Add spaces phone validation

src/main/java/seedu/address/model/person/Phone.java

@@ -11,7 +11,7 @@ public class Phone {
 
 
     public static final String MESSAGE_CONSTRAINTS =
-            "Phone numbers should only contain numbers, and it should be at least 3 digits long";
+            "Invalid phone number format. Enter a valid phone number that is more than 3 digits.";
     public static final String VALIDATION_REGEX = "\\d{3,}";
     public final String value;
 
@@ -21,9 +21,13 @@ public class Phone {
      * @param phone A valid phone number.
      */
     public Phone(String phone) {
+
         requireNonNull(phone);
-        checkArgument(isValidPhone(phone), MESSAGE_CONSTRAINTS);
-        value = phone;
+        String trimmedPhone = phone.replaceAll(" ", "");
+        checkArgument(isValidPhone(trimmedPhone), MESSAGE_CONSTRAINTS);
+        value = trimmedPhone;
+
+
     }
 
     /**

src/test/java/seedu/address/model/person/PhoneTest.java

@@ -19,6 +19,22 @@ public void constructor_invalidPhone_throwsIllegalArgumentException() {
         assertThrows(IllegalArgumentException.class, () -> new Phone(invalidPhone));
     }
 
+
+    @Test
+    public void constructor_validPhone_withSpaces() {
+        Phone phoneWithSpaces = new Phone(" 911 ");
+        assertTrue(phoneWithSpaces.equals(new Phone("911"))); // Should equal the trimmed version
+
+        Phone longPhoneWithSpaces = new Phone(" 93121534  ");
+        assertTrue(longPhoneWithSpaces.equals(new Phone("93121534"))); // Should equal the trimmed version
+
+        Phone mixedSpaces1 = new Phone("  1234 5678 ");
+        assertTrue(mixedSpaces1.equals(new Phone("12345678")));
+
+        Phone mixedSpaces2 = new Phone("   98 76 54 32 ");
+        assertTrue(mixedSpaces2.equals(new Phone("98765432")));
+    }
+
     @Test
     public void isValidPhone() {
         // null phone number
@@ -31,6 +47,7 @@ public void isValidPhone() {
         assertFalse(Phone.isValidPhone("phone")); // non-numeric
         assertFalse(Phone.isValidPhone("9011p041")); // alphabets within digits
         assertFalse(Phone.isValidPhone("9312 1534")); // spaces within digits
+        assertFalse(Phone.isValidPhone(" 9312 1534 ")); //spaces around digits
 
         // valid phone numbers
         assertTrue(Phone.isValidPhone("911")); // exactly 3 numbers