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

@Injectable()
export class EventsService {
  constructor(
    private readonly prisma: PrismaService,
    private readonly audit: AuditService,
  ) {}

  async list(tenantId: string, includeUnpublished = false) {
    return this.prisma.event.findMany({
      where: {
        tenantId,
        ...(includeUnpublished ? {} : { isPublished: true }),
      },
      orderBy: { startsAt: 'asc' },
      include: { _count: { select: { rsvps: true } } },
    });
  }

  async create(tenantId: string, adminId: string, dto: {
    title: string;
    description?: string;
    location?: string;
    startsAt: string;
    endsAt?: string;
    isPublished?: boolean;
  }) {
    const event = await this.prisma.event.create({
      data: {
        tenantId,
        title: dto.title,
        description: dto.description ?? null,
        location: dto.location ?? null,
        startsAt: new Date(dto.startsAt),
        endsAt: dto.endsAt ? new Date(dto.endsAt) : null,
        createdBy: adminId,
        isPublished: dto.isPublished ?? false,
      },
    });

    await this.audit.log({
      tenantId,
      actorId: adminId,
      action: AuditAction.EVENT_CREATED,
      resourceType: 'Event',
      resourceId: event.id,
      payload: { title: event.title, isPublished: event.isPublished },
    });

    return event;
  }

  async update(tenantId: string, adminId: string, eventId: string, dto: {
    title?: string;
    description?: string;
    location?: string;
    startsAt?: string;
    endsAt?: string;
    isPublished?: boolean;
  }) {
    const event = await this.prisma.event.findFirst({ where: { id: eventId, tenantId } });
    if (!event) throw new NotFoundException('Event not found');

    return this.prisma.event.update({
      where: { id: eventId },
      data: {
        ...(dto.title !== undefined && { title: dto.title }),
        ...(dto.description !== undefined && { description: dto.description }),
        ...(dto.location !== undefined && { location: dto.location }),
        ...(dto.startsAt !== undefined && { startsAt: new Date(dto.startsAt) }),
        ...(dto.endsAt !== undefined && { endsAt: new Date(dto.endsAt) }),
        ...(dto.isPublished !== undefined && { isPublished: dto.isPublished }),
      },
    });
  }

  async remove(tenantId: string, adminId: string, eventId: string) {
    const event = await this.prisma.event.findFirst({ where: { id: eventId, tenantId } });
    if (!event) throw new NotFoundException('Event not found');
    await this.prisma.event.delete({ where: { id: eventId } });

    await this.audit.log({
      tenantId,
      actorId: adminId,
      action: AuditAction.EVENT_DELETED,
      resourceType: 'Event',
      resourceId: eventId,
      payload: { deleted: true },
    });

    return { ok: true };
  }

  async getRsvps(tenantId: string, eventId: string) {
    const event = await this.prisma.event.findFirst({ where: { id: eventId, tenantId } });
    if (!event) throw new NotFoundException('Event not found');

    return this.prisma.eventRsvp.findMany({
      where: { eventId },
      include: { user: { select: { id: true, displayName: true, jid: true } } },
      orderBy: { createdAt: 'asc' },
    });
  }
}