import { LatLng, LatLngExpression, LatLngTuple, LayerGroup, Marker, MarkerOptions, Polyline } from "leaflet";


export type TrackEventHandler = (track:Polyline)=>void;

export class TrackableMarker extends Marker {

    private tracks:Array<Polyline> = new Array();

    private initalTrackColor:string;

    private latestTrack:Polyline = null;

    private previousDoTrack:boolean = true;

    private previousColor: string;

    private trackLayers:LayerGroup = null;

    constructor(latlng:LatLngExpression,options?:MarkerOptions,trackColor?:string) {
        super(latlng,options)
        this.initalTrackColor = trackColor ?? '#3388ff';
        this.previousColor = this.initalTrackColor;
        this.trackLayers = new LayerGroup();
        this.latestTrack = new Polyline([latlng],{color:trackColor});
        this.latestTrack.addTo(this.trackLayers);
    }

    set TracksLayer(g:LayerGroup) {
        this.trackLayers = g;
    }

    trackForward(latlng:LatLngExpression,doTrack:boolean = true,trackColor?: string) {
        if(!doTrack) {
            this.previousDoTrack = doTrack;
            if(trackColor)
                this.previousColor = trackColor
            return;
        }

        if(!this.latestTrack) {
            this.latestTrack = new Polyline([latlng],{color:trackColor || this.previousColor});
            this.latestTrack.addTo(this.trackLayers);
            return;
        } else if(trackColor && this.latestTrack.options !== trackColor) {
            this.tracks.push(this.latestTrack)
            const lastLatLng: any = this.latestTrack.getLatLngs()[this.latestTrack.getLatLngs().length - 1]
            this.latestTrack = new Polyline([lastLatLng,latlng],{color:trackColor});
            this.latestTrack.addTo(this.trackLayers);
            this.previousColor = trackColor
            return;
        }


        if(this.previousDoTrack) {
            this.latestTrack.addLatLng(latlng);
        } else {
            this.tracks.push(this.latestTrack);
            this.latestTrack = new Polyline([latlng],{color:trackColor || this.previousColor});
            this.latestTrack.addTo(this.trackLayers);
        }
        this.previousDoTrack = doTrack;       
    }

    trackBackward(doTrack:boolean = true) {
        if(!doTrack) {
            return;
        }

        if(!this.latestTrack) {
            this.latestTrack = this.tracks.pop();
        }

        const latlngs = this.latestTrack.getLatLngs();

        if(latlngs.length <= 1) {
            this.trackLayers.removeLayer(this.latestTrack);
            this.latestTrack = this.tracks.pop();
            return;
        }
        this.latestTrack.setLatLngs(latlngs.slice(0,latlngs.length - 1));
    }

    removeTracks() {
        if(this.latestTrack) {
            this.trackLayers.removeLayer(this.latestTrack);
            this.latestTrack = null;
        }
        this.tracks.forEach((l) => this.trackLayers.removeLayer(l));
    }
}