package service

import (
	"encoding/json"
	"fmt"
	"dianshang/internal/model"
	"dianshang/internal/repository"
)

type CommentService struct {
	commentRepo *repository.CommentRepository
	orderRepo   *repository.OrderRepository
	productRepo *repository.ProductRepository
}

func NewCommentService(commentRepo *repository.CommentRepository, orderRepo *repository.OrderRepository, productRepo *repository.ProductRepository) *CommentService {
	return &CommentService{
		commentRepo: commentRepo,
		orderRepo:   orderRepo,
		productRepo: productRepo,
	}
}

// CreateCommentRequest 创建评论请求
type CreateCommentRequest struct {
	OrderItemID uint     `json:"order_item_id" binding:"required"`
	Rating      int      `json:"rating" binding:"required,min=1,max=5"`
	Content     string   `json:"content"`
	Images      []string `json:"images"`
	IsAnonymous bool     `json:"is_anonymous"`
}

// CreateComment 创建评论
func (s *CommentService) CreateComment(userID uint, req *CreateCommentRequest) (*model.Comment, error) {
	// 1. 验证订单项是否存在且属于该用户
	orderItem, err := s.orderRepo.GetOrderItemByID(req.OrderItemID)
	if err != nil {
		return nil, fmt.Errorf("订单项不存在")
	}

	// 获取订单信息验证用户权限
	order, err := s.orderRepo.GetByID(orderItem.OrderID)
	if err != nil {
		return nil, fmt.Errorf("订单不存在")
	}

	if order.UserID != userID {
		return nil, fmt.Errorf("无权限评论此商品")
	}

	// 2. 验证订单状态（只有已完成的订单才能评论）
	if order.Status != model.OrderStatusCompleted {
		return nil, fmt.Errorf("订单未完成，无法评论")
	}

	// 3. 检查是否已经评论过
	if orderItem.IsCommented {
		return nil, fmt.Errorf("该商品已经评论过了")
	}

	// 4. 处理图片数据
	var imagesJSON string
	if len(req.Images) > 0 {
		imagesBytes, _ := json.Marshal(req.Images)
		imagesJSON = string(imagesBytes)
	}

	// 5. 创建评论
	comment := &model.Comment{
		UserID:      userID,
		ProductID:   orderItem.ProductID,
		OrderID:     orderItem.OrderID,
		OrderItemID: req.OrderItemID,
		Rating:      req.Rating,
		Content:     req.Content,
		Images:      imagesJSON,
		IsAnonymous: req.IsAnonymous,
		Status:      1,
	}

	if err := s.commentRepo.Create(comment); err != nil {
		return nil, fmt.Errorf("创建评论失败: %v", err)
	}

	// 6. 更新订单项评论状态
	orderItem.IsCommented = true
	if err := s.orderRepo.SaveOrderItem(orderItem); err != nil {
		return nil, fmt.Errorf("更新订单项状态失败: %v", err)
	}

	// 7. 更新商品评论统计
	if err := s.commentRepo.UpdateProductStats(orderItem.ProductID); err != nil {
		return nil, fmt.Errorf("更新商品统计失败: %v", err)
	}

	return comment, nil
}

// GetProductComments 获取商品评论列表
func (s *CommentService) GetProductComments(productID uint, page, pageSize int, rating int) ([]model.Comment, int64, error) {
	offset := (page - 1) * pageSize
	return s.commentRepo.GetByProductID(productID, offset, pageSize, rating)
}

// GetUserComments 获取用户评论列表
func (s *CommentService) GetUserComments(userID uint, page, pageSize int) ([]model.Comment, int64, error) {
	offset := (page - 1) * pageSize
	return s.commentRepo.GetByUserID(userID, offset, pageSize)
}

// GetCommentStats 获取商品评论统计
func (s *CommentService) GetCommentStats(productID uint) (*model.CommentStats, error) {
	return s.commentRepo.GetStats(productID)
}

// GetHighRatingComments 获取高分评论（用于首页展示）
func (s *CommentService) GetHighRatingComments(limit int) ([]model.Comment, error) {
	if limit <= 0 || limit > 50 {
		limit = 6 // 默认6条
	}
	// 获取评分>=4的高分评论
	return s.commentRepo.GetHighRatingComments(limit, 4)
}

// GetCommentByID 获取评论详情
func (s *CommentService) GetCommentByID(id uint) (*model.Comment, error) {
	return s.commentRepo.GetByID(id)
}

// CreateReplyRequest 创建回复请求
type CreateReplyRequest struct {
	CommentID uint   `json:"comment_id" binding:"required"`
	Content   string `json:"content" binding:"required"`
}

// CreateReply 创建评论回复
func (s *CommentService) CreateReply(userID uint, req *CreateReplyRequest, isAdmin bool) (*model.CommentReply, error) {
	// 验证评论是否存在
	comment, err := s.commentRepo.GetByID(req.CommentID)
	if err != nil {
		return nil, fmt.Errorf("评论不存在")
	}

	if comment.Status != 1 {
		return nil, fmt.Errorf("评论状态异常，无法回复")
	}

	// 创建回复
	reply := &model.CommentReply{
		CommentID: req.CommentID,
		UserID:    userID,
		Content:   req.Content,
		IsAdmin:   isAdmin,
		Status:    1,
	}

	if err := s.commentRepo.CreateReply(reply); err != nil {
		return nil, fmt.Errorf("创建回复失败: %v", err)
	}

	return reply, nil
}

// LikeComment 点赞评论
func (s *CommentService) LikeComment(commentID, userID uint) error {
	return s.commentRepo.LikeComment(commentID, userID)
}

// UnlikeComment 取消点赞评论
func (s *CommentService) UnlikeComment(commentID, userID uint) error {
	return s.commentRepo.UnlikeComment(commentID, userID)
}

// GetCommentList 获取评论列表（管理端）
func (s *CommentService) GetCommentList(page, pageSize int, conditions map[string]interface{}) ([]model.Comment, int64, error) {
	offset := (page - 1) * pageSize
	return s.commentRepo.GetList(offset, pageSize, conditions)
}

// UpdateCommentStatus 更新评论状态（管理端）
func (s *CommentService) UpdateCommentStatus(id uint, status int) error {
	comment, err := s.commentRepo.GetByID(id)
	if err != nil {
		return fmt.Errorf("评论不存在")
	}

	comment.Status = status
	if err := s.commentRepo.Update(comment); err != nil {
		return fmt.Errorf("更新评论状态失败: %v", err)
	}

	// 如果是隐藏或删除评论，需要更新商品统计
	if status != 1 {
		if err := s.commentRepo.UpdateProductStats(comment.ProductID); err != nil {
			return fmt.Errorf("更新商品统计失败: %v", err)
		}
	}

	return nil
}

// DeleteComment 删除评论（管理端）
func (s *CommentService) DeleteComment(id uint) error {
	return s.UpdateCommentStatus(id, 3)
}

// GetUncommentedOrderItems 获取用户未评论的订单项
func (s *CommentService) GetUncommentedOrderItems(userID uint) ([]model.OrderItem, error) {
	// 获取用户已完成但未评论的订单项
	return s.orderRepo.GetUncommentedOrderItems(userID)
}