/***
 * @module node-opcua-guid
 */
const regexGUID = /^[0-9A-Fa-f]{8}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{4}-[0-9A-Fa-f]{12}/;

/**
 * checks if provided string is a valid Guid
 * a valid GUID has the form  XXXXXXXX-XXXX-XXXX-XXXX-XXXXXXXX
 * when X is a hexadecimal digit
 *
 * @method isValidGuid
 * @param guid - the GUID to test for validaty
 * @return  - true if the string is a valid GUID.
 */
export function isValidGuid(guid: string): boolean {
    return regexGUID.test(guid);
}


//                                  1         2         3
//                        012345678901234567890123456789012345
export const emptyGuid = "00000000-0000-0000-0000-000000000000";

export function normalizeGuid(guid: Guid |null | undefined): Guid {
    return guid ? guid.toUpperCase() : emptyGuid;
}

export type Guid = string;