Function parseJumpHost

src/utils/ssh-config-parser.ts:261–326

(jumpHostStr: string)

 * @throws Error if the input is empty or results in an empty/invalid host
 */
export function parseJumpHost(jumpHostStr: string): JumpHost {
  let username: string | undefined;
  let host: string;
  let port = 22;

  let remaining = jumpHostStr.trim();

  // Validate input is not empty
  if (!remaining) {
    throw new Error('Jump host string cannot be empty');
  }

  // Extract username if present (user@...)
  const atIndex = remaining.indexOf('@');
  if (atIndex !== -1) {
    const extractedUsername = remaining.substring(0, atIndex).trim();
    // Only set username if non-empty (handles case like "@host" or " @host")
    if (extractedUsername) {
      username = extractedUsername;
    }
    remaining = remaining.substring(atIndex + 1);
  }

  // Extract port if present (...:port)
  // Be careful with IPv6 addresses like [::1]:22
  if (remaining.startsWith('[')) {
    // IPv6 address in brackets
    const closeBracket = remaining.indexOf(']');
    if (closeBracket !== -1) {
      host = remaining.substring(1, closeBracket);
      const afterBracket = remaining.substring(closeBracket + 1);
      if (afterBracket.startsWith(':')) {
        const parsedPort = parseInt(afterBracket.substring(1), 10);
        validatePort(parsedPort, jumpHostStr);
        port = parsedPort;
      }
    } else {
      // Malformed IPv6 address: missing closing bracket
      throw new Error(`Invalid ProxyJump host "${jumpHostStr}": missing closing bracket in IPv6 address`);
    }
  } else {
    // Regular hostname or IPv4
    const lastColon = remaining.lastIndexOf(':');
    if (lastColon !== -1) {
      const potentialPort = remaining.substring(lastColon + 1);
      // Only treat as port if it's a valid number
      if (/^\d+$/.test(potentialPort)) {
        host = remaining.substring(0, lastColon);
        const parsedPort = parseInt(potentialPort, 10);
        validatePort(parsedPort, jumpHostStr);
        port = parsedPort;
      } else {
        host = remaining;
      }
    } else {
      host = remaining;
    }
  }