// Node.js API server to fetch and merge Slovak company data by IČO
// from two Finančná správa SR API endpoints with 404-safe handling

const express = require("express");
const axios = require("axios");

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

// Insert your API key below
const API_KEY = "2t5lK487ces7Rc4oEHrIwCjB5DpoZUBChQxCLBiSrwGNdEubKpraAtQLEiJmPXkdjNw5FssYpuO0LXSZpk3U6oqePyFaIGHokg4WNPEM0302X2BK4iXpkFv9Qg7jyeUXh50bWVExVrVSBuOnOQpBzzdJ1k1D54b115MD3y5ticWxvGDLUaqLQgA6nzFgbYOx6dR0ToJUxU714TetLBZCBy0xKSnBaOrxYv10I1gZ1q4rQx4Q8k7BTR6MaP";

// Safe fetch wrapper to handle 404 as empty result
async function fetchSafe(url) {
  try {
    const res = await axios.get(url, {
      headers: {
        accept: "application/json",
        key: API_KEY
      }
    });
    return res.data?.data || [];
  } catch (err) {
    if (err.response?.status === 404) {
      return []; // return empty list if not found
    }
    throw err;
  }
}

// API endpoint: /api/lookup?ico=XXXXXXXX
app.get("/api/lookup", async (req, res) => {
  const ico = req.query.ico;

  if (!ico) {
    return res.status(400).json({ error: "Missing ICO parameter" });
  }

  const endpoints = [
    `https://iz.opendata.financnasprava.sk/api/data/ds_dsrdp/search?page=1&column=ico&search=${ico}`,
    `https://iz.opendata.financnasprava.sk/api/data/ds_dphs/search?page=1&column=ico&search=${ico}`
  ];

  try {
    const [data1, data2] = await Promise.all([
      fetchSafe(endpoints[0]),
      fetchSafe(endpoints[1])
    ]);

    const merged = [...data1, ...data2].filter(
      (item, index, self) =>
        index === self.findIndex((t) =>
          JSON.stringify(t) === JSON.stringify(item)
        )
    );

    res.json({
      source1_count: data1.length,
      source2_count: data2.length,
      merged_count: merged.length,
      data: merged
    });
  } catch (error) {
    res.status(500).json({ error: error.message });
  }
});

app.listen(PORT, () => {
  console.log(`API server running at http://localhost:${PORT}`);
});