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 CREDENTIALS = {
	PI_BAK_S3_ACCESS_KEY_ID: "id",
	PI_BAK_S3_SECRET_ACCESS_KEY: "secret",
};

const INIT_WARNING = "warning: bak: run /bak init <alias>";
const settingWarnings = (notes: string[]) =>
	notes.filter((note) => note.startsWith("warning") && note !== INIT_WARNING);

type Case = {
	user?: unknown;
	project?: unknown;
	untrusted?: boolean;
	env?: Record<string, string>;
};

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

	async function start(input: Case) {
		root = mkdtempSync(path.join(tmpdir(), "pi-ext-bak-settings-"));
		const write = (dir: string, bak: unknown) => {
			mkdirSync(dir, { recursive: true });
			writeFileSync(path.join(dir, "settings.json"), JSON.stringify({ bak }));
		};
		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);
		const requests: Request[] = [];
		vi.stubGlobal(
			"fetch",
			vi.fn(async (request: Request) => {
				requests.push(request);
				return new Response(null, { status: 404 });
			}),
		);
		t = await createTestSession({
			cwd: root,
			extensions: [extensionPath],
			env: { ...CREDENTIALS, ...input.env },
		});
		if (input.untrusted) t.session.settingsManager.setProjectTrusted(false);
		const runner = t.session.extensionRunner;
		// The harness already emitted one session_start; dedupe its notes.
		await runner.emit({ type: "session_start", reason: "startup" });
		const ctx = runner.createContext();
		const notes = () => [
			...new Set(
				t?.events
					.uiCallsFor("notify")
					.map((call) => `${call.args[1]}: ${call.args[0]}`),
			),
		];
		const bak = runner.extensions[0]?.commands.get("bak");
		if (!bak) throw new Error("missing bak command");
		return {
			notes,
			run: (args: string) => bak.handler(args, ctx),
			settle: async () => {
				await runner.emit({ type: "agent_settled" });
				await new Promise((resolve) => setTimeout(resolve, 50));
			},
			target: () => {
				const request = requests[0];
				if (!request) return undefined;
				const region = /Credential=id\/\d+\/([^/]+)\//.exec(
					request.headers.get("authorization") ?? "",
				)?.[1];
				return `${new URL(request.url).origin}${new URL(request.url).pathname.split("/").slice(0, 2).join("/")} ${region}`;
			},
		};
	}

	it("keeps missing-endpoint default", async () => {
		const { notes } = await start({});
		expect(notes()).toEqual([
			"warning: bak: disabled; missing PI_BAK_S3_ENDPOINT",
		]);
	});

	it.each([
		[
			"env only with defaults",
			{ env: { PI_BAK_S3_ENDPOINT: "https://env.test" } },
			"https://env.test/pi-bak auto",
		],
		[
			"user settings",
			{
				user: {
					s3: {
						endpoint: "https://user.test",
						bucket: "user-bucket",
						region: "eu",
					},
				},
			},
			"https://user.test/user-bucket eu",
		],
		[
			"env over settings",
			{
				user: { s3: { endpoint: "https://user.test", bucket: "user-bucket" } },
				env: {
					PI_BAK_S3_ENDPOINT: "https://env.test",
					PI_BAK_S3_BUCKET: "env-bucket",
					PI_BAK_S3_REGION: "us",
				},
			},
			"https://env.test/env-bucket us",
		],
		[
			"trusted project merged over user",
			{
				user: { s3: { endpoint: "https://user.test", region: "eu" } },
				project: { s3: { bucket: "project-bucket" } },
			},
			"https://user.test/project-bucket eu",
		],
		[
			"untrusted project ignored",
			{
				user: { s3: { endpoint: "https://user.test" } },
				project: { s3: { endpoint: "https://project.test" } },
				untrusted: true,
			},
			"https://user.test/pi-bak auto",
		],
	] satisfies [string, Case, string][])(
		"applies %s",
		async (_name, input, expected) => {
			const { notes, run, target } = await start(input);
			await run("refresh");
			expect(target()).toBe(expected);
			expect(settingWarnings(notes())).toEqual([]);
		},
	);

	it.each([
		[
			"non-string user bucket",
			{
				user: { s3: { endpoint: "https://user.test", bucket: 7 } },
				env: {},
			},
			"Invalid bak.s3.bucket from user settings: expected a non-empty string",
			"https://user.test/pi-bak auto",
		],
		[
			"empty env region over valid user region",
			{
				user: { s3: { endpoint: "https://user.test", region: "eu" } },
				env: { PI_BAK_S3_REGION: " " },
			},
			"Invalid bak.s3.region from environment variable PI_BAK_S3_REGION: expected a non-empty string",
			"https://user.test/pi-bak auto",
		],
		[
			"empty project bucket over valid user bucket",
			{
				user: { s3: { endpoint: "https://user.test", bucket: "user-bucket" } },
				project: { s3: { bucket: "" } },
			},
			"Invalid bak.s3.bucket from project settings: expected a non-empty string",
			"https://user.test/pi-bak auto",
		],
	] satisfies [string, Case, string, string][])(
		"rejects %s without falling through",
		async (_name, input, error, expected) => {
			const { notes, run, target } = await start(input);
			await run("refresh");
			expect(target()).toBe(expected);
			expect(settingWarnings(notes())).toEqual([
				`warning: bak: ${error}; using default`,
			]);
		},
	);

	it("rejects invalid endpoint and stays disabled", async () => {
		const { notes } = await start({
			user: { s3: { endpoint: "https://user.test" } },
			env: { PI_BAK_S3_ENDPOINT: "" },
		});
		expect(notes()).toEqual([
			"warning: bak: Invalid bak.s3.endpoint from environment variable PI_BAK_S3_ENDPOINT: expected a non-empty string; using default",
			"warning: bak: disabled; missing PI_BAK_S3_ENDPOINT",
		]);
	});

	const configured = { s3: { endpoint: "https://user.test" } };

	it.each([
		["default on", { user: configured }, true],
		["user false", { user: { ...configured, autoBackup: false } }, false],
		[
			"env over user",
			{
				user: { ...configured, autoBackup: false },
				env: { PI_BAK_AUTO_BACKUP: "1" },
			},
			true,
		],
		[
			"trusted project over user",
			{ user: configured, project: { autoBackup: false } },
			false,
		],
		[
			"untrusted project ignored",
			{ user: configured, project: { autoBackup: false }, untrusted: true },
			true,
		],
	] satisfies [string, Case, boolean][])(
		"autoBackup %s",
		async (_name, input, automatic) => {
			const { notes, settle } = await start(input);
			await settle();
			expect(notes()).toEqual(automatic ? [INIT_WARNING] : []);
		},
	);

	it.each([
		[
			"string user",
			{ user: { ...configured, autoBackup: "false" } },
			"Invalid bak.autoBackup from user settings",
		],
		[
			"non-boolean env",
			{
				user: { ...configured, autoBackup: false },
				env: { PI_BAK_AUTO_BACKUP: "off" },
			},
			"Invalid bak.autoBackup from environment variable PI_BAK_AUTO_BACKUP",
		],
	] satisfies [string, Case, string][])(
		"autoBackup rejects %s and keeps default on",
		async (_name, input, error) => {
			const { notes, settle } = await start(input);
			await settle();
			expect(notes()).toEqual([
				`warning: bak: ${error}; using default`,
				INIT_WARNING,
			]);
		},
	);

	it("keeps explicit backup when autoBackup is off", async () => {
		const { notes, run, settle } = await start({
			user: { ...configured, autoBackup: false },
		});
		await settle();
		expect(notes()).toEqual([]);
		await run("backup");
		expect(notes()).toContain("info: bak: backed up 0; 0 indexed");
	});
});