another.im-ios/Monal/another.im/Views/Conversation/Attachments/LocationPickerView.swift

import MapKit
import SwiftUI

struct LocationPickerView: View {
    @Environment(\.router) var router
    // @EnvironmentObject var messages: MessagesStore

    @StateObject var locationManager = LocationManager()
    @State private var region = MKCoordinateRegion()

    var body: some View {
        VStack(spacing: 0) {
            ZStack {
                // MapView
                MapView(region: $region)
                    .onAppear {
                        DispatchQueue.main.asyncAfter(deadline: .now() + 0.5) {
                            self.region = locationManager.region
                        }
                    }
                    .overlay {
                        Image(systemName: "mappin")
                            .foregroundColor(.Material.Elements.active)
                            .font(.system(size: 30))
                            .shadow(color: .white, radius: 2)
                    }

                // Track button
                VStack {
                    Spacer()
                    HStack {
                        Spacer()
                        Image(systemName: "location.circle")
                            .resizable()
                            .frame(width: 40, height: 40)
                            .foregroundColor(.Material.Elements.active)
                            .background(Color.Material.Shape.white)
                            .clipShape(Circle())
                            .shadow(color: .white, radius: 2)
                            .padding(.trailing)
                            .padding(.bottom, 50)
                            .tappablePadding(.symmetric(10)) {
                                self.region = locationManager.region
                            }
                    }
                }
            }

            // Send panel
            Rectangle()
                .foregroundColor(.Material.Shape.black)
                .frame(maxWidth: .infinity)
                .frame(height: 50)
                .overlay {
                    HStack {
                        Text(L10n.Attachment.Send.location)
                            .foregroundColor(.Material.Text.white)
                            .font(.body1)
                        Image(systemName: "arrow.up.circle")
                            .foregroundColor(.Material.Text.white)
                            .font(.body1)
                            .padding(.leading, 8)
                    }
                    .padding()
                }
                .clipped()
                .onTapGesture {
                    // messages.sendLocation(region.center.latitude, region.center.longitude)
                    router.dismissEnvironment()
                }
        }
        .onAppear {
            locationManager.start()
        }
    }
}

struct MapView: UIViewRepresentable {
    @Binding var region: MKCoordinateRegion

    func makeUIView(context: Context) -> MKMapView {
        let mapView = MKMapView()
        mapView.delegate = context.coordinator
        mapView.showsUserLocation = false
        mapView.userTrackingMode = .none

        return mapView
    }

    func updateUIView(_ uiView: MKMapView, context _: Context) {
        if uiView.region != region {
            uiView.setRegion(region, animated: true)
        }
    }

    func makeCoordinator() -> Coordinator {
        Coordinator(self)
    }

    class Coordinator: NSObject, MKMapViewDelegate {
        var parent: MapView

        init(_ parent: MapView) {
            self.parent = parent
        }
    }
}

class LocationManager: NSObject, ObservableObject, CLLocationManagerDelegate {
    private let locationManager = CLLocationManager()
    @Published var region: MKCoordinateRegion

    override init() {
        region = MKCoordinateRegion()
        super.init()
        locationManager.delegate = self
        locationManager.desiredAccuracy = kCLLocationAccuracyBest
    }

    func start() {
        locationManager.requestWhenInUseAuthorization()
        locationManager.startUpdatingLocation()
    }

    func stop() {
        locationManager.stopUpdatingLocation()
    }

    func locationManager(_: CLLocationManager, didUpdateLocations locations: [CLLocation]) {
        if let loc = locations.first {
            region = MKCoordinateRegion(
                center: loc.coordinate,
                span: MKCoordinateSpan(latitudeDelta: 0.002, longitudeDelta: 0.002)
            )
        }
    }
}