/**
 * Shared queue storage layout for pi extensions (HUD + pi-queue).
 *
 * One file per session, keyed by sha1(sessionFile). The legacy `queue.json`
 * is read once on first load in a new session and emptied; new writes go to
 * the per-session file.
 *
 * ponytail: session id is sha1(sessionFile). Upgrade path: switch to a stable
 * id (e.g. homedir-relative basename) if we ever need cross-device resolution.
 */

import { createHash } from "node:crypto";
import { homedir } from "node:os";
import { join } from "node:path";

const PI_ROOT = process.env.PI_HOME || join(homedir(), ".pi");

/** Directory that holds per-session queue files plus the legacy queue.json. */
export const QUEUE_STATE_DIR = join(PI_ROOT, "agent", "pi-queue");

/** Pre-refactor single-file path. Read once then emptied. */
export const QUEUE_LEGACY_FILE = join(QUEUE_STATE_DIR, "queue.json");

export function queueFileFor(sessionFile: string | undefined): string {
	const seed = sessionFile || process.cwd() || "global";
	const hash = createHash("sha1").update(seed).digest("hex").slice(0, 16);
	return join(QUEUE_STATE_DIR, `${hash}.json`);
}