import { existsSync } from "node:fs";
import { resolve, isAbsolute } from "node:path";

// IMPORTANT: this module imports `node:fs` / `node:path` and must NEVER be
// re-exported from the main `@pipeline/shared` barrel (which client bundles
// import). Reach it only via the `@pipeline/shared/node` subpath.

// Files that mark the monorepo root. Used so CLI (cwd = repo root) and the web
// app (cwd = apps/web) — and the Docker container (cwd = /app/apps/web) — all
// resolve the same unified output directory.
const ROOT_MARKERS = ["pnpm-workspace.yaml", "turbo.json"];

/**
 * Walk up from `from` (default: cwd) until a monorepo marker file is found.
 * Falls back to `from` when no marker is discovered (e.g. running outside the repo).
 */
export function findMonorepoRoot(from: string = process.cwd()): string {
  let dir = resolve(from);
  for (let i = 0; i < 8; i++) {
    if (ROOT_MARKERS.some((m) => existsSync(resolve(dir, m)))) {
      return dir;
    }
    const parent = resolve(dir, "..");
    if (parent === dir) break;
    dir = parent;
  }
  return resolve(from);
}

/**
 * Resolve the unified output base directory.
 *
 * Resolution order: `OUTPUT_DIR` env var > `configured` (config/default.yaml
 * `output.dir`) > `./output`. Relative paths are resolved against the monorepo
 * root (not cwd), so CLI / HTTP / web all land in the same physical directory.
 */
export function resolveOutputDir(configured?: string): string {
  const raw = process.env.OUTPUT_DIR || configured || "./output";
  return isAbsolute(raw) ? raw : resolve(findMonorepoRoot(), raw);
}