Merge pull request nus-cs2103-AY2021S1#70 from successs404/branch-del…

…ete-grp

Branch delete grp

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

@@ -0,0 +1,58 @@
+package seedu.address.logic.commands;
+
+import static java.util.Objects.requireNonNull;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_GRP;
+
+import seedu.address.commons.core.Messages;
+import seedu.address.logic.commands.exceptions.CommandException;
+import seedu.address.model.Model;
+import seedu.address.model.group.Group;
+import seedu.address.model.group.GrpContainsKeywordPredicate;
+
+public class DelGrpCommand extends Command {
+
+    public static final String COMMAND_WORD = "delgrp";
+    public static final String MESSAGE_USAGE = COMMAND_WORD
+        + ": Deletes an existing tutorial group. "
+        + "Parameter: "
+        + PREFIX_GRP + "GRP \n"
+        + "Example: " + COMMAND_WORD + " " + PREFIX_GRP + "G04";
+
+    public static final String MESSAGE_DELETE_GROUP_SUCCESS = "Tutorial group deleted: %1$s";
+
+    private final GrpContainsKeywordPredicate grpPredicate;
+
+    /**
+     * Creates a DelGrpCommand to add the specified {@code Group}
+     */
+    public DelGrpCommand(GrpContainsKeywordPredicate grpPredicate) {
+        this.grpPredicate = grpPredicate;
+    }
+
+    @Override
+    public CommandResult execute(Model model) throws CommandException {
+        requireNonNull(model);
+
+        Group toDel = new Group();
+
+        boolean hasGroup = false;
+
+        if (!model.getSerenity().getGroupList().isEmpty()) {
+            for (Group group : model.getSerenity().getGroupList()) {
+                if (group.getName().equals(grpPredicate.getKeyword())) {
+                    toDel = group;
+                    hasGroup = true;
+                    break;
+                }
+            }
+        }
+
+        if (!hasGroup) {
+            throw new CommandException(Messages.MESSAGE_GROUP_EMPTY);
+        }
+
+        model.deleteGroup(toDel);
+        model.updateFilteredGroupList(grpPredicate);
+        return new CommandResult(String.format(MESSAGE_DELETE_GROUP_SUCCESS, toDel));
+    }
+}

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

@@ -0,0 +1,45 @@
+package seedu.address.logic.parser;
+
+import static seedu.address.commons.core.Messages.MESSAGE_INVALID_COMMAND_FORMAT;
+import static seedu.address.logic.parser.CliSyntax.PREFIX_GRP;
+
+import java.util.stream.Stream;
+
+import seedu.address.logic.commands.DelGrpCommand;
+import seedu.address.logic.parser.exceptions.ParseException;
+import seedu.address.model.group.GrpContainsKeywordPredicate;
+
+/**
+ * Parses input arguments and creates a new AddGrpCommand object
+ */
+public class DelGrpCommandParser implements Parser<DelGrpCommand> {
+
+    private final ParseException delGrpCommandParserException = new ParseException(
+        String.format(MESSAGE_INVALID_COMMAND_FORMAT, DelGrpCommand.MESSAGE_USAGE));
+
+    @Override
+    public DelGrpCommand parse(String args) throws ParseException {
+
+        ArgumentMultimap argMultimap = ArgumentTokenizer.tokenize(args, PREFIX_GRP);
+
+        if (!arePrefixesPresent(argMultimap, PREFIX_GRP) || !argMultimap.getPreamble().isEmpty()) {
+            throw delGrpCommandParserException;
+        }
+
+        String[] grpKeyword = argMultimap.getValue(PREFIX_GRP).get().split("\\s+");
+
+        if (grpKeyword.length > 1) {
+            throw delGrpCommandParserException;
+        }
+
+        return new DelGrpCommand(new GrpContainsKeywordPredicate(grpKeyword[0]));
+    }
+
+    /**
+     * Returns true if none of the prefixes contains empty {@code Optional} values in the given {@code
+     * ArgumentMultimap}.
+     */
+    private static boolean arePrefixesPresent(ArgumentMultimap argumentMultimap, Prefix... prefixes) {
+        return Stream.of(prefixes).allMatch(prefix -> argumentMultimap.getValue(prefix).isPresent());
+    }
+}

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

@@ -10,6 +10,7 @@
 import seedu.address.logic.commands.AddGrpCommand;
 import seedu.address.logic.commands.ClearCommand;
 import seedu.address.logic.commands.Command;
+import seedu.address.logic.commands.DelGrpCommand;
 import seedu.address.logic.commands.DeleteCommand;
 import seedu.address.logic.commands.EditCommand;
 import seedu.address.logic.commands.ExitCommand;
@@ -55,6 +56,9 @@ public Command parseCommand(String userInput) throws ParseException {
         case AddGrpCommand.COMMAND_WORD:
             return new AddGrpCommandParser().parse(arguments);
 
+        case DelGrpCommand.COMMAND_WORD:
+            return new DelGrpCommandParser().parse(arguments);
+
         case ViewGrpCommand.COMMAND_WORD:
             return new ViewGrpCommandParser().parse(arguments);
 

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

@@ -123,6 +123,11 @@ public interface Model {
      */
     boolean hasGroup(Group group);
 
+    /**
+     * Deletes the given group. The group must exist in serenity.
+     */
+    void deleteGroup(Group target);
+
     /**
      * Adds the given group. {@code group} must not already exist in serenity.
      */

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

@@ -186,6 +186,16 @@ public boolean hasGroup(Group group) {
         return serenity.hasGroup(group);
     }
 
+    @Override
+    public void deleteGroup(Group target) {
+        serenity.removeGroup(target);
+        filteredGroups.clear();
+        students.clear();
+        lessons.clear();
+        filteredLessons.clear();
+        studentsInfo.clear();
+    }
+
     @Override
     public void addGroup(Group group) {
         requireNonNull(group);

src/main/java/seedu/address/model/group/Group.java

@@ -25,6 +25,9 @@ public class Group {
     private UniqueStudentList students;
     private UniqueLessonList lessons;
 
+    // Empty constructor
+    public Group() {}
+
     /**
      * Constructs a {@code Group}
      *
@@ -61,14 +64,14 @@ public Group(String name, UniqueStudentList students) {
      *
      * @param name     A valid name.
      * @param students A list of students.
-     * @param lessons  A list of tutorial classes.
+     * @param lessons  A list of tutorial lessons.
      */
 
-    public Group(String name, UniqueStudentList students, UniqueLessonList classes) {
-        requireAllNonNull(name, students, classes);
+    public Group(String name, UniqueStudentList students, UniqueLessonList lessons) {
+        requireAllNonNull(name, students, lessons);
         this.name = name;
         this.students = students;
-        this.lessons = lessons;
+        this.lessons = this.lessons;
     }
 
     public String getName() {

src/main/java/seedu/address/model/group/GrpContainsKeywordPredicate.java

@@ -15,6 +15,10 @@ public GrpContainsKeywordPredicate(String string) {
         this.keyword = string;
     }
 
+    public String getKeyword() {
+        return keyword;
+    }
+
     @Override
     public boolean test(Group group) {
         return StringUtil.containsWordIgnoreCase(group.getName(), keyword);

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

@@ -179,6 +179,11 @@ public boolean hasGroup(Group group) {
             throw new AssertionError("This method should not be called.");
         }
 
+        @Override
+        public void deleteGroup(Group target) {
+            throw new AssertionError("This method should not be called.");
+        }
+
         @Override
         public void addGroup(Group group) {
             throw new AssertionError("This method should not be called.");

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

@@ -180,6 +180,11 @@ public boolean hasGroup(Group group) {
             throw new AssertionError("This method should not be called.");
         }
 
+        @Override
+        public void deleteGroup(Group target) {
+            throw new AssertionError("This method should not be called.");
+        }
+
         @Override
         public void addGroup(Group group) {
             throw new AssertionError("This method should not be called.");