import { defineConnector, raw, type NormalizedBatch } from "@market-atlas/connector-sdk";
import type { NormalizedObservation } from "@market-atlas/market-model";
import { pairObservations, planPair } from "../_shared/pairs.js";

const WS_URL = "wss://ws.bitstamp.net";
/** Bitstamp url_symbol → [base, quote]. Includes the two real fiat markets (EUR/USD, GBP/USD). */
const PAIRS: Record<string, [string, string]> = {
  btcusd: ["BTC", "USD"],
  ethusd: ["ETH", "USD"],
  xrpusd: ["XRP", "USD"],
  ltcusd: ["LTC", "USD"],
  solusd: ["SOL", "USD"],
  adausd: ["ADA", "USD"],
  linkusd: ["LINK", "USD"],
  dogeusd: ["DOGE", "USD"],
  btceur: ["BTC", "EUR"],
  etheur: ["ETH", "EUR"],
  btcusdt: ["BTC", "USDT"],
  eurusd: ["EUR", "USD"],
  gbpusd: ["GBP", "USD"],
};

/** Bitstamp public WebSocket v2: live trades (price) + top of the order book (bid/ask) per pair. */
export const bitstampWs = defineConnector({
  metadata: {
    id: "bitstamp-ws",
    name: "Bitstamp — live trades & order book",
    version: "1.0.0",
    sourceId: "bitstamp",
    organization: "Bitstamp Ltd",
    sourceType: "WEBSOCKET",
    jurisdiction: "GB",
    rightsStatus: "PUBLIC_ATTRIBUTED",
    realtimeStatus: "REALTIME",
    expectedLatencyMs: 300,
    supportsStreaming: true,
    supportsHistorical: false,
    assetClasses: ["CRYPTO", "FOREX"],
    exchanges: ["bitstamp"],
    homepage: "https://www.bitstamp.net/websocket/v2/",
    description: "Public Bitstamp WebSocket v2: `live_trades_<pair>` (last trade, exchange microtimestamp) and `order_book_<pair>` (best bid/ask) for the major USD/EUR crypto markets and Bitstamp's fiat markets EUR/USD and GBP/USD.",
    rightsNotes: "Public market data displayed with attribution to Bitstamp.",
    termsUrl: "https://www.bitstamp.net/terms-of-use/",
    sourceFamily: "bitstamp",
    enabled: true,
  },
  seeds: Object.entries(PAIRS).map(([sym, [b, q]]) => ({ symbol: sym, hint: planPair(b, q, "bitstamp").hint, aliases: [`${b}-${q}`, `${b}/${q}`] })),
  defaultSymbols: Object.keys(PAIRS),
  async start(ctx) {
    const ws = ctx.openWebSocket(WS_URL, {
      label: "bitstamp",
      staleAfterMs: 120_000,
      heartbeat: { intervalMs: 25_000, message: JSON.stringify({ event: "bts:heartbeat" }) },
      onOpen: (sock) => {
        for (const p of ctx.watchedSymbols()) {
          sock.send({ event: "bts:subscribe", data: { channel: `live_trades_${p}` } });
          sock.send({ event: "bts:subscribe", data: { channel: `order_book_${p}` } });
        }
      },
      onMessage: (data) => {
        let msg: any;
        try {
          msg = JSON.parse(data);
        } catch {
          return;
        }
        if (msg?.event === "trade") ctx.emit(raw("bitstamp-ws", "bitstamp", "trade", msg));
        else if (msg?.event === "data" && typeof msg.channel === "string" && msg.channel.startsWith("order_book_")) ctx.emit(raw("bitstamp-ws", "bitstamp", "book", msg));
        else if (msg?.event === "bts:request_reconnect") ctx.logger.info("bitstamp asked to reconnect");
      },
    });
    ws.connect();
  },
  normalize(r): NormalizedBatch {
    const m = r.payload as { channel?: string; data?: Record<string, unknown> };
    const pairKey = typeof m.channel === "string" ? m.channel.replace(/^(live_trades_|order_book_)/, "") : "";
    const pair = PAIRS[pairKey];
    if (!pair || !m.data) return { observations: [] };
    const [base, quote] = pair;
    const micro = m.data.microtimestamp;
    const ts = typeof micro === "string" && /^\d+$/.test(micro) ? Math.floor(Number(micro) / 1000) : null;
    const meta = { sourceTimestamp: ts, timestampTrust: "EXCHANGE" as const, rightsStatus: "PUBLIC_ATTRIBUTED" as const, realtimeStatus: "REALTIME" as const };
    let observations: NormalizedObservation[] = [];
    if (r.kind === "trade") {
      observations = pairObservations(pairKey, base, quote, "bitstamp", { last: m.data.price }, { ...meta, sequence: typeof m.data.id === "number" ? m.data.id : null });
    } else if (r.kind === "book") {
      const bids = m.data.bids as unknown;
      const asks = m.data.asks as unknown;
      const bid = Array.isArray(bids) && Array.isArray(bids[0]) ? bids[0][0] : undefined;
      const ask = Array.isArray(asks) && Array.isArray(asks[0]) ? asks[0][0] : undefined;
      observations = pairObservations(pairKey, base, quote, "bitstamp", { bid, ask }, meta);
    }
    return { observations };
  },
  fixturesDir: "fixtures",
});