import { Injectable } from '@nestjs/common';
import { PrismaService } from '../../common/prisma.service';

@Injectable()
export class DashboardService {
  constructor(private prisma: PrismaService) {}

  async getHomeDashboard(passengerId: string) {
    const now = new Date();
    const [passenger, upcomingBooking, wallet, promos, weatherAlerts, stationSignals, savedRoutes] = await Promise.all([
      this.prisma.passenger.findUnique({ where: { id: passengerId }, include: { user: { select: { fullName: true } }, loyalty: true } }),
      this.prisma.booking.findFirst({
        where: { passengerId, status: 'CONFIRMED', schedule: { departureAt: { gte: now } } },
        include: {
          schedule: { include: { originStation: true, destinationStation: true, train: true, liveStatus: true } },
          seats: { include: { seat: { include: { coach: true } } }, take: 1 },
          ticket: true,
        },
        orderBy: { createdAt: 'asc' },
      }),
      this.prisma.walletAccount.findUnique({ where: { passengerId } }),
      this.prisma.promotion.count({ where: { active: true, validUntil: { gte: now } } }),
      this.prisma.weatherAlert.findMany({ where: { validUntil: { gte: now } }, take: 3 }),
      this.prisma.stationCrowdSignal.findMany({ include: { station: true }, take: 5 }),
      this.prisma.savedRoute.findMany({ where: { passengerId }, orderBy: { tripCount: 'desc' }, take: 5 }),
    ]);

    const hour = now.getHours();
    const greetingKey = hour < 12 ? 'MORNING' : hour < 17 ? 'AFTERNOON' : 'EVENING';
    const firstName = passenger?.user.fullName.split(' ')[0] ?? '';
    const seat = upcomingBooking?.seats[0];

    return {
      user: { firstName, greetingKey },
      upcomingTicket: upcomingBooking ? {
        ticketId: upcomingBooking.ticket?.id, bookingRef: upcomingBooking.bookingRef,
        from: upcomingBooking.schedule.originStation.name, to: upcomingBooking.schedule.destinationStation.name,
        trainName: upcomingBooking.schedule.train.name, coachLabel: seat?.seat.coach.number, seatLabel: seat?.seat.seatNumber,
        departureAt: upcomingBooking.schedule.departureAt,
        punctualityLabel: (upcomingBooking.schedule.liveStatus?.delayMinutes ?? 0) > 0 ? 'DELAYED' : 'ON_TIME',
      } : null,
      wallet: wallet ? { balanceMinor: wallet.balanceMinor, currency: wallet.currency } : null,
      activePromotionsCount: promos,
      weatherAlerts: weatherAlerts.map((w) => ({ id: w.id, title: w.title, message: w.message, severity: w.severity })),
      stationSignals: stationSignals.map((s) => ({ stationId: s.stationId, stationName: s.station.name, level: s.level, statusLabel: s.statusLabel })),
      savedRoutes: savedRoutes.map((r) => ({ id: r.id, fromName: r.fromName, toName: r.toName, tripCount: r.tripCount })),
    };
  }
}
