ContentView.swift

import SwiftUI
import MapKit
struct TappableMapView: UIViewRepresentable {
    let onTap: ((CLLocationCoordinate2D) -> Void)?
    @Binding var annotations: [MKPointAnnotation]
    @Binding var region: MKCoordinateRegion
    @Binding var shouldCenter: Bool

    func makeUIView(context: Context) -> MKMapView {
        let mapView = MKMapView(frame: .zero)
        mapView.delegate = context.coordinator
        let tapGesture = UITapGestureRecognizer(target: context.coordinator,
                                                action: #selector(Coordinator.handleTap(_:)))
        mapView.addGestureRecognizer(tapGesture)
        mapView.setRegion(region, animated: false)
        return mapView
    }
    
    func updateUIView(_ uiView: MKMapView, context: Context) {
        if shouldCenter {
            uiView.setRegion(region, animated: true)
            DispatchQueue.main.async {
                self.shouldCenter = false
            }
        }
        uiView.removeAnnotations(uiView.annotations)
        uiView.addAnnotations(annotations)
    }
    
    func makeCoordinator() -> Coordinator {
        Coordinator(self)
    }
    class Coordinator: NSObject, MKMapViewDelegate {
        var parent: TappableMapView
        
        init(_ parent: TappableMapView) {
            self.parent = parent
        }
        
        @objc func handleTap(_ gestureRecognizer: UITapGestureRecognizer) {
            guard let mapView = gestureRecognizer.view as? MKMapView else { return }
            let tapPoint = gestureRecognizer.location(in: mapView)
            let coordinate = mapView.convert(tapPoint, toCoordinateFrom: mapView)
            parent.onTap?(coordinate)
        }
        func mapView(_ mapView: MKMapView, regionDidChangeAnimated animated: Bool) {
            parent.region = mapView.region
        }
    }
}
struct ContentView: View {
    @State private var annotations: [MKPointAnnotation] = {
        let memorialAnnotation = MKPointAnnotation()
        memorialAnnotation.coordinate = CLLocationCoordinate2D(latitude: 38.54237287621318,
                                                               longitude: -121.74955185519764)
        memorialAnnotation.title = "Memorial Union"
        return [memorialAnnotation]
    }()
    @State private var region = MKCoordinateRegion(
        center: CLLocationCoordinate2D(latitude: 38.54237287621318,
                                       longitude: -121.74955185519764),
        latitudinalMeters: 5000,
        longitudinalMeters: 5000
    )
    @State private var shouldCenter: Bool = false
    @State private var tappedCoordinate: CLLocationCoordinate2D? = nil
    @State private var newMarkerName: String = ""
    @State private var showMarkerEditor: Bool = false
    
    var body: some View {
        ZStack {
            TappableMapView(onTap: { coordinate in
                tappedCoordinate = coordinate
                newMarkerName = ""
                showMarkerEditor = true
            },
            annotations: $annotations,
            region: $region,
            shouldCenter: $shouldCenter)
                .edgesIgnoringSafeArea(.all)
            VStack {
                Spacer()
                HStack {
                    Spacer()
                    Button {
                        region = MKCoordinateRegion(
                            center: CLLocationCoordinate2D(latitude: 38.54237287621318,
                                                           longitude: -121.74955185519764),
                            latitudinalMeters: 200,
                            longitudinalMeters: 200
                        )
                        shouldCenter = true
                    } label: {
                        Text("MU")
                            .padding()
                    }
                    Spacer()
                }
                .background(.thinMaterial)
            }
            if showMarkerEditor {
                Color.black.opacity(0.4)
                    .edgesIgnoringSafeArea(.all)
                VStack(spacing: 20) {
                    Text("Enter a name for the location:")
                        .font(.headline)
                    
                    TextField("Location name", text: $newMarkerName)
                        .textFieldStyle(RoundedBorderTextFieldStyle())
                        .padding(.horizontal)
                    
                    HStack {
                        Button(action: {
                            showMarkerEditor = false
                        }, label: {
                            Text("Cancel")
                                .frame(maxWidth: .infinity)
                                .padding()
                                .background(Color.gray.opacity(0.2))
                                .cornerRadius(8)
                        })
                        
                        Button(action: {
                            if let coordinate = tappedCoordinate,
                               !newMarkerName.trimmingCharacters(in: .whitespaces).isEmpty {
                                let newAnnotation = MKPointAnnotation()
                                newAnnotation.coordinate = coordinate
                                newAnnotation.title = newMarkerName
                                annotations.append(newAnnotation)
                            }
                            showMarkerEditor = false
                        }, label: {
                            Text("Add")
                                .frame(maxWidth: .infinity)
                                .padding()
                                .background(Color.blue.opacity(0.7))
                                .foregroundColor(.white)
                                .cornerRadius(8)
                        })
                    }
                    .padding(.horizontal)
                }
                .padding()
                .background(Color.white)
                .cornerRadius(12)
                .padding(40)
            }
        }
    }
}
struct ContentView_Previews: PreviewProvider {
    static var previews: some View {
        ContentView()
    }
}