package service

import (
	"filestoragesystem/internal/config"
	"filestoragesystem/internal/repository"
	"filestoragesystem/pkg/apperr"
)

// StatsService 存储与流量统计服务
type StatsService struct {
	cfg         *config.Config
	userRepo    *repository.UserRepo
	projectRepo *repository.ProjectRepo
	fileRepo    *repository.FileRepo
	trafficRepo *repository.TrafficRepo
}

// UserStats 用户存储统计：总体 + 项目明细 + 流量汇总
func (s *StatsService) UserStats(userID uint) (map[string]interface{}, error) {
	user, err := s.userRepo.FindByID(userID)
	if err != nil {
		return nil, err
	}
	fileCount, totalSize, err := s.fileRepo.StatsByUser(userID)
	if err != nil {
		return nil, err
	}

	projects, err := s.projectRepo.ListByUser(userID)
	if err != nil {
		return nil, err
	}
	projectStats := make([]map[string]interface{}, 0, len(projects))
	for _, p := range projects {
		count, size, err := s.fileRepo.StatsByProject(p.ID)
		if err != nil {
			continue
		}
		projectStats = append(projectStats, map[string]interface{}{
			"project_id":    p.ID,
			"name":          p.Name,
			"file_count":    count,
			"storage_used":  size,
			"storage_limit": p.StorageLimit,
		})
	}

	upload30, download30, _ := s.trafficRepo.SumByUser(userID, 30)
	uploadAll, downloadAll, _ := s.trafficRepo.SumByUser(userID, 0)

	return map[string]interface{}{
		"storage_used":  user.StorageUsed,
		"storage_limit": user.StorageLimit,
		"file_count":    fileCount,
		"total_size":    totalSize,
		"project_count": len(projects),
		"projects":      projectStats,
		"traffic": map[string]interface{}{
			"upload_30d":     upload30,
			"download_30d":   download30,
			"upload_total":   uploadAll,
			"download_total": downloadAll,
		},
	}, nil
}

// ProjectStats 项目存储统计
func (s *StatsService) ProjectStats(userID uint, projectID uint, isAdmin bool) (map[string]interface{}, error) {
	p, err := s.projectRepo.FindByID(projectID)
	if err != nil {
		return nil, err
	}
	if !isAdmin && p.UserID != userID {
		return nil, apperr.ErrForbidden
	}
	count, size, err := s.fileRepo.StatsByProject(projectID)
	if err != nil {
		return nil, err
	}
	var trashed int64
	s.fileRepo.DB.Table("files").Where("project_id = ? AND status = 0", projectID).Count(&trashed)

	return map[string]interface{}{
		"project_id":    p.ID,
		"name":          p.Name,
		"file_count":    count,
		"storage_used":  size,
		"storage_limit": p.StorageLimit,
		"trash_count":   trashed,
	}, nil
}

// TrafficStats 流量统计：按天聚合 + 汇总
func (s *StatsService) TrafficStats(userID uint, days int) (map[string]interface{}, error) {
	if days <= 0 {
		days = 30
	}
	daily, err := s.trafficRepo.DailyStats(userID, days)
	if err != nil {
		return nil, err
	}
	upload, download, _ := s.trafficRepo.SumByUser(userID, days)
	return map[string]interface{}{
		"days":     days,
		"daily":    daily,
		"upload":   upload,
		"download": download,
	}, nil
}