mapcomplete/Logic/FeatureSource/FilteringFeatureSource.ts
2021-01-05 11:17:12 +01:00

66 lines
No EOL
2.3 KiB
TypeScript

import FeatureSource from "./FeatureSource";
import {UIEventSource} from "../UIEventSource";
import LayerConfig from "../../Customizations/JSON/LayerConfig";
import Loc from "../../Models/Loc";
export default class FilteringFeatureSource implements FeatureSource {
public features: UIEventSource<{ feature: any; freshness: Date }[]> = new UIEventSource<{ feature: any; freshness: Date }[]>([]);
constructor(layers: {
isDisplayed: UIEventSource<boolean>,
layerDef: LayerConfig
}[],
location: UIEventSource<Loc>,
upstream: FeatureSource) {
const layerDict = {};
const self = this;
function update() {
const features: { feature: any, freshness: Date }[] = upstream.features.data;
const newFeatures = features.filter(f => {
const layerId = f.feature._matching_layer_id;
if (layerId === undefined) {
console.error(f)
throw "feature._matching_layer_id is undefined"
}
const layer: {
isDisplayed: UIEventSource<boolean>,
layerDef: LayerConfig
} = layerDict[layerId];
if (layer === undefined) {
throw "No layer found with id " + layerId;
}
return layer.isDisplayed.data && (layer.layerDef.minzoom <= location.data.zoom);
});
self.features.setData(newFeatures);
}
for (const layer of layers) {
layerDict[layer.layerDef.id] = layer;
}
upstream.features.addCallback(() => {
update()});
location.map(l => {
// We want something that is stable for the shown layers
const displayedLayerIndexes = [];
for (let i = 0; i < layers.length; i++) {
if(l.zoom < layers[i].layerDef.minzoom){
continue;
}
if(!layers[i].isDisplayed.data){
continue;
}
displayedLayerIndexes.push(i);
}
return displayedLayerIndexes.join(",")
}, layers.map(l => l.isDisplayed))
.addCallback(() => {
update();});
}
}