//
//  MapViewController.swift
//  Runner
//
//  Created by Groot on 2025/5/7.
//

import UIKit
import MapKit
import Combine

class MapViewController: UIViewController {
    
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
    
    let viewModel: MapViewModel
    let mapView = MKMapView()
    private var cancellables = Set<AnyCancellable>()
    
    init(viewModel: MapViewModel) {
        self.viewModel = viewModel
        super.init(nibName: nil, bundle: nil)
    }

    override func viewDidLoad() {
        super.viewDidLoad()
        setupView()
        setupMap()
        bindViewModel()
    }

    private func setupView() {
        mapView.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(mapView)
        NSLayoutConstraint.activate([
            mapView.topAnchor.constraint(equalTo: view.topAnchor),
            mapView.bottomAnchor.constraint(equalTo: view.bottomAnchor),
            mapView.leadingAnchor.constraint(equalTo: view.leadingAnchor),
            mapView.trailingAnchor.constraint(equalTo: view.trailingAnchor)
        ])
    }

    private func setupMap() {
        mapView.delegate = self
        mapView.showsUserLocation = true
        mapView.setUserTrackingMode(.follow, animated: true)
    }
    
    private func bindViewModel() {
        // 监听区域变化并更新地图
        viewModel.$currentRegion
            .compactMap { $0 }
            .sink { [weak self] region in
                self?.mapView.setRegion(region, animated: true)
            }
            .store(in: &cancellables)

        viewModel.$markers
            .sink { [weak self] markers in
                self?.mapView.removeAnnotations(self?.mapView.annotations ?? [])
                self?.mapView.addAnnotations(markers)
            }
            .store(in: &cancellables)

        viewModel.$polylines
            .sink { [weak self] polylines in
                self?.mapView.removeOverlays(self?.mapView.overlays ?? [])
                self?.mapView.addOverlays(polylines.map({ $0.polyline }))
            }
            .store(in: &cancellables)
    }
}

extension MapViewController: MKMapViewDelegate {
    func mapView(_ mapView: MKMapView, viewFor annotation: MKAnnotation) -> MKAnnotationView? {
        var annotationView = mapView.dequeueReusableAnnotationView(withIdentifier: MapAnnotationView.identifier) as? MapAnnotationView
        
        // 如果没有可复用的视图，创建新的自定义标注视图
        if annotationView == nil {
            annotationView = MapAnnotationView(annotation: annotation, reuseIdentifier: MapAnnotationView.identifier)
        } else {
            // 更新现有视图的标注
            annotationView?.annotation = annotation
        }
        
        return annotationView
    }

    func mapView(_ mapView: MKMapView, didSelect view: MKAnnotationView) {
        guard var marker = view.annotation as? ATMapMarker else {
            return
        }
        
        viewModel.handleMarkerTap(marker: &marker)
    }

    func mapView(_ mapView: MKMapView, rendererFor overlay: MKOverlay) -> MKOverlayRenderer {
        let renderer = MKPolylineRenderer(overlay: overlay)
        renderer.lineWidth = 5
        renderer.strokeColor = .blue
        renderer.alpha = 1
        renderer.lineCap = .round
        renderer.lineJoin = .round
        return renderer
    }
}