package logic

import (
	"context"
	"crypto/rand"
	"encoding/hex"
	"errors"
	"fmt"
	"strconv"
	"strings"

	"juwan-backend/app/snowflake/rpc/snowflake"
	"juwan-backend/app/users/rpc/internal/models"
	"juwan-backend/app/users/rpc/internal/svc"
	"juwan-backend/app/users/rpc/pb"

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

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

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

func mustNewRandomNickname() string {
	bytes := make([]byte, 5)
	_, err := rand.Read(bytes)
	if err != nil {
		return "NewUser"
	}
	nickname := strings.Builder{}
	nickname.WriteString("user_")
	nickname.WriteString(hex.EncodeToString(bytes))
	return nickname.String()
}

func (l *RegisterLogic) Register(in *pb.RegisterReq) (*pb.RegisterResp, error) {
	// todo: add your logic here and delete this line
	if in.Phone == "" || in.Username == "" || in.Passwd == "" {
		logx.Error("invalid input")
		return nil, errors.New("invalid input")
	}

	redisKey := fmt.Sprintf("vcode:%s:%s:%s", in.RequestId, "register", in.Email)
	vcode, err := l.svcCtx.RedisCluster.Get(l.ctx, redisKey).Result()
	logx.Infof("vcode:%s, err:%v", vcode, err)
	if err != nil {
		logx.Error("invalid verification code")
		return nil, errors.New("invalid verification code")
	}

	code, err := strconv.ParseInt(vcode, 10, 32)
	if err != nil || int32(code) != in.Vcode {
		logx.Error("invalid verification code")
		return nil, errors.New("invalid verification code")
	}

	resp, err := l.svcCtx.Snowflake.NextId(l.ctx, &snowflake.NextIdReq{})
	if err != nil {
		return nil, errors.New("generate user ID failed")
	}

	user := models.Users{
		UserId:     resp.Id,
		Username:   in.Username,
		Nickname:   mustNewRandomNickname(),
		Passwd:     in.Passwd,
		Phone:      in.Phone,
		Email:      in.Email,
		RoleType:   0,
		IsVerified: false,
	}

	_, err = l.svcCtx.UsersModelRW.Insert(l.ctx, &user)
	if err != nil {
		logx.Error("failed to create user: ", err)
		return nil, errors.New("failed to create user")
	}

	return &pb.RegisterResp{
		Res: "user registered successfully",
	}, nil
}