const express = require('express');
const bodyParser = require('body-parser');
const sqlite3 = require('sqlite3').verbose();
const app = express();
const port = 3000;

// Serve static files (your front-end) from the current directory
app.use(express.static(__dirname));
app.use(bodyParser.json());

// Open (or create) SQLite database
const db = new sqlite3.Database('./data.db', (err) => {
  if (err) {
    console.error("Could not connect to database:", err.message);
  } else {
    console.log('Connected to SQLite database.');
  }
});

// Create table if it doesn't exist
db.run(`CREATE TABLE IF NOT EXISTS coinTrackers (
  id TEXT PRIMARY KEY,
  data TEXT
)`);

// GET endpoint to retrieve coin tracker data, filtering out trackers without any non-default rows
app.get('/api/coinTrackers', (req, res) => {
  db.all(`SELECT * FROM coinTrackers`, [], (err, rows) => {
    if (err) {
      res.status(500).json({ error: err.message });
      return;
    }
    const trackers = rows
      .map(row => JSON.parse(row.data))
      .filter(tracker => {
        if (tracker.rows && tracker.rows.length > 0) {
          return tracker.rows.some(r => {
            const base = parseFloat(r.baseCapital) || 0;
            const income = parseFloat(r.income) || 0;
            const dailyYield = parseFloat(r.dailyYield) || 0;
            return base !== 0 || income !== 0 || dailyYield !== 0;
          });
        }
        return false;
      });
    res.json({ data: trackers });
  });
});

// POST endpoint to save/update coin tracker data
// This version clears out existing data before inserting the current trackers from the client.
app.post('/api/coinTrackers', (req, res) => {
  const trackers = req.body.data; // Expecting an array of tracker objects

  // Clear out all existing trackers from the database
  db.run(`DELETE FROM coinTrackers`, [], function(err) {
    if (err) {
      res.status(500).json({ error: err.message });
      return;
    }
    // Insert all current trackers
    const stmt = db.prepare(`INSERT OR REPLACE INTO coinTrackers (id, data) VALUES (?, ?)`);
    trackers.forEach(tracker => {
      stmt.run(tracker.id, JSON.stringify(tracker));
    });
    stmt.finalize(err => {
      if (err) {
        res.status(500).json({ error: err.message });
        return;
      }
      res.json({ message: "Data saved successfully." });
    });
  });
});

app.listen(port, () => {
  console.log(`Server is running on port ${port}`);
});