tsk-30: Update password (#33)

Closes #30

Reviewed-on: phoenix/textsender-auth#33
Co-authored-by: phoenix <kundeng00@pm.me>
Co-committed-by: phoenix <kundeng00@pm.me>

internal/utility/hashing.go

@@ -1,15 +1,19 @@
 package utility
 
 import (
+	"fmt"
+	"strings"
+	"unicode"
+
 	"golang.org/x/crypto/bcrypt"
 )
 
 type HashMash struct {
-	Password string
+	password string
 }
 
 func (h *HashMash) HashPassword() (string, error) {
-	bytes, err := bcrypt.GenerateFromPassword([]byte(h.Password), bcrypt.DefaultCost)
+	bytes, err := bcrypt.GenerateFromPassword([]byte(h.password), bcrypt.DefaultCost)
 	return string(bytes), err
 }
 
@@ -18,6 +22,41 @@ func (h *HashMash) CheckPasswordHash(password string, hash string) bool {
 	return err == nil
 }
 
-func (h *HashMash) SetPassword(password string) {
-	h.Password = password
+func (h *HashMash) SetPassword(password string) error {
+	if len(password) < 8 {
+		return fmt.Errorf("Password length is not enought")
+	} else if len(password) > 32 {
+		return fmt.Errorf("Password length is too long")
+	} else {
+		specialCharacters := "!@#$%^&*?"
+		numbers := "0123456789"
+		if strings.ContainsAny(password, specialCharacters) && strings.ContainsAny(password, numbers) {
+			var hasAtleastOneUpper, hasAtleastOneLower bool
+
+			for _, c := range password {
+				if unicode.IsUpper(c) {
+					hasAtleastOneUpper = true
+				} else if unicode.IsLower(c) {
+					hasAtleastOneLower = true
+				}
+
+				if hasAtleastOneLower && hasAtleastOneUpper {
+					break
+				}
+			}
+
+			if hasAtleastOneUpper && hasAtleastOneLower {
+				h.password = password
+				return nil
+			} else {
+				if !hasAtleastOneUpper {
+					return fmt.Errorf("Password requires at least one upper case letter")
+				} else {
+					return fmt.Errorf("Password requires at least one lower case letter")
+				}
+			}
+		} else {
+			return fmt.Errorf("Password should contain special characters and numbers")
+		}
+	}
 }