export class ValueComparator {
  static valueComparator(v1, v2): boolean {
    if (typeof v1 === 'object' && typeof v2 === 'object') {
      return ObjectUtil.equals(v1, v2);
    } else if (v1 === v2) {
      return true;
    } else if (!v1 && !v2) {
      return true;
    }
    return false;
  }
}
class ObjectUtil {
  public static equals(a: any, b: any): boolean {
    const countProps = (obj) => {
      let count = 0;
      for (const k in obj) {
        if (obj.hasOwnProperty(k)) {
          count++;
        }
      }
      return count;
    };
    const objectEquals = (v1: any, v2: any) => {
      if (typeof (v1) !== typeof (v2)) {
        return false;
      }
      if (typeof (v1) === 'function') {
        return v1.toString() === v2.toString();
      }
      if (v1 instanceof Object && v2 instanceof Object) {
        if (countProps(v1) !== countProps(v2)) {
          return false;
        }
        let r = true;
        for (const k in v1) {
          r = objectEquals(v1[k], v2[k]);
          if (!r) {
            return false;
          }
        }
        return true;
      } else {
        return v1 === v2;
      }
    };
    return objectEquals(a, b);
  }
  public static getPropDiff(newObj: {}, oldObj: {}): string[] {
    return Object.keys(newObj).reduce<string[]>((acc: string[], key) => {
      if (ObjectUtil.equals(newObj[key], oldObj[key])) {
        return acc;
      }
      acc.push(key);
      return acc;
    }, []);
  }
  public static getTruthyProps(obj: {}): string[] {
    return Object.keys(obj).filter((key) => !!obj[key]);
  }
  public static toOrderedString(obj: {}): string {
    return JSON.stringify(Object.keys(obj).sort().reduce<{}>((acc, k) => {
      acc[k] = obj[k];
      return acc;
    }, {}));
  }
}