Improve date parsing

src/main/java/hallpointer/address/model/member/Room.java

@@ -9,7 +9,7 @@
  */
 public class Room {
 
-    public static final String MESSAGE_CONSTRAINTS = "Room should be in the format block-floor-room number.\n"
+    public static final String MESSAGE_CONSTRAINTS = "Room must be in the format block-floor-room number.\n"
             + "Example: 10-3-100\n"
             + "Unfortunately, non-numeric block or room numbers are currently unsupported.";
 

src/main/java/hallpointer/address/model/member/Telegram.java

@@ -54,7 +54,6 @@ public boolean equals(Object other) {
         }
 
         Telegram otherTelegram = (Telegram) other;
-        System.out.println(value.equals(otherTelegram.value));
         return value.equals(otherTelegram.value);
     }
 

src/main/java/hallpointer/address/model/session/SessionDate.java

@@ -6,6 +6,8 @@
 import java.time.LocalDate;
 import java.time.format.DateTimeFormatter;
 import java.time.format.DateTimeParseException;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
 
 /**
  * Represents a SessionDate.
@@ -14,11 +16,14 @@
 public class SessionDate {
 
     public static final String MESSAGE_CONSTRAINTS =
-            "Dates should be in the format dd MMM yyyy.\n"
+            "Dates must be in the format dd MMM yyyy,\n"
+                    + "although it is case-insensitive and does not need zero-padding.\n"
                     + "Example: 24 Sep 2024";
 
     // Desired date format
     public static final DateTimeFormatter DATE_FORMATTER = DateTimeFormatter.ofPattern("dd MMM yyyy");
+    // Whitespace processing already done earlier
+    public static final Pattern parsingPattern = Pattern.compile("^([0-9]{1,2}) ([a-zA-Z]{3}) ([0-9]{4})$");
 
     public final LocalDate fullDate;
 
@@ -30,16 +35,45 @@ public class SessionDate {
     public SessionDate(String date) {
         requireNonNull(date);
         checkArgument(isValidDate(date), MESSAGE_CONSTRAINTS);
-        fullDate = LocalDate.parse(date, DATE_FORMATTER);
+        fullDate = LocalDate.parse(manualFormatDate(date), DATE_FORMATTER);
+    }
+
+    /**
+     * Parses minor errors in date formatting and fixes them.
+     * Minor errors in this case referring to zero-padding and month case.
+     *
+     * @param date the input date in question
+     * @return the correctly formatted date
+     */
+    private static String manualFormatDate(String date) {
+        requireNonNull(date);
+        Matcher matcher = parsingPattern.matcher(date);
+        if (!matcher.find()) {
+            return ""; // no amount of formatting can save this given the input constraints
+        }
+        // matcher.group(0) returns the whole string
+        String day = matcher.group(1);
+        String month = matcher.group(2);
+        String year = matcher.group(3);
+
+        // Fix zero-padding requirement
+        if (day.length() == 1) {
+            day = "0" + day;
+        }
+        // Fix month case issue
+        month = month.substring(0, 1).toUpperCase() + month.substring(1).toLowerCase();
+        // Nothing can be done about year errors due to ambiguity
+        return day + " " + month + " " + year;
     }
 
     /**
      * Returns true if a given string is a valid date and has the expected format.
      */
-    public static boolean isValidDate(String test) {
+    public static boolean isValidDate(String date) {
         try {
-            LocalDate parsedDate = LocalDate.parse(test, DATE_FORMATTER);
-            return parsedDate.format(DATE_FORMATTER).equals(test);
+            String formattedDate = manualFormatDate(date);
+            LocalDate parsedDate = LocalDate.parse(formattedDate, DATE_FORMATTER);
+            return parsedDate.format(DATE_FORMATTER).equals(formattedDate); // throws error if it doesn't work
         } catch (DateTimeParseException e) {
             return false;
         }

src/main/java/hallpointer/address/model/tag/Tag.java

@@ -9,7 +9,7 @@
  */
 public class Tag {
 
-    public static final String MESSAGE_CONSTRAINTS = "Tag names should be alphanumeric and without spaces.";
+    public static final String MESSAGE_CONSTRAINTS = "Tag names must be alphanumeric and without spaces.";
     public static final String VALIDATION_REGEX = "\\p{Alnum}+";
 
     public final String tagName;

src/test/java/hallpointer/address/model/session/SessionDateTest.java

@@ -33,19 +33,33 @@ public void isValidDate() {
         assertFalse(SessionDate.isValidDate("24 September 2024")); // wrong format
         assertFalse(SessionDate.isValidDate("Oct 24 2024")); // wrong format
         assertFalse(SessionDate.isValidDate("2024 24 Sep")); // wrong format
+        assertFalse(SessionDate.isValidDate("333 Mar 2024")); // invalid day
+        assertFalse(SessionDate.isValidDate("30 m 2024")); // invalid month
+        assertFalse(SessionDate.isValidDate("30 Mar 024")); // invalid year
+        assertFalse(SessionDate.isValidDate(" Mar 2024")); // missing day
+        assertFalse(SessionDate.isValidDate("29  2024")); // missing month
+        assertFalse(SessionDate.isValidDate("30 Mar ")); // missing year
 
         // valid dates
-        assertTrue(SessionDate.isValidDate("24 Sep 2024")); // valid date
-        assertTrue(SessionDate.isValidDate("01 Jan 2000")); // valid date
-        assertTrue(SessionDate.isValidDate("15 Aug 2023")); // valid date
+        assertTrue(SessionDate.isValidDate("24 Sep 2024"));
+        assertTrue(SessionDate.isValidDate("01 Jan 2000"));
+        assertTrue(SessionDate.isValidDate("15 Aug 2023"));
+        assertTrue(SessionDate.isValidDate("1 Jan 2000")); // no zero-padding
+        assertTrue(SessionDate.isValidDate("15 aUg 2023")); // wrong case
+        assertTrue(SessionDate.isValidDate("4 fEB 1989")); //both
     }
 
     @Test
     public void equals() {
-        SessionDate sessionDate = new SessionDate("24 Sep 2024");
+        SessionDate sessionDate = new SessionDate("4 Sep 2024");
 
         // same values -> returns true
-        assertTrue(sessionDate.equals(new SessionDate("24 Sep 2024")));
+        assertTrue(sessionDate.equals(new SessionDate("4 Sep 2024")));
+
+        // same after formatting -> returns true
+        assertTrue(sessionDate.equals(new SessionDate("04 Sep 2024")));
+        assertTrue(sessionDate.equals(new SessionDate("4 sep 2024")));
+        assertTrue(sessionDate.equals(new SessionDate("4 SeP 2024")));
 
         // same object -> returns true
         assertTrue(sessionDate.equals(sessionDate));