Made new ReassignTaskCommand

docs/UserGuide.md

@@ -200,6 +200,16 @@ Format: `assign task/task title by/dd-MM-yyyy HHmm to/INDEX`
 Examples:
 * `assign task/Complete Project Proposal by/20-04-2024 2359 to/1` Assign the 'Complete Project Proposal' task to the first person in the address book.
 
+### Reassigning a task: `reassign`
+
+Reassign a specific task from one person to another.
+
+Format `reassign from/FROMINDEX to/TONDEX`
+
+* Assigns the task, which was previously assigned to person at the specified `FROMINDEX`, to the person at the specified `TOINDEX`
+* The index refers to the index number shown in the displayed employee list.
+* The index **must be a positive integer** 1, 2, 3, …​
+
 ### Marking a task : `mark`
 
 Mark the specified task as done.
@@ -286,6 +296,7 @@ Action     | Format, Examples
 **Delete** | `delete INDEX`<br> e.g., `delete 3`
 **Edit**   | `edit INDEX [n/NAME] [p/PHONE_NUMBER] [e/EMAIL] [a/ADDRESS] [d/DEPARTMENT] [t/TAG]…​`<br> e.g.,`edit 2 n/James Lee e/[email protected]`
 **Assign Task** | `assign task/TASK TITLE by/dd-MM-yyyy to/INDEX`<br> e.g., `assign task/Complete Project Proposal by/22-05-2023 2359 to/1`
+**Reassign Task** | `reassign from/FROMINDEX to/TOINDEX`<br> e.g., `reassign from/2 to/1`
 **Mark Task**   | `mark task/TASK o/INDEX` <br> e.g. `mark task/Complete Project Proposal o/1`
 **Find**   | `find KEYWORD [MORE_KEYWORDS]`<br> e.g., `find James Jake`
 **List**   | `list`

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

@@ -53,7 +53,7 @@ public CommandResult execute(Model model, CommandHistory history) throws Command
         requireNonNull(model);
         List<Person> personList = model.getFilteredPersonList();
 
-        if (index.getOneBased() >= personList.size()) {
+        if (index.getZeroBased() >= personList.size()) {
             throw new CommandException(Messages.MESSAGE_INVALID_PERSON_DISPLAYED_INDEX);
         }
 

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

@@ -0,0 +1,95 @@
+package seedu.address.logic.commands;
+
+import static java.util.Objects.requireNonNull;
+import static seedu.address.commons.util.CollectionUtil.requireAllNonNull;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_FROM;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_TO;
+
+import java.util.List;
+
+import seedu.address.commons.core.index.Index;
+import seedu.address.logic.CommandHistory;
+import seedu.address.logic.Messages;
+import seedu.address.logic.commands.exceptions.CommandException;
+import seedu.address.model.Model;
+import seedu.address.model.person.Person;
+import seedu.address.model.task.Task;
+
+/**
+ * Reassigns task to another person
+ */
+public class ReassignTaskCommand extends Command {
+
+    public static final String COMMAND_WORD = "reassign";
+
+    public static final String MESSAGE_REASSIGN_TASK_SUCCESS = "Reassigned task %1$s from %2$s to %3$s successfully";
+
+    public static final String MESSAGE_USAGE = COMMAND_WORD
+            + ": Reassigns a task to a person identified by index number.\n"
+            + "Parameters: "
+            + PREFIX_FROM + "INDEX (must be a positive integer) "
+            + PREFIX_TO + "INDEX (must be a positive integer)\n"
+            + "Example: " + COMMAND_WORD + " "
+            + PREFIX_FROM + "2 "
+            + PREFIX_TO + "1";
+    public static final String MESSAGE_PERSON_IS_BUSY = "A task has already been assigned for %1$s. "
+            + "Please select another person.";
+    public static final String MESSAGE_TASK_DOES_NOT_EXIST = "%s has not been assigned a task. "
+            + "Please select another Task";
+    private final Index fromIndex;
+    private final Index toIndex;
+
+    /**
+     * Reassigns a task from one person to another.
+     * @param fromIndex
+     * @param toIndex
+     */
+    public ReassignTaskCommand(Index fromIndex, Index toIndex) {
+        requireAllNonNull(fromIndex, toIndex);
+        this.fromIndex = fromIndex;
+        this.toIndex = toIndex;
+    }
+
+    @Override
+    public CommandResult execute(Model model, CommandHistory commandHistory) throws CommandException {
+        requireNonNull(model);
+        List<Person> personList = model.getFilteredPersonList();
+
+        if ((fromIndex.getZeroBased() >= personList.size() || toIndex.getZeroBased() >= personList.size())) {
+            throw new CommandException(Messages.MESSAGE_INVALID_PERSON_DISPLAYED_INDEX);
+        }
+
+        Person assignedFrom = personList.get(fromIndex.getZeroBased());
+        Person assignedTo = personList.get(toIndex.getZeroBased());
+
+        if (assignedTo.isBusy()) {
+            throw new CommandException(String.format(MESSAGE_PERSON_IS_BUSY, Messages.printName(assignedTo)));
+        }
+        Task task = assignedFrom.getTask();
+        if (task == null) {
+            throw new CommandException(String.format(MESSAGE_TASK_DOES_NOT_EXIST, Messages.printName(assignedFrom)));
+        }
+
+        model.reassignTask(task, assignedFrom, assignedTo);
+        model.commitAddressBook();
+
+        return new CommandResult(String.format(MESSAGE_REASSIGN_TASK_SUCCESS,
+                Messages.printTask(task), Messages.printName(assignedFrom), Messages.printName(assignedTo)));
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        if (other == this) {
+            return true;
+        }
+
+        // instanceof handles nulls
+        if (!(other instanceof ReassignTaskCommand)) {
+            return false;
+        }
+
+        ReassignTaskCommand otherReassignCommand = (ReassignTaskCommand) other;
+        return fromIndex.equals(otherReassignCommand.fromIndex)
+                && toIndex.equals(otherReassignCommand.toIndex);
+    }
+}

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

@@ -23,6 +23,7 @@
 import seedu.address.logic.commands.HistoryCommand;
 import seedu.address.logic.commands.ListCommand;
 import seedu.address.logic.commands.MarkTaskCommand;
+import seedu.address.logic.commands.ReassignTaskCommand;
 import seedu.address.logic.commands.RedoCommand;
 import seedu.address.logic.commands.UndoCommand;
 import seedu.address.logic.parser.exceptions.ParseException;
@@ -106,10 +107,12 @@ public Command parseCommand(String userInput) throws ParseException {
         case FilterEfficiencyCommand.COMMAND_WORD:
             return new FilterEfficiencyCommandParser().parse(arguments);
 
+        case ReassignTaskCommand.COMMAND_WORD:
+            return new ReassignTaskCommandParser().parse(arguments);
+
         case EditDeadlineCommand.COMMAND_WORD:
             return new EditDeadlineCommandParser().parse(arguments);
 
-
         default:
             logger.finer("This user input caused a ParseException: " + userInput);
             throw new ParseException(MESSAGE_UNKNOWN_COMMAND);

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

@@ -15,6 +15,7 @@ public class CliSyntax {
     public static final Prefix PREFIX_TASK = new Prefix("task/");
     public static final Prefix PREFIX_DEADLINE = new Prefix("by/");
     public static final Prefix PREFIX_TO = new Prefix("to/");
+    public static final Prefix PREFIX_FROM = new Prefix("from/");
     public static final Prefix PREFIX_EFFICIENCY = new Prefix("eff/");
     public static final Prefix PREFIX_TASK_OWNER = new Prefix("o/");
 

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

@@ -0,0 +1,37 @@
+package seedu.address.logic.parser;
+
+import static seedu.address.logic.Messages.MESSAGE_INVALID_COMMAND_FORMAT;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_FROM;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_TO;
+
+import java.util.stream.Stream;
+
+import seedu.address.commons.core.index.Index;
+import seedu.address.logic.commands.ReassignTaskCommand;
+import seedu.address.logic.parser.exceptions.ParseException;
+
+/**
+ * Parse input arguments and create a new ReassignTaskCommand object.
+ */
+public class ReassignTaskCommandParser implements Parser<ReassignTaskCommand> {
+
+    @Override
+    public ReassignTaskCommand parse(String userInput) throws ParseException {
+        ArgumentMultimap argMultimap = ArgumentTokenizer.tokenize(userInput, PREFIX_FROM, PREFIX_TO);
+
+        if (!arePrefixesPresent(argMultimap, PREFIX_FROM, PREFIX_TO)
+                || !argMultimap.getPreamble().isEmpty()) {
+            throw new ParseException(String.format(MESSAGE_INVALID_COMMAND_FORMAT, ReassignTaskCommand.MESSAGE_USAGE));
+        }
+        Index fromIndex = ParserUtil.parseIndex(argMultimap.getValue(PREFIX_FROM).get());
+        Index toIndex = ParserUtil.parseIndex(argMultimap.getValue(PREFIX_TO).get());
+
+        return new ReassignTaskCommand(fromIndex, toIndex);
+
+    }
+
+    private static boolean arePrefixesPresent(ArgumentMultimap argumentMultimap, Prefix... prefixes) {
+        return Stream.of(prefixes).allMatch(prefix -> argumentMultimap.getValue(prefix).isPresent());
+    }
+
+}

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

@@ -166,6 +166,16 @@ public void assignTask(Task task, Person pic) {
         indicateModified();
     }
 
+    /**
+     * Reassigns a task from one person to another person.
+     */
+    public void reassignTask(Task task, Person oldPic, Person pic) {
+        task.setPersonInCharge(pic);
+        pic.setTask(task);
+        oldPic.setTask(null);
+        indicateModified();
+    }
+
     /**
      * Marks an assigned task as done.
      */

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

@@ -102,6 +102,11 @@ public interface Model {
      */
     void assignTask(Task task, Person person);
 
+    /**
+     * Reassigns task from one person to another.
+     */
+    void reassignTask(Task task, Person assignedFrom, Person assignedTo);
+
     /**
      * Marks an assigned task as done.
      */

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

@@ -132,6 +132,13 @@ public void assignTask(Task task, Person assignedTo) {
         versionedAddressBook.assignTask(task, assignedTo);
     }
 
+    @Override
+    public void reassignTask(Task task, Person assignedFrom, Person assignedTo) {
+        requireAllNonNull(task, assignedFrom, assignedTo);
+        versionedAddressBook.reassignTask(task, assignedFrom, assignedTo);
+
+    }
+
     @Override
     public void markTask(Task task) {
         requireNonNull(task);

src/test/java/seedu/address/logic/commands/AddCommandTest.java

@@ -179,6 +179,11 @@ public void assignTask(Task task, Person person) {
             throw new AssertionError("This method should not be called.");
         }
 
+        @Override
+        public void reassignTask(Task task, Person assignedFrom, Person assignedTo) {
+            throw new AssertionError("This method should not be called.");
+        }
+
         @Override
         public void markTask(Task task) {
             throw new AssertionError("This method should not be called.");

src/test/java/seedu/address/logic/commands/MarkTaskCommandTest.java

@@ -0,0 +1,13 @@
+package seedu.address.logic.commands;
+
+import static seedu.address.testutil.Assert.assertThrows;
+
+import org.junit.jupiter.api.Test;
+
+public class MarkTaskCommandTest {
+
+    @Test
+    public void constructor_nullTask_throwsNullPointerException() {
+        assertThrows(NullPointerException.class, () -> new MarkTaskCommand(null, null));
+    }
+}

src/test/java/seedu/address/logic/commands/ReassignTaskCommandTest.java

@@ -0,0 +1,12 @@
+package seedu.address.logic.commands;
+
+import static seedu.address.testutil.Assert.assertThrows;
+
+import org.junit.jupiter.api.Test;
+
+public class ReassignTaskCommandTest {
+    @Test
+    public void constructor_nullTask_throwsNullPointerException() {
+        assertThrows(NullPointerException.class, () -> new ReassignTaskCommand(null, null));
+    }
+}