mapcomplete/Logic/UIEventSource.ts
2020-10-11 22:44:58 +02:00

131 lines
No EOL
3.7 KiB
TypeScript

export class UIEventSource<T>{
public data: T;
private _callbacks = [];
constructor(data: T) {
this.data = data;
}
public addCallback(callback: ((latestData: T) => void)): UIEventSource<T> {
if(callback === console.log){
// This ^^^ actually works!
throw "Don't add console.log directly as a callback - you'll won't be able to find it afterwards. Wrap it in a lambda instead."
}
this._callbacks.push(callback);
return this;
}
public addCallbackAndRun(callback: ((latestData: T) => void)): UIEventSource<T> {
callback(this.data);
return this.addCallback(callback);
}
public setData(t: T): UIEventSource<T> {
if (this.data === t) {
return;
}
this.data = t;
this.ping();
return this;
}
public ping(): void {
for (const callback of this._callbacks) {
callback(this.data);
}
}
public static flatten<X>(source: UIEventSource<UIEventSource<X>>, possibleSources: UIEventSource<any>[]): UIEventSource<X> {
const sink = new UIEventSource<X>(source.data?.data);
source.addCallback((latestData) => {
sink.setData(latestData?.data);
});
for (const possibleSource of possibleSources) {
possibleSource?.addCallback(() => {
sink.setData(source.data?.data);
})
}
return sink;
}
public map<J>(f: ((T) => J),
extraSources: UIEventSource<any>[] = [],
g: ((J) => T) = undefined ): UIEventSource<J> {
const self = this;
const newSource = new UIEventSource<J>(
f(this.data)
);
const update = function () {
newSource.setData(f(self.data));
}
this.addCallbackAndRun(update);
for (const extraSource of extraSources) {
extraSource?.addCallback(update);
}
if(g !== undefined) {
newSource.addCallback((latest) => {
self.setData(g(latest));
})
}
return newSource;
}
public syncWith(otherSource: UIEventSource<T>, reverseOverride = false): UIEventSource<T> {
this.addCallback((latest) => otherSource.setData(latest));
const self = this;
otherSource.addCallback((latest) => self.setData(latest));
if (reverseOverride && otherSource.data !== undefined) {
this.setData(otherSource.data);
} else if (this.data === undefined) {
this.setData(otherSource.data);
} else {
otherSource.setData(this.data);
}
return this;
}
public stabilized(millisToStabilize) : UIEventSource<T>{
const newSource = new UIEventSource<T>(this.data);
let currentCallback = 0;
this.addCallback(latestData => {
currentCallback++;
const thisCallback = currentCallback;
window.setTimeout(() => {
if(thisCallback === currentCallback){
newSource.setData(latestData);
}
}, millisToStabilize)
});
return newSource;
}
public static Chronic(millis: number, asLong: () => boolean = undefined): UIEventSource<Date> {
const source = new UIEventSource<Date>(undefined);
function run() {
source.setData(new Date());
if (asLong === undefined || asLong()) {
window.setTimeout(run, millis);
}
}
run();
return source;
}
}