122 lines
3.3 KiB
TypeScript
122 lines
3.3 KiB
TypeScript
import * as plugins from './smartstate.plugins.js';
|
|
import { StateAction, IActionDef } from './smartstate.classes.stateaction.js';
|
|
|
|
export class StatePart<TStatePartName, TStatePayload> {
|
|
public name: TStatePartName;
|
|
public state = new plugins.smartrx.rxjs.Subject<TStatePayload>();
|
|
public stateStore: TStatePayload;
|
|
private cumulativeDeferred = plugins.smartpromise.cumulativeDefer();
|
|
|
|
constructor(nameArg: TStatePartName) {
|
|
this.name = nameArg;
|
|
}
|
|
|
|
/**
|
|
* gets the state from the state store
|
|
*/
|
|
public getState(): TStatePayload {
|
|
return this.stateStore;
|
|
}
|
|
|
|
/**
|
|
* sets the stateStore to the new state
|
|
* @param newStateArg
|
|
*/
|
|
public setState(newStateArg: TStatePayload) {
|
|
this.stateStore = newStateArg;
|
|
this.notifyChange();
|
|
}
|
|
|
|
/**
|
|
* notifies of a change on the state
|
|
*/
|
|
public notifyChange() {
|
|
const createStateHash = (stateArg: any) => {
|
|
return plugins.isohash.sha256FromString(plugins.smartjson.stringify(stateArg));
|
|
};
|
|
if (
|
|
this.stateStore &&
|
|
this.lastStateNotificationPayloadHash &&
|
|
createStateHash(this.stateStore) === createStateHash(this.lastStateNotificationPayloadHash)
|
|
) {
|
|
return;
|
|
} else {
|
|
this.lastStateNotificationPayloadHash = this.stateStore;
|
|
}
|
|
this.state.next(this.stateStore);
|
|
}
|
|
private lastStateNotificationPayloadHash: any;
|
|
|
|
/**
|
|
* selects a state or a substate
|
|
*/
|
|
public select<T = TStatePayload>(
|
|
selectorFn?: (state: TStatePayload) => T
|
|
): plugins.smartrx.rxjs.Observable<T> {
|
|
if (!selectorFn) {
|
|
selectorFn = (state: TStatePayload) => <T>(<any>state);
|
|
}
|
|
|
|
const mapped = this.state.pipe(
|
|
plugins.smartrx.rxjs.ops.startWith(this.getState()),
|
|
plugins.smartrx.rxjs.ops.map((stateArg) => {
|
|
try {
|
|
return selectorFn(stateArg);
|
|
} catch (e) {
|
|
// Nothing here
|
|
}
|
|
})
|
|
);
|
|
|
|
return mapped;
|
|
}
|
|
|
|
/**
|
|
* creates an action capable of modifying the state
|
|
*/
|
|
public createAction<TActionPayload>(
|
|
actionDef: IActionDef<TStatePayload, TActionPayload>
|
|
): StateAction<TStatePayload, TActionPayload> {
|
|
return new StateAction(this, actionDef);
|
|
}
|
|
|
|
/**
|
|
* dispatches an action on the statepart level
|
|
*/
|
|
public async dispatchAction<T>(stateAction: StateAction<TStatePayload, T>, actionPayload: T) {
|
|
await this.cumulativeDeferred.promise;
|
|
const newState = await stateAction.actionDef(this, actionPayload);
|
|
this.setState(newState);
|
|
}
|
|
|
|
/**
|
|
* waits until a certain part of the state becomes available
|
|
* @param selectorFn
|
|
*/
|
|
public async waitUntilPresent<T = TStatePayload>(
|
|
selectorFn?: (state: TStatePayload) => T
|
|
): Promise<T> {
|
|
const done = plugins.smartpromise.defer<T>();
|
|
const selectedObservable = this.select(selectorFn);
|
|
const subscription = selectedObservable.subscribe(async (value) => {
|
|
if (value) {
|
|
done.resolve(value);
|
|
}
|
|
});
|
|
const result = await done.promise;
|
|
subscription.unsubscribe();
|
|
return result;
|
|
}
|
|
|
|
/**
|
|
* is executed
|
|
*/
|
|
public async stateSetup(
|
|
funcArg: (statePartArg?: StatePart<any, TStatePayload>) => Promise<TStatePayload>
|
|
) {
|
|
const resultPromise = funcArg(this);
|
|
this.cumulativeDeferred.addPromise(resultPromise);
|
|
this.setState(await resultPromise);
|
|
}
|
|
}
|