49 lines
1.2 KiB
TypeScript
49 lines
1.2 KiB
TypeScript
import * as crypto from "node:crypto";
|
|
import * as later from "@breejs/later";
|
|
|
|
function md532(str): number {
|
|
const digest = crypto.createHash("md5").update(str).digest();
|
|
return (
|
|
digest.readUInt32LE(0) ^
|
|
digest.readUInt32LE(4) ^
|
|
digest.readUInt32LE(8) ^
|
|
digest.readUInt32LE(12)
|
|
);
|
|
}
|
|
|
|
export function variance(deviceId: string, vrnc: number): number {
|
|
return (md532(deviceId) >>> 0) % vrnc;
|
|
}
|
|
|
|
export function interval(
|
|
timestamp: number,
|
|
intrvl: number,
|
|
offset = 0,
|
|
): number {
|
|
return Math.trunc((timestamp + offset) / intrvl) * intrvl - offset;
|
|
}
|
|
|
|
export function parseCron(cronExp: string): any {
|
|
const parts = cronExp.trim().split(/\s+/);
|
|
if (parts.length === 5) parts.unshift("*");
|
|
|
|
return later.schedule(later.parse.cron(parts.join(" "), true));
|
|
}
|
|
|
|
export function cron(
|
|
timestamp: number,
|
|
schedule: unknown,
|
|
offset = 0,
|
|
): number[] {
|
|
// TODO later.js doesn't throw erorr if expression is invalid!
|
|
const ret = [0, 0];
|
|
|
|
const prev = (schedule as any).prev(1, new Date(timestamp + offset));
|
|
if (prev) ret[0] = prev.setMilliseconds(0) - offset;
|
|
|
|
const next = (schedule as any).next(1, new Date(timestamp + offset + 1000));
|
|
if (next) ret[1] = next.setMilliseconds(0) - offset;
|
|
|
|
return ret;
|
|
}
|