/*
DESCRIPTION
  file_test.go provides testing for functionality contained in file.go.

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

LICENSE
  Copyright (C) 2022-2023 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 main

import (
	"bytes"
	"encoding/json"
	"reflect"
	"testing"

	"bitbucket.org/ausocean/av/cmd/vidforward/global"
	"bitbucket.org/ausocean/av/revid"
	"bitbucket.org/ausocean/av/revid/config"
	"bitbucket.org/ausocean/utils/logging"
)

const (
	testURL = "rtmp://some-random-url.abcdef-12345"
	testMAC = "78:90:AE:7B:2C:76"
)

func init() {
	inTest = true
}

func TestBroadcastMarshal(t *testing.T) {
	logger := (*logging.TestLogger)(t)

	// Marshalling functionality uses this.
	global.SetLogger(logger)

	tests := []struct {
		in     Broadcast
		expect []byte
	}{
		{
			in: Broadcast{
				mac:    testMAC,
				urls:   []string{testURL},
				status: statusActive,
				rv:     newRevidForTest((*logging.TestLogger)(t), testURL, t),
			},
			expect: []byte("{\"MAC\":\"" + testMAC + "\",\"URLs\":[\"" + testURL + "\"],\"Status\":\"" + statusActive + "\"}"),
		},
	}

	for i, test := range tests {
		got, err := test.in.MarshalJSON()
		if err != nil {
			t.Errorf("could not marshal json for test no. %d: %v", i, err)
			continue
		}
		if !bytes.Equal(got, test.expect) {
			t.Errorf("did not get expected result.\nGot: %v\nWnt: %v\n", string(got), string(test.expect))
		}
	}
}

func TestBroadcastUnmarshal(t *testing.T) {
	logger := (*logging.TestLogger)(t)

	// Marshalling functionality uses this.
	global.SetLogger(logger)

	tests := []struct {
		in     []byte
		expect *Broadcast
	}{
		{
			expect: &Broadcast{
				mac:    testMAC,
				urls:   []string{testURL},
				status: statusActive,
				rv:     newRevidForTest(logger, testURL, t),
			},
			in: []byte("{\"MAC\":\"" + testMAC + "\",\"URLs\":[\"" + testURL + "\"],\"Status\":\"" + statusActive + "\"}"),
		},
	}

	for i, test := range tests {
		var got Broadcast
		err := got.UnmarshalJSON(test.in)
		if err != nil {
			t.Errorf("could not marshal json for test no. %d: %v", i, err)
			continue
		}
		if !broadcastsEqual(&got, test.expect) {
			t.Errorf("did not get expected result.\nGot: %v\nWnt: %v\n", got, test.expect)
		}
	}
}

func TestBroadcastManagerMarshal(t *testing.T) {
	logger := (*logging.TestLogger)(t)

	// Marshalling functionality uses this.
	global.SetLogger(logger)

	tests := []struct {
		in     broadcastManager
		expect []byte
	}{
		{
			in: broadcastManager{
				broadcasts: map[MAC]*Broadcast{
					testMAC: &Broadcast{
						testMAC,
						[]string{testURL},
						statusSlate,
						newRevidForTest((*logging.TestLogger)(t), testURL, t),
					},
				},
				slateExitSignals: newExitSignalsForTest(t, testMAC),
				log:              logger,
				dogNotifier:      newWatchdogNotifierForTest(t, logger),
			},
			expect: []byte("{\"Broadcasts\":{\"" + testMAC + "\":{\"MAC\":\"" + testMAC + "\",\"URLs\":[\"" + testURL + "\"],\"Status\":\"" + statusSlate + "\"}},\"SlateExitSignals\":[\"" + testMAC + "\"]}"),
		},
	}

	for i, test := range tests {
		got, err := test.in.MarshalJSON()
		if err != nil {
			t.Errorf("could not marshal json for test no. %d: %v", i, err)
			continue
		}
		if !bytes.Equal(got, test.expect) {
			t.Errorf("did not get expected result.\nGot: %v\nWnt: %v\n", string(got), string(test.expect))
		}
	}
}

func TestBroadcastManagerUnmarshal(t *testing.T) {
	logger := (*logging.TestLogger)(t)

	// Marshalling functionality uses this.
	global.SetLogger(logger)

	tests := []struct {
		in     []byte
		expect broadcastManager
	}{
		{
			in: []byte("{\"Broadcasts\":{\"" + testMAC + "\":{\"MAC\":\"" + testMAC + "\",\"URLs\":[\"" + testURL + "\"],\"Status\":\"" + statusSlate + "\"}},\"SlateExitSignals\":[\"" + testMAC + "\"]}"),
			expect: broadcastManager{
				broadcasts: map[MAC]*Broadcast{
					testMAC: &Broadcast{
						testMAC,
						[]string{testURL},
						statusSlate,
						newRevidForTest((*logging.TestLogger)(t), testURL, t),
					},
				},
				slateExitSignals: newExitSignalsForTest(t, testMAC),
				log:              logger,
				dogNotifier:      newWatchdogNotifierForTest(t, logger),
			},
		},
	}

	for i, test := range tests {
		var got broadcastManager
		if err := json.Unmarshal(test.in, &got); err != nil {
			t.Errorf("could not unmarshal json for test no. %d: %v", i, err)
			continue
		}
		if !broadcastManagersEqual(got, test.expect) {
			t.Errorf("did not get expected result.\nGot: %+v\nWnt: %+v\n", got, test.expect)
		}
	}
}

func broadcastManagersEqual(m1, m2 broadcastManager) bool {
	if !broadcastMapsEqual(m1.broadcasts, m2.broadcasts) ||
		!slateExitSignalMapsEqual(m1.slateExitSignals, m2.slateExitSignals) ||
		!watchdogNotifiersEqual(*m1.dogNotifier, *m2.dogNotifier) {
		return false
	}
	return true
}

func broadcastMapsEqual(m1, m2 map[MAC]*Broadcast) bool {
	return mapsEqual(m1, m2, broadcastsEqual)
}

func slateExitSignalMapsEqual(m1, m2 map[MAC]chan struct{}) bool {
	return mapsEqual(m1, m2, func(v1, v2 chan struct{}) bool {
		return ((v1 == nil || v2 == nil) && v1 == v2) || (v1 != nil && v2 != nil)
	})
}

func activeHandlersMapEqual(m1, m2 map[int]handlerInfo) bool {
	return mapsEqual(m1, m2, func(v1, v2 handlerInfo) bool { return v1.name == v2.name })
}

// mapsEqual is a generic function to check that any two maps are equal based on
// the provided value compare function cmp.
func mapsEqual[K comparable, V any](m1, m2 map[K]V, cmp func(v1, v2 V) bool) bool {
	if len(m1) != len(m2) {
		return false
	}
	for k, v1 := range m1 {
		v2, ok := m2[k]
		if !ok || !cmp(v1, v2) {
			return false
		}
	}
	return true
}

func watchdogNotifiersEqual(w1, w2 watchdogNotifier) bool {
	if w1.watchdogInterval != w2.watchdogInterval ||
		!activeHandlersMapEqual(w1.activeHandlers, w2.activeHandlers) {
		return false
	}
	return true
}

func broadcastsEqual(b1, b2 *Broadcast) bool {
	if b1 == nil {
		panic("b1 is nil")
	}
	if b2 == nil {
		panic("b2 is nil")
	}
	if b1.mac != b2.mac || !reflect.DeepEqual(b1.urls, b2.urls) || b1.status != b2.status ||
		((b1.rv == nil || b2.rv == nil) && b1.rv != b2.rv) {
		return false
	}
	if b1.rv != nil && !configsEqual(b1.rv.Config(), b2.rv.Config()) {
		return false
	}
	return true
}

// configsEqual returns true if the provided config.Config values are equal. The
// comparison is shallow given that only fields of basic types are compared, not
// structs or interfaces.
func configsEqual(cfg1, cfg2 config.Config) bool {
	cfg1ValOf := reflect.ValueOf(cfg1)
	cfg2ValOf := reflect.ValueOf(cfg2)
	for i := 0; i < cfg1ValOf.NumField(); i++ {
		if cfg1ValOf.Field(i).Kind() == reflect.Struct || cfg1ValOf.Field(i).Kind() == reflect.Interface {
			continue
		}
		if !reflect.DeepEqual(cfg1ValOf.Field(i).Interface(), cfg2ValOf.Field(i).Interface()) {
			return false
		}
	}
	return true
}

// newRevidForTest allows us to create revid in table driven test entry.
func newRevidForTest(log logging.Logger, url string, t *testing.T) *revid.Revid {
	r, err := newRevid(log, []string{url})
	if err != nil {
		t.Fatalf("could not create revid pipeline: %v", err)
		return nil
	}
	return r
}

// newExitSignalsForTest creates a map of chan struct{} for the provided MACs.
// This is used to populate the slateExitSignals field in the broadcastManager.
func newExitSignalsForTest(t *testing.T, macs ...MAC) map[MAC]chan struct{} {
	sigMap := make(map[MAC]chan struct{})
	for _, m := range macs {
		sigMap[m] = make(chan struct{})
	}
	return sigMap
}

// newWatchdogNotifierForTest allows us to create watchdog notifier in test table.
func newWatchdogNotifierForTest(t *testing.T, l logging.Logger) *watchdogNotifier {
	n, err := newWatchdogNotifier(l, func() {})
	if err != nil {
		t.Fatalf("could not create new watchdog notifier: %v", err)
		return nil
	}
	return n
}