mapcomplete/Logic/Leaflet/Basemap.ts

import * as L from "leaflet"
import {UIEventSource} from "../UIEventSource";
import {UIElement} from "../../UI/UIElement";
import {BaseLayer} from "../../Models/BaseLayer";
import AvailableBaseLayers from "../Actors/AvailableBaseLayers";
import Loc from "../../Models/Loc";

export class Basemap {


    // @ts-ignore
    public readonly map: Map;

    public readonly LastClickLocation: UIEventSource<{ lat: number, lon: number }> = new UIEventSource<{ lat: number, lon: number }>(undefined)


    constructor(leafletElementId: string,
                location: UIEventSource<Loc>,
                currentLayer: UIEventSource<BaseLayer>,
                extraAttribution: UIElement) {
        this.map = L.map(leafletElementId, {
            center: [location.data.lat ?? 0, location.data.lon ?? 0],
            zoom: location.data.zoom ?? 2,
            layers: [AvailableBaseLayers.osmCarto.layer],
        });

        L.control.scale(
            {
                position: 'topright',
            }
        ).addTo(this.map)


        // Users are not allowed to zoom to the 'copies' on the left and the right, stuff goes wrong then
        // We give a bit of leeway for people on the edges
        // Also see: https://www.reddit.com/r/openstreetmap/comments/ih4zzc/mapcomplete_a_new_easytouse_editor/g31ubyv/
        this.map.setMaxBounds(
            [[-100, -200], [100, 200]]
        );
        this.map.attributionControl.setPrefix(
            extraAttribution.Render() + " | <a href='https://osm.org'>OpenStreetMap</a>");

        this.map.zoomControl.setPosition("bottomright");
        const self = this;

        let previousLayer = currentLayer.data;
        currentLayer.addCallbackAndRun(layer => {
            if (layer === previousLayer) {
                return;
            }
            if (previousLayer !== undefined) {
                self.map.removeLayer(previousLayer.layer);
            }
            previousLayer = layer;
            self.map.addLayer(layer.layer);
        })


        this.map.on("moveend", function () {
            location.data.zoom = self.map.getZoom();
            location.data.lat = self.map.getCenter().lat;
            location.data.lon = self.map.getCenter().lng;
            location.ping();
        });

        this.map.on("click", function (e) {
            self.LastClickLocation.setData({lat: e.latlng.lat, lon: e.latlng.lng})
        });

        this.map.on("contextmenu", function (e) {
            self.LastClickLocation.setData({lat: e.latlng.lat, lon: e.latlng.lng});
            e.preventDefault();
        });


    }


}