import { PrismaService } from '../prisma/prisma.service.js';
import { getRequestContext } from './context/request-context.js';

/**
 * 软删时需「改名回收」唯一键的模型映射：modelName → 唯一字段及其列长。
 * 目的：软删只置 deletedAt 不释放 @@unique，重建同名会 P2002；删除时把唯一字段改名
 * 成「原值(截断) + #id」释放唯一键，展示名字段（name/label）保持不变。
 */
const RECYCLE_FIELDS: Record<string, { field: string; maxLen: number }> = {
  user: { field: 'username', maxLen: 64 },
  role: { field: 'code', maxLen: 64 },
  resource: { field: 'code', maxLen: 128 },
  org: { field: 'code', maxLen: 64 },
  dictType: { field: 'code', maxLen: 64 },
  dictItem: { field: 'value', maxLen: 64 },
  config: { field: 'key', maxLen: 128 },
};

/**
 * 通用 CRUD 基类：封装分页/创建/更新/软删。
 * 创建时自动注入 tenantCode（Tenant 模型除外）；软删由子类按需调用 softRemove。
 */
export class BaseCrudService {
  constructor(
    protected readonly prisma: PrismaService,
    private readonly modelName: string,
  ) {}

  protected db(): any {
    return (this.prisma.client as any)[this.modelName];
  }

  async paginate(
    page = 1,
    pageSize = 20,
    where: Record<string, unknown> = {},
    orderBy: Record<string, unknown> = { createdAt: 'desc' },
  ) {
    const [list, total] = await Promise.all([
      this.db().findMany({ where, skip: (page - 1) * pageSize, take: pageSize, orderBy }),
      this.db().count({ where }),
    ]);
    return { list, total, page, pageSize };
  }

  async list(where: Record<string, unknown> = {}, orderBy?: Record<string, unknown>) {
    return this.db().findMany({ where, orderBy });
  }

  async findById(id: string) {
    return this.db().findUnique({ where: { id } });
  }

  async create(data: Record<string, unknown>) {
    const ctx = getRequestContext();
    if (ctx && this.modelName !== 'Tenant') data.tenantCode = ctx.tenantCode;
    return this.db().create({ data });
  }

  async update(id: string, data: Record<string, unknown>) {
    return this.db().update({ where: { id }, data });
  }

  async softRemove(id: string) {
    const recycle = RECYCLE_FIELDS[this.modelName];
    if (!recycle) {
      return this.db().update({ where: { id }, data: { deletedAt: new Date() } });
    }
    // 先读原值，改名回收唯一键，再软删
    const record = await this.findById(id);
    const original = record?.[recycle.field];
    if (original == null) {
      return this.db().update({ where: { id }, data: { deletedAt: new Date() } });
    }
    const suffix = `#${id}`;
    const recycled = `${String(original).slice(0, recycle.maxLen - suffix.length)}${suffix}`;
    return this.db().update({ where: { id }, data: { [recycle.field]: recycled, deletedAt: new Date() } });
  }
}