112 lines
3.8 KiB
TypeScript
112 lines
3.8 KiB
TypeScript
import { UIEventSource } from "../../UIEventSource"
|
|
import FeatureSource, { FeatureSourceForLayer, IndexedFeatureSource, Tiled } from "../FeatureSource"
|
|
import FilteredLayer from "../../../Models/FilteredLayer"
|
|
import { Tiles } from "../../../Models/TileRange"
|
|
import { BBox } from "../../BBox"
|
|
|
|
export default class FeatureSourceMerger
|
|
implements FeatureSourceForLayer, Tiled, IndexedFeatureSource
|
|
{
|
|
public features: UIEventSource<{ feature: any; freshness: Date }[]> = new UIEventSource<
|
|
{ feature: any; freshness: Date }[]
|
|
>([])
|
|
public readonly name
|
|
public readonly layer: FilteredLayer
|
|
public readonly tileIndex: number
|
|
public readonly bbox: BBox
|
|
public readonly containedIds: UIEventSource<Set<string>> = new UIEventSource<Set<string>>(
|
|
new Set()
|
|
)
|
|
private readonly _sources: UIEventSource<FeatureSource[]>
|
|
/**
|
|
* Merges features from different featureSources for a single layer
|
|
* Uses the freshest feature available in the case multiple sources offer data with the same identifier
|
|
*/
|
|
constructor(
|
|
layer: FilteredLayer,
|
|
tileIndex: number,
|
|
bbox: BBox,
|
|
sources: UIEventSource<FeatureSource[]>
|
|
) {
|
|
this.tileIndex = tileIndex
|
|
this.bbox = bbox
|
|
this._sources = sources
|
|
this.layer = layer
|
|
this.name =
|
|
"FeatureSourceMerger(" +
|
|
layer.layerDef.id +
|
|
", " +
|
|
Tiles.tile_from_index(tileIndex).join(",") +
|
|
")"
|
|
const self = this
|
|
|
|
const handledSources = new Set<FeatureSource>()
|
|
|
|
sources.addCallbackAndRunD((sources) => {
|
|
let newSourceRegistered = false
|
|
for (let i = 0; i < sources.length; i++) {
|
|
let source = sources[i]
|
|
if (handledSources.has(source)) {
|
|
continue
|
|
}
|
|
handledSources.add(source)
|
|
newSourceRegistered = true
|
|
source.features.addCallback(() => {
|
|
self.Update()
|
|
})
|
|
if (newSourceRegistered) {
|
|
self.Update()
|
|
}
|
|
}
|
|
})
|
|
}
|
|
|
|
private Update() {
|
|
let somethingChanged = false
|
|
const all: Map<string, { feature: any; freshness: Date }> = new Map<
|
|
string,
|
|
{ feature: any; freshness: Date }
|
|
>()
|
|
// We seed the dictionary with the previously loaded features
|
|
const oldValues = this.features.data ?? []
|
|
for (const oldValue of oldValues) {
|
|
all.set(oldValue.feature.id, oldValue)
|
|
}
|
|
|
|
for (const source of this._sources.data) {
|
|
if (source?.features?.data === undefined) {
|
|
continue
|
|
}
|
|
for (const f of source.features.data) {
|
|
const id = f.feature.properties.id
|
|
if (!all.has(id)) {
|
|
// This is a new feature
|
|
somethingChanged = true
|
|
all.set(id, f)
|
|
continue
|
|
}
|
|
|
|
// This value has been seen already, either in a previous run or by a previous datasource
|
|
// Let's figure out if something changed
|
|
const oldV = all.get(id)
|
|
if (oldV.freshness < f.freshness) {
|
|
// Jup, this feature is fresher
|
|
all.set(id, f)
|
|
somethingChanged = true
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!somethingChanged) {
|
|
// We don't bother triggering an update
|
|
return
|
|
}
|
|
|
|
const newList = []
|
|
all.forEach((value, _) => {
|
|
newList.push(value)
|
|
})
|
|
this.containedIds.setData(new Set(all.keys()))
|
|
this.features.setData(newList)
|
|
}
|
|
}
|