package usecase

import (
	"errors"
	"time"
	"users_management/m/model/dto/req"
	"users_management/m/model/entity"
	"users_management/m/repository"

	"github.com/go-playground/validator/v10"
	"github.com/google/uuid"
)

type FishboneUseCase interface {
	CreateFishbone(fishbone req.FishboneDTO) error
	GetAllFishbone() ([]entity.Fishbone, error)
	GetByID(id uuid.UUID) (entity.Fishbone, error)

	UpdateFishbone(id uuid.UUID, fishbone req.UpdateFishboneDTO) error
}

type fishboneUsecase struct {
	fishboneRepo repository.FishboneRepo
	validate *validator.Validate
}

func NewFishboneUseCase(fishboneRepo repository.FishboneRepo) FishboneUseCase {
	return &fishboneUsecase{
		fishboneRepo: fishboneRepo,
		validate: validator.New(),
	}
}

func (u *fishboneUsecase) CreateFishbone(fishbone req.FishboneDTO) error {
	err := u.validate.Struct(fishbone)
	if err != nil {
		return err
	}

	newFishbone := entity.Fishbone{
		ID: uuid.New(),
		BackboneID: fishbone.BackboneID,
		DeviceStartID: fishbone.DeviceStartID,
		DeviceEndID: fishbone.DeviceEndID,
		CoreAmount: fishbone.CoreAmount,
		CreatedAt: time.Now(),
		UpdatedAt: time.Now(),
	}

	return u.fishboneRepo.Post(newFishbone)
}

func (u *fishboneUsecase) GetAllFishbone() ([]entity.Fishbone, error) {
	fishbones, err := u.fishboneRepo.GetAll()
	if err != nil {
		return fishbones, err
	}
	return fishbones, nil
}

func (u *fishboneUsecase) GetByID(id uuid.UUID) (entity.Fishbone, error) {
	fishbone, err := u.fishboneRepo.GetByID(id)
	if err != nil {
		return fishbone, err
	}
	return fishbone, nil
}

func (u *fishboneUsecase) UpdateFishbone(id uuid.UUID, fishbone req.UpdateFishboneDTO) error {
	err := u.validate.Struct(fishbone)
	if err != nil {
		return err
	}

	updates := make(map[string]interface{})

	if fishbone.BackboneID != nil {
		updates["BackboneID"] = *fishbone.BackboneID
	}
	if fishbone.DeviceStartID != nil {
		updates["DeviceStartID"] = *fishbone.DeviceStartID
	}
	if fishbone.DeviceEndID != nil {
		updates["DeviceEndID"] = *fishbone.DeviceEndID
	}
	if fishbone.CoreAmount != nil {
		updates["CoreAmount"] = *fishbone.CoreAmount
	}
	if len(updates) == 0 {
		return errors.New("no fields to update")
	}
	
	updates["UpdatedAt"] = time.Now()

	return u.fishboneRepo.Update(id, updates)
}