/** @file Storage paths module. */
import { mkdir, stat } from "node:fs/promises";
import { homedir } from "node:os";
import path from "node:path";

export interface PiStoragePaths {
	root: string;
	config: string;
	results: string;
	crawl: string;
	snapshots: string;
	jobs: string;
	downloads: string;
	/** Browser session storage state root (storage.json per sessionId). */
	sessions: string;
}

export interface ResolveStorageOptions {
	rootDir?: string;
}

export function expandHome(input: string): string {
	if (input === "~") return homedir();
	if (input.startsWith("~/")) return path.join(homedir(), input.slice(2));
	return input;
}

export function resolvePiStoragePaths(options: ResolveStorageOptions = {}): PiStoragePaths {
	const root = path.resolve(
		expandHome(options.rootDir ?? process.env.PI_SCRAPER_STORAGE_ROOT ?? "~/.pi/scraper"),
	);
	return {
		root,
		config: path.join(root, "config"),
		results: path.join(root, "results"),
		crawl: path.join(root, "crawl"),
		snapshots: path.join(root, "snapshots"),
		jobs: path.join(root, "jobs"),
		downloads: path.join(root, "downloads"),
		sessions: path.join(root, "sessions"),
	};
}

export async function ensureDir(dir: string): Promise<string> {
	await mkdir(dir, { recursive: true, mode: 0o700 });
	return dir;
}

export async function pathExists(filePath: string): Promise<boolean> {
	return await stat(filePath).then(
		() => true,
		() => false,
	);
}