Add GeoClue2 integration as alternative to IP location (#1856)

* feat: switch auto location in weather widget to use GeoClue2 instead of simple IP check

* nix: enable GeoClue2 service by default

* lint: fix line endings

* fix: fall back to IP location if GeoClue is not available

core/internal/server/location/handlers.go

@@ -0,0 +1,61 @@
+package location
+
+import (
+	"encoding/json"
+	"fmt"
+	"net"
+
+	"github.com/AvengeMedia/DankMaterialShell/core/internal/server/models"
+)
+
+type LocationEvent struct {
+	Type string `json:"type"`
+	Data State  `json:"data"`
+}
+
+func HandleRequest(conn net.Conn, req models.Request, manager *Manager) {
+	switch req.Method {
+	case "location.getState":
+		handleGetState(conn, req, manager)
+	case "location.subscribe":
+		handleSubscribe(conn, req, manager)
+
+	default:
+		models.RespondError(conn, req.ID, fmt.Sprintf("unknown method: %s", req.Method))
+	}
+}
+
+func handleGetState(conn net.Conn, req models.Request, manager *Manager) {
+	models.Respond(conn, req.ID, manager.GetState())
+}
+
+func handleSubscribe(conn net.Conn, req models.Request, manager *Manager) {
+	clientID := fmt.Sprintf("client-%p", conn)
+	stateChan := manager.Subscribe(clientID)
+	defer manager.Unsubscribe(clientID)
+
+	initialState := manager.GetState()
+	event := LocationEvent{
+		Type: "state_changed",
+		Data: initialState,
+	}
+
+	if err := json.NewEncoder(conn).Encode(models.Response[LocationEvent]{
+		ID:     req.ID,
+		Result: &event,
+	}); err != nil {
+		return
+	}
+
+	for state := range stateChan {
+		event := LocationEvent{
+			Type: "state_changed",
+			Data: state,
+		}
+		if err := json.NewEncoder(conn).Encode(models.Response[LocationEvent]{
+			Result: &event,
+		}); err != nil {
+			return
+		}
+	}
+}

core/internal/server/location/manager.go

@@ -0,0 +1,174 @@
+package location
+
+import (
+	"time"
+
+	"github.com/AvengeMedia/DankMaterialShell/core/internal/geolocation"
+	"github.com/AvengeMedia/DankMaterialShell/core/internal/log"
+)
+
+func NewManager(client geolocation.Client) (*Manager, error) {
+	currLocation, err := client.GetLocation()
+	if err != nil {
+		log.Warnf("Failed to get initial location: %v", err)
+	}
+
+	m := &Manager{
+		client: client,
+		dirty:  make(chan struct{}),
+
+		state: &State{
+			Latitude:  currLocation.Latitude,
+			Longitude: currLocation.Longitude,
+		},
+	}
+
+	if err := m.startSignalPump(); err != nil {
+		return nil, err
+	}
+
+	m.notifierWg.Add(1)
+	go m.notifier()
+
+	return m, nil
+}
+
+func (m *Manager) Close() {
+	close(m.stopChan)
+	m.notifierWg.Wait()
+
+	m.sigWG.Wait()
+
+	m.subscribers.Range(func(key string, ch chan State) bool {
+		close(ch)
+		m.subscribers.Delete(key)
+		return true
+	})
+}
+
+func (m *Manager) Subscribe(id string) chan State {
+	ch := make(chan State, 64)
+	m.subscribers.Store(id, ch)
+	return ch
+}
+
+func (m *Manager) Unsubscribe(id string) {
+	if ch, ok := m.subscribers.LoadAndDelete(id); ok {
+		close(ch)
+	}
+}
+
+func (m *Manager) startSignalPump() error {
+	m.sigWG.Add(1)
+	go func() {
+		defer m.sigWG.Done()
+
+		subscription := m.client.Subscribe("locationManager")
+		defer m.client.Unsubscribe("locationManager")
+
+		for {
+			select {
+			case <-m.stopChan:
+				return
+			case location, ok := <-subscription:
+				if !ok {
+					return
+				}
+
+				m.handleLocationChange(location)
+			}
+		}
+	}()
+
+	return nil
+}
+
+func (m *Manager) handleLocationChange(location geolocation.Location) {
+	m.stateMutex.Lock()
+	defer m.stateMutex.Unlock()
+
+	m.state.Latitude = location.Latitude
+	m.state.Longitude = location.Longitude
+
+	m.notifySubscribers()
+}
+
+func (m *Manager) notifySubscribers() {
+	select {
+	case m.dirty <- struct{}{}:
+	default:
+	}
+}
+
+func (m *Manager) GetState() State {
+	m.stateMutex.RLock()
+	defer m.stateMutex.RUnlock()
+	if m.state == nil {
+		return State{
+			Latitude:  0.0,
+			Longitude: 0.0,
+		}
+	}
+	stateCopy := *m.state
+	return stateCopy
+}
+
+func (m *Manager) notifier() {
+	defer m.notifierWg.Done()
+	const minGap = 200 * time.Millisecond
+	timer := time.NewTimer(minGap)
+	timer.Stop()
+	var pending bool
+
+	for {
+		select {
+		case <-m.stopChan:
+			timer.Stop()
+			return
+		case <-m.dirty:
+			if pending {
+				continue
+			}
+			pending = true
+			timer.Reset(minGap)
+		case <-timer.C:
+			if !pending {
+				continue
+			}
+
+			currentState := m.GetState()
+
+			if m.lastNotified != nil && !stateChanged(m.lastNotified, &currentState) {
+				pending = false
+				continue
+			}
+
+			m.subscribers.Range(func(key string, ch chan State) bool {
+				select {
+				case ch <- currentState:
+				default:
+					log.Warn("Location: subscriber channel full, dropping update")
+				}
+				return true
+			})
+
+			stateCopy := currentState
+			m.lastNotified = &stateCopy
+			pending = false
+		}
+	}
+}
+
+func stateChanged(old, new *State) bool {
+	if old == nil || new == nil {
+		return true
+	}
+	if old.Latitude != new.Latitude {
+		return true
+	}
+	if old.Longitude != new.Longitude {
+		return true
+	}
+
+	return false
+}

core/internal/server/location/types.go

@@ -0,0 +1,28 @@
+package location
+
+import (
+	"sync"
+
+	"github.com/AvengeMedia/DankMaterialShell/core/internal/geolocation"
+	"github.com/AvengeMedia/DankMaterialShell/core/pkg/syncmap"
+)
+
+type State struct {
+	Latitude  float64 `json:"latitude"`
+	Longitude float64 `json:"longitude"`
+}
+
+type Manager struct {
+	state      *State
+	stateMutex sync.RWMutex
+
+	client geolocation.Client
+
+	stopChan chan struct{}
+	sigWG    sync.WaitGroup
+
+	subscribers  syncmap.Map[string, chan State]
+	dirty        chan struct{}
+	notifierWg   sync.WaitGroup
+	lastNotified *State
+}