breakout71/src/getLevelBackground.ts

import { RawLevel } from "./types";

import _backgrounds from "./data/backgrounds.json";
const backgrounds = _backgrounds as string[];

export function getLevelBackground(level: RawLevel) {
  let svg = level.svg !== null && backgrounds[level.svg % backgrounds.length];

  if (!level.color && !svg) {
    svg = backgrounds[hashCode(level.name) % backgrounds.length];
  }
  return svg;
}

export function hashCode(string: string) {
  let hash = 0;
  for (let i = 0; i < string.length; i++) {
    let code = string.charCodeAt(i);
    hash = (hash << 5) - hash + code;
    hash = hash & hash; // Convert to 32bit integer
  }
  return Math.abs(hash);
}