package service

import (
	"context"
	"encoding/json"

	"carrot_bbs/internal/dto"
	"carrot_bbs/internal/model"
	"carrot_bbs/internal/repository"
)

// AdminCommentService 管理端评论服务接口
type AdminCommentService interface {
	GetCommentList(ctx context.Context, page, pageSize int, keyword, postID, authorID, status, startDate, endDate string) ([]dto.AdminCommentListResponse, int64, error)
	GetCommentDetail(ctx context.Context, commentID string) (*dto.AdminCommentDetailResponse, error)
	DeleteComment(ctx context.Context, commentID string) error
	BatchDeleteComments(ctx context.Context, ids []string) (*dto.AdminBatchOperationResponse, error)
	ModerateComment(ctx context.Context, commentID string, status model.CommentStatus, reason, reviewedBy string) (*dto.AdminCommentDetailResponse, error)
	BatchModerateComments(ctx context.Context, ids []string, status model.CommentStatus, reviewedBy string) (*dto.AdminBatchOperationResponse, error)
	GetCommentsByPostID(ctx context.Context, postID string, page, pageSize int) ([]dto.AdminCommentListResponse, int64, error)
}

// adminCommentServiceImpl 管理端评论服务实现
type adminCommentServiceImpl struct {
	commentRepo repository.CommentRepository
	postRepo    repository.PostRepository
}

// NewAdminCommentService 创建管理端评论服务
func NewAdminCommentService(commentRepo repository.CommentRepository, postRepo repository.PostRepository) AdminCommentService {
	return &adminCommentServiceImpl{
		commentRepo: commentRepo,
		postRepo:    postRepo,
	}
}

// GetCommentList 获取评论列表
func (s *adminCommentServiceImpl) GetCommentList(ctx context.Context, page, pageSize int, keyword, postID, authorID, status, startDate, endDate string) ([]dto.AdminCommentListResponse, int64, error) {
	filter := repository.AdminCommentListFilter{
		Keyword:   keyword,
		PostID:    postID,
		AuthorID:  authorID,
		Status:    status,
		StartDate: startDate,
		EndDate:   endDate,
		Page:      page,
		PageSize:  pageSize,
	}

	comments, total, err := s.commentRepo.GetAdminCommentList(filter)
	if err != nil {
		return nil, 0, err
	}

	responses := make([]dto.AdminCommentListResponse, len(comments))
	for i, comment := range comments {
		responses[i] = s.convertCommentToAdminListResponse(comment)
	}

	return responses, total, nil
}

// GetCommentDetail 获取评论详情
func (s *adminCommentServiceImpl) GetCommentDetail(ctx context.Context, commentID string) (*dto.AdminCommentDetailResponse, error) {
	comment, err := s.commentRepo.GetAdminCommentByID(commentID)
	if err != nil {
		return nil, err
	}

	return s.convertCommentToAdminDetailResponse(comment), nil
}

// DeleteComment 删除评论
func (s *adminCommentServiceImpl) DeleteComment(ctx context.Context, commentID string) error {
	return s.commentRepo.Delete(commentID)
}

// BatchDeleteComments 批量删除评论
func (s *adminCommentServiceImpl) BatchDeleteComments(ctx context.Context, ids []string) (*dto.AdminBatchOperationResponse, error) {
	failedIDs, err := s.commentRepo.BatchDelete(ids)
	if err != nil {
		return &dto.AdminBatchOperationResponse{
			Success: false,
			Message: "批量删除失败",
			Failed:  ids,
		}, err
	}

	if len(failedIDs) == 0 {
		return &dto.AdminBatchOperationResponse{
			Success: true,
			Message: "批量删除成功",
		}, nil
	}

	return &dto.AdminBatchOperationResponse{
		Success: true,
		Message: "部分评论删除成功",
		Failed:  failedIDs,
	}, nil
}

func (s *adminCommentServiceImpl) ModerateComment(ctx context.Context, commentID string, status model.CommentStatus, reason, reviewedBy string) (*dto.AdminCommentDetailResponse, error) {
	_, err := s.commentRepo.GetAdminCommentByID(commentID)
	if err != nil {
		return nil, err
	}

	if err := s.commentRepo.UpdateModerationStatus(commentID, status, reason, reviewedBy); err != nil {
		return nil, err
	}

	comment, err := s.commentRepo.GetAdminCommentByID(commentID)
	if err != nil {
		return nil, err
	}

	return s.convertCommentToAdminDetailResponse(comment), nil
}

func (s *adminCommentServiceImpl) BatchModerateComments(ctx context.Context, ids []string, status model.CommentStatus, reviewedBy string) (*dto.AdminBatchOperationResponse, error) {
	var failedIDs []string
	for _, id := range ids {
		if err := s.commentRepo.UpdateModerationStatus(id, status, "", reviewedBy); err != nil {
			failedIDs = append(failedIDs, id)
		}
	}

	if len(failedIDs) == 0 {
		return &dto.AdminBatchOperationResponse{
			Success: true,
			Message: "批量审核成功",
		}, nil
	}

	if len(failedIDs) == len(ids) {
		return &dto.AdminBatchOperationResponse{
			Success: false,
			Message: "批量审核失败",
			Failed:  failedIDs,
		}, nil
	}

	return &dto.AdminBatchOperationResponse{
		Success: true,
		Message: "部分评论审核成功",
		Failed:  failedIDs,
	}, nil
}

// GetCommentsByPostID 获取帖子的评论列表
func (s *adminCommentServiceImpl) GetCommentsByPostID(ctx context.Context, postID string, page, pageSize int) ([]dto.AdminCommentListResponse, int64, error) {
	comments, total, err := s.commentRepo.GetCommentsByPostIDForAdmin(postID, page, pageSize)
	if err != nil {
		return nil, 0, err
	}

	responses := make([]dto.AdminCommentListResponse, len(comments))
	for i, comment := range comments {
		responses[i] = s.convertCommentToAdminListResponse(comment)
	}

	return responses, total, nil
}

// convertCommentToAdminListResponse 转换评论为管理端列表响应
func (s *adminCommentServiceImpl) convertCommentToAdminListResponse(comment *model.Comment) dto.AdminCommentListResponse {
	// 解析图片
	var images []dto.CommentImageResponse
	if comment.Images != "" {
		var urls []string
		if err := json.Unmarshal([]byte(comment.Images), &urls); err == nil {
			images = make([]dto.CommentImageResponse, len(urls))
			for i, url := range urls {
				images[i] = dto.CommentImageResponse{URL: url}
			}
		}
	}

	// 作者信息
	var author *dto.UserResponse
	if comment.User != nil {
		author = dto.ConvertUserToResponse(comment.User)
	}

	// 帖子简要信息
	var postInfo *dto.AdminCommentPostInfo
	if comment.PostID != "" {
		postInfo = &dto.AdminCommentPostInfo{
			ID: comment.PostID,
		}
		// 尝试获取帖子标题
		post, err := s.postRepo.GetByID(comment.PostID)
		if err == nil && post != nil {
			postInfo.Title = post.Title
		}
	}

	return dto.AdminCommentListResponse{
		ID:           comment.ID,
		PostID:       comment.PostID,
		UserID:       comment.UserID,
		ParentID:     comment.ParentID,
		RootID:       comment.RootID,
		Content:      comment.Content,
		Images:       images,
		Status:       string(comment.Status),
		RejectReason: comment.RejectReason,
		ReviewedAt:   dto.FormatTimePointer(comment.ReviewedAt),
		ReviewedBy:   comment.ReviewedBy,
		LikesCount:   comment.LikesCount,
		RepliesCount: comment.RepliesCount,
		CreatedAt:    comment.CreatedAt.Format("2006-01-02T15:04:05Z07:00"),
		UpdatedAt:    comment.UpdatedAt.Format("2006-01-02T15:04:05Z07:00"),
		Author:       author,
		Post:         postInfo,
	}
}

// convertCommentToAdminDetailResponse 转换评论为管理端详情响应
func (s *adminCommentServiceImpl) convertCommentToAdminDetailResponse(comment *model.Comment) *dto.AdminCommentDetailResponse {
	// 解析图片
	var images []dto.CommentImageResponse
	if comment.Images != "" {
		var urls []string
		if err := json.Unmarshal([]byte(comment.Images), &urls); err == nil {
			images = make([]dto.CommentImageResponse, len(urls))
			for i, url := range urls {
				images[i] = dto.CommentImageResponse{URL: url}
			}
		}
	}

	// 作者信息
	var author *dto.UserResponse
	if comment.User != nil {
		author = dto.ConvertUserToResponse(comment.User)
	}

	// 帖子简要信息
	var postInfo *dto.AdminCommentPostInfo
	if comment.PostID != "" {
		postInfo = &dto.AdminCommentPostInfo{
			ID: comment.PostID,
		}
		// 尝试获取帖子标题
		post, err := s.postRepo.GetByID(comment.PostID)
		if err == nil && post != nil {
			postInfo.Title = post.Title
		}
	}

	return &dto.AdminCommentDetailResponse{
		ID:           comment.ID,
		PostID:       comment.PostID,
		UserID:       comment.UserID,
		ParentID:     comment.ParentID,
		RootID:       comment.RootID,
		Content:      comment.Content,
		Images:       images,
		Status:       string(comment.Status),
		RejectReason: comment.RejectReason,
		ReviewedAt:   dto.FormatTimePointer(comment.ReviewedAt),
		ReviewedBy:   comment.ReviewedBy,
		LikesCount:   comment.LikesCount,
		RepliesCount: comment.RepliesCount,
		CreatedAt:    comment.CreatedAt.Format("2006-01-02T15:04:05Z07:00"),
		UpdatedAt:    comment.UpdatedAt.Format("2006-01-02T15:04:05Z07:00"),
		Author:       author,
		Post:         postInfo,
	}
}