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

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

  async getTripLiveStatus(tripId: string) {
    const trip = await this.prisma.trip.findUnique({
      where: { id: tripId },
      include: { service: true, originStation: true, destinationStation: true, liveStatus: true, stopTimes: { include: { station: true }, orderBy: { sequence: 'asc' } } },
    });
    if (!trip) throw new NotFoundException('Trip not found');
    const live = trip.liveStatus;
    const nextStop = trip.stopTimes.find((s) => s.status === 'UPCOMING' || s.status === 'APPROACHING');
    return {
      tripId: trip.id, trainName: trip.service.name,
      fromStationName: trip.originStation.name, toStationName: trip.destinationStation.name,
      state: live?.state ?? trip.status, currentLocationLabel: live?.currentLocationLabel,
      progressPercent: live?.progressPercent ?? 0, delayMinutes: live?.delayMinutes ?? 0,
      currentSpeedKph: live?.currentSpeedKph, platformLabel: live?.platformLabel,
      nextStopStationName: nextStop?.station.name, updatedAt: live?.updatedAt ?? trip.departureAt,
    };
  }

  updateLiveStatus(tripId: string, data: any) {
    return this.prisma.tripLiveStatus.upsert({ where: { tripId }, update: data, create: { tripId, state: data.state ?? 'SCHEDULED', ...data } });
  }

  getStopTimeline(tripId: string) { return this.prisma.tripStopTime.findMany({ where: { tripId }, include: { station: true }, orderBy: { sequence: 'asc' } }); }

  getStationCrowdSignals() { return this.prisma.stationCrowdSignal.findMany({ include: { station: true } }); }

  getWeatherAlerts() { return this.prisma.weatherAlert.findMany({ where: { validUntil: { gte: new Date() } }, orderBy: { createdAt: 'desc' } }); }
}