33 lines
669 B
Go
33 lines
669 B
Go
package usecase
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import (
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"crypto/rand"
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"fmt"
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"math/big"
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"strconv"
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)
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func generateVerifyCode(digits int) (string, error) {
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// 預設為六位數
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if digits <= 0 {
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digits = 6
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}
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// 計算最大值 (10^digits - 1)
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exp := new(big.Int).Exp(big.NewInt(10), big.NewInt(int64(digits)), nil)
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// 生成隨機數
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randomNumber, err := rand.Int(rand.Reader, exp)
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if err != nil {
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return "", err
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}
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// 將隨機數轉換為 string
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verifyCode := strconv.Itoa(int(randomNumber.Int64()))
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// 如果隨機數的位數少於指定的位數，則補 0
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if len(verifyCode) < digits {
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verifyCode = fmt.Sprintf("%0*d", digits, randomNumber)
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}
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return verifyCode, nil
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}
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