:   0x1b,
				Epid: 0x0100,
				Esil: 0x00,
			},
		},
	},
}

var tstPsi3 = PSI{
	Pf:  0x00,
	Tid: 0x02,
	Ssi: true,
	Sl:  0x3e,
	Tss: &TSS{
		Tide: 0x01,
		V:    0,
		Cni:  true,
		Sn:   0,
		Lsn:  0,
		Sd: &PMT{
			Pcrpid: 0x0100,
			Pil:    PmtTimeLocationPil,
			Pd: []Desc{
				{
					Dt: TimeDescTag,
					Dl: TimeDataSize,
					Dd: make([]byte, TimeDataSize),
				},
				{
					Dt: LocationDescTag,
					Dl: LocationDataSize,
					Dd: make([]byte, LocationDataSize),
				},
			},
			Essd: &ESSD{
				St:   0x1b,
				Epid: 0x0100,
				Esil: 0x00,
			},
		},
	},
}

func TestHasDescriptor(t *testing.T) {
	p := PSIBytes(tstPsi3.Bytes())

	// Try getting descriptor that exists
	_, got := p.HasDescriptor(LocationDescTag)
	want := []byte{
		LocationDescTag,
		LocationDataSize,
	}
	want = append(want, make([]byte, LocationDataSize)...)

	if !bytes.Equal(got, want) {
		t.Errorf(errNotExpectedOut, got, want)
	}

	// Try getting descriptor that doesnt exist
	const fakeTag = 236
	_, got = p.HasDescriptor(fakeTag)
	want = nil

	if !bytes.Equal(got, want) {
		t.Errorf(errNotExpectedOut, got, want)
	}

	// Try getting descriptor from psi that has no descriptors
	p = PSIBytes(tstPsi2.Bytes())

	_, got = p.HasDescriptor(LocationDescTag)
	want = nil

	if !bytes.Equal(got, want) {
		t.Errorf(errNotExpectedOut, got, want)
	}
}

func TestProgramInfoLen(t *testing.T) {
	p := PSIBytes(tstPsi1.Bytes())
	got := p.ProgramInfoLen()
	want := 10
	if got != want {
		t.Errorf(errNotExpectedOut, got, want)
	}
}

func TestDescriptors(t *testing.T) {
	// Try psi with descriptors
	p := PSIBytes(tstPsi1.Bytes())
	got := p.descriptors()
	want := []byte{
		TimeDescTag,
		TimeDataSize,
	}
	want = append(want, make([]byte, TimeDataSize)...)

	if !bytes.Equal(got, want) {
		t.Errorf(errNotExpectedOut, got, want)
	}

	// Now try psi with empty descriptors
	p = PSIBytes(tstPsi2.Bytes())
	got = p.descriptors()
	want = nil
	if !bytes.Equal(got, want) {
		t.Errorf(errNotExpectedOut, got, want)
	}
}

func TestCreateDescriptor(t *testing.T) {
	// Test with PSI containing no descriptors
	p := PSIBytes(tstPsi2.Bytes())
	p.createDescriptor(TimeDescTag, make([]byte, TimeDataSize))
	// update crc
	noPadding := p.trimPadding()
	updateCrc(noPadding[1:])
	want := PSIBytes(tstPsi1.Bytes())
	got := p

	if !bytes.Equal(want, got) {
		t.Errorf(errNotExpectedOut, got, want)
	}

	// Test with psi containing descriptor already
	p = PSIBytes(tstPsi1.Bytes())
	p.createDescriptor(LocationDescTag, make([]byte, LocationDataSize))
	// update crc
	noPadding = p.trimPadding()
	updateCrc(noPadding[1:])
	want = PSIBytes(tstPsi3.Bytes())
	got = p

	if !bytes.Equal(want, got) {
		t.Errorf(errNotExpectedOut, got, want)
	}
}

func TestUpdateDescriptor(t *testing.T) {

}