import { randomBytes, createHash } from 'node:crypto';
/**
* Base64URL encoding according to RFC 7636
*/
export const base64URLEncode = (buffer: Buffer): string => {
return buffer.toString('base64').replace(/\+/g, '-').replace(/\//g, '_').replace(/=/g, '');
};
/**
* Generates a cryptographically secure random string for OAuth state parameter
* Uses hex encoding for better compatibility
*/
export const generateRandomState = (): string => {
return randomBytes(20).toString('hex');
};
/**
* Generates a random port number between min and max (inclusive), excluding specified (already used) ports
* @param min Minimum port number (default: 5344)
* @param max Maximum port number (default: 5349)
* @param excludePorts Array of port numbers to exclude (e.g., already used ports)
* @returns A random port number between min and max, excluding already used ports
*/
export const getRandomPort = (min = 5344, max = 5349, excludePorts: number[] = []): number => {
// ensure that we have at least one port to choose from
if (excludePorts.length >= max - min + 1) {
throw new Error('No available ports to choose from');
}
// pick a random port between max and min
let port: number;
do {
port = Math.floor(Math.random() * (max - min + 1)) + min;
// keep iterating until we find a port that is not in the excludePorts list
} while (excludePorts.includes(port));
return port;
};
