package category

import (
	"context"
	"database/sql"
	"time"

	"photography-backend/internal/model"
	"photography-backend/internal/svc"
	"photography-backend/internal/types"
	"photography-backend/pkg/errorx"

	"github.com/zeromicro/go-zero/core/logx"
)

type UpdateCategoryLogic struct {
	logx.Logger
	ctx    context.Context
	svcCtx *svc.ServiceContext
}

// 更新分类
func NewUpdateCategoryLogic(ctx context.Context, svcCtx *svc.ServiceContext) *UpdateCategoryLogic {
	return &UpdateCategoryLogic{
		Logger: logx.WithContext(ctx),
		ctx:    ctx,
		svcCtx: svcCtx,
	}
}

func (l *UpdateCategoryLogic) UpdateCategory(req *types.UpdateCategoryRequest) (resp *types.UpdateCategoryResponse, err error) {
	// 1. 参数验证
	if req.Name == "" && req.Description == "" {
		return nil, errorx.NewWithCode(errorx.InvalidParameter)
	}

	// 2. 查询分类是否存在
	category, err := l.svcCtx.CategoryModel.FindOne(l.ctx, req.Id)
	if err != nil {
		if err == model.ErrNotFound {
			return nil, errorx.NewWithCode(errorx.CategoryNotFound)
		}
		logx.Errorf("查询分类失败: %v", err)
		return nil, errorx.NewWithCode(errorx.ServerError)
	}

	// 3. 检查名称是否重复 (如果要更新名称)
	if req.Name != "" && req.Name != category.Name {
		existingCategory, err := l.svcCtx.CategoryModel.FindOneByName(l.ctx, req.Name)
		if err != nil && err != model.ErrNotFound {
			logx.Errorf("查询分类名称失败: %v", err)
			return nil, errorx.NewWithCode(errorx.ServerError)
		}
		if existingCategory != nil {
			return nil, errorx.NewWithCode(errorx.CategoryExists)
		}
	}

	// 4. 更新分类信息
	if req.Name != "" {
		category.Name = req.Name
	}
	if req.Description != "" {
		category.Description = sql.NullString{String: req.Description, Valid: true}
	}
	category.UpdatedAt = time.Now()

	// 5. 保存到数据库
	err = l.svcCtx.CategoryModel.Update(l.ctx, category)
	if err != nil {
		logx.Errorf("更新分类失败: %v", err)
		return nil, errorx.NewWithCode(errorx.ServerError)
	}

	// 6. 构造响应
	return &types.UpdateCategoryResponse{
		BaseResponse: types.BaseResponse{
			Code:    errorx.Success,
			Message: "分类更新成功",
		},
		Data: types.Category{
			Id:          category.Id,
			Name:        category.Name,
			Description: category.Description.String,
			CreatedAt:   category.CreatedAt.Unix(),
			UpdatedAt:   category.UpdatedAt.Unix(),
		},
	}, nil
}