random.js

/** Monster 1.9.0, © 2021 schukai GmbH, Released under the AGPL 3.0 License. */
'use strict';import{Monster,getGlobal}from"../types/global.js";function random(min,max){if(min===undefined){min=0}if(max===undefined){max=MAX}if(max<min){throw new Error("max must be greater than min")}return Math.round(create(min,max))}var MAX=1000000000;Math.log2=Math.log2||function(n){return Math.log(n)/Math.log(2)};function create(min,max){let crypt;let globalReference=getGlobal();crypt=globalReference?.["crypto"]||globalReference?.["msCrypto"]||globalReference?.["crypto"]||undefined;if(typeof crypt==="undefined"){throw new Error("missing crypt")}let rval=0;const range=max-min;if(range<2){return min}const bitsNeeded=Math.ceil(Math.log2(range));if(bitsNeeded>53){throw new Error("we cannot generate numbers larger than 53 bits.")}const bytesNeeded=Math.ceil(bitsNeeded/8);const mask=Math.pow(2,bitsNeeded)-1;const byteArray=new Uint8Array(bytesNeeded);crypt.getRandomValues(byteArray);let p=(bytesNeeded-1)*8;for(var i=0;i<bytesNeeded;i++){rval+=byteArray[i]*Math.pow(2,p);p-=8}rval=rval&mask;if(rval>=range){return create(min,max)}return min+rval}Monster.assignToNamespace("Monster.Math",random);export{Monster,random};