const cache = require('../cache');

const SANCTIONS_NAMES = [
  'IVANOV PETR', 'KIM JONG UN', 'RODRIGUEZ CARLOS', 'AL-RASHID OMAR',
  'PETROV SERGEI', 'WANG WEI', 'MULLER HANS', 'SILVA ANA', 'NAKAMURA YUKI', 'PETROVA ANNA'
];

let txCounter = 0;
const hitsTimeline = [];
const riskBuckets = { low: 0, medium: 0, high: 0, critical: 0 };

async function loadSanctions() {
  const cached = cache.get('sanctions-list', 24 * 60 * 60 * 1000);
  if (cached) return cached;
  const list = SANCTIONS_NAMES.map((name, i) => ({
    id: i + 1, name, list: 'EU Consolidated', country: ['RU', 'KP', 'VE', 'SY', 'RU', 'CN', 'DE', 'BR', 'JP', 'RU'][i]
  }));
  cache.set('sanctions-list', list);
  return list;
}

function generateTx(sanctions) {
  txCounter++;
  const hit = Math.random() < 0.09;
  const name = hit
    ? sanctions[Math.floor(Math.random() * sanctions.length)].name
    : `CUSTOMER ${Math.floor(Math.random() * 9000 + 1000)}`;
  const amount = +(Math.random() * 50000 + 100).toFixed(2);
  const risk = hit ? Math.round(85 + Math.random() * 15) : Math.round(Math.random() * 55);
  if (risk < 25) riskBuckets.low++;
  else if (risk < 50) riskBuckets.medium++;
  else if (risk < 75) riskBuckets.high++;
  else riskBuckets.critical++;

  const tx = {
    id: `TX-${Date.now()}-${txCounter}`,
    name, amount,
    currency: ['EUR', 'USD', 'GBP'][Math.floor(Math.random() * 3)],
    country: ['NL', 'DE', 'BE', 'FR', 'UK', 'US', 'RU', 'CN'][Math.floor(Math.random() * 8)],
    risk, hit,
    type: ['SEPA', 'SWIFT', 'CARD', 'CRYPTO'][Math.floor(Math.random() * 4)],
    ts: new Date().toISOString()
  };
  return tx;
}

async function getFraudSnapshot() {
  const sanctions = await loadSanctions();
  const recent = Array.from({ length: 25 }, () => generateTx(sanctions));
  const hits = recent.filter(t => t.hit).length;

  hitsTimeline.push({ t: new Date().toISOString().slice(11, 19), hits, screened: recent.length });
  if (hitsTimeline.length > 30) hitsTimeline.shift();

  const countryRisk = ['NL', 'DE', 'BE', 'FR', 'UK', 'US', 'RU', 'CN'].map(c => ({
    country: c,
    txs: Math.round(50 + Math.random() * 200),
    hits: c === 'RU' || c === 'CN' ? Math.round(3 + Math.random() * 8) : Math.round(Math.random() * 2)
  }));

  const riskDistribution = [
    { name: 'Laag', value: riskBuckets.low || 120, fill: '#22c55e' },
    { name: 'Medium', value: riskBuckets.medium || 80, fill: '#f59e0b' },
    { name: 'Hoog', value: riskBuckets.high || 40, fill: '#f97316' },
    { name: 'Kritiek', value: riskBuckets.critical || 15, fill: '#ef4444' }
  ];

  const typeBreakdown = [
    { type: 'SEPA', blocked: Math.round(Math.random() * 5), cleared: 420 },
    { type: 'SWIFT', blocked: Math.round(Math.random() * 8), cleared: 180 },
    { type: 'CARD', blocked: Math.round(Math.random() * 12), cleared: 890 },
    { type: 'CRYPTO', blocked: Math.round(Math.random() * 15), cleared: 65 }
  ];

  const insights = [
    { type: 'warn', label: 'Compliance', text: `${sanctions.length} entiteiten op EU-lijst — elke tx gescored in <20ms.` },
    { type: 'info', label: 'ML', text: 'Velocity + geo-mismatch rules vangen 94% demo-anomalies — uitbreidbaar met eigen modellen.' },
    { type: 'ok', label: 'Audit', text: 'Volledige audit trail exporteerbaar voor DNB/AFM toezicht.' },
    { type: 'warn', label: 'Hits', text: `${hits} hits in huidige batch — RU/CN geo-risico geconcentreerd.` },
    { type: 'info', label: 'Throughput', text: `${1240 + Math.floor(Math.random() * 50)} tx/min — SSE stream elke 1,5s.` },
    { type: 'ok', label: 'Actie', text: 'False-positive review queue koppelbaar — zelfde Global Ops UI als treasury & retail.' }
  ];

  const contextBlocks = [
    { title: 'Waarom Fraud Command Center?', body: 'Financiële instellingen moeten sancties, PEP en anomalies combineren — realtime, auditable, zonder vendor lock-in.' },
    { title: 'Wat u hier ziet', body: 'Live tx stream, sanctions hits, risk verdeling, geo-risico en type breakdown — refresh elke 1,5 seconden.' },
    { title: 'Technische aanpak Mek-Tech', body: 'EU Consolidated List + rule engine + SSE. ML models plug-in ready. Geen opslag van demo-tx.' },
    { title: 'ROI voor uw organisatie', body: 'Snellere compliance response, lagere false-positive kosten, audit-ready logging.' },
    { title: 'Productie-architectuur', body: 'Payment gateway → screening service → Kafka audit log → dit dashboard + case management.' },
    { title: 'Volgende stap', body: 'Pilot met echte sanctions feed + 3 custom rules — productie POC binnen 3 weken.' }
  ];

  return {
    ts: new Date().toISOString(),
    refreshMs: 1500,
    sanctionsCount: sanctions.length,
    recent,
    hitsLastMinute: hits,
    hitsTimeline: [...hitsTimeline],
    countryRisk,
    riskDistribution,
    typeBreakdown,
    avgLatencyMs: Math.round(12 + Math.random() * 8),
    screeningRate: 1240 + Math.floor(Math.random() * 50),
    blockRate: +(hits / recent.length * 100).toFixed(2),
    insights,
    contextBlocks,
    criticalCount: recent.filter(t => t.risk > 85).length,
    context: {
      pitch: 'Global Fraud & Compliance Operations — sanctions screening live.',
      deployment: 'EU Consolidated List · OpenSanctions · ECB Payment Stats'
    }
  };
}

module.exports = { getFraudSnapshot, generateTx, loadSanctions };