import express from "express";
import http from "http";
import { WebSocketServer } from "ws";
import cors from "cors";
import pkg from "pg";

const { Pool } = pkg;

const app = express();
const PORT = 3000;

// Setup Postgres connection pool
const pool = new Pool({
  connectionString: process.env.DATABASE_URL || "neverleavetheconnectionstringhereforproduction",
});

app.use(cors());

// HTTP GET /games/:id → return game info from DB
app.get("/games/:id", async (req, res) => {
  const gameId = req.params.id;
  try {
    const result = await pool.query("SELECT info FROM items WHERE id = $1", [gameId]);
    if (result.rows.length === 0) {
      return res.redirect(302, "https://engine.battlesnake.com");
      // return res.status(404).json({ error: "Game not found" });

    }
    res.json(result.rows[0].info); // send back the JSONB field
  } catch (err) {
    console.error(err);
    res.status(500).json({ error: "Database error" });
  }
});

// Create HTTP server and attach WebSocket server
const server = http.createServer(app);
const wss = new WebSocketServer({ server });

// Helper to match the path pattern
function matchGameEventsPath(url) {
  if (!url) return null;
  const match = url.match(/^\/games\/([^\/]+)\/events$/);
  return match ? match[1] : null;
}

wss.on("connection", async (ws, req) => {
  const gameId = matchGameEventsPath(req.url);
  if (!gameId) {
    ws.close();
    return;
  }

  console.log(`WS client connected for game: ${gameId}`);

  try {
    // Grab frames array from DB
    const result = await pool.query("SELECT frames FROM items WHERE id = $1", [gameId]);
    if (result.rows.length === 0) {
      ws.send(JSON.stringify({ error: "Game not found" }));
      ws.close();
      return;
    }

    const frames = result.rows[0].frames || [];

    // Stream frames one by one with delay
    frames.forEach((frame, i) => {
      setTimeout(() => {
        if (ws.readyState === ws.OPEN) {
          ws.send(JSON.stringify(frame));
        }
      }, i * 5); // staggered delay
    });

  } catch (err) {
    console.error(err);
    ws.send(JSON.stringify({ error: "Database error" }));
    ws.close();
  }
});

server.listen(PORT, "0.0.0.0", () => {
  console.log(`Server running at http://localhost:${PORT} (HTTP + WebSocket)`);
});