package admin

import (
	"context"
	"server/internal/db"
	"server/internal/db/sqlc"
	"server/internal/model/common"
	"server/internal/model/request"
	"server/internal/pkg/dberr"
	"server/internal/pkg/errs"
)

type CategoryService struct {
	store *db.Store
}

func NewCategoryService(store *db.Store) *CategoryService {
	return &CategoryService{
		store: store,
	}
}

func (s *CategoryService) List(ctx context.Context, p *common.Pagination) (*common.PageResult[sqlc.Category], error) {
	params := sqlc.ListCategoriesParams{
		Limit:  p.PageSize,
		Offset: (p.Page - 1) * p.PageSize,
	}

	total, err := s.store.CountCategories(ctx)
	if err != nil {
		return nil, err
	}

	list, err := s.store.ListCategories(ctx, params)
	if err != nil {
		return nil, err
	}

	return &common.PageResult[sqlc.Category]{
		List:  list,
		Total: total,
	}, nil
}

func (s *CategoryService) ListAll(ctx context.Context) ([]sqlc.Category, error) {
	return s.store.ListAllCategories(ctx)
}

func (s *CategoryService) Create(ctx context.Context, req request.CreateCategoryRequest) error {
	params := sqlc.CreateCategoryParams{
		Name: req.Name,
		Code: req.Code,
		Sort: req.Sort,
	}

	err := s.store.CreateCategory(ctx, params)
	return dberr.MapUniqueViolation(err, dberr.CategoryCodeKey, errs.ErrCategoryCodeAlreadyExists)
}

func (s *CategoryService) Update(ctx context.Context, id int32, req request.UpdateCategoryRequest) error {
	params := sqlc.UpdateCategoryParams{
		ID:   id,
		Name: req.Name,
		Code: req.Code,
		Sort: req.Sort,
	}
	rows, err := s.store.UpdateCategory(ctx, params)
	// 先判断数据条目是否存在
	if err = dberr.MapRowsAffected(rows, err, errs.ErrCategoryNotFound); err != nil {
		// 再判断code是否重复
		return dberr.MapUniqueViolation(err, dberr.CategoryCodeKey, errs.ErrCategoryCodeAlreadyExists)
	}

	return nil
}

func (s *CategoryService) Delete(ctx context.Context, id int32) error {
	return s.store.WithTx(ctx, func(q *sqlc.Queries) error {
		err := q.DeletePostCategoryByCategoryID(ctx, id)
		if err != nil {
			return err
		}

		rows, err := q.DeleteCategory(ctx, id)
		return dberr.MapRowsAffected(rows, err, errs.ErrCategoryNotFound)
	})
}