package cf

import (
	"math/rand"
	"regexp"
)

// 是否是手机号
func IsMobile(str string) bool {
	return regexp.MustCompile(`^1[3-9]\d{9}$`).MatchString(str)
}

// 随机字符串
var letters = []rune("0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")

// 获取随机字符串
func StrRand(strLen int) string {
	randBytes := make([]rune, strLen)
	for i := range randBytes {
		randBytes[i] = letters[rand.Intn(len(letters))]
	}
	return string(randBytes)
}

// 随机字母字符串
var charLetters = []rune("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ")

// 随机字母字符串
func StrCharRand(strLen int) string {
	randBytes := make([]rune, strLen)
	for i := range randBytes {
		randBytes[i] = charLetters[rand.Intn(len(charLetters))]
	}
	return string(randBytes)
}

// 随机数字字符串
// 第一位不能是0
func StrNumberRand(strLen int) string {
	numberLetters := []rune("0123456789")
	randBytes := make([]rune, strLen)
	for i := range randBytes {
		if i == 0 {
			randBytes[i] = letters[rand.Intn(9)]
		} else {
			randBytes[i] = letters[rand.Intn(len(numberLetters))]
		}
	}
	return string(randBytes)
}