package mqtt

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

	"github.com/eclipse/paho.golang/paho"
	"robot-market/test-mqtt-5/internal/config"
	"robot-market/test-mqtt-5/internal/events"
)

func TestCopyAndOverflow(t *testing.T) {
	cfg := config.Defaults()
	cfg.Limits.InboundQueue = 1
	c := New(cfg, events.NewStore(4, slog.New(slog.NewTextHandler(io.Discard, nil))))
	p := &paho.Publish{Topic: Topic(cfg, "acks"), Payload: []byte("payload"), Properties: &paho.PublishProperties{CorrelationData: []byte("id"), MessageExpiry: paho.Uint32(5)}}
	c.receive(paho.PublishReceived{Packet: p})
	p.Payload[0] = 'X'
	p.Properties.CorrelationData[0] = 'X'
	*p.Properties.MessageExpiry = 99
	c.receive(paho.PublishReceived{Packet: p})
	if c.dropped.Load() != 1 {
		t.Fatal("overflow not counted")
	}
	got := <-c.Incoming
	if string(got.Payload) != "payload" || string(got.Properties.CorrelationData) != "id" || *got.Properties.MessageExpiry != 5 {
		t.Fatal("callback input was aliased")
	}
	p.Topic = "production/topic"
	c.receive(paho.PublishReceived{Packet: p})
	if c.invalid.Load() != 1 {
		t.Fatal("foreign topic not rejected")
	}
}
func TestBoundedBackoff(t *testing.T) {
	f := Backoff(time.Second, 30*time.Second)
	for attempt := 0; attempt < 100; attempt++ {
		for n := 0; n < 10; n++ {
			d := f(attempt)
			if d < time.Second || d > 30*time.Second {
				t.Fatal("backoff outside bounds")
			}
		}
	}
}
func TestTLSNeverSkipsVerification(t *testing.T) {
	cfg := config.Defaults()
	tc, err := TLSConfig(cfg)
	if err != nil || tc.InsecureSkipVerify || tc.MinVersion == 0 {
		t.Fatal("unsafe TLS")
	}
}

func TestObservedDeviceTopicIdentity(t *testing.T) {
	cfg := config.Defaults()
	cfg.Topics.ObserveDevices = "sim-001, esp32-lab-001,esp32-lab-001"
	if len(ObservedDevices(cfg)) != 2 {
		t.Fatal("duplicate subscriptions")
	}
	device, kind := Identity(cfg, "robot-market/test/v1/esp32-lab-001/telemetry")
	if device != "esp32-lab-001" || kind != "telemetry" {
		t.Fatal("device topic missing")
	}
	for _, topic := range []string{"robot-market/test/v1/other/telemetry", "production/esp32-lab-001/telemetry", "robot-market/test/v1/esp32-lab-001/unknown"} {
		if _, kind := Identity(cfg, topic); kind != "" {
			t.Fatal("unconfigured topic admitted")
		}
	}
}

func TestRawObservationAdmitsNamespaceWithoutDeviceOrCategoryRestriction(t *testing.T) {
	cfg := config.Defaults()
	cfg.Topics.ObserveAll = true
	c := New(cfg, events.NewStore(8, slog.New(slog.NewTextHandler(io.Discard, nil))))
	for _, topic := range []string{cfg.Topics.Namespace, cfg.Topics.Namespace + "/custom", cfg.Topics.Namespace + "/new-device/custom-topic"} {
		c.receive(paho.PublishReceived{Packet: &paho.Publish{Topic: topic, Payload: []byte("not JSON")}})
		select {
		case got := <-c.Incoming:
			if got.Topic != topic {
				t.Fatal("topic changed")
			}
		default:
			t.Fatal("raw topic filtered")
		}
	}
	c.receive(paho.PublishReceived{Packet: &paho.Publish{Topic: cfg.Topics.Namespace + "-other/device/custom"}})
	if c.invalid.Load() != 1 {
		t.Fatal("namespace boundary lost")
	}
}