import {
  ConflictException,
  Injectable,
  NotFoundException,
} from '@nestjs/common';
import { PrismaService } from '../prisma/prisma.service';
import { AuditLogService } from '../audit/audit-log.service';
import { Apiary, ApiaryStatus } from '../../generated/prisma';
import { CreateApiaryDto } from './dto/create-apiary.dto';
import { UpdateApiaryDto } from './dto/update-apiary.dto';

export interface ApiaryFilter {
  status?: ApiaryStatus;
  location?: string;
}

@Injectable()
export class ApiariesService {
  constructor(
    private readonly prisma: PrismaService,
    private readonly auditLog: AuditLogService,
  ) {}

  async findAll(filter: ApiaryFilter = {}): Promise<Apiary[]> {
    return this.prisma.apiary.findMany({
      where: {
        status: filter.status,
        location: filter.location
          ? { contains: filter.location, mode: 'insensitive' }
          : undefined,
      },
      orderBy: { name: 'asc' },
    });
  }

  async findById(id: string): Promise<Apiary> {
    const apiary = await this.prisma.apiary.findUnique({ where: { id } });
    if (!apiary) {
      throw new NotFoundException('Apiary not found');
    }
    return apiary;
  }

  async create(dto: CreateApiaryDto, actingUserId: string): Promise<Apiary> {
    const apiary = await this.prisma.apiary.create({ data: { ...dto } });
    await this.auditLog.record({
      entityType: 'Apiary',
      entityId: apiary.id,
      action: 'CREATE',
      userId: actingUserId,
      afterData: apiary,
    });
    return apiary;
  }

  async update(
    id: string,
    dto: UpdateApiaryDto,
    actingUserId: string,
  ): Promise<Apiary> {
    const before = await this.findById(id);
    const apiary = await this.prisma.apiary.update({
      where: { id },
      data: { ...dto },
    });
    await this.auditLog.record({
      entityType: 'Apiary',
      entityId: id,
      action: 'UPDATE',
      userId: actingUserId,
      beforeData: before,
      afterData: apiary,
    });
    return apiary;
  }

  async deactivate(id: string, actingUserId: string): Promise<Apiary> {
    const before = await this.findById(id);
    // Colony.apiaryId is a plain FK, not enforced against apiary status -
    // without this guard a colony can silently keep pointing at an
    // inactive apiary (still shows ACTIVE, still countable, but its
    // "location" has vanished from the active apiary list). Move the
    // colonies elsewhere or dissolve them first instead.
    const activeColonyCount = await this.prisma.colony.count({
      where: { apiaryId: id, status: 'ACTIVE' },
    });
    if (activeColonyCount > 0) {
      throw new ConflictException(
        `Der Bienenstand hat noch ${activeColonyCount} aktive(s) Volk/Völker - zuerst verlegen oder auflösen`,
      );
    }
    const apiary = await this.prisma.apiary.update({
      where: { id },
      data: { status: 'INACTIVE', deactivatedAt: new Date() },
    });
    await this.auditLog.record({
      entityType: 'Apiary',
      entityId: id,
      action: 'DEACTIVATE',
      userId: actingUserId,
      beforeData: before,
      afterData: apiary,
    });
    return apiary;
  }

  async reactivate(id: string, actingUserId: string): Promise<Apiary> {
    const before = await this.findById(id);
    if (before.status === 'ACTIVE') {
      throw new ConflictException('Apiary is already active');
    }
    const apiary = await this.prisma.apiary.update({
      where: { id },
      data: { status: 'ACTIVE', deactivatedAt: null },
    });
    await this.auditLog.record({
      entityType: 'Apiary',
      entityId: id,
      action: 'UPDATE',
      userId: actingUserId,
      beforeData: before,
      afterData: apiary,
    });
    return apiary;
  }
}