package walletservicelogic

import (
	"context"
	"database/sql"
	"errors"
	"github.com/zeromicro/go-zero/core/stores/sqlx"
	"tianyuan-api/apps/sentinel/client/product"
	"tianyuan-api/apps/sentinel/sentinel"
	"tianyuan-api/apps/user/internal/model"
	"time"

	"tianyuan-api/apps/user/internal/svc"
	"tianyuan-api/apps/user/user"

	"github.com/zeromicro/go-zero/core/logx"
)

type UpdateWalletLogic struct {
	ctx    context.Context
	svcCtx *svc.ServiceContext
	logx.Logger
}

func NewUpdateWalletLogic(ctx context.Context, svcCtx *svc.ServiceContext) *UpdateWalletLogic {
	return &UpdateWalletLogic{
		ctx:    ctx,
		svcCtx: svcCtx,
		Logger: logx.WithContext(ctx),
	}
}

const maxRetries = 5 // 最大重试次数
// 修改钱包余额
func (l *UpdateWalletLogic) UpdateWallet(in *user.UpdateWalletRequest) (*user.UpdateWalletResponse, error) {
	if !in.Charge {
		return nil, errors.New("不需要扣款")
	}
	// 获取产品信息
	consumeProduct, getProductByCodeErr := l.svcCtx.ProductRpc.GetProductByCode(l.ctx, &product.GetRecordByCodeRequest{Code: in.ProductCode})
	if getProductByCodeErr != nil {
		return nil, getProductByCodeErr
	}
	userProduct, getUserProductErr := l.svcCtx.UserProductRpc.GetUserProduct(l.ctx, &sentinel.UserProuctRequest{
		UserId:    in.UserId,
		ProductId: consumeProduct.Id,
	})
	if getUserProductErr != nil {
		return nil, getUserProductErr
	}
	// 检查是否已经扣款
	deduction, FindOneByTransactionIdErr := l.svcCtx.DeductionsModel.FindOneByTransactionId(l.ctx, in.TransactionId)
	if FindOneByTransactionIdErr != nil {
		if FindOneByTransactionIdErr == sql.ErrNoRows {
		} else {
			// 其他错误，直接返回
			return nil, FindOneByTransactionIdErr
		}
	} else if deduction != nil {
		// 找到扣款记录，不能重复扣款
		return nil, errors.New("该订单已扣款")
	}

	// 启动事务
	err := l.svcCtx.WalletsModel.TransCtx(l.ctx, func(ctx context.Context, session sqlx.Session) error {
		var err error
		// 尝试多次更新余额（用于乐观锁）
		for i := 0; i < maxRetries; i++ {
			err = l.svcCtx.WalletsModel.UpdateBalance(session, l.ctx, in.UserId, -userProduct.ProductPrice)
			if err == nil {
				// 成功，退出循环
				break
			}
			if errors.Is(err, model.ErrVersionMismatch) {
				// 版本号不匹配，重试
				time.Sleep(100 * time.Millisecond) // 重试前的延迟
				continue
			} else {
				// 其他错误，直接返回
				return err
			}
		}

		if err != nil {
			return err
		}

		// 更新余额成功后，插入扣款记录
		_, err = l.svcCtx.DeductionsModel.InsertDeductionsTrans(ctx, &model.Deductions{
			TransactionId: in.TransactionId,
			UserId:        in.UserId,
			Amount:        userProduct.ProductPrice,
		}, session)
		if err != nil {
			return err
		}
		return nil
	})
	if err != nil {
		return nil, err
	}
	// 获取最新的用户余额
	wallet, err := l.svcCtx.WalletsModel.FindOneByUserId(l.ctx, in.UserId)
	if err != nil {
		return nil, err
	}

	// 如果余额小于 0，更新 QuotaExceeded 字段为 1
	if wallet.Balance < 0 {
		users, findOneErr := l.svcCtx.UserModel.FindOne(l.ctx, in.UserId)
		if findOneErr != nil {
			return nil, findOneErr
		}
		users.QuotaExceeded = 1
		updateErr := l.svcCtx.UserModel.Update(l.ctx, users)
		if updateErr != nil {
			return nil, updateErr
		}
	}
	return &user.UpdateWalletResponse{}, nil
}