import { afterEach, beforeEach, describe, expect, it, vi } from "bun:test";
import { JsRuntime, type RuntimeHooks } from "../../src/eval/js/shared/runtime";
import { bindBrowserRunFacade, waitForBrowserRun } from "../../src/tools/browser/run-cancellation";

describe("browser run cancellation", () => {
	beforeEach(() => {
		vi.useFakeTimers();
	});

	afterEach(() => {
		vi.useRealTimers();
	});

	it("aborts run-scoped wait() before a stale continuation can mutate the tab", async () => {
		const runtime = new JsRuntime({ initialCwd: process.cwd(), sessionId: "browser-run-cancellation-test" });
		const timeoutSignal = AbortSignal.timeout(20);
		const runAc = new AbortController();
		const signal = AbortSignal.any([timeoutSignal, runAc.signal]);
		const state: { lateNavigation?: string; displays: string[] } = { displays: [] };
		const { promise: cancelRejection, reject } = Promise.withResolvers<never>();
		const hooks: RuntimeHooks = {
			onText: chunk => state.displays.push(chunk),
			onDisplay: output => state.displays.push(JSON.stringify(output)),
			callTool: async () => undefined,
		};
		timeoutSignal.addEventListener("abort", () => reject(new Error("Browser code execution timed out after 20ms")), {
			once: true,
		});
		runtime.setRunScope({
			wait: (ms: number): Promise<void> => waitForBrowserRun(ms, signal),
			tab: bindBrowserRunFacade(
				{
					goto: async (url: string): Promise<void> => {
						state.lateNavigation = url;
					},
				},
				signal,
			),
		});

		const run = Promise.race([
			runtime.run(
				'try { await wait(60); } catch {} await tab.goto("https://late.example"); display("late display");',
				"browser-run-cancellation-test.js",
				hooks,
			),
			cancelRejection,
		]);
		vi.advanceTimersByTime(20);
		await expect(run).rejects.toThrow("Browser code execution timed out after 20ms");
		runAc.abort(new Error("Browser run ended"));
		vi.advanceTimersByTime(100);
		await Promise.resolve();
		await Promise.resolve();

		expect(state.lateNavigation).toBeUndefined();
		expect(state.displays).toEqual([]);
	});
});