package bridge

import (
	"context"
	"encoding/json"
	"testing"
	"time"

	"github.com/AFASystems/presence/internal/pkg/common/appcontext"
	"github.com/AFASystems/presence/internal/pkg/model"
	mqtt "github.com/eclipse/paho.mqtt.golang"
)

// MockMQTTClient is a mock implementation of mqtt.Client for testing
type MockMQTTClient struct {
	PublishedMessages map[string][]byte
}

func NewMockMQTTClient() *MockMQTTClient {
	return &MockMQTTClient{
		PublishedMessages: make(map[string][]byte),
	}
}

func (m *MockMQTTClient) Publish(topic string, qos byte, retained bool, payload interface{}) mqtt.Token {
	// Convert payload to bytes
	var payloadBytes []byte
	if b, ok := payload.([]byte); ok {
		payloadBytes = b
	} else {
		payloadBytes, _ = json.Marshal(payload)
	}
	m.PublishedMessages[topic] = payloadBytes
	return &mockToken{}
}

func (m *MockMQTTClient) Subscribe(topic string, qos byte, handler mqtt.MessageHandler) mqtt.Token {
	return &mockToken{}
}

func (m *MockMQTTClient) Disconnect(quiesce uint) {
	// Mock implementation
}

type mockToken struct{}

func (m *mockToken) Wait() bool {
	return true
}

func (m *mockToken) WaitTimeout(time.Duration) bool {
	return true
}

func (m *mockToken) Error() error {
	return nil
}

func (m *mockToken) Done() <-chan struct{} {
	ch := make(chan struct{})
	close(ch)
	return ch
}

func TestEventLoop_ApiUpdate_POST(t *testing.T) {
	// Setup
	appState := appcontext.NewAppState()

	chApi := make(chan model.ApiUpdate, 10)
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	// Create a POST message
	msg := model.ApiUpdate{
		Method: "POST",
		MAC:    "AA:BB:CC:DD:EE:FF",
		ID:     "beacon-123",
	}

	// Test channel send in a goroutine
	go func() {
		chApi <- msg
		time.Sleep(100 * time.Millisecond)
		cancel()
	}()

	// Simulate the event loop handling
	select {
	case <-ctx.Done():
		// Context canceled
	case msg := <-chApi:
		if msg.Method == "POST" {
			appState.AddBeaconToLookup(msg.MAC, msg.ID)
		}
	}

	// Assert
	beaconID, exists := appState.BeaconExists("AA:BB:CC:DD:EE:FF")
	if !exists {
		t.Error("Expected beacon to exist in lookup")
	}

	if beaconID != "beacon-123" {
		t.Errorf("Expected beacon ID 'beacon-123', got '%s'", beaconID)
	}
}

func TestEventLoop_ApiUpdate_DELETE(t *testing.T) {
	// Setup
	appState := appcontext.NewAppState()
	appState.AddBeaconToLookup("AA:BB:CC:DD:EE:FF", "beacon-123")

	chApi := make(chan model.ApiUpdate, 10)

	// Create a DELETE message
	msg := model.ApiUpdate{
		Method: "DELETE",
		MAC:    "AA:BB:CC:DD:EE:FF",
	}

	// Simulate the event loop handling
	chApi <- msg

	select {
	case msg := <-chApi:
		if msg.Method == "DELETE" {
			appState.RemoveBeaconFromLookup(msg.MAC)
		}
	case <-time.After(1 * time.Second):
		t.Fatal("Timeout waiting for message")
	}

	// Assert
	_, exists := appState.BeaconExists("AA:BB:CC:DD:EE:FF")
	if exists {
		t.Error("Expected beacon to be removed from lookup")
	}
}

func TestEventLoop_ApiUpdate_DELETE_All(t *testing.T) {
	// Setup
	appState := appcontext.NewAppState()
	appState.AddBeaconToLookup("AA:BB:CC:DD:EE:FF", "beacon-1")
	appState.AddBeaconToLookup("11:22:33:44:55:66", "beacon-2")

	chApi := make(chan model.ApiUpdate, 10)

	// Create a DELETE all message
	msg := model.ApiUpdate{
		Method: "DELETE",
		MAC:    "all",
	}

	// Simulate the event loop handling
	chApi <- msg

	select {
	case msg := <-chApi:
		if msg.Method == "DELETE" && msg.MAC == "all" {
			appState.CleanLookup()
		}
	case <-time.After(1 * time.Second):
		t.Fatal("Timeout waiting for message")
	}

	// Assert
	_, exists1 := appState.BeaconExists("AA:BB:CC:DD:EE:FF")
	_, exists2 := appState.BeaconExists("11:22:33:44:55:66")

	if exists1 || exists2 {
		t.Error("Expected all beacons to be removed from lookup")
	}
}

func TestEventLoop_AlertMessage(t *testing.T) {
	// Setup
	mockClient := NewMockMQTTClient()

	chAlert := make(chan model.Alert, 10)

	// Create an alert message
	msg := model.Alert{
		ID:    "tracker-123",
		Type:  "battery_low",
		Value: "15",
	}

	go func() {
		alert := <-chAlert
		p, _ := json.Marshal(alert)
		mockClient.Publish("/alerts", 0, true, p)
	}()

	chAlert <- msg
	time.Sleep(100 * time.Millisecond)

	// Assert
	if _, exists := mockClient.PublishedMessages["/alerts"]; !exists {
		t.Error("Expected message to be published to /alerts topic")
	}

	var publishedAlert model.Alert
	err := json.Unmarshal(mockClient.PublishedMessages["/alerts"], &publishedAlert)
	if err != nil {
		t.Fatalf("Failed to unmarshal published alert: %v", err)
	}

	if publishedAlert.ID != "tracker-123" {
		t.Errorf("Expected ID 'tracker-123', got '%s'", publishedAlert.ID)
	}

	if publishedAlert.Type != "battery_low" {
		t.Errorf("Expected Type 'battery_low', got '%s'", publishedAlert.Type)
	}
}

func TestEventLoop_TrackerMessage(t *testing.T) {
	// Setup
	mockClient := NewMockMQTTClient()

	chMqtt := make(chan []model.Tracker, 10)

	// Create tracker messages
	trackers := []model.Tracker{
		{
			ID:     "tracker-1",
			Name:   "Tracker One",
			MAC:    "AA:BB:CC:DD:EE:FF",
			Status: "active",
			X:      10.5,
			Y:      20.3,
		},
		{
			ID:     "tracker-2",
			Name:   "Tracker Two",
			MAC:    "11:22:33:44:55:66",
			Status: "inactive",
			X:      15.2,
			Y:      25.7,
		},
	}

	go func() {
		trackerMsg := <-chMqtt
		p, _ := json.Marshal(trackerMsg)
		mockClient.Publish("/trackers", 0, true, p)
	}()

	chMqtt <- trackers
	time.Sleep(100 * time.Millisecond)

	// Assert
	if _, exists := mockClient.PublishedMessages["/trackers"]; !exists {
		t.Error("Expected message to be published to /trackers topic")
	}

	var publishedTrackers []model.Tracker
	err := json.Unmarshal(mockClient.PublishedMessages["/trackers"], &publishedTrackers)
	if err != nil {
		t.Fatalf("Failed to unmarshal published trackers: %v", err)
	}

	if len(publishedTrackers) != 2 {
		t.Errorf("Expected 2 trackers, got %d", len(publishedTrackers))
	}

	if publishedTrackers[0].Name != "Tracker One" {
		t.Errorf("Expected tracker name 'Tracker One', got '%s'", publishedTrackers[0].Name)
	}
}

func TestEventLoop_ContextCancellation(t *testing.T) {
	// Setup
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	chApi := make(chan model.ApiUpdate, 10)
	chAlert := make(chan model.Alert, 10)
	chMqtt := make(chan []model.Tracker, 10)

	// Cancel context immediately
	cancel()

	// Simulate event loop
	select {
	case <-ctx.Done():
		// Expected - context was canceled
		return
	case msg := <-chApi:
		t.Errorf("Should not receive API messages after context cancellation, got: %+v", msg)
	case msg := <-chAlert:
		t.Errorf("Should not receive alert messages after context cancellation, got: %+v", msg)
	case msg := <-chMqtt:
		t.Errorf("Should not receive tracker messages after context cancellation, got: %+v", msg)
	case <-time.After(1 * time.Second):
		t.Error("Timeout - context cancellation should have been immediate")
	}
}