import { done } from './util';
export function debounce(delay: number): Function {
return decorate((fn, key) => {
const timerKey = `$debounce$${key}`;
return function (this: any, ...args: any[]) {
clearTimeout(this[timerKey]);
this[timerKey] = setTimeout(() => fn.apply(this, args), delay);
};
});
}
export const throttle = decorate(_throttle);
function _throttle<T>(fn: Function, key: string): Function {
const currentKey = `$throttle$current$${key}`;
const nextKey = `$throttle$next$${key}`;
const trigger = function (this: any, ...args: any[]) {
if (this[nextKey]) {
return this[nextKey];
}
if (this[currentKey]) {
this[nextKey] = done(this[currentKey]).then(() => {
this[nextKey] = undefined;
return trigger.apply(this, args);
});
return this[nextKey];
}
this[currentKey] = fn.apply(this, args) as Promise<T>;
const clear = () => this[currentKey] = undefined;
done(this[currentKey]).then(clear, clear);
return this[currentKey];
};
return trigger;
}
function decorate(decorator: (fn: Function, key: string) => Function): Function {
return function (original: any, context: ClassMethodDecoratorContext) {
if (context.kind !== 'method') {
throw new Error('not supported');
}
return decorator(original, context.name.toString());
};
}
