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

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

  async getCategories(query: any) {
    const { page = 1, limit = 10, search = '' } = query;
    const skip = (Number(page) - 1) * Number(limit);
    
    const where = search ? { name: { contains: search, mode: 'insensitive' as any } } : {};
    
    const [data, total] = await Promise.all([
      this.prisma.category.findMany({
        where,
        skip,
        take: Number(limit),
        orderBy: { createdAt: 'desc' }
      }),
      this.prisma.category.count({ where })
    ]);

    return {
      data,
      meta: { total, page: Number(page), limit: Number(limit), lastPage: Math.ceil(total / Number(limit)) }
    };
  }

  async getAllCategoriesRaw() {
    return this.prisma.category.findMany({ orderBy: { name: 'asc' } });
  }

  async createCategory(data: any) {
    const cleanData = { ...data };
    Object.keys(cleanData).forEach(k => {
      if (cleanData[k] === '') cleanData[k] = null;
    });
    // Ensure required fields
    if (!cleanData.slug) cleanData.slug = cleanData.name.replace(/\s+/g, '-').toLowerCase();
    
    return this.prisma.category.create({ data: cleanData });
  }

  async updateCategory(id: string, data: any) {
    const category = await this.prisma.category.findUnique({ where: { id } });
    if (!category) throw new NotFoundException('Category not found');
    
    const cleanData = { ...data };
    Object.keys(cleanData).forEach(k => {
      if (cleanData[k] === '') cleanData[k] = null;
    });

    return this.prisma.category.update({ where: { id }, data: cleanData });
  }

  async deleteCategory(id: string) {
    const category = await this.prisma.category.findUnique({ where: { id } });
    if (!category) throw new NotFoundException('Category not found');
    return this.prisma.category.delete({ where: { id } });
  }
}