import { BadRequestException, Injectable } from '@nestjs/common';
import { BaseCrudService } from '../common/base-crud.service.js';
import { PrismaService } from '../prisma/prisma.service.js';
import { getRequestContext } from '../common/context/request-context.js';
import { CreateOrgDto, UpdateOrgDto } from './dto.js';

@Injectable()
export class OrgsService extends BaseCrudService {
  constructor(prisma: PrismaService) {
    super(prisma, 'org');
  }

  /** 组织树列表：按数据权限过滤（空 orgCodes=全部可见）。 */
  listOrgs() {
    const ctx = getRequestContext();
    const where: Record<string, unknown> = {};
    if (ctx && ctx.orgCodes.length > 0) {
      where.code = { in: ctx.orgCodes };
    }
    return this.list(where, { sort: 'asc' });
  }

  async createOrg(dto: CreateOrgDto) {
    await this.assertValidParent(dto.parentCode);
    return this.create({ ...dto });
  }

  async updateOrg(id: string, dto: UpdateOrgDto) {
    if (dto.parentCode !== undefined) {
      const current = await this.findById(id);
      await this.assertValidParent(dto.parentCode, current?.code);
    }
    return this.update(id, { ...dto });
  }

  /** 批量删除组织（软删 + 回收 code），收集失败项。 */
  async batchDelete(ids: string[]) {
    const failed: string[] = [];
    for (const id of ids) {
      try {
        await this.softRemove(id);
      } catch {
        failed.push(id);
      }
    }
    return { total: ids.length, success: ids.length - failed.length, failed };
  }

  /** 校验父组织存在，且不会构成环（父不能是自身或自身后代）。 */
  private async assertValidParent(parentCode: string | null | undefined, selfCode?: string): Promise<void> {
    if (!parentCode) return; // 根节点
    const parent = await this.db().findFirst({ where: { code: parentCode } });
    if (!parent) throw new BadRequestException('父组织不存在');
    if (!selfCode) return;
    let cur: string | null = parentCode;
    const visited = new Set<string>();
    while (cur && !visited.has(cur)) {
      if (cur === selfCode) throw new BadRequestException('不能将组织挂到自身或其子组织下');
      visited.add(cur);
      const node: { parentCode: string | null } | null = await this.db().findFirst({
        where: { code: cur },
        select: { parentCode: true },
      });
      cur = node?.parentCode ?? null;
    }
  }
}