package service

import (
	"context"

	"github.com/topfans/backend/pkg/proto/ranking"
	"github.com/topfans/backend/pkg/proto/common"
	"github.com/topfans/backend/services/assetService/client"
	"github.com/topfans/backend/services/assetService/repository"
)

// RankingService 排行榜Service接口
type RankingService interface {
	// GetHotRanking 获取热度排行榜
	GetHotRanking(ctx context.Context, req *ranking.GetRankingRequest) (*ranking.GetRankingResponse, error)

	// GetOriginalRanking 获取自制排行榜
	GetOriginalRanking(ctx context.Context, req *ranking.GetRankingRequest) (*ranking.GetRankingResponse, error)
}

// rankingService 排行榜Service实现
type rankingService struct {
	rankingRepo repository.RankingRepository
	userClient  client.UserServiceClient
}

// NewRankingService 创建排行榜Service实例
func NewRankingService(rankingRepo repository.RankingRepository, userClient client.UserServiceClient) RankingService {
	return &rankingService{
		rankingRepo: rankingRepo,
		userClient:  userClient,
	}
}

// GetHotRanking 获取热度排行榜
func (s *rankingService) GetHotRanking(ctx context.Context, req *ranking.GetRankingRequest) (*ranking.GetRankingResponse, error) {
	// 参数校验
	if req.Dimension == "" {
		req.Dimension = "total"
	}
	if req.Page <= 0 {
		req.Page = 1
	}
	if req.PageSize <= 0 {
		req.PageSize = 10
	}

	starID := req.StarId
	if starID <= 0 {
		// TODO: 从ctx获取当前用户的starID
		starID = 87 // 默认值，待从JWT获取
	}

	offset := (int(req.Page) - 1) * int(req.PageSize)

	// 获取排行榜列表
	var items []*repository.RankingItem
	var total int64
	var err error

	switch req.Dimension {
	case "displaying":
		items, total, err = s.rankingRepo.GetHotRankingDisplaying(starID, int(req.PageSize), offset)
	case "month":
		items, total, err = s.rankingRepo.GetHotRankingMonth(starID, int(req.PageSize), offset)
	case "total":
		items, total, err = s.rankingRepo.GetHotRankingTotal(starID, int(req.PageSize), offset)
	default:
		items, total, err = s.rankingRepo.GetHotRankingTotal(starID, int(req.PageSize), offset)
	}

	if err != nil {
		return &ranking.GetRankingResponse{
			Base: &common.BaseResponse{
				Code:    500,
				Message: "获取排行榜失败: " + err.Error(),
			},
		}, nil
	}

	// 转换结果
	rankingItems := make([]*ranking.RankingItem, len(items))
	for i, item := range items {
		rankingItems[i] = &ranking.RankingItem{
			Rank:           int32(i + 1 + (int(req.Page)-1)*int(req.PageSize)),
			AssetId:        item.AssetID,
			AssetName:      item.AssetName,
			CoverUrl:       item.CoverURL,
			OwnerUid:        item.OwnerUID,
			OwnerNickname:  item.OwnerNickname,
			OwnerAvatar:    getStringPointer(item.OwnerAvatar),
			LikeCount:      item.LikeCount,
			IsOriginal:     item.IsOriginal,
		}
	}

	// 获取当前用户的最佳排名
	var myRanking *ranking.MyRanking
	if req.UserId > 0 && starID > 0 {
		// 获取用户信息（昵称和头像）
		var ownerNickname, ownerAvatar string
		fanProfile, err := s.userClient.GetFanProfile(ctx, req.UserId, starID)
		if err == nil && fanProfile != nil {
			ownerNickname = fanProfile.Nickname
			ownerAvatar = fanProfile.AvatarUrl
		}

		// 获取用户最佳排名（非自制）
		myItem, myRank, err := s.rankingRepo.GetMyBestRanking(req.UserId, starID, req.Dimension, false)
		if err == nil && myItem != nil && myRank > 0 {
			myRanking = &ranking.MyRanking{
				Rank:          myRank,
				AssetId:       myItem.AssetID,
				AssetName:     myItem.AssetName,
				CoverUrl:      myItem.CoverURL,
				LikeCount:     myItem.LikeCount,
				Status:        "ranked",
				OwnerNickname: ownerNickname,
				OwnerAvatar:   ownerAvatar,
			}
		} else {
			// 用户没有上榜，返回默认值
			myRanking = &ranking.MyRanking{
				Rank:          0,
				AssetId:       0,
				AssetName:     "",
				CoverUrl:      "",
				LikeCount:     0,
				Status:        "unranked",
				OwnerNickname: ownerNickname,
				OwnerAvatar:   ownerAvatar,
			}
		}
	}

	return &ranking.GetRankingResponse{
		Base: &common.BaseResponse{
			Code:    200,
			Message: "ok",
		},
		MyRanking: myRanking,
		Items:     rankingItems,
		Page:      req.Page,
		PageSize:  req.PageSize,
		Total:     int32(total),
	}, nil
}

// GetOriginalRanking 获取自制排行榜
func (s *rankingService) GetOriginalRanking(ctx context.Context, req *ranking.GetRankingRequest) (*ranking.GetRankingResponse, error) {
	// 参数校验
	if req.Dimension == "" {
		req.Dimension = "total"
	}
	if req.Page <= 0 {
		req.Page = 1
	}
	if req.PageSize <= 0 {
		req.PageSize = 10
	}

	starID := req.StarId
	if starID <= 0 {
		// TODO: 从ctx获取当前用户的starID
		starID = 87 // 默认值，待从JWT获取
	}

	offset := (int(req.Page) - 1) * int(req.PageSize)

	// 获取排行榜列表
	var items []*repository.RankingItem
	var total int64
	var err error

	switch req.Dimension {
	case "displaying":
		items, total, err = s.rankingRepo.GetOriginalRankingDisplaying(starID, int(req.PageSize), offset)
	case "month":
		items, total, err = s.rankingRepo.GetOriginalRankingMonth(starID, int(req.PageSize), offset)
	case "total":
		items, total, err = s.rankingRepo.GetOriginalRankingTotal(starID, int(req.PageSize), offset)
	default:
		items, total, err = s.rankingRepo.GetOriginalRankingTotal(starID, int(req.PageSize), offset)
	}

	if err != nil {
		return &ranking.GetRankingResponse{
			Base: &common.BaseResponse{
				Code:    500,
				Message: "获取自制排行榜失败: " + err.Error(),
			},
		}, nil
	}

	// 转换结果
	rankingItems := make([]*ranking.RankingItem, len(items))
	for i, item := range items {
		rankingItems[i] = &ranking.RankingItem{
			Rank:           int32(i + 1 + (int(req.Page)-1)*int(req.PageSize)),
			AssetId:        item.AssetID,
			AssetName:      item.AssetName,
			CoverUrl:       item.CoverURL,
			OwnerUid:        item.OwnerUID,
			OwnerNickname:  item.OwnerNickname,
			OwnerAvatar:    getStringPointer(item.OwnerAvatar),
			LikeCount:      item.LikeCount,
			IsOriginal:     item.IsOriginal,
		}
	}

	// 获取当前用户的最佳排名
	var myRanking *ranking.MyRanking
	if req.UserId > 0 && starID > 0 {
		// 获取用户信息（昵称和头像）
		var ownerNickname, ownerAvatar string
		fanProfile, err := s.userClient.GetFanProfile(ctx, req.UserId, starID)
		if err == nil && fanProfile != nil {
			ownerNickname = fanProfile.Nickname
			ownerAvatar = fanProfile.AvatarUrl
		}

		// 获取用户最佳排名（自制）
		myItem, myRank, err := s.rankingRepo.GetMyBestRanking(req.UserId, starID, req.Dimension, true)
		if err == nil && myItem != nil && myRank > 0 {
			myRanking = &ranking.MyRanking{
				Rank:          myRank,
				AssetId:       myItem.AssetID,
				AssetName:     myItem.AssetName,
				CoverUrl:      myItem.CoverURL,
				LikeCount:     myItem.LikeCount,
				Status:        "ranked",
				OwnerNickname: ownerNickname,
				OwnerAvatar:   ownerAvatar,
			}
		} else {
			// 用户没有上榜，返回默认值
			myRanking = &ranking.MyRanking{
				Rank:          0,
				AssetId:       0,
				AssetName:     "",
				CoverUrl:      "",
				LikeCount:     0,
				Status:        "unranked",
				OwnerNickname: ownerNickname,
				OwnerAvatar:   ownerAvatar,
			}
		}
	}

	return &ranking.GetRankingResponse{
		Base: &common.BaseResponse{
			Code:    200,
			Message: "ok",
		},
		MyRanking: myRanking,
		Items:     rankingItems,
		Page:      req.Page,
		PageSize:  req.PageSize,
		Total:     int32(total),
	}, nil
}

// getStringPointer 返回字符串的指针
func getStringPointer(s *string) string {
	if s == nil {
		return ""
	}
	return *s
}