package trafficusage

import (
	"context"
	"fmt"
	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/consts"
	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/dao"
	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/library/rabbitmq"
	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/model"
	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/model/entity"
	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/internal/service"
	"time"

	"git.5iot.com/iotlcm-public/iotlcm-admin-svr/utility/uuid32"
	"github.com/gogf/gf/v2/frame/g"
)

const (
	trafficUsageDailyPageSize = 100
)

type sTrafficUsageDailySync struct {
}

// These indirections keep the trigger deterministic in unit tests without changing
// the production publisher, clock, or run-id generator.
var (
	dailyUsageNow           = time.Now
	dailyUsageRunID         = uuid32.S
	dailyUsageRabbitEnabled = rabbitmq.Enabled
	dailyUsagePublish       = rabbitmq.Publish
)

func NewTrafficUsageDailySync() *sTrafficUsageDailySync {
	return &sTrafficUsageDailySync{}
}

func init() {
	service.RegisterTrafficUsageDailySync(NewTrafficUsageDailySync())
}

// StartDaily publishes one command for Worker to execute the previous-day usage
// full sync. Admin deliberately does not scan cards or call an upstream service;
// Worker owns pacing, retries, the failure pool and replay.
func (s *sTrafficUsageDailySync) StartDaily(ctx context.Context) error {
	_, err := s.StartDailyRun(ctx)
	return err
}

func (s *sTrafficUsageDailySync) StartDailyRun(ctx context.Context) (string, error) {
	return s.StartDailyRunScoped(ctx, nil)
}

// StartDailyRunScoped starts a run restricted to scope.Channels. A nil scope, or
// one whose channels normalize to empty, starts a full sync.
func (s *sTrafficUsageDailySync) StartDailyRunScoped(ctx context.Context, scope *model.SyncScope) (string, error) {
	return s.StartDailyRunScopedAt(ctx, scope, "")
}

// StartDailyRunScopedAt starts a run for the given day (yyyyMMdd). An empty
// queryDate keeps the historical behaviour and covers the previous calendar day
// in the business timezone; a non-empty value lets an operator backfill one
// specific past day.
func (s *sTrafficUsageDailySync) StartDailyRunScopedAt(ctx context.Context, scope *model.SyncScope, queryDate string) (string, error) {
	if ctx == nil {
		ctx = context.Background()
	}
	startedAt := time.Now()
	normalized, err := model.NormalizeScope(scope)
	if err != nil {
		g.Log().Errorf(ctx, "event=daily_usage_trigger status=failed stage=validate durationMs=%d error=%q", elapsedMilliseconds(startedAt), err.Error())
		return "", err
	}
	if !dailyUsageRabbitEnabled(ctx) {
		err := fmt.Errorf("daily usage start skipped: rabbitmq is disabled")
		g.Log().Errorf(ctx, "event=daily_usage_trigger status=failed stage=precheck durationMs=%d reason=%q", elapsedMilliseconds(startedAt), err.Error())
		return "", err
	}

	location, err := time.LoadLocation("Asia/Shanghai")
	if err != nil {
		g.Log().Errorf(ctx, "event=daily_usage_trigger status=failed stage=timezone durationMs=%d error=%q", elapsedMilliseconds(startedAt), err.Error())
		return "", fmt.Errorf("load daily usage timezone: %w", err)
	}
	resolvedDate, err := resolveDailyQueryDate(dailyUsageNow().In(location), location, queryDate)
	if err != nil {
		g.Log().Errorf(ctx, "event=daily_usage_trigger status=failed stage=validate reason=invalid_query_date queryDate=%q durationMs=%d error=%q", queryDate, elapsedMilliseconds(startedAt), err.Error())
		return "", err
	}
	message := model.TrafficUsageDailyStartMessage{
		RunID:       fmt.Sprintf("daily-usage-%s-%s", resolvedDate, dailyUsageRunID()),
		Operation:   model.OperationPreviousDayUsageFullSync,
		QueryDate:   resolvedDate,
		TriggeredAt: dailyUsageNow().In(location).Format(time.RFC3339),
		Scope:       normalized,
	}
	if err = dailyUsagePublish(ctx, consts.QueueTrafficUsageDailyStart, message); err != nil {
		g.Log().Errorf(ctx, "event=daily_usage_trigger status=failed stage=publish runId=%s queryDate=%s durationMs=%d error=%q", message.RunID, message.QueryDate, elapsedMilliseconds(startedAt), err.Error())
		return "", fmt.Errorf("publish daily usage start: %w", err)
	}
	g.Log().Infof(ctx, "event=daily_usage_trigger status=published runId=%s queryDate=%s triggeredAt=%s durationMs=%d", message.RunID, message.QueryDate, message.TriggeredAt, elapsedMilliseconds(startedAt))
	return message.RunID, nil
}

// minBackfillDay is the earliest day a manual backfill may target. It only
// catches obvious typos; it is not a business boundary. Comparing the
// zero-padded yyyyMMdd strings sorts chronologically.
const minBackfillDay = "20200101"

// resolveDailyQueryDate returns the day a run must cover. An empty requested
// value keeps the legacy default (the previous day in the business timezone);
// otherwise the value is validated and returned in canonical yyyyMMdd form.
func resolveDailyQueryDate(now time.Time, location *time.Location, requested string) (string, error) {
	// The default covers the previous calendar day, which is the same period the
	// legacy admin scan used.
	yesterday := time.Date(now.Year(), now.Month(), now.Day(), 0, 0, 0, 0, location).AddDate(0, 0, -1)
	if requested == "" {
		return yesterday.Format("20060102"), nil
	}
	parsed, err := time.ParseInLocation("20060102", requested, location)
	if err != nil {
		return "", fmt.Errorf("invalid queryDate %q: want yyyyMMdd", requested)
	}
	if parsed.After(yesterday) {
		return "", fmt.Errorf("invalid queryDate %q: must not be later than %s", requested, yesterday.Format("20060102"))
	}
	if parsed.Format("20060102") < minBackfillDay {
		return "", fmt.Errorf("invalid queryDate %q: must not be earlier than %s", requested, minBackfillDay)
	}
	return parsed.Format("20060102"), nil
}

// SyncDaily is the legacy in-process scan. It is retained as the rollback path
// until the worker chain is verified in production, and it is no longer
// registered on any timer.
func (s *sTrafficUsageDailySync) SyncDaily(ctx context.Context) {
	now := time.Now().In(historyUsageLocation)
	yesterday := now.AddDate(0, 0, -1)
	queryDate := yesterday.Format("20060102")
	date := time.Date(yesterday.Year(), yesterday.Month(), yesterday.Day(), 0, 0, 0, 0, historyUsageLocation)

	cardColumns := dao.TSimCardInfo.Columns()
	cardTable := dao.TSimCardInfo.Table()
	snapshotMaxID, err := trafficUsageEligibleCardModel(ctx).Max(cardTable + "." + cardColumns.Id)
	if err != nil {
		g.Log().Errorf(ctx, "SyncTrafficUsageDaily snapshot sim cards failed: %+v", err)
		return
	}
	maxID := int64(snapshotMaxID)
	if maxID <= 0 {
		return
	}

	var lastID int64
	for lastID < maxID {
		list := []entity.TSimCardInfo{}
		if err = trafficUsageEligibleCardModel(ctx).
			Fields(trafficUsageCardFields()).
			WhereGT(cardTable+"."+cardColumns.Id, lastID).
			WhereLTE(cardTable+"."+cardColumns.Id, maxID).
			OrderAsc(cardTable + "." + cardColumns.Id).
			Limit(trafficUsageDailyPageSize).
			Scan(&list); err != nil {
			g.Log().Errorf(ctx, "SyncTrafficUsageDaily list sim cards failed, lastId:%d, err:%+v", lastID, err)
			return
		}
		if len(list) == 0 {
			return
		}
		lastID = list[len(list)-1].Id

		cardMap := trafficUsageDailyCardMap(list)
		simKeys := trafficUsageDailySimKeys(list)
		output, err := service.UpstreamChan().QuerySimDatausageDaily(ctx, &model.SimDataUsageDailyInput{
			SimKeys: simKeys,
			ReqData: model.SimDataUsageDailyInputItem{
				QueryDate: queryDate,
			},
		})
		if err != nil {
			g.Log().Errorf(ctx, "SyncTrafficUsageDaily query daily failed, lastId:%d, count:%d, err:%+v", lastID, len(simKeys), err)
			for _, simKey := range simKeys {
				s.publishRetry(ctx, simKey, cardMap[simKey.ICCID], queryDate)
			}
			continue
		}

		success, failed := reconcileUsageWithPeriod(simKeys, output, func(item model.SimDataUsageDailyOutputItem) float64 { return item.DataAmount }, func(item model.SimDataUsageDailyOutputItem) string { return item.QueryDate }, normalizeUsageDay, queryDate)
		for _, key := range failed {
			s.publishRetry(ctx, key, cardMap[key.ICCID], queryDate)
		}

		if items := s.buildDailyItems(success, cardMap, date); len(items) > 0 {
			if err = service.TrafficUsage().UpdateDaily(ctx, items); err != nil {
				g.Log().Errorf(ctx, "SyncTrafficUsageDaily write tdengine failed, lastId:%d, err:%+v", lastID, err)
				for _, item := range success {
					s.publishRetry(ctx, item.SimKey, cardMap[item.SimKey.ICCID], queryDate, item.ResData.DataAmount)
				}
			}
		}
	}
}

// buildDailyItems 构建SIM卡的流量使用记录
func (s *sTrafficUsageDailySync) buildDailyItems(output []model.SimBaseRes[model.SimDataUsageDailyOutputItem], cardMap map[string]model.TrafficUsageSimCard, date time.Time) []model.TrafficUsageDailyItem {
	items := make([]model.TrafficUsageDailyItem, 0, len(output))
	for _, item := range output {
		if item.SimKey == nil {
			continue
		}
		card := cardMap[item.SimKey.ICCID]
		items = append(items, model.TrafficUsageDailyItem{
			TrafficUsageBase: model.TrafficUsageBase{
				Iccid:       item.SimKey.ICCID,
				UsageMb:     item.ResData.DataAmount,
				PackageCode: card.PackageCode,
			},
			Date: date,
		})
	}
	return items
}

// publishRetry 发布重试消息
func (s *sTrafficUsageDailySync) publishRetry(ctx context.Context, simKey *model.SimKey, card model.TrafficUsageSimCard, queryDate string, usage ...float64) {
	var snapshot *float64
	if len(usage) > 0 {
		snapshot = &usage[0]
	}
	if !rabbitmq.Enabled(ctx) {
		g.Log().Errorf(ctx, "traffic usage daily retry skipped, rabbitmq disabled, simKey:%+v, queryDate:%s", simKey, queryDate)
		return
	}
	if err := rabbitmq.PublishConfirmed(ctx, consts.QueueTrafficUsageDailyRetry, model.TrafficUsageDailyRetryMessage{
		UsageMb:   snapshot,
		SimKey:    simKey,
		Card:      card,
		QueryDate: queryDate,
	}); err != nil {
		g.Log().Errorf(ctx, "publish traffic usage daily retry failed, simKey:%+v, queryDate:%s, err:%+v", simKey, queryDate, err)
	}
}

// trafficUsageDailySimKeys 提取SIM卡的ChanKey、ICCID、IMSI、MSISDN
func trafficUsageDailySimKeys(list []entity.TSimCardInfo) []*model.SimKey {
	simKeys := make([]*model.SimKey, 0, len(list))
	for _, item := range list {
		simKeys = append(simKeys, &model.SimKey{
			ChanKey: item.ChanKey,
			ICCID:   item.Iccid,
			IMSI:    item.Imsi,
			MSISDN:  item.Msisdn,
		})
	}
	return simKeys
}

// trafficUsageDailyCardMap 提取SIM卡的ChanKey、ICCID、IMSI、MSISDN、PackageCode、FlowPoolCode、IsFlowPool
func trafficUsageDailyCardMap(list []entity.TSimCardInfo) map[string]model.TrafficUsageSimCard {
	cardMap := make(map[string]model.TrafficUsageSimCard, len(list))
	for _, item := range list {
		cardMap[item.Iccid] = model.TrafficUsageSimCard{
			Iccid:       item.Iccid,
			PackageCode: item.CurrentPackageCode,
		}
	}
	return cardMap
}