package admin

import (
	"fmt"
	"time"

	"github.com/pingcap/errors"
	"github.com/pingcap/log"
	"github.com/tidbcloud/central-sdk/db"
	"github.com/tidbcloud/central-sdk/db/dbutil"
	"github.com/tidbcloud/central-sdk/db/entity"
	centralModel "github.com/tidbcloud/central-sdk/model"
	"go.uber.org/zap"
	"gorm.io/gorm"
)

type AddTrialCreditReq struct {
	TenantID     uint64
	CreditAmount int64
	Description  string
}

func (m UserContext) AddTrialCredit(req *AddTrialCreditReq) error {
	var t entity.Tenant
	err := db.Transaction(func(tx *gorm.DB) error {
		err := entity.NewTenantQuerySet(tx).IDEq(entity.ID(req.TenantID)).One(&t)
		if err != nil {
			return dbutil.TagNotFound(err)
		}
		if t.Plan == entity.TenantPlanOnDemand {
			return errors.NotValidf("can not add credit to on-demand organization, tenant is %d", t.Name)
		}

		if t.Plan == entity.TenantPlanPOC {
			totalUsage, err := centralModel.GetNodeUsageFromDB(tx, t.ID)
			if err != nil {
				return errors.Annotate(err, "failed to query node usage from DB")
			}
			var oldCredits []entity.FreeTrialPoint
			if err = entity.NewFreeTrialPointQuerySet(tx).TenantIDEq(entity.ID(req.TenantID)).All(&oldCredits); err != nil {
				return errors.Annotate(err, "query credit failed")
			}
			var currentUsage = totalUsage
			for _, item := range oldCredits {
				currentUsage -= item.Amount
			}
			if currentUsage > 0 {
				freeTrialPoint := &entity.FreeTrialPoint{
					TenantID:    entity.ID(req.TenantID),
					Amount:      currentUsage,
					Description: "poc gift",
				}
				if err = freeTrialPoint.Create(tx); err != nil {
					return errors.Annotate(err, "add credit failed")
				}
			}
		}

		freeTrialPoint := &entity.FreeTrialPoint{
			TenantID:    entity.ID(req.TenantID),
			Amount:      req.CreditAmount * 100,
			Description: req.Description,
		}
		if err = freeTrialPoint.Create(tx); err != nil {
			return errors.Annotate(err, "add credit failed")
		}

		return dbutil.AddAccessLogNow(tx, m.tenantAndUser.TenantID, m.tenantAndUser.Email, fmt.Sprintf("add trial $ %d credit for tenant %s", req.CreditAmount, t.Name))
	})
	if err != nil {
		return err
	}

	err = m.mail.SendAddCreditEmail(t.Email, req.CreditAmount)
	if err != nil {
		log.Error("failed to send add credit email", zap.String("email", t.Email), zap.Time("time", time.Now().UTC()), zap.Error(err))
		return err
	}
	log.Info("send add credit email", zap.String("email", t.Email), zap.Time("time", time.Now().UTC()))
	return nil
}