package mqtt

import (
	"context"
	"log/slog"
	"testing"
	"time"

	"gitea.lab.audasmedia.com.au/sam/internet_use_control/internal/store"
)

// fakes for the link's collaborators.

type fakeDevices struct{ dev store.Device }

func (f fakeDevices) DeviceByConfigTopic(context.Context, string) (*store.Device, error) {
	d := f.dev
	return &d, nil
}

type fakeReports struct{ presence bool }

func (f *fakeReports) SetPresence(_ context.Context, _ int64, online bool, _ time.Time, _ string) (bool, error) {
	f.presence = online
	return true, nil
}

func (f *fakeReports) InsertTelemetry(context.Context, int64, string, []store.TelemetryEntry) (int, error) {
	return 0, nil
}

type fakeSource struct{}

func (fakeSource) ListDevices(context.Context) ([]store.Device, error) { return nil, nil }

func (fakeSource) EffectiveState(context.Context, store.Device, time.Time) (store.EffectiveState, error) {
	return store.EffectiveState{}, nil
}

// fakeMessage satisfies paho.Message for a received report.
type fakeMessage struct {
	topic   string
	payload []byte
}

func (m fakeMessage) Duplicate() bool   { return false }
func (m fakeMessage) Qos() byte         { return 1 }
func (m fakeMessage) Retained() bool    { return true }
func (m fakeMessage) Topic() string     { return m.topic }
func (m fakeMessage) MessageID() uint16 { return 0 }
func (m fakeMessage) Payload() []byte   { return m.payload }
func (m fakeMessage) Ack()              {}

func newTestLink(t *testing.T, dev store.Device, reports *fakeReports, onTamper func(context.Context, store.Device, Tamper)) *Link {
	t.Helper()
	l, err := New(Options{
		Broker:  "tcp://broker.invalid:1883",
		Log:     slog.New(slog.DiscardHandler),
		Devices: fakeDevices{dev: dev},
		Source:  fakeSource{},
		Reports: reports,
		OnTamper: onTamper,
	})
	if err != nil {
		t.Fatalf("New: %v", err)
	}
	// The paho client itself is never used by handleStatusMessage.
	l.client = nil
	return l
}

func TestStatusTamperReachesTheSink(t *testing.T) {
	dev := store.Device{ID: 1, Name: "Harry's phone", Topic: "restrict/harry_phone_1/config"}
	reports := &fakeReports{}

	var got Tamper
	var calls int
	l := newTestLink(t, dev, reports, func(_ context.Context, d store.Device, tamper Tamper) {
		calls++
		got = tamper
		if d.ID != dev.ID {
			t.Errorf("device id = %d, want %d", d.ID, dev.ID)
		}
	})

	payload := `{"online":true,"tamper":{"kind":"accessibility_disabled","detail":"the service was destroyed"}}`
	l.handleStatusMessage(nil, fakeMessage{topic: "restrict/harry_phone_1/status", payload: []byte(payload)})

	if calls != 1 {
		t.Fatalf("OnTamper calls = %d, want 1", calls)
	}
	if got.Kind != "accessibility_disabled" {
		t.Errorf("kind = %q", got.Kind)
	}
	if !reports.presence {
		t.Error("presence was not recorded alongside the tamper")
	}
}

func TestPlainStatusDoesNotTamper(t *testing.T) {
	dev := store.Device{ID: 2, Name: "Finn's phone", Topic: "restrict/finn_phone_2/config"}
	reports := &fakeReports{}
	l := newTestLink(t, dev, reports, func(context.Context, store.Device, Tamper) {
		t.Error("OnTamper called for a plain status")
	})
	l.handleStatusMessage(nil, fakeMessage{topic: "restrict/finn_phone_2/status", payload: []byte(`{"online":true}`)})
	if !reports.presence {
		t.Error("presence was not recorded")
	}
}