import type { Dump, OnlineUser } from "../model/interfaces.ts";

export interface WsClient {
  socket: WebSocket;
  userId?: string;
  username?: string;
  avatarMime?: string;
}

const clients = new Set<WsClient>();

export function register(client: WsClient): void {
  clients.add(client);
}

export function unregister(client: WsClient): void {
  clients.delete(client);
}

export function updateClientAvatar(userId: string, avatarMime: string): void {
  for (const client of clients) {
    if (client.userId === userId) {
      client.avatarMime = avatarMime;
    }
  }
  broadcastPresence();
}

export function getOnlineUsers(): OnlineUser[] {
  const seen = new Map<string, OnlineUser>();
  for (const client of clients) {
    if (client.userId && !seen.has(client.userId)) {
      seen.set(client.userId, {
        userId: client.userId,
        username: client.username!,
        hasAvatar: !!client.avatarMime,
      });
    }
  }
  return Array.from(seen.values());
}

function send(socket: WebSocket, data: unknown): void {
  if (socket.readyState === WebSocket.OPEN) {
    socket.send(JSON.stringify(data));
  }
}

export function broadcastPresence(): void {
  const users = getOnlineUsers();
  for (const client of clients) {
    send(client.socket, { type: "presence_update", users });
  }
}

export function broadcastNewDump(dump: Dump): void {
  for (const client of clients) {
    send(client.socket, { type: "dump_created", dump });
  }
}

export function broadcastDumpDeleted(dumpId: string): void {
  for (const client of clients) {
    send(client.socket, { type: "dump_deleted", dumpId });
  }
}

export function broadcastVoteUpdate(
  dumpId: string,
  voteCount: number,
  voterId: string,
  action: "cast" | "remove",
): void {
  for (const client of clients) {
    send(client.socket, {
      type: "votes_update",
      dumpId,
      voteCount,
      voterId,
      action,
    });
  }
}

// Keepalive: ping all clients every 30s, remove non-responsive ones
const PING_INTERVAL = 30_000;
const _PONG_TIMEOUT = 5_000;

setInterval(() => {
  for (const client of clients) {
    if (client.socket.readyState !== WebSocket.OPEN) {
      clients.delete(client);
      continue;
    }
    send(client.socket, { type: "ping" });
    // Schedule removal if no pong (tracked via heartbeat flag)
  }
}, PING_INTERVAL);