Add undo redo

src/main/java/seedu/address/logic/LogicManager.java

@@ -48,7 +48,7 @@ public CommandResult execute(String commandText) throws CommandException, ParseE
 
         CommandResult commandResult;
         Command command = addressBookParser.parseCommand(commandText);
-        commandResult = command.execute(model);
+        commandResult = command.execute(model, commandText);
 
         try {
             storage.saveAddressBook(model.getAddressBook());

src/main/java/seedu/address/logic/commands/AddCommand.java

@@ -57,14 +57,15 @@ public AddCommand(Person person) {
     }
 
     @Override
-    public CommandResult execute(Model model) throws CommandException {
+    public CommandResult execute(Model model, String commandText) throws CommandException {
         requireNonNull(model);
 
         if (model.hasPerson(toAdd)) {
             throw new CommandException(MESSAGE_DUPLICATE_PERSON);
         }
 
         model.addPerson(toAdd);
+        model.addCommandText(commandText);
         return new CommandResult(String.format(MESSAGE_SUCCESS, Messages.format(toAdd)));
     }
 

src/main/java/seedu/address/logic/commands/BirthdayCommand.java

@@ -35,7 +35,7 @@ public Predicate<Person> getPredicate() {
     }
 
     @Override
-    public CommandResult execute(Model model) {
+    public CommandResult execute(Model model, String commandText) {
         requireNonNull(model);
         model.updateFilteredPersonList(predicate);
         if (model.getFilteredPersonList().isEmpty()) {

src/main/java/seedu/address/logic/commands/ClaimCommand.java

@@ -51,7 +51,7 @@ public ClaimCommand(Index index, Boolean isSubtract, long amount) {
      * @throws CommandException Exception thrown if index input from HR is beyond the pre-existing max list index.
      */
     @Override
-    public CommandResult execute(Model model) throws CommandException {
+    public CommandResult execute(Model model, String commandText) throws CommandException {
         requireNonNull(model);
         List<Person> lastShownList = model.getFilteredPersonList();
 
@@ -65,6 +65,7 @@ public CommandResult execute(Model model) throws CommandException {
         Person editedPerson = postClaimPerson(personToEdit, claimBudget);
 
         model.setPerson(personToEdit, editedPerson);
+        model.addCommandText(commandText);
         model.updateFilteredPersonList(PREDICATE_SHOW_ALL_PERSONS);
 
         return new CommandResult(String.format("%s Remaining claim %s has: %s",

src/main/java/seedu/address/logic/commands/ClearCommand.java

@@ -15,9 +15,10 @@ public class ClearCommand extends Command {
 
 
     @Override
-    public CommandResult execute(Model model) {
+    public CommandResult execute(Model model, String commandText) {
         requireNonNull(model);
         model.setAddressBook(new AddressBook());
+        model.addCommandText(commandText);
         return new CommandResult(MESSAGE_SUCCESS);
     }
 }

src/main/java/seedu/address/logic/commands/Command.java

@@ -15,6 +15,6 @@ public abstract class Command {
      * @return feedback message of the operation result for display
      * @throws CommandException If an error occurs during command execution.
      */
-    public abstract CommandResult execute(Model model) throws CommandException;
+    public abstract CommandResult execute(Model model, String commandText) throws CommandException;
 
 }

src/main/java/seedu/address/logic/commands/DeleteCommand.java

@@ -32,7 +32,7 @@ public DeleteCommand(Index targetIndex) {
     }
 
     @Override
-    public CommandResult execute(Model model) throws CommandException {
+    public CommandResult execute(Model model, String commandText) throws CommandException {
         requireNonNull(model);
         List<Person> lastShownList = model.getFilteredPersonList();
 
@@ -42,6 +42,7 @@ public CommandResult execute(Model model) throws CommandException {
 
         Person personToDelete = lastShownList.get(targetIndex.getZeroBased());
         model.deletePerson(personToDelete);
+        model.addCommandText(commandText);
         return new CommandResult(String.format(MESSAGE_DELETE_PERSON_SUCCESS, personToDelete.getName()));
     }
 

src/main/java/seedu/address/logic/commands/EditCommand.java

@@ -73,7 +73,7 @@ public EditCommand(Index index, EditPersonDescriptor editPersonDescriptor) {
     }
 
     @Override
-    public CommandResult execute(Model model) throws CommandException {
+    public CommandResult execute(Model model, String commandText) throws CommandException {
         requireNonNull(model);
         List<Person> lastShownList = model.getFilteredPersonList();
 
@@ -89,6 +89,7 @@ public CommandResult execute(Model model) throws CommandException {
         }
 
         model.setPerson(personToEdit, editedPerson);
+        model.addCommandText(commandText);
         model.updateFilteredPersonList(PREDICATE_SHOW_ALL_PERSONS);
         return new CommandResult(String.format(MESSAGE_EDIT_PERSON_SUCCESS, Messages.format(editedPerson)));
     }

src/main/java/seedu/address/logic/commands/ExitCommand.java

@@ -12,7 +12,7 @@ public class ExitCommand extends Command {
     public static final String MESSAGE_EXIT_ACKNOWLEDGEMENT = "Exiting Address Book as requested ...";
 
     @Override
-    public CommandResult execute(Model model) {
+    public CommandResult execute(Model model, String commandText) {
         return new CommandResult(MESSAGE_EXIT_ACKNOWLEDGEMENT, false, true);
     }
 

src/main/java/seedu/address/logic/commands/FindCommand.java

@@ -27,7 +27,7 @@ public FindCommand(NameContainsKeywordsPredicate predicate) {
     }
 
     @Override
-    public CommandResult execute(Model model) {
+    public CommandResult execute(Model model, String commandText) {
         requireNonNull(model);
         model.updateFilteredPersonList(predicate);
         return new CommandResult(

src/main/java/seedu/address/logic/commands/HelpCommand.java

@@ -15,7 +15,7 @@ public class HelpCommand extends Command {
     public static final String SHOWING_HELP_MESSAGE = "Opened help window.";
 
     @Override
-    public CommandResult execute(Model model) {
+    public CommandResult execute(Model model, String commandText) {
         return new CommandResult(SHOWING_HELP_MESSAGE, true, false);
     }
 }

src/main/java/seedu/address/logic/commands/LeaveCommand.java

@@ -56,7 +56,7 @@ public LeaveCommand(Index index, String change) {
     }
 
     @Override
-    public CommandResult execute(Model model) throws CommandException {
+    public CommandResult execute(Model model, String commandText) throws CommandException {
         requireNonNull(model);
         List<Person> lastShownList = model.getFilteredPersonList();
 
@@ -82,6 +82,7 @@ public CommandResult execute(Model model) throws CommandException {
                 oldPerson.getDepartment(), oldPerson.getDob(), newLeave);
 
         model.setPerson(oldPerson, newPerson);
+        model.addCommandText(commandText);
         model.updateFilteredPersonList(PREDICATE_SHOW_ALL_PERSONS);
         return new CommandResult(String.format(MESSAGE_LEAVE_SUCCESS, newPerson.getName(), newLeave.toString()));
     }

src/main/java/seedu/address/logic/commands/ListCommand.java

@@ -39,7 +39,7 @@ public ListCommand(Predicate<Person> predicate) {
     }
 
     @Override
-    public CommandResult execute(Model model) {
+    public CommandResult execute(Model model, String commandText) {
         requireNonNull(model);
         model.updateFilteredPersonList(predicate);
         return new CommandResult(String.format(message, model.getFilteredPersonList().size()));

src/main/java/seedu/address/logic/commands/RedoCommand.java

@@ -0,0 +1,34 @@
+package seedu.address.logic.commands;
+
+import static java.util.Objects.requireNonNull;
+import static seedu.address.model.Model.PREDICATE_SHOW_ALL_PERSONS;
+
+import seedu.address.logic.commands.exceptions.CommandException;
+import seedu.address.model.Model;
+
+/**
+ * Redo the most recent command that was undone.
+ */
+public class RedoCommand extends Command {
+
+    public static final String COMMAND_WORD = "redo";
+
+    public static final String MESSAGE_USAGE = COMMAND_WORD
+            + ": Redo the most recent command that was undone.";
+
+    private static final String MESSAGE_SUCCESS = 
+            "The last command that modified the employee list has been redone!\n"
+            + "Successfully redone the following command: %1$s";
+
+    @Override
+    public CommandResult execute(Model model, String cmd) throws CommandException {
+        requireNonNull(model);
+        try {
+            String commandText = model.redo();
+            model.updateFilteredPersonList(PREDICATE_SHOW_ALL_PERSONS);
+            return new CommandResult(String.format(MESSAGE_SUCCESS, commandText));
+        } catch (IllegalArgumentException e) {
+            throw new CommandException(e.getMessage());
+        }
+    }
+}

src/main/java/seedu/address/logic/commands/UndoCommand.java

@@ -0,0 +1,34 @@
+package seedu.address.logic.commands;
+
+import static java.util.Objects.requireNonNull;
+import static seedu.address.model.Model.PREDICATE_SHOW_ALL_PERSONS;
+
+import seedu.address.logic.commands.exceptions.CommandException;
+import seedu.address.model.Model;
+
+/**
+ * Undo the most recent command that modified the employee list.
+ */
+public class UndoCommand extends Command {
+
+    public static final String COMMAND_WORD = "undo";
+
+    public static final String MESSAGE_USAGE = COMMAND_WORD
+            + ": Undo the most recent command that modified the employee list.";
+
+    private static final String MESSAGE_SUCCESS = 
+            "The last command that modified the employee list has been undone!\n"
+            + "Successfully undone the following command: %1$s";
+
+    @Override
+    public CommandResult execute(Model model, String cmd) throws CommandException {
+        requireNonNull(model);
+        try {
+            String commandText = model.undo();
+            model.updateFilteredPersonList(PREDICATE_SHOW_ALL_PERSONS);
+            return new CommandResult(String.format(MESSAGE_SUCCESS, commandText));
+        } catch (IllegalArgumentException e) {
+            throw new CommandException(e.getMessage());
+        }
+    }
+}

src/main/java/seedu/address/logic/commands/ViewCommand.java

@@ -53,7 +53,7 @@ public ViewCommand(HashMap<String, List<Index>> references) {
      * @throws CommandException Exception thrown if index input from HR is beyond the pre-existing max list index.
      */
     @Override
-    public CommandResult execute(Model model) throws CommandException {
+    public CommandResult execute(Model model, String commandText) throws CommandException {
         requireNonNull(model);
         List<Person> lastShownList = model.getFilteredPersonList();
 

src/main/java/seedu/address/logic/commands/ViewLeaveCommand.java

@@ -29,7 +29,7 @@ public ViewLeaveCommand(Predicate<Person> combinedPredicate) {
     }
 
     @Override
-    public CommandResult execute(Model model) throws CommandException {
+    public CommandResult execute(Model model, String commandText) throws CommandException {
         requireNonNull(model);
         model.updateFilteredPersonList(combinedPredicate);
         return new CommandResult(String.format(MESSAGE, model.getFilteredPersonList().size()));

src/main/java/seedu/address/logic/parser/AddressBookParser.java

@@ -20,6 +20,8 @@
 import seedu.address.logic.commands.HelpCommand;
 import seedu.address.logic.commands.LeaveCommand;
 import seedu.address.logic.commands.ListCommand;
+import seedu.address.logic.commands.RedoCommand;
+import seedu.address.logic.commands.UndoCommand;
 import seedu.address.logic.commands.ViewCommand;
 import seedu.address.logic.commands.ViewLeaveCommand;
 import seedu.address.logic.parser.exceptions.ParseException;
@@ -95,6 +97,13 @@ public Command parseCommand(String userInput) throws ParseException {
 
         case BirthdayCommand.COMMAND_WORD:
             return new BirthdayCommandParser().parse(arguments);
+
+        case UndoCommand.COMMAND_WORD:
+            return new UndoCommand();
+
+        case RedoCommand.COMMAND_WORD:
+            return new RedoCommand();
+
         default:
             logger.finer("This user input caused a ParseException: " + userInput);
             throw new ParseException(MESSAGE_UNKNOWN_COMMAND);

src/main/java/seedu/address/model/AddressBookList.java

@@ -0,0 +1,60 @@
+package seedu.address.model;
+
+import static seedu.address.commons.util.AppUtil.checkArgument;
+
+import java.util.ArrayList;
+
+public class AddressBookList extends ArrayList<AddressBook> {
+    private static final String REDO_ERROR_MESSAGE = "There is no command to redo! "
+            + "The command to be redone need to previously modified the employee list.";
+    private static final String UNDO_ERROR_MESSAGE = "There is no command to undo! "
+            + "The command to be undone need to previously modified the employee list.";
+
+    private ArrayList<String> pastCommands = new ArrayList<String>();
+    private int index;
+
+    public AddressBookList() {
+        super();
+        index = -1;
+    }
+
+    @Override
+    public boolean add(AddressBook addressBook) {
+        index++;
+        if (index < this.size()) {
+            this.removeRange(index, this.size());
+            while (this.pastCommands.size() >= index) {
+                this.pastCommands.remove(pastCommands.size() - 1);
+            }
+        }
+        return super.add(addressBook);
+    }
+
+    public AddressBook getAddressBook() {
+        return super.get(index);
+    }
+
+    public AddressBook undo() {
+        checkArgument(index > 0, UNDO_ERROR_MESSAGE);
+        index--;
+        return super.get(index);
+    }
+
+    public AddressBook redo() {
+        checkArgument(index < super.size() - 1, REDO_ERROR_MESSAGE);
+        index++;
+        return super.get(index);
+    }
+
+    public void addCommandText(String commandText) {
+        this.pastCommands.add(commandText);
+    }
+
+    public String undoPastCommand() {
+        return this.pastCommands.get(index);
+    }
+
+    public String redoPastCommand() {
+        return this.pastCommands.get(index - 1);
+    }
+}

src/main/java/seedu/address/model/Model.java

@@ -84,4 +84,10 @@ public interface Model {
      * @throws NullPointerException if {@code predicate} is null.
      */
     void updateFilteredPersonList(Predicate<Person> predicate);
+
+    String undo();
+
+    String redo();
+
+    void addCommandText(String commandText);
 }