import { readdirSync, readFileSync } from "node:fs";
import path from "node:path";
import { afterEach, describe, expect, it } from "vitest";
import { createTestSession, type TestSession } from "../../../test/harness";

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

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

	it("loads in real Pi extension runtime", async () => {
		const extensionPath = path.resolve(import.meta.dirname, "../index.ts");
		t = await createTestSession({ extensions: [extensionPath] });

		expect(t.session.extensionRunner.extensions).toHaveLength(1);
		expect(t.session.extensionRunner.extensions[0].path).toBe(extensionPath);
	});

	it("writes debug lifecycle records in its sandbox when enabled", async () => {
		const extensionPath = path.resolve(import.meta.dirname, "../index.ts");
		t = await createTestSession({
			env: { PI_TPS_DEBUG: "1" },
			extensions: [extensionPath],
		});
		const extension = t.session.extensionRunner.extensions[0];
		const context = t.session.extensionRunner.createCommandContext();
		for (const handler of extension.handlers.get("session_start"))
			await handler({ type: "session_start" }, context);
		for (const handler of extension.handlers.get("agent_start"))
			await handler({ type: "agent_start" }, context);
		for (const handler of extension.handlers.get("agent_end"))
			await handler({ type: "agent_end", messages: [] }, context);
		for (const handler of extension.handlers.get("session_shutdown"))
			await handler({ type: "session_shutdown" }, context);
		const directory = path.join(t.cwd, ".test-state", "pi-ext", "debug", "tps");
		const records = readFileSync(
			path.join(directory, readdirSync(directory)[0]),
			"utf8",
		)
			.trim()
			.split("\n")
			.map((line) => JSON.parse(line));
		expect(records).toEqual(
			expect.arrayContaining([
				expect.objectContaining({ event: "session.start" }),
				expect.objectContaining({ event: "session.shutdown" }),
				expect.objectContaining({ event: "rate.finish", outcome: "idle" }),
			]),
		);
	});
});