import { Injectable, NotFoundException } from '@nestjs/common';
import type { ResourceBizType, ResourceMediaType, ResourceOwnerType } from '@prisma/client';
import { Prisma } from '@prisma/client';
import { randomUUID } from 'crypto';
import { PrismaService } from '../../common/prisma/prisma.module';
import { serializeBigInt } from '../../common/decorators/current-user.decorator';
import type { ResourceListQueryDto } from './dto/common-query.dto';
import type { RegisterResourceDto, UpdateResourceDto, UploadTokenDto } from './dto/common-mutate.dto';

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

  getUploadToken(dto: UploadTokenDto) {
    const bucket = process.env.OSS_BUCKET || 'mock-dukang';
    const ext = dto.fileName.includes('.') ? dto.fileName.split('.').pop() : 'bin';
    const key = `uploads/${dto.bizType.toLowerCase()}/${Date.now()}-${randomUUID().slice(0, 8)}.${ext}`;
    const cdnBase = process.env.OSS_CDN_BASE || 'https://mock-cdn.dukang.local';
    return {
      bucket,
      region: process.env.OSS_REGION || 'oss-cn-hangzhou',
      ossKey: key,
      url: `${cdnBase}/${key}`,
      mock: true,
      expireAt: new Date(Date.now() + 15 * 60 * 1000).toISOString(),
      mediaType: dto.mediaType,
      bizType: dto.bizType,
    };
  }

  async register(dto: RegisterResourceDto) {
    const resource = await this.prisma.commonResource.create({
      data: {
        ownerType: dto.ownerType as ResourceOwnerType,
        ownerId: BigInt(dto.ownerId),
        bizType: dto.bizType as ResourceBizType,
        mediaType: dto.mediaType as ResourceMediaType,
        ossBucket: dto.ossBucket ?? process.env.OSS_BUCKET ?? 'mock-dukang',
        ossKey: dto.ossKey,
        url: dto.url,
        fileName: dto.fileName,
        sortOrder: dto.sortOrder ?? 0,
      },
    });
    return serializeBigInt(resource);
  }

  async list(query: ResourceListQueryDto) {
    const page = query.page ?? 1;
    const pageSize = query.pageSize ?? 20;
    const where: Prisma.CommonResourceWhereInput = {
      status: (query.status ?? 'ACTIVE') as Prisma.EnumResourceStatusFilter['equals'],
    };
    if (query.ownerType) where.ownerType = query.ownerType as Prisma.EnumResourceOwnerTypeFilter['equals'];
    if (query.ownerId) where.ownerId = BigInt(query.ownerId);
    if (query.bizType) where.bizType = query.bizType as Prisma.EnumResourceBizTypeFilter['equals'];

    const [items, total] = await Promise.all([
      this.prisma.commonResource.findMany({
        where,
        orderBy: [{ sortOrder: 'asc' }, { createdAt: 'desc' }],
        skip: (page - 1) * pageSize,
        take: pageSize,
      }),
      this.prisma.commonResource.count({ where }),
    ]);
    return serializeBigInt({ items, total, page, pageSize });
  }

  async detail(id: bigint) {
    const resource = await this.prisma.commonResource.findUnique({ where: { id } });
    if (!resource) throw new NotFoundException('资源不存在');
    return serializeBigInt(resource);
  }

  async update(id: bigint, dto: UpdateResourceDto) {
    await this.detail(id);
    const resource = await this.prisma.commonResource.update({
      where: { id },
      data: {
        ...(dto.url !== undefined ? { url: dto.url, ossKey: dto.url } : {}),
        ...(dto.mediaType !== undefined ? { mediaType: dto.mediaType as 'IMAGE' | 'VIDEO' | 'FILE' } : {}),
        ...(dto.sortOrder !== undefined ? { sortOrder: dto.sortOrder } : {}),
        ...(dto.status !== undefined ? { status: dto.status as 'ACTIVE' | 'DELETED' } : {}),
      },
    });
    return serializeBigInt(resource);
  }

  async remove(id: bigint) {
    await this.detail(id);
    await this.prisma.commonResource.update({
      where: { id },
      data: { status: 'DELETED' },
    });
    return { ok: true };
  }
}