Trim whitespaces and improve storage reading

build.gradle

@@ -35,7 +35,7 @@ application {
 shadowJar {
     archiveBaseName = "convobot"
     archiveClassifier = null
-    dependsOn("distZip", "distTar")
+    dependsOn("distZip", "distTar");
 }
 
 // Configure run task settings

src/main/java/cvb/commands/CommandParser.java

@@ -37,6 +37,7 @@ private static void enforceArgumentCount(int a, int b) throws ConvoBotException
      * @throws ConvoBotException if the input is invalid or cannot be parsed
      */
     public static Command parse(String userInput) throws ConvoBotException {
+        userInput = userInput.trim(); // remove leading and trailing spaces
         ArrayList<String> inputList = new ArrayList<>(Arrays.asList(userInput.split(" ")));
         if (inputList.isEmpty()) {
             throw new ConvoBotException("Invalid input. Input must not be empty.");

src/main/java/cvb/tasks/TaskParser.java

@@ -21,6 +21,7 @@ public static Task parse(String line) throws IllegalArgumentException {
         final IllegalArgumentException invalidLineException =
                 new IllegalArgumentException("Invalid line format: " + line);
 
+        line = line.trim(); // remove leading and trailing spaces
         String[] parts = line.split(" \\| ");
         if (parts.length < minPartsLength || parts.length > maxPartsLength) {
             throw invalidLineException;

src/main/java/cvb/utils/Storage.java

@@ -39,12 +39,17 @@ public ArrayList<Task> read() {
             BufferedReader reader = new BufferedReader(new FileReader(filePath));
             String line;
             while ((line = reader.readLine()) != null) {
-                Task task = TaskParser.parse(line);
+                Task task;
+                try {
+                    task = TaskParser.parse(line);
+                } catch (IllegalArgumentException e) {
+                    continue; // skip this line
+                }
                 taskList.add(task);
             }
             reader.close();
         } catch (IOException e) {
-            // ignored as taskList will be returned empty
+            return taskList;
         }
         return taskList;
     }