pig-farm-controller/internal/infra/repository/pig_farm_repository.go

package repository

import (
	"errors"

	"git.huangwc.com/pig/pig-farm-controller/internal/infra/models"
	"gorm.io/gorm"
)

var (
	ErrHouseContainsPens = errors.New("cannot delete a pig house that still contains pens")
	ErrHouseNotFound     = errors.New("the specified pig house does not exist")
)

// PigFarmRepository 定义了与猪场资产（猪舍、猪栏）相关的数据库操作接口
type PigFarmRepository interface {
	// PigHouse methods
	CreatePigHouse(house *models.PigHouse) error
	GetPigHouseByID(id uint) (*models.PigHouse, error)
	ListPigHouses() ([]models.PigHouse, error)
	UpdatePigHouse(house *models.PigHouse) error
	DeletePigHouse(id uint) error

	// Pen methods
	CreatePen(pen *models.Pen) error
	GetPenByID(id uint) (*models.Pen, error)
	ListPens() ([]models.Pen, error)
	UpdatePen(pen *models.Pen) error
	DeletePen(id uint) error
}

// gormPigFarmRepository 是 PigFarmRepository 的 GORM 实现
type gormPigFarmRepository struct {
	db *gorm.DB
}

// NewGormPigFarmRepository 创建一个新的 PigFarmRepository GORM 实现实例
func NewGormPigFarmRepository(db *gorm.DB) PigFarmRepository {
	return &gormPigFarmRepository{db: db}
}

// --- PigHouse Implementation ---

func (r *gormPigFarmRepository) CreatePigHouse(house *models.PigHouse) error {
	return r.db.Create(house).Error
}

func (r *gormPigFarmRepository) GetPigHouseByID(id uint) (*models.PigHouse, error) {
	var house models.PigHouse
	if err := r.db.First(&house, id).Error; err != nil {
		return nil, err
	}
	return &house, nil
}

func (r *gormPigFarmRepository) ListPigHouses() ([]models.PigHouse, error) {
	var houses []models.PigHouse
	if err := r.db.Find(&houses).Error; err != nil {
		return nil, err
	}
	return houses, nil
}

func (r *gormPigFarmRepository) UpdatePigHouse(house *models.PigHouse) error {
	result := r.db.Model(&models.PigHouse{}).Where("id = ?", house.ID).Updates(house)
	if result.Error != nil {
		return result.Error
	}
	if result.RowsAffected == 0 {
		return gorm.ErrRecordNotFound
	}
	return nil
}

func (r *gormPigFarmRepository) DeletePigHouse(id uint) error {
	return r.db.Transaction(func(tx *gorm.DB) error {
		var penCount int64
		if err := tx.Model(&models.Pen{}).Where("house_id = ?", id).Count(&penCount).Error; err != nil {
			return err
		}
		if penCount > 0 {
			return ErrHouseContainsPens
		}

		result := tx.Delete(&models.PigHouse{}, id)
		if result.Error != nil {
			return result.Error
		}
		if result.RowsAffected == 0 {
			return gorm.ErrRecordNotFound
		}
		return nil
	})
}

// --- Pen Implementation ---

func (r *gormPigFarmRepository) CreatePen(pen *models.Pen) error {
	return r.db.Transaction(func(tx *gorm.DB) error {
		// 验证所属猪舍是否存在
		if err := tx.First(&models.PigHouse{}, pen.HouseID).Error; err != nil {
			if errors.Is(err, gorm.ErrRecordNotFound) {
				return ErrHouseNotFound
			}
			return err
		}
		return tx.Create(pen).Error
	})
}

func (r *gormPigFarmRepository) GetPenByID(id uint) (*models.Pen, error) {
	var pen models.Pen
	if err := r.db.First(&pen, id).Error; err != nil {
		return nil, err
	}
	return &pen, nil
}

func (r *gormPigFarmRepository) ListPens() ([]models.Pen, error) {
	var pens []models.Pen
	if err := r.db.Find(&pens).Error; err != nil {
		return nil, err
	}
	return pens, nil
}

func (r *gormPigFarmRepository) UpdatePen(pen *models.Pen) error {
	return r.db.Transaction(func(tx *gorm.DB) error {
		// 验证所属猪舍是否存在
		if err := tx.First(&models.PigHouse{}, pen.HouseID).Error; err != nil {
			if errors.Is(err, gorm.ErrRecordNotFound) {
				return ErrHouseNotFound
			}
			return err
		}

		result := tx.Model(&models.Pen{}).Where("id = ?", pen.ID).Updates(pen)
		if result.Error != nil {
			return result.Error
		}
		if result.RowsAffected == 0 {
			return gorm.ErrRecordNotFound
		}
		return nil
	})
}

func (r *gormPigFarmRepository) DeletePen(id uint) error {
	result := r.db.Delete(&models.Pen{}, id)
	if result.Error != nil {
		return result.Error
	}
	if result.RowsAffected == 0 {
		return gorm.ErrRecordNotFound
	}
	return nil
}