import { mkdtempSync, readdirSync, readFileSync, rmSync } from "node:fs";
import { tmpdir } from "node:os";
import { join } from "node:path";
import { afterEach, describe, expect, it, vi } from "vitest";
import { createTestSession, type TestSession } from "../../../test/harness";
import nuBangExtension from "../index";

describe("nu-bang pi-test-harness", () => {
	let t: TestSession | undefined;

	afterEach(() => {
		t?.dispose();
		t = undefined;
	});

	it("writes enabled lifecycle debug records in an isolated sandbox", async () => {
		const root = mkdtempSync(join(tmpdir(), "pi-ext-nu-bang-debug-"));
		const original = {
			debug: process.env.PI_NU_BANG_DEBUG,
			state: process.env.XDG_STATE_HOME,
		};
		try {
			process.env.PI_NU_BANG_DEBUG = "1";
			process.env.XDG_STATE_HOME = join(root, "state");
			vi.resetModules();
			const { default: extension } = await import("../index.ts");
			t = await createTestSession({
				cwd: root,
				env: {
					PI_NU_BANG_DEBUG: "1",
					XDG_STATE_HOME: join(root, "state"),
				},
				extensionFactories: [extension],
			});
			await t.session.extensionRunner.emit({
				type: "session_start",
				reason: "startup",
			});
			await t.session.extensionRunner.emit({
				type: "session_shutdown",
				reason: "quit",
			});
			const events = readdirSync(
				join(root, "state", "pi-ext", "debug", "nu-bang"),
			).flatMap((file) =>
				readFileSync(
					join(root, "state", "pi-ext", "debug", "nu-bang", file),
					"utf8",
				)
					.trim()
					.split("\n")
					.map((line) => JSON.parse(line)),
			);
			expect(events).toEqual(
				expect.arrayContaining([
					expect.objectContaining({
						extension: "nu-bang",
						event: "session.start",
					}),
					expect.objectContaining({
						extension: "nu-bang",
						event: "session.shutdown",
					}),
				]),
			);
		} finally {
			t?.dispose();
			t = undefined;
			if (original.debug === undefined) delete process.env.PI_NU_BANG_DEBUG;
			else process.env.PI_NU_BANG_DEBUG = original.debug;
			if (original.state === undefined) delete process.env.XDG_STATE_HOME;
			else process.env.XDG_STATE_HOME = original.state;
			rmSync(root, { recursive: true, force: true });
		}
	});

	it("loads in real Pi extension runtime", async () => {
		t = await createTestSession({ extensionFactories: [nuBangExtension] });

		expect(t.session.extensionRunner.extensions).toHaveLength(1);
	});
});