import { Injectable } from '@nestjs/common';
import { CreateFeedingPlanRequest } from '@/pet-feeder/dto/create-feeding-plan.request';
import { FeedingPlan } from '@/pet-feeder/entity/feeding-plan.entity';
import { InjectRepository } from '@nestjs/typeorm';
import { Repository } from 'typeorm';
import { FeedingPlanProduct } from '@/pet-feeder/entity/feeding-plan-product.entity';
import { PetService } from '@/pet-feeder/service/pet.service';
import { ProductService } from '@/pet-feeder/service/product.service';

@Injectable()
export class FeedingPlanService {
  constructor(
    @InjectRepository(FeedingPlan)
    private readonly feedingPlanRepository: Repository<FeedingPlan>,

    @InjectRepository(FeedingPlanProduct)
    private readonly feedingPlanProductRepository: Repository<FeedingPlanProduct>,

    private readonly petService: PetService,

    private readonly productService: ProductService,
  ) {}

  async create(
    createFeedingPlanRequest: CreateFeedingPlanRequest,
  ): Promise<FeedingPlan> {
    const feedingPlan = this.feedingPlanRepository.create({
      feedingGoal: createFeedingPlanRequest.feedingGoal,
      targetWeight: createFeedingPlanRequest.targetWeight,
    });
    feedingPlan.pet = await this.petService.get(createFeedingPlanRequest.petId);

    const feedingPlanProducts: FeedingPlanProduct[] = [];

    await Promise.all(
      createFeedingPlanRequest.products.map(async (product) => {
        const existProduct = await this.productService.get(product.id);
        const feedingPlanProduct = this.feedingPlanProductRepository.create({
          product: existProduct,
          dailyUsageWeight: product.dailyUsageWeight,
          percentage: product.percentage,
        });
        feedingPlanProducts.push(
          await this.feedingPlanProductRepository.save(feedingPlanProduct),
        );
      }),
    );
    feedingPlan.feedingPlanProducts = feedingPlanProducts;
    return this.feedingPlanRepository.save(feedingPlan);
  }

  async update(
    id: string,
    updateFeedingPlanRequest: CreateFeedingPlanRequest,
  ): Promise<FeedingPlan> {
    const feedingPlan = await this.get(id);
    feedingPlan.feedingGoal = updateFeedingPlanRequest.feedingGoal;
    feedingPlan.targetWeight = updateFeedingPlanRequest.targetWeight;
    const feedingPlanProducts: FeedingPlanProduct[] = [];

    await Promise.all(
      updateFeedingPlanRequest.products.map(async (product) => {
        const existProduct = await this.productService.get(product.id);
        const exitFeedingPlanProduct =
          await this.feedingPlanProductRepository.findOneBy({
            product: existProduct,
          });
        if (exitFeedingPlanProduct) {
          exitFeedingPlanProduct.dailyUsageWeight = product.dailyUsageWeight;
          exitFeedingPlanProduct.percentage = product.percentage;
          feedingPlanProducts.push(
            await this.feedingPlanProductRepository.save(
              exitFeedingPlanProduct,
            ),
          );
        } else {
          const feedingPlanProduct = this.feedingPlanProductRepository.create({
            product: existProduct,
            dailyUsageWeight: product.dailyUsageWeight,
            percentage: product.percentage,
          });
          feedingPlanProducts.push(
            await this.feedingPlanProductRepository.save(feedingPlanProduct),
          );
        }
      }),
    );
    return this.feedingPlanRepository.save(feedingPlan);
  }

  async get(id: string): Promise<FeedingPlan> {
    const feedingPlan = await this.feedingPlanRepository.findOneBy({ id });
    if (!feedingPlan) {
      throw new Error('Feeding plan not found');
    }
    return feedingPlan;
  }
}