package service

import (
	"github.com/freefire/jiang13-bbs/model"
	"gorm.io/gorm"
)

// BoardService 板块服务
type BoardService struct {
	db *gorm.DB
}

func NewBoardService(db *gorm.DB) *BoardService {
	return &BoardService{db: db}
}

// BoardWithCount 板块及其已发布帖子计数（Board 字段被 encoding/json 展平）
type BoardWithCount struct {
	model.Board
	PostCount int64 `json:"post_count"`
}

// List 获取所有板块（按 sort_order 排序），附带各板块已发布帖子数（板块目录页展示用）
func (s *BoardService) List() ([]BoardWithCount, error) {
	var boards []model.Board
	if err := s.db.Order("sort_order ASC, id ASC").Find(&boards).Error; err != nil {
		return nil, err
	}
	type countRow struct {
		BoardID uint
		Cnt     int64
	}
	var counts []countRow
	if err := s.db.Model(&model.Post{}).
		Select("board_id, COUNT(*) AS cnt").
		Where("status = ?", model.ContentStatusPublished).
		Group("board_id").Scan(&counts).Error; err != nil {
		return nil, err
	}
	countMap := make(map[uint]int64, len(counts))
	for _, c := range counts {
		countMap[c.BoardID] = c.Cnt
	}
	items := make([]BoardWithCount, 0, len(boards))
	for _, b := range boards {
		items = append(items, BoardWithCount{Board: b, PostCount: countMap[b.ID]})
	}
	return items, nil
}

// Get 根据 ID 获取板块
func (s *BoardService) Get(id uint) (*model.Board, error) {
	var board model.Board
	if err := s.db.First(&board, id).Error; err != nil {
		return nil, err
	}
	return &board, nil
}