import { isAbsolute, join, normalize, relative } from "@std/path";
import type { BuyerDocument } from "./types.ts";

export function resolvePdfPath(
  baseDirectory: string,
  doc: BuyerDocument,
): string {
  if (!baseDirectory.trim()) {
    throw new Error("PDF base directory is not configured.");
  }
  if (!isAbsolute(baseDirectory)) {
    throw new Error("PDF base directory must be absolute.");
  }

  const base = normalize(baseDirectory);
  const full = normalize(join(base, doc._letter, doc.file_name));
  const rel = relative(base, full);
  if (rel.startsWith("..") || isAbsolute(rel)) {
    throw new Error("Resolved PDF path escapes the base directory.");
  }
  return full;
}