enum.ts

/**
 * The standard enum type
 */
export type StandardEnum<T> = {
  [id: string]: T | string;
  [nu: number]: string;
};

/**
 * Returns the name of an enum from its value
 * @param enumVariable The enum for which you want to get the name
 * @param enumValue The value of the enum for which you want to get the name
 * @returns A string containing the name of the enum
 */
export function getEnumNameFromValue<T>(enumVariable: StandardEnum<T>, enumValue: T): string {
  let result = enumVariable[enumValue as keyof StandardEnum<T>] as string;

  if (result === undefined && isEnumString(enumVariable)) {
    result = Object.keys(enumVariable)[Object.values(enumVariable).indexOf(enumValue)];
  }

  return result;
}

/**
 * Returns the value of an enum from its name
 * @param enumVariable The enum for which you want to get the value
 * @param enumName The name of the enum for which you want to get the value
 * @returns A string containing the value of the enum
 */
export function getEnumValueFromName<T>(enumVariable: StandardEnum<T>, enumName: string): T {
  return enumVariable[enumName as keyof StandardEnum<T>] as T;
}

/**
 * Returns all the names of an enum
 * @param enumVariable The enum for which you want to get the names
 * @returns A string array containing the names of the enum
 */
export function getEnumNames<T>(enumVariable: StandardEnum<T>) {
  const names = Object.values(enumVariable);

  // If enum is with values integer, object.values returns a list of [names, values].
  return isEnumString(enumVariable) ? Object.keys(enumVariable) : names.slice(0, names.length / 2);
}

/**
 * Returns all the values of an enum
 * @param enumVariable The enum for which you want to get the values
 * @returns A string or number array containing the values of the enum
 */
export function getEnumValues<T>(enumVariable: StandardEnum<T>): T[] {
  const keys = Object.keys(enumVariable);

  // If enum is with values integer, object.keys returns a list of [values, names].
  return (
    isEnumString(enumVariable) ? Object.values(enumVariable) : keys.slice(0, keys.length / 2).map((value) => Number.parseInt(value))
  ) as T[];
}

/**
 * Parses a string to an enum value
 * @param enumVariable The enum for which you want to get the values
 * @param value The string to parse
 * @returns The enum value corresponding to the string, or undefined if not found
 */
export function parseEnum<T>(enumVariable: StandardEnum<T>, value: string): T | undefined {
  if (!isEnumString(enumVariable) && Number.isNaN(Number(value))) {
    return undefined;
  }

  return getEnumValueFromName(enumVariable, getEnumNameFromValue(enumVariable, value as T));
}

/**
 * Returns if it's a enum with string value
 * @param enumVariable The enum
 * @returns A bool
 */
function isEnumString<T>(enumVariable: StandardEnum<T>) {
  for (const key in enumVariable) {
    return !/^\d+$/.test(key);
  }

  return false;
}