import { join } from "jsr:@std/path";

const dir = import.meta.dirname!;

let deaths = 0;
const clients = new Set<WebSocket>();

// Load persisted count
try {
  const data = JSON.parse(await Deno.readTextFile("counter.json"));
  deaths = Number(data.count) || 0;
} catch {
  // No file yet — start at 0
}

function broadcast(payload: string) {
  for (const ws of clients) {
    if (ws.readyState === WebSocket.OPEN) ws.send(payload);
  }
}

async function persist() {
  await Deno.writeTextFile("counter.json", JSON.stringify({ count: deaths }));
}

function handleSocket(ws: WebSocket) {
  ws.onopen = () => {
    clients.add(ws);
    ws.send(JSON.stringify({ count: deaths }));
  };

  ws.onmessage = async (e) => {
    try {
      const msg = JSON.parse(e.data);
      const before = deaths;

      if (msg.action === "increment") deaths = Math.min(3999, deaths + 1);
      else if (msg.action === "decrement") deaths = Math.max(0, deaths - 1);
      else if (msg.action === "reset") deaths = 0;
      else return;

      if (deaths !== before) await persist();
      broadcast(JSON.stringify({ count: deaths }));
    } catch {
      // Ignore malformed messages
    }
  };

  ws.onclose = () => clients.delete(ws);
  ws.onerror = () => clients.delete(ws);
}

async function handler(req: Request): Promise<Response> {
  const url = new URL(req.url);

  if (url.pathname === "/ws") {
    const upgrade = req.headers.get("upgrade") ?? "";
    if (upgrade.toLowerCase() !== "websocket") {
      return new Response("WebSocket upgrade required", { status: 426 });
    }
    const { socket, response } = Deno.upgradeWebSocket(req);
    handleSocket(socket);
    return response;
  }

  if (url.pathname === "/mobile") {
    const html = await Deno.readTextFile(join(dir, "mobile.html"));
    return new Response(html, { headers: { "content-type": "text/html; charset=utf-8" } });
  }

  if (url.pathname === "/obs") {
    const html = await Deno.readTextFile(join(dir, "obs.html"));
    return new Response(html, { headers: { "content-type": "text/html; charset=utf-8" } });
  }

  // Default: desktop
  const html = await Deno.readTextFile(join(dir, "desktop.html"));
  return new Response(html, { headers: { "content-type": "text/html; charset=utf-8" } });
}

console.log("Elden Ring Counter running on http://localhost:8080");
console.log("Mobile: http://<your-local-ip>:8080/mobile");
console.log("Obs: http://<your-local-ip>:8080/obs");
Deno.serve({ port: 8080 }, handler);