package notify

import (
	"context"
	"errors"
	"testing"
)

func TestClientStopSessionIfCurrentEpoch(t *testing.T) {
	client := NewClient().(*ClientCommon)
	client.markSessionStarted()

	staleEpoch := client.beginClientSessionEpoch()
	currentEpoch := client.beginClientSessionEpoch()

	if client.stopClientSessionIfCurrent(staleEpoch, "stale", nil) {
		t.Fatal("stale epoch should not stop current session")
	}
	status := client.Status()
	if !status.Alive || status.Reason != "" || status.Err != nil {
		t.Fatalf("unexpected status after stale stop: %+v", status)
	}

	if !client.stopClientSessionIfCurrent(currentEpoch, "current", nil) {
		t.Fatal("current epoch should stop session")
	}
	status = client.Status()
	if status.Alive || status.Reason != "current" || status.Err != nil {
		t.Fatalf("unexpected status after current stop: %+v", status)
	}
}

func TestClientReadErrorWithStaleEpochDoesNotStopCurrentSession(t *testing.T) {
	client := NewClient().(*ClientCommon)
	client.markSessionStarted()

	staleEpoch := client.beginClientSessionEpoch()
	currentEpoch := client.beginClientSessionEpoch()

	readErr := errors.New("read failed")
	client.handleTransportReadResultWithSession(context.Background(), nil, nil, 0, nil, readErr, staleEpoch)

	status := client.Status()
	if !status.Alive || status.Reason != "" || status.Err != nil {
		t.Fatalf("unexpected status after stale read error: %+v", status)
	}

	client.handleTransportReadResultWithSession(context.Background(), nil, nil, 0, nil, readErr, currentEpoch)

	status = client.Status()
	if status.Alive || status.Reason != "client read error" || !errors.Is(status.Err, readErr) {
		t.Fatalf("unexpected status after current read error: %+v", status)
	}
}

func TestHeartbeatFailureWithStaleEpochDoesNotStopCurrentSession(t *testing.T) {
	client := NewClient().(*ClientCommon)
	client.markSessionStarted()

	staleEpoch := client.beginClientSessionEpoch()
	currentEpoch := client.beginClientSessionEpoch()
	heartbeatErr := errors.New("heartbeat failed")

	failedCount, stop := client.handleHeartbeatResultWithSession(staleEpoch, heartbeatErr, 2)
	if failedCount != 3 || !stop {
		t.Fatalf("unexpected stale heartbeat result: failedCount=%d stop=%v", failedCount, stop)
	}
	status := client.Status()
	if !status.Alive || status.Reason != "" || status.Err != nil {
		t.Fatalf("unexpected status after stale heartbeat error: %+v", status)
	}

	failedCount, stop = client.handleHeartbeatResultWithSession(currentEpoch, heartbeatErr, 2)
	if failedCount != 3 || !stop {
		t.Fatalf("unexpected current heartbeat result: failedCount=%d stop=%v", failedCount, stop)
	}
	status = client.Status()
	if status.Alive || status.Reason != "heartbeat failed more than 3 times" || status.Err == nil || status.Err.Error() != "heartbeat failed more than 3 times" {
		t.Fatalf("unexpected status after current heartbeat error: %+v", status)
	}
}