/**
 * DataService — couche d'abstraction entre l'UI et les sources de données.
 *
 * Mode mock  (USE_LIVE_API = false) : données simulées, aucun appel réseau.
 * Mode live  (USE_LIVE_API = true)  : données réelles Ğ1v2.
 *   - Transactions   : Subsquid indexer  https://squidv2s.syoul.fr/v1/graphql
 *   - Géolocalisation : Cesium+           https://g1.data.e-is.pro
 *     → lookup par clé Duniter (_id) via conversion SS58 → base58 Ed25519
 *     → membres migrés v1→v2 : clé genesis (previousId) = _id Cesium+
 *     → carte d'identité (keyMap) mise en cache 10 min, 1 seule requête
 *
 * Pour activer : définir VITE_USE_LIVE_API=true dans .env.local
 */

import { fetchTransfers, buildIdentityKeyMap, fetchCurrentUD, ss58ToDuniterKey } from './adapters/SubsquidAdapter';
import { resolveGeoByKeys, cleanCityName } from './adapters/CesiumAdapter';
import {
  getTransactionsForPeriod,
  computeStats,
  type Transaction,
} from '../data/mockData';
import {
  buildMockArcs,
  type TransactionArc,
} from '../data/arcData';

const USE_LIVE_API = import.meta.env.VITE_USE_LIVE_API === 'true';

// Cache du DU courant, valide 1 heure (le DU change tous les ~6 mois)
let udCache: { value: number; expiresAt: number } | null = null;

async function getCurrentUD(): Promise<number> {
  if (udCache && Date.now() < udCache.expiresAt) return udCache.value;
  const value = await fetchCurrentUD();
  udCache = { value, expiresAt: Date.now() + 60 * 60 * 1000 };
  return value;
}

// Cache de la carte identité SS58→DuniterKey, valide 10 minutes
let keyMapCache: { map: Map<string, string>; expiresAt: number } | null = null;

async function getIdentityKeyMap(): Promise<Map<string, string>> {
  if (keyMapCache && Date.now() < keyMapCache.expiresAt) return keyMapCache.map;
  const map = await buildIdentityKeyMap();
  keyMapCache = { map, expiresAt: Date.now() + 10 * 60 * 1000 };
  return map;
}

async function fetchLiveTransactions(periodDays: number): Promise<{
  geolocated:    Transaction[];
  arcs:          TransactionArc[];
  totalCount:    number;
  totalVolume:   number;
  allTimestamps: number[];
}> {
  // ~400 tx/jour sur le réseau Ğ1v2 → marge ×1.5 arrondie, minimum 2000
  const limit = Math.max(2000, Math.ceil(periodDays * 600));
  const { transfers: rawTransfers, totalCount } = await fetchTransfers(periodDays, limit);
  if (rawTransfers.length === 0) return { geolocated: [], arcs: [], totalCount: 0, totalVolume: 0, allTimestamps: [] };

  const totalVolume = rawTransfers.reduce((s, t) => s + t.amount, 0);

  // Carte SS58 courant → clé Duniter (= _id Cesium+)
  let keyMap = new Map<string, string>();
  try {
    keyMap = await getIdentityKeyMap();
  } catch (err) {
    console.warn('Identity key map indisponible :', err);
  }

  // Clés Duniter uniques des émetteurs ET destinataires (un seul appel Cesium+)
  // Pour les membres WoT : via keyMap (genesis key = _id Cesium+)
  // Pour les non-membres : conversion directe SS58 → Duniter key
  const resolveKey = (ss58: string): string =>
    keyMap.get(ss58) ?? ss58ToDuniterKey(ss58);

  const allDuniterKeys = [...new Set([
    ...rawTransfers.map((t) => t.fromId ? resolveKey(t.fromId) : undefined),
    ...rawTransfers.map((t) => t.toId   ? resolveKey(t.toId)   : undefined),
  ].filter(Boolean) as string[])];

  // Résolution géo par clé Duniter (_id Cesium+)
  let geoMap = new Map<string, { lat: number; lng: number; city: string; countryCode: string }>();
  try {
    const profiles = await resolveGeoByKeys(allDuniterKeys);
    for (const [key, p] of profiles) {
      geoMap.set(key, { lat: p.lat, lng: p.lng, city: p.city, countryCode: p.countryCode });
    }
  } catch (err) {
    console.warn('Cesium+ indisponible :', err);
  }

  const geolocated: Transaction[]   = [];
  const arcs:       TransactionArc[] = [];

  for (const t of rawTransfers) {
    const fromDuniterKey = t.fromId ? resolveKey(t.fromId) : undefined;
    if (!fromDuniterKey) continue;
    const fromGeo = geoMap.get(fromDuniterKey);
    if (!fromGeo) continue;

    const fromCity = cleanCityName(fromGeo.city);

    // Heatmap : émetteur géolocalisé
    geolocated.push({
      id:          t.id,
      timestamp:   t.timestamp,
      lat:         fromGeo.lat,
      lng:         fromGeo.lng,
      amount:      t.amount,
      city:        fromCity,
      countryCode: fromGeo.countryCode,
      fromKey:     t.fromId,
      toKey:       t.toId,
    });

    // Arc : les deux extrémités géolocalisées + villes différentes
    const toDuniterKey = t.toId ? resolveKey(t.toId) : undefined;
    if (!toDuniterKey) continue;
    const toGeo = geoMap.get(toDuniterKey);
    if (!toGeo) continue;

    const toCity = cleanCityName(toGeo.city);
    if (fromCity === toCity) continue;

    arcs.push({
      id:          `${t.id}-arc`,
      timestamp:   t.timestamp,
      amount:      t.amount,
      fromLat: fromGeo.lat, fromLng: fromGeo.lng,
      fromCity,             fromCountry: fromGeo.countryCode,
      fromKey: t.fromId,
      toLat: toGeo.lat,     toLng: toGeo.lng,
      toCity,               toCountry: toGeo.countryCode,
      toKey: t.toId,
    });
  }

  return { geolocated, arcs, totalCount, totalVolume, allTimestamps: rawTransfers.map((t) => t.timestamp) };
}

// ---------------------------------------------------------------------------
// Public API
// ---------------------------------------------------------------------------
export interface PeriodStats {
  totalVolume:      number;
  transactionCount: number;  // total blockchain (y compris non-géolocalisés)
  geoCount:         number;  // transactions visibles sur la carte
  topCities: { name: string; volume: number; count: number; countryCode: string }[];
}

export interface DataResult {
  transactions:  Transaction[];    // uniquement géolocalisées → heatmap
  arcs:          TransactionArc[]; // les deux extrémités géolocalisées → vue flux
  stats:         PeriodStats;
  source:        'live' | 'mock';
  currentUD:     number;           // valeur du DU courant en Ğ1
  allTimestamps: number[];         // timestamps de TOUS les transfers (géo + non-géo)
}

export async function fetchData(periodDays: number): Promise<DataResult> {
  if (!USE_LIVE_API) {
    await new Promise((r) => setTimeout(r, 80));
    const transactions = getTransactionsForPeriod(periodDays);
    const base = computeStats(transactions);
    const arcs = buildMockArcs(transactions);
    return {
      transactions,
      arcs,
      stats: { ...base, geoCount: transactions.length },
      source: 'mock',
      currentUD: 11.78,
      allTimestamps: transactions.map((t) => t.timestamp),
    };
  }

  const [{ geolocated, arcs, totalCount, totalVolume, allTimestamps }, currentUD] = await Promise.all([
    fetchLiveTransactions(periodDays),
    getCurrentUD(),
  ]);
  const base = computeStats(geolocated);

  return {
    transactions: geolocated,
    arcs,
    stats: {
      totalVolume,
      transactionCount: totalCount,
      geoCount: geolocated.length,
      topCities: base.topCities,
    },
    source: 'live',
    currentUD,
    allTimestamps,
  };
}