// Covers connect setup, validation, one-time redemption, rate limits, admin history, and secrecy.

import { Database } from "bun:sqlite";
import { afterAll, describe, expect, setSystemTime, test } from "bun:test";
import { mkdtemp } from "node:fs/promises";
import { tmpdir } from "node:os";
import { join } from "node:path";
import { createApp } from "../src/server/app.ts";
import { makeBackup } from "../src/server/backup.ts";
import { type Config, parseConfig } from "../src/server/config.ts";
import { openKeprDb } from "../src/server/db.ts";
import { Browser, PASSWORD } from "./browser.ts";

const ORIGIN = "https://kepr.example";
const WRITE = { accessKeyId: "WRITE-ID", secretAccessKey: "WRITE-SECRET" };
// One argon2 hash for the whole file: every instance shares it, so the suite stays quick.
const HASH = await Bun.password.hash(PASSWORD, "argon2id");
let clock = Date.parse("2026-09-27T12:00:00Z");
setSystemTime(clock);
afterAll(() => setSystemTime());

async function build(write = true, folder = false) {
	const dataDir = await mkdtemp(join(tmpdir(), "kepr-connect-"));
	const kepr = openKeprDb(dataDir);
	const bucket: Config["bucket"] = folder
		? { kind: "folder", path: dataDir }
		: {
				kind: "s3",
				endpoint: "https://s3.fr-par.scw.cloud",
				name: "my-bucket",
				region: "fr-par",
				accessKeyId: "read-id",
				secretAccessKey: "read-secret",
				...(write ? { write: WRITE } : {}),
			};
	const config: Config = {
		domain: "kepr.example",
		dataDir,
		adminPasswordHash: HASH,
		bucket,
	};
	return { app: createApp(config, kepr), kepr, config };
}

async function connected(write = true) {
	const built = await build(write);
	const browser = new Browser(built.app, `198.51.100.${Math.floor(Math.random() * 200) + 1}`);
	await browser.signIn();
	return { ...built, browser };
}

async function issue(browser: Browser, machine = "laptop") {
	await browser.get(`/connect?machine=${encodeURIComponent(machine)}`);
	const page = await browser.post("/connect", { machine });
	const body = await page.text();
	const match = /class="mono code">([^<]+)/.exec(body);
	const code = match?.[1]?.trim() ?? "";
	if (code === "") {
		// A page without a code is the interesting failure: say what it said instead.
		throw new Error(`no code on the connect page (${page.status}): ${body.slice(0, 300)}`);
	}
	return { page, body, code };
}

async function redeem(app: ReturnType<typeof createApp>, code: string, address = "203.0.113.77") {
	const browser = new Browser(app, address);
	return browser.post("/api/connect", { code });
}

describe.serial("connect configuration and page", () => {
	test("parseConfig rejects write keys beside a folder bucket and empty write values", () => {
		const hash = "$argon2id$v=19$m=65536,t=2,p=1$abc$abc";
		expect(() =>
			parseConfig(
				`domain = "kepr.example"\nadmin_password_hash = "${hash}"\n[bucket]\nfolder = "/tmp/x"\n[bucket.write]\naccess_key_id = "x"\nsecret_access_key = "y"`,
			),
		).toThrow();
		expect(() =>
			parseConfig(
				`domain = "kepr.example"\nadmin_password_hash = "${hash}"\n[bucket]\nendpoint = "https://x"\nname = "n"\nregion = "r"\naccess_key_id = "a"\nsecret_access_key = "s"\n[bucket.write]\naccess_key_id = ""\nsecret_access_key = "y"`,
			),
		).toThrow();
	});

	test("folder buckets and S3 buckets without write keys hide all connect routes", async () => {
		for (const built of [await build(false), await build(false, true)]) {
			const browser = new Browser(built.app);
			expect((await browser.get("/connect?machine=x")).status).toBe(404);
			expect((await browser.post("/connect", { machine: "x" })).status).toBe(404);
			expect((await browser.post("/api/connect", { code: "ABCDEFGH" })).status).toBe(404);
		}
	});

	test("a disabled connect route is an unknown path, byte for byte", async () => {
		const { app } = await build(false);
		const browser = new Browser(app);
		for (const [method, path] of [
			["GET", "/connect?machine=x"],
			["POST", "/connect"],
			["POST", "/api/connect"],
		] as const) {
			const asked = method === "GET" ? browser.get(path) : browser.post(path, {});
			const unknown =
				method === "GET" ? browser.get("/nothing/here") : browser.post("/nothing/here", {});
			const [found, absent] = await Promise.all([asked, unknown]);
			expect(`${found.status} ${await found.text()}`).toBe(
				`${absent.status} ${await absent.text()}`,
			);
			expect(found.headers.get("cache-control")).toBe(absent.headers.get("cache-control"));
		}
		// Even an oversized body is answered here the way the unknown path answers it.
		const big = { code: "x".repeat(70_000) };
		const oversized = await browser.post("/api/connect", big);
		const unrouted = await browser.post("/nothing/here", big);
		expect(`${oversized.status} ${await oversized.text()}`).toBe(
			`${unrouted.status} ${await unrouted.text()}`,
		);
		expect(oversized.headers.get("cache-control")).toBe(unrouted.headers.get("cache-control"));
	});

	test("a signed-out request redirects before the machine name is judged", async () => {
		const { app } = await build();
		const browser = new Browser(app);
		const response = await browser.get(`/connect?machine=${encodeURIComponent("x".repeat(65))}`);
		expect(response.status).toBe(302);
		expect(response.headers.get("location")).toBe("/sign-in?next=%2Fconnect");
	});

	test("connect redirects signed out, preserves next, and rejects unsafe next values", async () => {
		const built = await build();
		const browser = new Browser(built.app);
		const response = await browser.get("/connect?machine=desk%20%26%20rack");
		expect(response.status).toBe(302);
		for (const next of ["https://evil.example", "//evil.example", "/bad\n"]) {
			const sign = await browser.get(`/sign-in?next=${encodeURIComponent(next)}`);
			const html = await sign.text();
			expect(html).toContain('name="next" value="/admin"');
		}
		const sign = await browser.get("/sign-in?next=%2Fconnect%3Fmachine%3Ddesk");
		const form = /name="form" value="([^"]+)"/.exec(await sign.text())?.[1] ?? "";
		const wrong = await browser.request("/sign-in", {
			method: "POST",
			headers: { origin: ORIGIN },
			body: new URLSearchParams({ form, next: "/connect?machine=desk", password: "wrong" }),
		});
		expect(wrong.status).toBe(401);
		expect(await wrong.text()).toContain('name="next" value="/connect?machine=desk"');
		const good = await browser.request("/sign-in", {
			method: "POST",
			headers: { origin: ORIGIN },
			body: new URLSearchParams({ form, next: "/connect?machine=desk", password: PASSWORD }),
		});
		expect(good.status).toBe(303);
		expect(good.headers.get("location")).toBe("/connect?machine=desk");
	});

	test("connect validates and escapes machine names, and never caches or exposes secrets", async () => {
		const { browser } = await connected();
		for (const machine of ["", "x".repeat(65), "bad\nname", "bad\u0085name", "bad\u202ename"])
			expect((await browser.get(`/connect?machine=${encodeURIComponent(machine)}`)).status).toBe(
				400,
			);
		const result = await issue(browser, "<img src=x onerror=alert(1)>");
		expect(result.page.status).toBe(200);
		expect(result.body).toContain("&lt;img src=x onerror=alert(1)&gt;");
		expect(result.body).not.toContain("WRITE-SECRET");
		expect(result.page.headers.get("cache-control")).toBe("no-store");
	});
});

describe.serial("connect redemption", () => {
	test("stores only a hash, redeems once with exact credentials, normalizes code, and gives identical failures", async () => {
		const { app, browser, kepr, config } = await connected();
		const { code, body } = await issue(browser, "office");
		expect(code).toMatch(/^[A-Z2-9]{4}-[A-Z2-9]{4}$/);
		expect(body).not.toContain("WRITE-SECRET");
		const row = kepr.query("SELECT code_hash, machine FROM connect_codes").get() as {
			code_hash: string;
			machine: string;
		};
		expect(row.code_hash).toMatch(/^[0-9a-f]{64}$/);
		expect(row.code_hash).not.toContain(code.replace("-", ""));
		expect(row.machine).toBe("office");
		const success = await redeem(app, code.toLowerCase(), "203.0.113.88");
		expect(success.status).toBe(200);
		expect(await success.json()).toEqual({
			endpoint: config.bucket.kind === "s3" ? config.bucket.endpoint : "",
			bucket: "my-bucket",
			region: "fr-par",
			access_key_id: "WRITE-ID",
			secret_access_key: "WRITE-SECRET",
		});
		expect(success.headers.get("cache-control")).toBe("no-store");
		const used = await redeem(app, code, "203.0.113.89");
		const unknown = await redeem(app, "ZZZZ-ZZZZ", "203.0.113.90");
		expect(used.status).toBe(404);
		expect(await used.text()).toBe(await unknown.text());
		expect(used.headers.get("cache-control")).toBe("no-store");
	});

	test("connect POST requires session, origin and fresh form token", async () => {
		const built = await build();
		const browser = new Browser(built.app);
		expect((await browser.post("/connect", { machine: "x" })).status).toBe(401);
		await browser.signIn();
		expect((await browser.post("/connect", { machine: "x" }, "https://evil.example")).status).toBe(
			403,
		);
		expect((await browser.post("/connect", { machine: "x", form: "stale" })).status).toBe(403);
	});

	test("expired, malformed and missing codes all return the same no-code response", async () => {
		const { app, browser } = await connected();
		const { code } = await issue(browser);
		clock += 601_000;
		setSystemTime(clock);
		const expired = await redeem(app, code, "198.51.100.201");
		const malformed = await redeem(app, "bad", "198.51.100.202");
		const missing = await new Browser(app, "198.51.100.203").request("/api/connect", {
			method: "POST",
			body: "not-a-form",
		});
		expect(expired.status).toBe(404);
		const expected = await expired.text();
		expect(expected).toBe('{"error":"no_code","message":"no code"}');
		expect(await malformed.text()).toBe(expected);
		expect(await missing.text()).toBe(expected);
	});

	test("rate limits ten attempts per peer while another peer succeeds", async () => {
		const { app, browser } = await connected();
		const { code } = await issue(browser);
		for (let i = 0; i < 10; i++) await redeem(app, "bad", "192.0.2.40");
		const limited = await redeem(app, code, "192.0.2.40");
		expect(limited.status).toBe(404);
		const other = await redeem(app, code, "192.0.2.41");
		expect(other.status).toBe(200);
		// The window is an hour: once it has passed the same peer is served again.
		clock += 3_601_000;
		setSystemTime(clock);
		const { code: fresh } = await issue(browser, "later");
		expect((await redeem(app, fresh, "192.0.2.40")).status).toBe(200);
	});

	test("the attempt window is counted by time, not by the list's order", async () => {
		const { app, browser } = await connected();
		const address = "192.0.2.70";
		// Nine attempts at one moment...
		for (let i = 0; i < 9; i++) await redeem(app, "bad", address);
		// ...then the clock steps back — an NTP correction, or a test's fake timer — and a tenth
		// attempt lands *older* than the nine before it. A prune that walks the list by position
		// stops at the first entry still inside the window and never reaches that one.
		clock -= 120_000;
		setSystemTime(clock);
		await redeem(app, "bad", address);
		// Now: an hour and two minutes after the nine, so the older tenth has left the window while
		// they are still inside it — the peer has one attempt left, not none.
		clock += 3_620_000;
		setSystemTime(clock);
		const { code } = await issue(browser, "after the step");
		expect((await redeem(app, code, address)).status).toBe(200);
	});

	test("refused attempts are not recorded, so hammering neither grows the list nor the block", async () => {
		const { app, browser } = await connected();
		const address = "192.0.2.90";
		for (let i = 0; i < 10; i++) await redeem(app, "bad", address);
		// Fifty more inside the hour are all refused, and none of them is remembered: kept, they would
		// cost memory per request and move the block out an hour past the last one.
		clock += 3_540_000;
		setSystemTime(clock);
		for (let i = 0; i < 50; i++) expect((await redeem(app, "bad", address)).status).toBe(404);
		// An hour after the tenth counted attempt the peer is served again.
		clock += 61_000;
		setSystemTime(clock);
		const { code } = await issue(browser, "after the block");
		expect((await redeem(app, code, address)).status).toBe(200);
	});

	test("a forged X-Forwarded-For does not buy another bucketful", async () => {
		const { app, browser } = await connected();
		const { code } = await issue(browser);
		for (let i = 0; i < 10; i++) await redeem(app, "bad", "192.0.2.50");
		const forged = await new Browser(app, "192.0.2.50").request("/api/connect", {
			method: "POST",
			headers: {
				"x-forwarded-for": "198.51.100.99",
				"content-type": "application/x-www-form-urlencoded",
			},
			body: new URLSearchParams({ code }),
		});
		expect(forged.status).toBe(404);
	});

	test("two redemptions at once: exactly one wins", async () => {
		const { app, browser } = await connected();
		const { code } = await issue(browser, "race");
		const [first, second] = await Promise.all([
			redeem(app, code, "203.0.113.101"),
			redeem(app, code, "203.0.113.102"),
		]);
		expect([first.status, second.status].sort()).toEqual([200, 404]);
	});

	test("an oversized redemption is refused with the same no-code body", async () => {
		const { app } = await connected();
		const response = await new Browser(app, "192.0.2.60").post("/api/connect", {
			code: "x".repeat(70_000),
		});
		expect(response.status).toBe(404);
		expect(await response.text()).toBe('{"error":"no_code","message":"no code"}');
		expect(response.headers.get("cache-control")).toBe("no-store");
	});

	test("a backup carries the hashed code and never the write key", async () => {
		const { browser, kepr, config } = await connected();
		const { code } = await issue(browser, "laptop");
		const name = makeBackup(kepr, config.dataDir);
		const file = join(config.dataDir, "backups", name, "kepr.db");
		const copy = new Database(file, { readonly: true });
		const rows = copy.query("SELECT machine, code_hash FROM connect_codes").all();
		copy.close();
		expect(rows.length).toBe(1);
		expect(JSON.stringify(rows)).not.toContain(code.replace("-", ""));
		// The write key is read from kepr.toml alone, so no copy of kepr.db can hold it.
		const bytes = await Bun.file(file).bytes();
		expect(new TextDecoder().decode(bytes)).not.toContain("WRITE-SECRET");
	});
});

describe.serial("connected machines in admin", () => {
	test("lists redeemed machines newest first, at most twenty, with revocation guidance", async () => {
		const { app, browser, kepr } = await connected();
		for (let i = 0; i < 22; i++) {
			const { code } = await issue(browser, `machine-${i}`);
			const response = await redeem(app, code, `10.0.0.${i + 1}`);
			expect(response.status).toBe(200);
			clock += 1000;
			setSystemTime(clock);
		}
		const admin = await browser.get("/admin");
		const html = await admin.text();
		expect(html).toContain("Machines connected");
		expect(html).toContain("rotate the write key in Scaleway");
		expect(html).not.toContain("machine-0 ");
		expect(html).toContain("machine-21");
		expect(html.indexOf("machine-21")).toBeLessThan(html.indexOf("machine-20"));
		// Only what the list can show is kept: the two oldest redemptions are gone from kepr.db.
		const kept = kepr
			.query<{ machine: string }, []>(
				"SELECT machine FROM connect_codes WHERE used_at IS NOT NULL ORDER BY used_at",
			)
			.all();
		expect(kept.length).toBe(20);
		expect(kept[0]?.machine).toBe("machine-2");
	});

	test("redemptions in one second keep and list the latest twenty", async () => {
		const { app, browser, kepr } = await connected();
		for (let i = 0; i < 22; i++) {
			const { code } = await issue(browser, `machine-${i}`);
			expect((await redeem(app, code, `10.0.1.${i + 1}`)).status).toBe(200);
		}
		const html = await (await browser.get("/admin")).text();
		expect(html).not.toContain("machine-1 ");
		expect(html.indexOf("machine-21")).toBeLessThan(html.indexOf("machine-2 "));
		const kept = kepr
			.query<{ machine: string }, []>("SELECT machine FROM connect_codes WHERE used_at IS NOT NULL")
			.all()
			.map((row) => row.machine);
		expect(kept).not.toContain("machine-0");
		expect(kept).not.toContain("machine-1");
		expect(kept.length).toBe(20);
	});
});