OTP methods

Author: ichtrojan

isis.go

@@ -0,0 +1,68 @@
+package isis
+
+import (
+	"fmt"
+	"gorm.io/gorm"
+	"math/rand"
+	"time"
+)
+
+func Generate(conn *gorm.DB, identifier string, digits int, validity int) (token string, err error) {
+	token = generatePin(digits)
+
+	err = conn.Create(&otp{
+		Identifier: identifier,
+		Token:      token,
+		Validity:   validity,
+		Valid:      true,
+		CreatedAt:  time.Now(),
+		UpdatedAt:  time.Now(),
+	}).Error
+
+	return
+}
+
+func Validate(conn *gorm.DB, identifier string, token string) (validated bool, err error) {
+	var foundOtp otp
+
+	err = conn.Model(otp{}).Where("identifier = ?", identifier).Where("token = ?", token).Find(&foundOtp).Error
+
+	if err != nil {
+		return false, err
+	}
+
+	if foundOtp.Empty() || !foundOtp.Valid {
+		return false, nil
+	}
+
+	conn.First(&foundOtp)
+
+	if foundOtp.Exipired() {
+		foundOtp.Valid = false
+		foundOtp.UpdatedAt = time.Now()
+		conn.Save(&foundOtp)
+
+		return false, nil
+	}
+
+	foundOtp.Valid = false
+	foundOtp.UpdatedAt = time.Now()
+	conn.Save(&foundOtp)
+
+	return true, nil
+}
+
+func generatePin(digits int) string {
+	pin := ""
+
+	rand.Seed(time.Now().UnixNano())
+	min := 0
+	max := 9
+
+	for i := 0; i < digits; i++ {
+		digit := fmt.Sprintf("%d", rand.Intn(max-min+1)+min)
+		pin = pin + digit
+	}
+
+	return pin
+}