mh_goadmin_server/app/admin/models/category.go

package models

import (
	"fmt"
	"go-admin/app/admin/models/common"
	orm "go-admin/common/global"
	"go-admin/logger"
	"gorm.io/gorm"
)

type Category struct {
	Model

	Name                  string `json:"name"`                    // 分类名称
	Number                string `json:"number"`                  //编号
	Display               int8   `json:"display"`                 // 1 展示 0 隐藏
	Pid                   uint32 `json:"pid" gorm:"index"`        //父分类的编号
	CooperativeBusinessId uint32 `json:"cooperative_business_id"` //合作商id
}

var (
	Display   = 1
	UnDisplay = 0
)

func (c *Category) TableName() string {
	return "erp_category"
}

func (c *Category) BeforeCreate(tx *gorm.DB) error {
	if c.Number == "" {
		n, err := GenerateNumber(c.CooperativeBusinessId, c.Pid)
		if err != nil {
			logger.Error("before create category err", logger.Field("c", c), logger.Field("err", err))
			return err
		}
		c.Number = n
	}
	return nil
}

// GenerateNumber 生成分类编码
func GenerateNumber(cid uint32, pid uint32) (string, error) {
	var count int64
	var err error

	err = orm.Eloquent.Model(Category{}).
		Unscoped().
		Scopes(common.ScopeBusiness(cid)).
		Where("pid", pid).
		Count(&count).
		Error
	if err != nil {
		return "", err
	}
	if pid == 0 {
		return fmt.Sprintf("%03d", count+1), nil
	} else {
		var parent Category
		err = orm.Eloquent.Model(Category{}).
			Scopes(common.ScopeBusiness(cid)).
			Where("id", pid).
			First(&parent).Error
		if err != nil {
			return "", err
		}
		return fmt.Sprintf("%s%03d", parent.Number, count+1), nil
	}
}

// GetCategoryById 通过id获取分类
func GetCategoryById(id uint32) (*Category, error) {
	var c *Category
	err := orm.Eloquent.Model(c).Where("id", id).First(c).Error
	if err != nil {
		return nil, err
	}

	return c, nil
}

type CategoryModel struct {
	Category
	SubCategory []*CategoryModel
}

func ScopeOnlyDisplay(db *gorm.DB) *gorm.DB {
	return db.Where("display", Display)
}

// GetCategoryList 分类列表
func GetCategoryList(bid uint32, all bool) ([]*CategoryModel, error) {
	var list = make([]*CategoryModel, 0)
	m := orm.Eloquent.Model(Category{})

	var scopes = []func(db *gorm.DB) *gorm.DB{common.ScopeBusiness(bid)}
	if !all {
		scopes = append(scopes, ScopeOnlyDisplay)
	}

	err := m.Scopes(scopes...).Where("pid = ?", 0).Find(&list).Error
	if err != nil {
		return nil, err
	}
	for _, top := range list {
		top.SubCategory = findChildCategory(top, all)
	}

	return list, nil
}

// 查询子分类
func findChildCategory(prev *CategoryModel, all bool) []*CategoryModel {
	var cs []*CategoryModel
	m := orm.Eloquent.Model(Category{})
	if !all {
		m = m.Scopes(ScopeOnlyDisplay)
	}
	err := m.Where("pid", prev.ID).Find(&cs).Error
	if err != nil {
		return nil
	}

	for _, c := range cs {
		c.SubCategory = findChildCategory(c, all)
	}

	return cs
}