Contacts assigned and tasks assigned commands (#113)

* Add predicates for assignment of tasks and persons

* Change select command to assigned command

* Add assigned command for tasks

* Refactor and change equality operator to .equals

* Fix trailing whitespaces

* Fix wrong import order

* Fix lint

* Remove contacts select from user guide

* Fix and standardise line breaks in events

docs/UserGuide.adoc

@@ -72,12 +72,6 @@ Format:
 
 Format: `contacts find KEYWORD [MORE_KEYWORDS]`
 
-==== Select a contact: `contacts select`
-
-Format: `contacts select INDEX`
-
-Selects the contact identified by the index number used in the displayed contact list.
-
 ==== Delete contact: `contacts delete`
 
 Format: `contacts delete INDEX`
@@ -92,7 +86,7 @@ Format: `contacts assign c/CONTACT_INDEX k/TASK_INDEX`
 Format: `contacts unassign c/CONTACT_INDEX k/TASK_INDEX`
 // end::assigntasktocontact[]
 
-==== Show tasks assigned to contact:
+==== Show tasks assigned to contact: `contacts assigned`
 
 Format: `contacts assigned CONTACT_ID`
 

src/main/java/seedu/address/commons/events/ui/CalendarPanelClickEvent.java

@@ -6,6 +6,7 @@
  * Represents a click event in the Calendar Panel
  */
 public class CalendarPanelClickEvent extends TaskPanelSelectionChangedEvent {
+
     public CalendarPanelClickEvent(Task newSelection) {
         super(newSelection);
     }

src/main/java/seedu/address/commons/events/ui/JumpToPersonListRequestEvent.java

@@ -18,5 +18,4 @@ public JumpToPersonListRequestEvent(Index targetIndex) {
     public String toString() {
         return getClass().getSimpleName();
     }
-
 }

src/main/java/seedu/address/commons/events/ui/JumpToTaskListRequestEvent.java

@@ -18,5 +18,4 @@ public JumpToTaskListRequestEvent(Index targetIndex) {
     public String toString() {
         return getClass().getSimpleName();
     }
-
 }

src/main/java/seedu/address/commons/events/ui/NewResultAvailableEvent.java

@@ -17,5 +17,4 @@ public NewResultAvailableEvent(String message) {
     public String toString() {
         return getClass().getSimpleName();
     }
-
 }

src/main/java/seedu/address/commons/events/ui/PersonPanelDeselectionEvent.java

@@ -0,0 +1,14 @@
+package seedu.address.commons.events.ui;
+
+import seedu.address.commons.events.BaseEvent;
+
+/**
+ * Represents a deselection in the Person List Panel
+ */
+public class PersonPanelDeselectionEvent extends BaseEvent {
+
+    @Override
+    public String toString() {
+        return getClass().getSimpleName();
+    }
+}

src/main/java/seedu/address/commons/events/ui/PersonPanelSelectionChangedEvent.java

@@ -8,7 +8,6 @@
  */
 public class PersonPanelSelectionChangedEvent extends BaseEvent {
 
-
     private final Person newSelection;
 
     public PersonPanelSelectionChangedEvent(Person newSelection) {

src/main/java/seedu/address/commons/events/ui/ShowHelpRequestEvent.java

@@ -11,5 +11,4 @@ public class ShowHelpRequestEvent extends BaseEvent {
     public String toString() {
         return getClass().getSimpleName();
     }
-
 }

src/main/java/seedu/address/commons/events/ui/TaskPanelDeselectionEvent.java

@@ -6,9 +6,9 @@
  * Represents a deselection in the Task List Panel
  */
 public class TaskPanelDeselectionEvent extends BaseEvent {
+
     @Override
     public String toString() {
         return getClass().getSimpleName();
     }
-
 }

src/main/java/seedu/address/commons/events/ui/TaskPanelSelectionChangedEvent.java

@@ -8,7 +8,6 @@
  */
 public class TaskPanelSelectionChangedEvent extends BaseEvent {
 
-
     private final Task newSelection;
 
     public TaskPanelSelectionChangedEvent(Task newSelection) {
@@ -23,5 +22,4 @@ public String toString() {
     public Task getNewSelection() {
         return newSelection;
     }
-
 }

src/main/java/seedu/address/logic/commands/contacts/SelectCommand.java → src/main/java/seedu/address/logic/commands/contacts/AssignedCommand.java

@@ -13,25 +13,28 @@
 import seedu.address.logic.commands.CommandResult;
 import seedu.address.logic.commands.exceptions.CommandException;
 import seedu.address.model.Model;
+import seedu.address.model.person.IsAssignedToPersonPredicate;
 import seedu.address.model.person.Person;
 
 /**
- * Selects a person identified using its displayed index from the address book.
+ * Selects a person identified using its displayed index,
+ * and the list of tasks will update to show only the tasks assigned to the person
  */
-public class SelectCommand extends Command {
+public class AssignedCommand extends Command {
 
-    public static final String COMMAND_WORD = "select";
+    public static final String COMMAND_WORD = "assigned";
 
     public static final String MESSAGE_USAGE = getCommandFormat(COMMAND_WORD)
-            + ": Selects the person identified by the index number used in the displayed person list.\n"
+            + ": Selects the person identified by the index number used in the displayed person "
+            + "list and shows the list of tasks assigned to the person.\n"
             + "Parameters: INDEX (must be a positive integer)\n"
             + "Example: " + getCommandFormat(COMMAND_WORD) + " 1";
 
     public static final String MESSAGE_SELECT_PERSON_SUCCESS = "Selected Person: %1$s";
 
     private final Index targetIndex;
 
-    public SelectCommand(Index targetIndex) {
+    public AssignedCommand(Index targetIndex) {
         this.targetIndex = targetIndex;
     }
 
@@ -44,7 +47,11 @@ public CommandResult execute(Model model, CommandHistory history) throws Command
         if (targetIndex.getZeroBased() >= filteredPersonList.size()) {
             throw new CommandException(Messages.MESSAGE_INVALID_PERSON_DISPLAYED_INDEX);
         }
+        // Retrieve the desired person and update filter
+        Person desiredPerson = filteredPersonList.get(targetIndex.getZeroBased());
+        model.updateFilteredTaskList(new IsAssignedToPersonPredicate(desiredPerson));
 
+        // Update UI (purely cosmetic for now)
         EventsCenter.getInstance().post(new JumpToPersonListRequestEvent(targetIndex));
         return new CommandResult(String.format(MESSAGE_SELECT_PERSON_SUCCESS, targetIndex.getOneBased()));
 
@@ -53,7 +60,7 @@ public CommandResult execute(Model model, CommandHistory history) throws Command
     @Override
     public boolean equals(Object other) {
         return other == this // short circuit if same object
-                || (other instanceof SelectCommand // instanceof handles nulls
-                && targetIndex.equals(((SelectCommand) other).targetIndex)); // state check
+                || (other instanceof AssignedCommand // instanceof handles nulls
+                && targetIndex.equals(((AssignedCommand) other).targetIndex)); // state check
     }
 }

src/main/java/seedu/address/logic/commands/tasks/AssignedCommand.java

@@ -0,0 +1,66 @@
+package seedu.address.logic.commands.tasks;
+
+import static java.util.Objects.requireNonNull;
+
+import java.util.List;
+
+import seedu.address.commons.core.EventsCenter;
+import seedu.address.commons.core.Messages;
+import seedu.address.commons.core.index.Index;
+import seedu.address.commons.events.ui.JumpToTaskListRequestEvent;
+import seedu.address.logic.CommandHistory;
+import seedu.address.logic.commands.Command;
+import seedu.address.logic.commands.CommandResult;
+import seedu.address.logic.commands.exceptions.CommandException;
+import seedu.address.model.Model;
+import seedu.address.model.task.IsAssignedToTaskPredicate;
+import seedu.address.model.task.Task;
+
+/**
+ * Selects a task identified using its displayed index,
+ * and the list of persons will update to show only the persons that are assigned to the task
+ */
+public class AssignedCommand extends Command {
+
+    public static final String COMMAND_WORD = "assigned";
+
+    public static final String MESSAGE_USAGE = getCommandFormat(COMMAND_WORD)
+            + ": Selects the task identified by the index number used in the displayed task "
+            + "list and shows the list of persons assigned to the task.\n"
+            + "Parameters: INDEX (must be a positive integer)\n"
+            + "Example: " + getCommandFormat(COMMAND_WORD) + " 1";
+
+    public static final String MESSAGE_SELECT_TASK_SUCCESS = "Selected Task: %1$s";
+
+    private final Index targetIndex;
+
+    public AssignedCommand(Index targetIndex) {
+        this.targetIndex = targetIndex;
+    }
+
+    @Override
+    public CommandResult execute(Model model, CommandHistory history) throws CommandException {
+        requireNonNull(model);
+
+        List<Task> filteredTaskList = model.getFilteredTaskList();
+
+        if (targetIndex.getZeroBased() >= filteredTaskList.size()) {
+            throw new CommandException(Messages.MESSAGE_INVALID_TASK_DISPLAYED_INDEX);
+        }
+        // Retrieve the desired task and update filter
+        Task desiredTask = filteredTaskList.get(targetIndex.getZeroBased());
+        model.updateFilteredPersonList(new IsAssignedToTaskPredicate(desiredTask));
+
+        // Update UI (purely cosmetic for now)
+        EventsCenter.getInstance().post(new JumpToTaskListRequestEvent(targetIndex));
+        return new CommandResult(String.format(MESSAGE_SELECT_TASK_SUCCESS, targetIndex.getOneBased()));
+
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        return other == this // short circuit if same object
+                || (other instanceof AssignedCommand // instanceof handles nulls
+                && targetIndex.equals(((AssignedCommand) other).targetIndex)); // state check
+    }
+}

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

@@ -10,19 +10,19 @@
 import seedu.address.logic.commands.HelpCommand;
 import seedu.address.logic.commands.contacts.AddCommand;
 import seedu.address.logic.commands.contacts.AssignCommand;
+import seedu.address.logic.commands.contacts.AssignedCommand;
 import seedu.address.logic.commands.contacts.ClearCommand;
 import seedu.address.logic.commands.contacts.DeleteCommand;
 import seedu.address.logic.commands.contacts.EditCommand;
 import seedu.address.logic.commands.contacts.FindCommand;
 import seedu.address.logic.commands.contacts.ListCommand;
-import seedu.address.logic.commands.contacts.SelectCommand;
 import seedu.address.logic.commands.contacts.UnassignCommand;
 import seedu.address.logic.parser.contacts.AddCommandParser;
 import seedu.address.logic.parser.contacts.AssignCommandParser;
+import seedu.address.logic.parser.contacts.AssignedCommandParser;
 import seedu.address.logic.parser.contacts.DeleteCommandParser;
 import seedu.address.logic.parser.contacts.EditCommandParser;
 import seedu.address.logic.parser.contacts.FindCommandParser;
-import seedu.address.logic.parser.contacts.SelectCommandParser;
 import seedu.address.logic.parser.contacts.UnassignCommandParser;
 import seedu.address.logic.parser.exceptions.ParseException;
 
@@ -62,8 +62,8 @@ public Command parseCommand(String userInput) throws ParseException {
             case EditCommand.COMMAND_WORD:
                 return new EditCommandParser().parse(arguments);
 
-            case SelectCommand.COMMAND_WORD:
-                return new SelectCommandParser().parse(arguments);
+            case AssignedCommand.COMMAND_WORD:
+                return new AssignedCommandParser().parse(arguments);
 
             case DeleteCommand.COMMAND_WORD:
                 return new DeleteCommandParser().parse(arguments);

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

@@ -10,6 +10,7 @@
 import seedu.address.logic.commands.HelpCommand;
 import seedu.address.logic.commands.tasks.AddCommand;
 import seedu.address.logic.commands.tasks.AssignCommand;
+import seedu.address.logic.commands.tasks.AssignedCommand;
 import seedu.address.logic.commands.tasks.DeleteCommand;
 import seedu.address.logic.commands.tasks.EditCommand;
 import seedu.address.logic.commands.tasks.FindCommand;
@@ -19,6 +20,7 @@
 import seedu.address.logic.parser.exceptions.ParseException;
 import seedu.address.logic.parser.tasks.AddCommandParser;
 import seedu.address.logic.parser.tasks.AssignCommandParser;
+import seedu.address.logic.parser.tasks.AssignedCommandParser;
 import seedu.address.logic.parser.tasks.DeleteCommandParser;
 import seedu.address.logic.parser.tasks.EditCommandParser;
 import seedu.address.logic.parser.tasks.FindCommandParser;
@@ -61,6 +63,9 @@ public Command parseCommand(String userInput) throws ParseException {
             case EditCommand.COMMAND_WORD:
                 return new EditCommandParser().parse(arguments);
 
+            case AssignedCommand.COMMAND_WORD:
+                return new AssignedCommandParser().parse(arguments);
+
             case DeleteCommand.COMMAND_WORD:
                 return new DeleteCommandParser().parse(arguments);
 

src/main/java/seedu/address/logic/parser/contacts/SelectCommandParser.java → src/main/java/seedu/address/logic/parser/contacts/AssignedCommandParser.java

@@ -3,27 +3,27 @@
 import static seedu.address.commons.core.Messages.MESSAGE_INVALID_COMMAND_FORMAT;
 
 import seedu.address.commons.core.index.Index;
-import seedu.address.logic.commands.contacts.SelectCommand;
+import seedu.address.logic.commands.contacts.AssignedCommand;
 import seedu.address.logic.parser.Parser;
 import seedu.address.logic.parser.exceptions.ParseException;
 
 /**
- * Parses input arguments and creates a new SelectCommand object
+ * Parses input arguments and creates a new AssignedCommand object
  */
-public class SelectCommandParser implements Parser<SelectCommand> {
+public class AssignedCommandParser implements Parser<AssignedCommand> {
 
     /**
-     * Parses the given {@code String} of arguments in the context of the SelectCommand
-     * and returns an SelectCommand object for execution.
+     * Parses the given {@code String} of arguments in the context of the AssignedCommand
+     * and returns an AssignedCommand object for execution.
      * @throws ParseException if the user input does not conform the expected format
      */
-    public SelectCommand parse(String args) throws ParseException {
+    public AssignedCommand parse(String args) throws ParseException {
         try {
             Index index = ParserUtil.parseIndex(args);
-            return new SelectCommand(index);
+            return new AssignedCommand(index);
         } catch (ParseException pe) {
             throw new ParseException(
-                    String.format(MESSAGE_INVALID_COMMAND_FORMAT, SelectCommand.MESSAGE_USAGE), pe, true);
+                    String.format(MESSAGE_INVALID_COMMAND_FORMAT, AssignedCommand.MESSAGE_USAGE), pe, true);
         }
     }
 }

src/main/java/seedu/address/logic/parser/tasks/AssignedCommandParser.java

@@ -0,0 +1,30 @@
+package seedu.address.logic.parser.tasks;
+
+import static seedu.address.commons.core.Messages.MESSAGE_INVALID_COMMAND_FORMAT;
+
+import seedu.address.commons.core.index.Index;
+import seedu.address.logic.commands.tasks.AssignedCommand;
+import seedu.address.logic.parser.Parser;
+import seedu.address.logic.parser.contacts.ParserUtil;
+import seedu.address.logic.parser.exceptions.ParseException;
+
+/**
+ * Parses input arguments and creates a new AssignedCommand object
+ */
+public class AssignedCommandParser implements Parser<AssignedCommand> {
+
+    /**
+     * Parses the given {@code String} of arguments in the context of the AssignedCommand
+     * and returns an AssignedCommand object for execution.
+     * @throws ParseException if the user input does not conform the expected format
+     */
+    public AssignedCommand parse(String args) throws ParseException {
+        try {
+            Index index = ParserUtil.parseIndex(args);
+            return new AssignedCommand(index);
+        } catch (ParseException pe) {
+            throw new ParseException(
+                    String.format(MESSAGE_INVALID_COMMAND_FORMAT, AssignedCommand.MESSAGE_USAGE), pe, true);
+        }
+    }
+}

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

@@ -0,0 +1,30 @@
+package seedu.address.model.person;
+
+import java.util.function.Predicate;
+
+import seedu.address.model.task.Task;
+
+/**
+ * Tests that a {@code Task} is assigned to the desired person (i.e. task contains id of {@code Person})
+ */
+public class IsAssignedToPersonPredicate implements Predicate<Task> {
+    private final Person person;
+
+    public IsAssignedToPersonPredicate(Person person) {
+        this.person = person;
+    }
+
+    @Override
+    public boolean test(Task task) {
+        return task.getPersonIds().stream()
+                .anyMatch(personId -> person.getId().equals(personId));
+    }
+
+    @Override
+    public boolean equals(Object other) {
+        return other == this // short circuit if same object
+                || (other instanceof IsAssignedToPersonPredicate // instanceof handles nulls
+                && person.equals(((IsAssignedToPersonPredicate) other).person)); // state check
+    }
+
+}