import express from 'express';
import path from 'path';
import { db } from '../db/client.js';
import { isMarketOpen } from '../tracker/market-hours.js';


export function createServer(): express.Application {
  const app = express();
  app.use(express.json());

  // Serve the static UI from /public
  const publicDir = path.resolve(__dirname, '../../public');
  app.use(express.static(publicDir));

  // ── GET /api/positions ────────────────────────────────────────────────────
  // Returns all currently tracked positions (open + recently closed)
  app.get('/api/positions', (_req, res) => {
    const rows = db.prepare(`
      SELECT key, exchange, tradingsymbol, instrumenttype, producttype,
             netqty, ltp, avg_price, unrealised_pnl, realised_pnl, total_pnl,
             source, is_closed, updated_at
      FROM positions
      ORDER BY ABS(total_pnl) DESC
    `).all();
    res.json({ ok: true, data: rows });
  });

  // ── GET /api/alerts ───────────────────────────────────────────────────────
  // Alert history, newest first, optional ?limit=N&symbol=X
  app.get('/api/alerts', (req, res) => {
    const limit = Math.min(parseInt(req.query.limit as string) || 50, 200);
    const symbol = req.query.symbol as string | undefined;

    let query = `SELECT * FROM alerts`;
    const params: (string | number)[] = [];

    if (symbol) {
      query += ` WHERE tradingsymbol = ?`;
      params.push(symbol);
    }
    query += ` ORDER BY alerted_at DESC LIMIT ?`;
    params.push(limit);

    const rows = db.prepare(query).all(...params);
    res.json({ ok: true, data: rows });
  });

  // ── GET /api/config ───────────────────────────────────────────────────────
  app.get('/api/config', (_req, res) => {
    const rows = db.prepare(`SELECT * FROM position_config`).all();
    res.json({
      ok: true,
      global: {
        alertThresholdPct: parseFloat(process.env.ALERT_THRESHOLD_PCT || '5'),
        alertMinAbsInr: parseFloat(process.env.ALERT_MIN_ABS_INR || '100'),
        pollIntervalSeconds: parseInt(process.env.POLL_INTERVAL_SECONDS || '60'),
      },
      overrides: rows,
    });
  });

  // ── PUT /api/config/:key ──────────────────────────────────────────────────
  // Set per-position threshold or mute
  app.put('/api/config/:key', (req, res) => {
    const { key } = req.params;
    const { alert_threshold_pct, muted_until, notes } = req.body;

    db.prepare(`
      INSERT INTO position_config (position_key, alert_threshold_pct, muted_until, notes)
      VALUES (?, ?, ?, ?)
      ON CONFLICT(position_key) DO UPDATE SET
        alert_threshold_pct = excluded.alert_threshold_pct,
        muted_until = excluded.muted_until,
        notes = excluded.notes
    `).run(key, alert_threshold_pct ?? null, muted_until ?? null, notes ?? null);

    res.json({ ok: true });
  });

  // ── GET /api/health ───────────────────────────────────────────────────────
  app.get('/api/health', (_req, res) => {
    const lastError = db.prepare(
      `SELECT error, occurred_at FROM poll_errors ORDER BY occurred_at DESC LIMIT 1`
    ).get() as { error: string; occurred_at: string } | undefined;

    const posCount = (db.prepare(`SELECT COUNT(*) as n FROM positions WHERE is_closed = 0`).get() as { n: number }).n;

    res.json({
      ok: true,
      marketOpen: isMarketOpen(),
      openPositions: posCount,
      lastError: lastError ?? null,
      uptime: Math.floor(process.uptime()),
    });
  });

  // Catch-all: serve index.html for SPA routing
  app.get('*', (_req, res) => {
    res.sendFile(path.join(publicDir, 'index.html'));
  });

  return app;
}