import https from 'https';
import fs from 'fs';

const EN_KEYWORDS = [
  'receipt scanner to excel',
  'receipt to excel',
  'receipt scanner',
  'expense tracker',
  'tax receipt organizer',
  'receipt keeper',
  'invoice scanner',
  'bookkeeping scanner',
  'ocr receipt scanner',
  'extract receipt to csv'
];

const DE_KEYWORDS = [
  'beleg scanner',
  'belege digitalisieren',
  'kassenbon scanner',
  'quittung scanner',
  'spesen app',
  'rechnung scanner',
  'receipt to excel',
  'datev scanner',
  'belegmanager',
  'ausgaben tracker'
];

const STOREFRONTS = [
  { id: 'US', country: 'us', name: 'USA', lang: 'en' },
  { id: 'GB', country: 'gb', name: 'UK', lang: 'en' },
  { id: 'CA', country: 'ca', name: 'Kanada', lang: 'en' },
  { id: 'AU', country: 'au', name: 'Australien', lang: 'en' },
  { id: 'DE', country: 'de', name: 'Deutschland', lang: 'de' },
  { id: 'AT', country: 'at', name: 'Österreich', lang: 'de' },
  { id: 'CH', country: 'ch', name: 'Schweiz', lang: 'de' }
];

function fetchStoreData(term, country) {
  return new Promise((resolve) => {
    const url = `https://itunes.apple.com/search?term=${encodeURIComponent(term)}&country=${country}&entity=software&limit=10`;
    https.get(url, { headers: { 'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7)' } }, (res) => {
      let data = '';
      res.on('data', chunk => data += chunk);
      res.on('end', () => {
        try {
          const json = JSON.parse(data);
          resolve(json.results || []);
        } catch {
          resolve([]);
        }
      });
    }).on('error', () => resolve([]));
  });
}

function calculateDifficulty(apps, term) {
  if (!apps || apps.length === 0) return { score: 10, tier: 'Sehr gering' };

  const top5 = apps.slice(0, 5);
  const totalReviews = top5.reduce((sum, a) => sum + (a.userRatingCount || 0), 0);
  const avgReviews = totalReviews / top5.length;
  
  const titleMatches = top5.filter(a => (a.trackName || '').toLowerCase().includes(term.toLowerCase())).length;

  // Logarithmic scale for reviews
  let reviewScore = 0;
  if (avgReviews > 500000) reviewScore = 95;
  else if (avgReviews > 100000) reviewScore = 85;
  else if (avgReviews > 20000) reviewScore = 70;
  else if (avgReviews > 5000) reviewScore = 55;
  else if (avgReviews > 1000) reviewScore = 40;
  else if (avgReviews > 100) reviewScore = 25;
  else reviewScore = 15;

  const matchScore = titleMatches * 5;
  const finalScore = Math.min(99, Math.max(10, Math.round((reviewScore * 0.8) + (matchScore * 0.2))));

  return {
    score: finalScore,
    avgReviews: Math.round(avgReviews),
    top1: top5[0] ? `${top5[0].trackName} (${top5[0].userRatingCount || 0} rev, ★${top5[0].averageUserRating?.toFixed(1) || '0'})` : 'Keine',
    resultCount: apps.length
  };
}

async function run() {
  console.log("Starte Live-Abfrage der Apple Storefront API...");
  const report = {};

  for (const sf of STOREFRONTS) {
    console.log(`\nPrüfe Storefront: ${sf.name} (${sf.id})...`);
    report[sf.id] = { name: sf.name, data: [] };
    const keywords = sf.lang === 'de' ? DE_KEYWORDS : EN_KEYWORDS;

    for (const kw of keywords) {
      const apps = await fetchStoreData(kw, sf.country);
      const diff = calculateDifficulty(apps, kw);
      
      report[sf.id].data.push({
        keyword: kw,
        ...diff
      });
      await new Promise(r => setTimeout(r, 200));
    }
  }

  fs.writeFileSync('scripts/live_api_results.json', JSON.stringify(report, null, 2));
  console.log("\nLive-Ergebnisse erfolgreich in scripts/live_api_results.json gespeichert!");
}

run();