import {
	createServer,
	type IncomingMessage,
	type ServerResponse,
} from "node:http";
import type { AddressInfo } from "node:net";

import { afterEach, describe, expect, it } from "vitest";
import { WebSocketServer } from "ws";

import { HttpClient } from "../../src/_shared/http.js";
import { WsConnection } from "../../src/_shared/websocket.js";
import { ConflictError, TimeoutError } from "../../src/exceptions.js";

interface CapturedRequest {
	method?: string;
	url?: string;
	headers: IncomingMessage["headers"];
	body: string;
}

function readRequestBody(request: IncomingMessage): Promise<string> {
	return new Promise((resolve, reject) => {
		let body = "";
		request.setEncoding("utf8");
		request.on("data", (chunk) => {
			body += chunk;
		});
		request.on("end", () => resolve(body));
		request.on("error", reject);
	});
}

function listen(server: ReturnType<typeof createServer>): Promise<number> {
	return new Promise((resolve) => {
		server.listen(0, "127.0.0.1", () => {
			const address = server.address() as AddressInfo;
			resolve(address.port);
		});
	});
}

function closeHttpServer(
	server: ReturnType<typeof createServer>,
): Promise<void> {
	return new Promise((resolve, reject) => {
		server.close((error) => {
			if (error) reject(error);
			else resolve();
		});
	});
}

function closeWebSocketServer(server: WebSocketServer): Promise<void> {
	return new Promise((resolve, reject) => {
		server.close((error) => {
			if (error) reject(error);
			else resolve();
		});
	});
}

describe("foundation integration", () => {
	const cleanup: Array<() => Promise<void>> = [];

	afterEach(async () => {
		await Promise.all(cleanup.splice(0).map((close) => close()));
	});

	it("sends JSON requests through a real HTTP server", async () => {
		let captured: CapturedRequest | undefined;
		const server = createServer(async (request, response: ServerResponse) => {
			captured = {
				method: request.method,
				url: request.url,
				headers: request.headers,
				body: await readRequestBody(request),
			};
			response.writeHead(200, { "Content-Type": "application/json" });
			response.end(JSON.stringify({ ok: true }));
		});
		const port = await listen(server);
		cleanup.push(() => closeHttpServer(server));

		const client = new HttpClient({
			baseUrl: `http://127.0.0.1:${port}`,
			apiKey: "api-key",
			token: "jwt-token",
			hostToken: "host-token",
		});

		await expect(
			client.post(
				"/v1/foundation",
				{ hello: "world" },
				{ params: { page: 1 } },
			),
		).resolves.toEqual({ ok: true });

		expect(captured).toMatchObject({
			method: "POST",
			url: "/v1/foundation?page=1",
			body: JSON.stringify({ hello: "world" }),
		});
		expect(captured?.headers["content-type"]).toBe("application/json");
		expect(captured?.headers.accept).toBe("application/json");
		expect(captured?.headers.authorization).toBe("Bearer jwt-token");
		expect(captured?.headers["x-api-key"]).toBe("api-key");
		expect(captured?.headers["x-host-token"]).toBe("host-token");
	});

	it("maps real HTTP error responses to SDK errors", async () => {
		const server = createServer((_request, response) => {
			response.writeHead(409, { "Content-Type": "application/json" });
			response.end(
				JSON.stringify({
					error: { code: "capsule_busy", message: "Capsule is busy" },
				}),
			);
		});
		const port = await listen(server);
		cleanup.push(() => closeHttpServer(server));

		const client = new HttpClient({ baseUrl: `http://127.0.0.1:${port}` });

		await expect(client.get("/v1/error")).rejects.toMatchObject({
			code: "capsule_busy",
			message: "Capsule is busy",
			statusCode: 409,
		});
		await expect(client.get("/v1/error")).rejects.toBeInstanceOf(ConflictError);
	});

	it("aborts real HTTP requests using timeoutMs", async () => {
		const server = createServer((_request, response) => {
			setTimeout(() => {
				response.writeHead(200, { "Content-Type": "application/json" });
				response.end(JSON.stringify({ ok: true }));
			}, 200);
		});
		const port = await listen(server);
		cleanup.push(() => closeHttpServer(server));

		const client = new HttpClient({ baseUrl: `http://127.0.0.1:${port}` });

		await expect(
			client.get("/v1/slow", { timeoutMs: 10 }),
		).rejects.toBeInstanceOf(TimeoutError);
	});

	it("exchanges JSON messages through a real WebSocket server", async () => {
		const server = new WebSocketServer({ port: 0, host: "127.0.0.1" });
		cleanup.push(() => closeWebSocketServer(server));

		const receivedByServer = new Promise<unknown>((resolve) => {
			server.on("connection", (socket, request) => {
				expect(request.headers["x-api-key"]).toBe("api-key");
				expect(request.headers["x-host-token"]).toBe("host-token");
				socket.on("message", (raw) => resolve(JSON.parse(raw.toString())));
				socket.send(JSON.stringify({ type: "ready" }));
			});
		});
		await new Promise<void>((resolve) => server.once("listening", resolve));
		const address = server.address() as AddressInfo;

		const messages: unknown[] = [];
		const connection = await WsConnection.connect({
			baseUrl: `http://127.0.0.1:${address.port}`,
			path: "/v1/ws",
			apiKey: "api-key",
			hostToken: "host-token",
			onMessage: (message) => messages.push(message),
		});

		connection.send({ type: "start" });

		await expect(receivedByServer).resolves.toEqual({ type: "start" });
		expect(messages).toEqual([{ type: "ready" }]);
		expect(connection.isClosed).toBe(false);

		connection.close();
	});
});