import 'dotenv/config';
import { PrismaClient, TrashType } from '@prisma/client';

const prisma = new PrismaClient();

/**
 * Öffentliche Schnittstelle der Kommunalen Abfallwirtschaft Mainz und
 * Mainz-Bingen AöR (https://lk.kaw-mainz-bingen.de/de/Abfallentsorgung/Abfallkalender),
 * kein API-Key/Login nötig. CityId 35 = Nackenheim, DistrictId 5 =
 * Verbandsgemeinde Bodenheim (per Browser-Formular ermittelt).
 */
const API_BASE = 'https://abfallkalender-api-lk.kaw-mainz-bingen.de/public/frontend/collectiondates';
const CITY_ID = 35;
const DISTRICT_ID = 5;
const SYNC_MONTHS_AHEAD = 6;

// Deren WasteTypeId -> unser TrashType. Sperrmüll (5) und Problemmüllbus (6)
// kennt unser Schema nicht und werden übersprungen.
const WASTE_TYPE_MAP: Record<number, TrashType> = {
  1: 'RESTMUELL',
  2: 'BIOMUELL',
  3: 'GELBER_SACK',
  4: 'PAPIER',
};

interface KawCollectionDate {
  WasteTypeId: number;
  WasteTypeName: string;
  Date: string; // "TT.MM.JJJJ"
}

interface KawResponse {
  DataList: KawCollectionDate[];
  TotalRecords: number;
}

function parseGermanDate(value: string): Date {
  const [day, month, year] = value.split('.').map(Number);
  return new Date(Date.UTC(year, month - 1, day));
}

async function fetchAllPages(dateFrom: string, dateTo: string): Promise<KawCollectionDate[]> {
  const results: KawCollectionDate[] = [];
  let page = 1;
  while (true) {
    const url =
      `${API_BASE}?Filter.CityId=${CITY_ID}&Filter.DistrictId=${DISTRICT_ID}` +
      `&Filter.DateFrom=${dateFrom}&Filter.DateTo=${dateTo}&Filter.CurrentPage=${page}`;
    const res = await fetch(url);
    if (!res.ok) throw new Error(`KAW-API antwortete mit Status ${res.status}`);
    const body = (await res.json()) as KawResponse;
    results.push(...body.DataList);
    if (results.length >= body.TotalRecords || body.DataList.length === 0) break;
    page += 1;
  }
  return results;
}

export async function runTrashCalendarSyncJob(referenceDate: Date = new Date()) {
  const dateFrom = referenceDate.toISOString().slice(0, 10);
  const dateTo = new Date(referenceDate);
  dateTo.setMonth(dateTo.getMonth() + SYNC_MONTHS_AHEAD);
  const dateToStr = dateTo.toISOString().slice(0, 10);

  const entries = await fetchAllPages(dateFrom, dateToStr);

  let created = 0;
  let skippedUnknownType = 0;

  for (const entry of entries) {
    const type = WASTE_TYPE_MAP[entry.WasteTypeId];
    if (!type) {
      skippedUnknownType += 1;
      continue;
    }
    const date = parseGermanDate(entry.Date);
    const existing = await prisma.trashSchedule.findUnique({ where: { type_date: { type, date } } });
    if (existing) continue;
    await prisma.trashSchedule.create({ data: { type, date } });
    created += 1;
  }

  return { fetched: entries.length, created, skippedUnknownType };
}

if (require.main === module) {
  runTrashCalendarSyncJob()
    .then((result) => {
      console.log(
        `[trashCalendarSyncJob] ${result.fetched} Termine von der KAW-API geladen, ` +
          `${result.skippedUnknownType} unbekannte Mülltypen übersprungen.`,
      );
      return prisma.$disconnect();
    })
    .catch((err) => {
      console.error('[trashCalendarSyncJob] Fehlgeschlagen:', err);
      process.exit(1);
    });
}