import { normalizeFilesPath, type NormalizedDavPath } from "@/worker/dav/paths";

export type DestinationResult = { ok: true; path: NormalizedDavPath } | { ok: false; status: number; message: string };

export function parseDestination(headerValue: string | null, requestUrl: URL): DestinationResult {
  if (!headerValue) return { ok: false, status: 400, message: "Missing Destination header" };

  let destinationUrl: URL;
  try {
    destinationUrl = headerValue.startsWith("/") ? new URL(headerValue, requestUrl) : new URL(headerValue);
  } catch {
    return { ok: false, status: 400, message: "Invalid Destination header" };
  }

  if (destinationUrl.host.toLowerCase() !== requestUrl.host.toLowerCase()) {
    return { ok: false, status: 502, message: "Cross-host COPY and MOVE are not supported" };
  }

  const normalized = normalizeFilesPath(destinationUrl.pathname);
  if (!normalized.ok) return normalized;
  return { ok: true, path: normalized.path };
}

export function overwriteAllowed(headerValue: string | null): boolean | null {
  if (headerValue === null || headerValue === "") return true;
  const value = headerValue.toUpperCase();
  if (value === "T") return true;
  if (value === "F") return false;
  return null;
}