import { describe, expect, test } from "bun:test";
import {
	type DetectEnv,
	detectEmulator,
	emulatorById,
} from "../src/domain/emulators.js";
import type { Os } from "../src/domain/quote.js";

const env = (o: {
	os?: Os;
	which?: Record<string, string>;
	files?: string[];
	flatpaks?: string[];
	dirs?: Record<string, string[]>;
}): DetectEnv => ({
	os: o.os ?? "linux",
	which: (c) => o.which?.[c] ?? null,
	fileExists: (p) => (o.files ?? []).includes(p),
	flatpakInstalled: (id) => (o.flatpaks ?? []).includes(id),
	listDir: (p) => o.dirs?.[p] ?? [],
	expandPath: (p) =>
		p
			.replace(/^~/, "/home/u")
			.replace(/%APPDATA%/, "C:\\Users\\u\\AppData\\Roaming")
			.replace(/%LOCALAPPDATA%/, "C:\\Users\\u\\AppData\\Local"),
});

const retroarch = emulatorById("retroarch")!;
const ppsspp = emulatorById("ppsspp")!;
const dolphin = emulatorById("dolphin")!;

describe("detectEmulator", () => {
	test("RetroArch on PATH, cores scanned + quoted exe token", () => {
		const d = detectEmulator(
			retroarch,
			env({
				which: { retroarch: "/usr/bin/retroarch" },
				dirs: {
					"/home/u/.config/retroarch/cores": [
						"snes9x_libretro.so",
						"mgba_libretro.so",
						"notes.txt",
					],
				},
			}),
		);
		expect(d?.via).toBe("path");
		expect(d?.exeToken).toBe("'/usr/bin/retroarch'");
		expect(d?.coresDir).toBe("/home/u/.config/retroarch/cores");
		expect(d?.cores).toEqual(["mgba", "snes9x"]);
	});

	test("RetroArch via Flatpak when not on PATH", () => {
		const d = detectEmulator(
			retroarch,
			env({
				flatpaks: ["org.libretro.RetroArch"],
				dirs: {
					"/home/u/.var/app/org.libretro.RetroArch/config/retroarch/cores": [
						"snes9x_libretro.so",
					],
				},
			}),
		);
		expect(d?.via).toBe("flatpak");
		expect(d?.exeToken).toBe("flatpak run org.libretro.RetroArch");
		expect(d?.appId).toBe("org.libretro.RetroArch");
		expect(d?.cores).toEqual(["snes9x"]);
	});

	test("Windows path with spaces is double-quoted", () => {
		const d = detectEmulator(
			ppsspp,
			env({
				os: "windows",
				files: ["C:\\Program Files\\PPSSPP\\PPSSPPWindows64.exe"],
			}),
		);
		expect(d?.via).toBe("file");
		expect(d?.exeToken).toBe(
			'"C:\\Program Files\\PPSSPP\\PPSSPPWindows64.exe"',
		);
	});

	test("returns null when not installed", () => {
		expect(detectEmulator(dolphin, env({}))).toBeNull();
	});
});