package srv_user

import (
	"context"
	"strings"
	"time"
	"videoweb/pub/common/srvdef"
	"videoweb/pub/models/cointransmod"
	"videoweb/pub/models/rechargepackagemod"
	"videoweb/pub/models/usermod"
	"videoweb/pub/payment"
	"videoweb/pub/pubdef"

	"go.mongodb.org/mongo-driver/bson"
	"go.mongodb.org/mongo-driver/mongo/options"
)

// GetUsers 分页查询用户列表
func GetUsers(ctx context.Context, req *UserListReq) (*UserListResp, *srvdef.SrvErr) {
	filter := bson.M{}
	if req.Id != nil && *req.Id > 0 {
		filter[usermod.FN.User.Id] = *req.Id
	}
	if accountNo := strings.TrimSpace(req.AccountNo); accountNo != "" {
		filter[usermod.FN.User.AccountNo] = accountNo
	}
	if email := strings.TrimSpace(req.Email); email != "" {
		filter[usermod.FN.User.Email] = email
	}
	if req.NickName != "" {
		filter[usermod.FN.User.NickName] = bson.M{"$regex": req.NickName}
	}
	if districtCode := strings.TrimSpace(req.DistrictCode); districtCode != "" {
		filter[usermod.FN.User.DistrictCode] = districtCode
	}
	if req.Status != nil {
		filter[usermod.FN.User.Status] = *req.Status
	}
	if req.Type != nil {
		filter[usermod.FN.User.Type] = *req.Type
	}

	opts := options.Find().
		SetSort(bson.M{usermod.FN.User.Id: -1}).
		SetSkip((req.PageNum - 1) * req.PageSize).
		SetLimit(req.PageSize)

	resp := &UserListResp{}
	total, serr := usermod.CountUsers(ctx, filter)
	if serr != nil {
		return resp, serr
	}
	resp.Total = total
	if total == 0 {
		return resp, nil
	}
	list, serr := usermod.FindManyUser(ctx, filter, opts)
	if serr != nil {
		return resp, serr
	}
	resp.List = list
	return resp, nil
}

// UpdateUser 更新指定用户信息
func UpdateUser(ctx context.Context, id int64, param usermod.UserUpdate) *srvdef.SrvErr {
	now := time.Now()
	param.UpdatedAt = &now
	return usermod.UpdateOneUser(ctx,
		bson.M{usermod.FN.User.Id: id},
		bson.M{"$set": param},
	)
}

// GiftCoin 给用户赠送/扣除金币，并写入流水记录
// coin 为正数时增加余额，为负数时扣减（不校验余额是否充足，由调用方确保）
func GiftCoin(ctx context.Context, req *GiftCoinReq) *srvdef.SrvErr {
	if req.Coin == 0 {
		return srvdef.New(srvdef.ErrParamError, "金币数量不能为 0", "")
	}

	// 原子更新余额
	if serr := usermod.UpdateOneUser(ctx,
		bson.M{usermod.FN.User.Id: req.UserId},
		bson.M{
			"$inc": bson.M{usermod.FN.User.Recharge: req.Coin},
			"$set": bson.M{usermod.FN.User.UpdatedAt: time.Now()},
		},
	); serr != nil {
		return serr
	}

	// 写流水（更新后再查余额，作为 balanceAfter）
	flowDir := cointransmod.FlowIn
	amount := req.Coin
	if req.Coin < 0 {
		flowDir = cointransmod.FlowOut
		amount = -req.Coin
	}
	remark := req.Remark
	if remark == "" {
		remark = payment.CoinTransRemark(cointransmod.TranTypeAdminAdjust, "")
	}
	_ = payment.WriteCoinTransByUser(ctx, payment.WriteCoinTransOpt{
		UserId:   req.UserId,
		FlowDir:  flowDir,
		TranType: cointransmod.TranTypeAdminAdjust,
		Amount:   amount,
		Remark:   remark,
	})

	return nil
}

// UpdateVip 根据会员畅享套餐修改用户会员信息。
func UpdateVip(ctx context.Context, req *UpdateVipReq) *srvdef.SrvErr {
	if req == nil || req.UserId <= 0 || req.PackageId <= 0 {
		return srvdef.New(srvdef.ErrParamError, "用户ID和套餐ID不能为空", "")
	}
	user, serr := usermod.FindOneUser(ctx, bson.M{usermod.FN.User.Id: req.UserId})
	if serr != nil || user == nil {
		return srvdef.New(srvdef.ErrUserNotExsit, "", "")
	}
	pkg, serr := rechargepackagemod.FindOneRechargePackage(ctx, bson.M{
		rechargepackagemod.FN.RechargePackage.Id:          req.PackageId,
		rechargepackagemod.FN.RechargePackage.PackageType: rechargepackagemod.PackageTypeVip,
		rechargepackagemod.FN.RechargePackage.Status:      rechargepackagemod.StatusEnabled,
	})
	if serr != nil || pkg == nil {
		return srvdef.New(srvdef.ErrNoData, "会员套餐不存在或未启用", "")
	}
	if pkg.DurationDays <= 0 {
		return srvdef.New(srvdef.ErrParamError, "会员套餐有效天数无效", "")
	}

	now := time.Now()
	baseTime := now
	if user.CurrentVipExpire.After(now) {
		baseTime = user.CurrentVipExpire
	}
	newExpire := baseTime.Add(time.Duration(pkg.DurationDays) * 24 * time.Hour)
	updateDoc := bson.M{
		"$set": bson.M{
			usermod.FN.User.VipType:          vipTypeFromDurationDays(pkg.DurationDays),
			usermod.FN.User.ShowCardId:       pkg.Id,
			usermod.FN.User.ShowCardName:     pkg.Name,
			usermod.FN.User.CurrentVipExpire: newExpire,
			usermod.FN.User.UpdatedAt:        now,
		},
	}

	if serr = usermod.UpdateOneUser(ctx, bson.M{usermod.FN.User.Id: req.UserId}, updateDoc); serr != nil {
		return serr
	}
	return nil
}

func vipTypeFromDurationDays(days int64) pubdef.VipType {
	if days >= 365 {
		return pubdef.VipTypeYear
	}
	if days > 0 {
		return pubdef.VipTypeMonth
	}
	return pubdef.VipTypeNone
}