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

const extensionPath = path.resolve(import.meta.dirname, "../index.ts");
const ENV = "PI_SESSION_RENAME_IDLE_DELAY_MS";

type Case = {
	user?: unknown;
	project?: unknown;
	env?: string;
	untrusted?: boolean;
};

describe("session-rename.idleDelayMs resolution", () => {
	let t: TestSession | undefined;
	let root: string | undefined;
	afterEach(async () => {
		await t?.session.extensionRunner.emit({
			type: "session_shutdown",
			reason: "quit",
		});
		t?.dispose();
		t = undefined;
		vi.restoreAllMocks();
		if (root) rmSync(root, { recursive: true, force: true });
		root = undefined;
	});

	async function start(input: Case) {
		root = mkdtempSync(path.join(tmpdir(), "pi-ext-session-rename-settings-"));
		const write = (dir: string, value: unknown) => {
			mkdirSync(dir, { recursive: true });
			writeFileSync(
				path.join(dir, "settings.json"),
				JSON.stringify({ "session-rename": { idleDelayMs: value } }),
			);
		};
		if ("user" in input)
			write(path.join(root, ".test-home/.pi/agent"), input.user);
		if ("project" in input) write(path.join(root, ".pi"), input.project);
		t = await createTestSession({
			cwd: root,
			extensions: [extensionPath],
			env: { [ENV]: input.env },
		});
		if (input.untrusted) t.session.settingsManager.setProjectTrusted(false);
		const runner = t.session.extensionRunner;
		// scheduleRename needs a session file; the harness session is in-memory.
		vi.spyOn(t.session.sessionManager, "getSessionFile").mockReturnValue(
			path.join(root, "session.jsonl"),
		);
		const notify = t.events.uiCallsFor("notify").length;
		await runner.emit({ type: "session_start", reason: "startup" });
		const warnings = t.events
			.uiCallsFor("notify")
			.slice(notify)
			.filter((call) => call.args[1] === "warning")
			.map((call) => call.args[0]);
		const setTimeoutSpy = vi.spyOn(globalThis, "setTimeout");
		await runner.emit({
			type: "turn_end",
			turnIndex: 0,
			message: { role: "assistant", content: [] },
			toolResults: [],
		} as never);
		const delays = setTimeoutSpy.mock.calls.map((call) => call[1]);
		setTimeoutSpy.mockRestore();
		return { delays, warnings };
	}

	it.each([
		["default unchanged", {}, 10_000],
		["user value", { user: 2_500 }, 2_500],
		["zero allowed", { user: 0 }, 0],
		["env over settings", { user: 2_500, project: 3_000, env: "4000" }, 4_000],
		["trusted project over user", { user: 2_500, project: 3_000 }, 3_000],
		[
			"untrusted project ignored",
			{ user: 2_500, project: 3_000, untrusted: true },
			2_500,
		],
	] satisfies [string, Case, number][])(
		"%s",
		async (_name, input, expected) => {
			const { delays, warnings } = await start(input);
			expect(delays).toContain(expected);
			expect(warnings).toEqual([]);
		},
	);

	it.each([
		[
			"string project",
			{ user: 2_500, project: "3000" },
			"Invalid session-rename.idleDelayMs from project settings",
		],
		[
			"negative user",
			{ user: -1 },
			"Invalid session-rename.idleDelayMs from user settings: expected an integer from 0 to 2147483647",
		],
		[
			"fractional project",
			{ user: 2_500, project: 1.5 },
			"Invalid session-rename.idleDelayMs from project settings: expected an integer from 0 to 2147483647",
		],
		[
			"non-numeric env",
			{ user: 2_500, env: "soon" },
			`Invalid session-rename.idleDelayMs from environment variable ${ENV}`,
		],
	] satisfies [string, Case, string][])(
		"rejects %s without falling through",
		async (_name, input, error) => {
			const { delays, warnings } = await start(input);
			expect(delays).toContain(10_000);
			expect(delays).not.toContain(2_500);
			expect(warnings).toEqual([`${error}; using 10000 ms`]);
		},
	);
});