server.mjs

import express from 'express';
import cors from 'cors';
import fs from 'fs';
import { createClient } from 'db-vendo-client';
import { profile as dbVendoProfile } from 'db-vendo-client/p/db/index.js';

// Default settings
let settings = {
  port: 3000,
  locations: { defaultResults: 8 },
  journeys: { defaultResults: 5, includeStopovers: true },
  departures: { defaultDuration: 60 }
};

const settingsPath = './settings.json';
if (fs.existsSync(settingsPath)) {
  try {
    const parsed = JSON.parse(fs.readFileSync(settingsPath, 'utf8'));
    settings = {
      port: parsed.port || settings.port,
      locations: { ...settings.locations, ...parsed.locations },
      journeys:  { ...settings.journeys,  ...parsed.journeys  },
      departures:{ ...settings.departures,...parsed.departures }
    };
  } catch (e) {
    console.error('Fehler beim Lesen von settings.json:', e.message);
  }
}

// Maps frontend/query product names to db-vendo-client product IDs
const PRODUCT_MAP = {
  'long-distance-train': ['nationalExpress', 'national'],
  'regional-train':      ['regionalExpress', 'regional', 'suburban'],
  'tram':                ['tram'],
  'bus':                 ['bus'],
  'subway':              ['subway'],
  'ferry':               ['ferry'],
};
const ALL_PRODUCTS = ['nationalExpress', 'national', 'regionalExpress', 'regional', 'suburban', 'bus', 'ferry', 'subway', 'tram', 'taxi'];

function parseProducts(productsParam) {
  if (!productsParam) return null;
  const requested = productsParam.split(',').flatMap(p => PRODUCT_MAP[p] ?? []);
  return Object.fromEntries(ALL_PRODUCTS.map(p => [p, requested.includes(p)]));
}

async function resolveStation(client, value) {
  if (/^\d{6,}$/.test(value)) return value;
  const hits = await client.locations(value, { results: 1, stops: true, addresses: false });
  if (!hits.length) throw new Error(`Haltestelle nicht gefunden: "${value}"`);
  return hits[0].id;
}

const app = express();
const port = process.env.PORT || settings.port;

const client = createClient(dbVendoProfile, 'db-api-wrapper');

app.use(cors());
app.use(express.json());

// Health check
app.get('/', (req, res) => {
  res.json({ message: 'DB API Wrapper is running!', version: '1.0.0' });
});

// 1. Haltestellen / Orte suchen
app.get('/locations', async (req, res) => {
  try {
    const { query, results } = req.query;
    if (!query) return res.status(400).json({ error: 'Parameter "query" ist erforderlich' });
    const locations = await client.locations(query, {
      results: results ? parseInt(results) : settings.locations.defaultResults,
      stops: true,
      addresses: true,
      poi: false,
    });
    res.json(locations);
  } catch (err) {
    res.status(500).json({ error: err.message });
  }
});

// 2. Routen berechnen
app.get('/journeys', async (req, res) => {
  try {
    const { from, to } = req.query;
    if (!from || !to) return res.status(400).json({ error: 'Parameter "from" und "to" sind erforderlich' });

    const fromId = await resolveStation(client, from);
    const toId   = await resolveStation(client, to);

    const options = {
      results:   req.query.results ? parseInt(req.query.results) : settings.journeys.defaultResults,
      stopovers: settings.journeys.includeStopovers,
    };

    if (req.query.departure) options.departure = new Date(req.query.departure);
    if (req.query.bike !== undefined) options.bike = req.query.bike === 'true';
    if (req.query.accessibility) options.accessibility = req.query.accessibility;
    if (req.query.transfers !== undefined && req.query.transfers !== '') options.transfers = parseInt(req.query.transfers);

    const products = parseProducts(req.query.products);
    if (products) options.products = products;

    const data = await client.journeys(fromId, toId, options);
    res.json(data);
  } catch (err) {
    res.status(500).json({ error: err.message });
  }
});

// 3. Abfahrtsmonitor
app.get('/departures', async (req, res) => {
  try {
    const { station, duration } = req.query;
    if (!station) return res.status(400).json({ error: 'Parameter "station" ist erforderlich' });

    const stationId = await resolveStation(client, station);
    const data = await client.departures(stationId, {
      duration: duration ? parseInt(duration) : settings.departures.defaultDuration,
    });
    res.json(data);
  } catch (err) {
    res.status(500).json({ error: err.message });
  }
});

// Serve index.html at /ui — keeps GET / free for the JSON health check
app.use(express.static('.'));

app.listen(port, () => {
  console.log(`DB API Wrapper läuft auf http://localhost:${port}`);
  console.log(`Beispiel: http://localhost:${port}/journeys?from=Frankfurt(Main)Hbf&to=Berlin+Hbf`);
});