package service

import (
	"time"

	"laic-backend/common"
	"laic-backend/model"
	"laic-backend/vo"
)

const bytesPerGB = 1024 * 1024 * 1024

func (s *AccountService) GetDownloadPage(userID int64, req *vo.UsagePageReq) (*common.PageResponse[vo.DownloadRecordVO], *common.BusiError) {
	type row struct {
		model.DownloadLog
		FileName    string
		FileSize    int64
		DroneSN     string
		ExecutionID int64
	}
	db := common.DB.Table("download_log").Select("download_log.*, video.file_name, video.file_size, video.drone_sn, video.execution_id").Joins("JOIN video ON video.id = download_log.video_id").Where("download_log.user_id = ?", userID)
	var total int64
	if err := db.Count(&total).Error; err != nil {
		return nil, common.ErrInternal
	}
	var rows []row
	if err := db.Scopes(req.Paginate).Order("download_log.created_at DESC, download_log.id DESC").Find(&rows).Error; err != nil {
		return nil, common.ErrInternal
	}
	list := make([]vo.DownloadRecordVO, 0, len(rows))
	for _, row := range rows {
		list = append(list, vo.DownloadRecordVO{ID: row.ID, VideoID: row.VideoID, FileName: row.FileName, FileSize: row.FileSize, DroneSN: row.DroneSN, ExecutionID: row.ExecutionID, Bytes: row.Bytes, CreatedAt: row.CreatedAt})
	}
	return common.Page(req.Pagination, total, list), nil
}

func (s *AccountService) GetResourceSummary(userID int64) (*vo.ResourceSummaryVO, *common.BusiError) {
	balance, busiErr := s.GetTrafficBalance(userID)
	if busiErr != nil {
		return nil, busiErr
	}
	now := time.Now()
	monthStart := time.Date(now.Year(), now.Month(), 1, 0, 0, 0, 0, now.Location())
	var usage struct{ Total, Live, Replay, Download int64 }
	if err := common.DB.Model(&model.TrafficUsageLog{}).Where("user_id = ? AND created_at >= ?", userID, monthStart).Select("COALESCE(SUM(bytes_used), 0) AS total, COALESCE(SUM(CASE WHEN source_type = 'live' THEN bytes_used ELSE 0 END), 0) AS live, COALESCE(SUM(CASE WHEN source_type = 'replay' THEN bytes_used ELSE 0 END), 0) AS replay, COALESCE(SUM(CASE WHEN source_type = 'download' THEN bytes_used ELSE 0 END), 0) AS download").Scan(&usage).Error; err != nil {
		return nil, common.ErrInternal
	}
	var simCount, dockCount, droneCount, videoCount, downloadCount int64
	queries := []struct {
		model  any
		target *int64
		where  string
		args   []any
	}{
		{&model.SimCard{}, &simCount, "user_id = ?", []any{userID}},
		{&model.Dock{}, &dockCount, "user_id = ?", []any{userID}},
		{&model.Drone{}, &droneCount, "user_id = ?", []any{userID}},
		{&model.Video{}, &videoCount, "user_id = ?", []any{userID}},
		{&model.DownloadLog{}, &downloadCount, "user_id = ? AND created_at >= ?", []any{userID, monthStart}},
	}
	for _, query := range queries {
		if err := common.DB.Model(query.model).Where(query.where, query.args...).Count(query.target).Error; err != nil {
			return nil, common.ErrInternal
		}
	}
	toGB := func(value int64) float64 { return float64(value) / bytesPerGB }
	return &vo.ResourceSummaryVO{BalanceGb: balance.BalanceGb, MonthUsageGb: toGB(usage.Total), MonthLiveGb: toGB(usage.Live), MonthReplayGb: toGB(usage.Replay), MonthDownloadGb: toGB(usage.Download), SimCount: simCount, DockCount: dockCount, DroneCount: droneCount, VideoCount: videoCount, MonthDownloadCnt: downloadCount}, nil
}