// State persistence: the plugin writes under `<config_dir>/plugin-state/rom-manager`, and on first
// run migrates an operator config authored in the pre-0.2.1 `<config_dir>/rom-manager` location —
// the write path moved when the runner was de-privileged, and a missed migration would silently
// reset the operator's settings.
import { afterEach, beforeEach, describe, expect, test } from "bun:test";
import * as fs from "node:fs";
import * as os from "node:os";
import * as path from "node:path";
import { loadConfig, saveRawConfig } from "../src/state.js";

let root: string;
let saved: string | undefined;

beforeEach(() => {
	saved = process.env.PUNKTFUNK_CONFIG_DIR;
	root = fs.mkdtempSync(path.join(os.tmpdir(), "rm-state-"));
	process.env.PUNKTFUNK_CONFIG_DIR = root;
});
afterEach(() => {
	if (saved === undefined) delete process.env.PUNKTFUNK_CONFIG_DIR;
	else process.env.PUNKTFUNK_CONFIG_DIR = saved;
	fs.rmSync(root, { recursive: true, force: true });
});

describe("state location + migration", () => {
	test("persists under plugin-state/rom-manager", () => {
		saveRawConfig({ roots: [{ dir: "/games", platform: "snes" }] });
		expect(
			fs.existsSync(
				path.join(root, "plugin-state", "rom-manager", "config.json"),
			),
		).toBe(true);
	});

	test("migrates a pre-0.2.1 config from <config_dir>/rom-manager on first load", () => {
		// An operator config authored in the OLD location.
		const legacy = path.join(root, "rom-manager");
		fs.mkdirSync(legacy, { recursive: true });
		fs.writeFileSync(
			path.join(legacy, "config.json"),
			JSON.stringify({ roots: [{ dir: "/legacy/games", platform: "snes" }] }),
		);
		// First load migrates it — the operator's roots survive rather than resetting to defaults.
		const cfg = loadConfig();
		expect(cfg.roots).toEqual([{ dir: "/legacy/games", platform: "snes" }]);
		expect(
			fs.existsSync(
				path.join(root, "plugin-state", "rom-manager", "config.json"),
			),
		).toBe(true);
	});

	test("does not clobber an existing new-location config with the legacy one", () => {
		const legacy = path.join(root, "rom-manager");
		fs.mkdirSync(legacy, { recursive: true });
		fs.writeFileSync(
			path.join(legacy, "config.json"),
			JSON.stringify({ roots: [{ dir: "/old", platform: "snes" }] }),
		);
		saveRawConfig({ roots: [{ dir: "/new", platform: "snes" }] }); // new location already authored
		expect(loadConfig().roots).toEqual([{ dir: "/new", platform: "snes" }]);
	});
});