import { Injectable } from '@nestjs/common'
import { isEmpty, isNil, sample } from 'lodash'

import { FoodPlanRepository, MenuRepository, PatientRepository } from '../../../repositories'
import { UserNotFoundError } from '../../../errors/user_not_found.error'
import { FoodPlanAIService } from '../../../services'
import { Menu, Patient } from '../../../models'

@Injectable()
export class Nutrition {
  constructor(
    private readonly patientRepository: PatientRepository,
    private readonly menuRepository: MenuRepository,
    private readonly foodPlanRepository: FoodPlanRepository,
    private readonly foodPlanAiService: FoodPlanAIService,
  ) {}

  async generateMenuToPatient(patientId: string): Promise<string> {
    const patient = await this.patientRepository.get(patientId)

    if (!patient) throw new UserNotFoundError(`id: ${patientId}`)

    patient.menu_id = await this.getPatientNewMenuId(patient)

    await this.patientRepository.update(patient)

    return patient.menu_id
  }

  private async getPatientNewMenuId(patient: Patient): Promise<string> {
    let menu = await this.getPredictedMenuFromPatientId(patient)

    if (!isNil(menu)) return await this.menuRepository.createWithRelationships(menu)

    menu = await this.getRandomMenu(patient)

    return menu?.id
  }

  private async getPredictedMenuFromPatientId(patient: Patient): Promise<Menu> {
    const predictedMenu = await this.foodPlanAiService.getFromPatientId(patient.id)

    if (!predictedMenu?.food_plan_id) return null

    const originalFoodPlan = await this.foodPlanRepository.getWithRelationships(predictedMenu.food_plan_id)

    if (!originalFoodPlan) {
      console.warn("Predicted food plan doesn't exists", predictedMenu.food_plan_id)

      return null
    }

    const menu = originalFoodPlan.cloneToMenu(true)

    menu.changeMealGroupTimes(predictedMenu.meal_time_adjusted, true)

    return menu
  }

  private async getRandomMenu(patient: Patient): Promise<Menu> {
    const menus = await this.menuRepository.findBy(patient.goal_id, patient.restriction_ids)

    if (isEmpty(menus)) return null

    return sample<Menu>(menus)
  }
}