// Licensed to the Apache Software Foundation (ASF) under one or more
// contributor license agreements.  See the NOTICE file distributed with
// this work for additional information regarding copyright ownership.
// The ASF licenses this file to You under the Apache License, Version 2.0
// (the "License"); you may not use this file except in compliance with
// the License.  You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

package utils

import (
	"math/rand"
	"time"
)

var letters = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789")
var numbers = []rune("0123456789")

func init() {
	rand.Seed(time.Now().UnixNano())
}

func RandomStr(length uint32) string {
	if length == 0 {
		return ""
	}
	ret := make([]rune, 0, length)
	for i := 0; i < int(length); i++ {
		ret = append(ret, letters[rand.Intn(len(letters))])
	}
	return string(ret)
}

func RandomNumberStr(length uint32) string {
	if length == 0 {
		return ""
	}
	ret := make([]rune, 0, length)
	for i := 0; i < int(length); i++ {
		ret = append(ret, numbers[rand.Intn(len(numbers))])
	}
	return string(ret)
}
