Implement habit deletion

app/src/main/java/org/isoron/uhabits/commands/DeleteHabitsCommand.java

@@ -0,0 +1,56 @@
+/* Copyright (C) 2016 Alinson Santos Xavier
+ *
+ * This program is free software: you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation, either version 3 of the License, or (at your option)
+ * any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied  warranty of MERCHANTABILITY or
+ * FITNESS  FOR  A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You  should  have  received  a  copy  of the GNU General Public License
+ * along  with  this  program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package org.isoron.uhabits.commands;
+
+import org.isoron.helpers.Command;
+import org.isoron.uhabits.R;
+import org.isoron.uhabits.models.Habit;
+
+import java.util.List;
+
+public class DeleteHabitsCommand extends Command
+{
+    private List<Habit> habits;
+
+    public DeleteHabitsCommand(List<Habit> habits)
+    {
+        this.habits = habits;
+    }
+
+    @Override
+    public void execute()
+    {
+        for(Habit h : habits)
+            h.cascadeDelete();
+    }
+
+    @Override
+    public void undo()
+    {
+
+    }
+
+    public Integer getExecuteStringId()
+    {
+        return R.string.toast_habit_deleted;
+    }
+
+    public Integer getUndoStringId()
+    {
+        return R.string.toast_habit_restored;
+    }
+}

app/src/main/java/org/isoron/uhabits/fragments/ListHabitsFragment.java

@@ -19,16 +19,16 @@ package org.isoron.uhabits.fragments;
 import android.animation.Animator;
 import android.animation.AnimatorListenerAdapter;
 import android.app.Activity;
+import android.app.AlertDialog;
 import android.app.Fragment;
 import android.content.Context;
+import android.content.DialogInterface;
 import android.content.SharedPreferences;
 import android.graphics.Color;
-import android.graphics.Point;
 import android.graphics.Typeface;
 import android.os.Bundle;
 import android.preference.PreferenceManager;
 import android.util.DisplayMetrics;
-import android.util.Log;
 import android.view.ActionMode;
 import android.view.ContextMenu;
 import android.view.ContextMenu.ContextMenuInfo;
@@ -65,6 +65,7 @@ import org.isoron.helpers.ReplayableActivity;
 import org.isoron.uhabits.R;
 import org.isoron.uhabits.commands.ArchiveHabitsCommand;
 import org.isoron.uhabits.commands.ChangeHabitColorCommand;
+import org.isoron.uhabits.commands.DeleteHabitsCommand;
 import org.isoron.uhabits.commands.UnarchiveHabitsCommand;
 import org.isoron.uhabits.helpers.ReminderHelper;
 import org.isoron.uhabits.loaders.HabitListLoader;
@@ -178,6 +179,23 @@ public class ListHabitsFragment extends Fragment
                     });
                     picker.show(getFragmentManager(), "picker");
                 }
+
+                case R.id.action_delete:
+                {
+                    new AlertDialog.Builder(activity)
+                            .setTitle(R.string.delete_habits)
+                            .setMessage(R.string.delete_habits_message)
+                            .setPositiveButton(android.R.string.yes, new DialogInterface.OnClickListener()
+                            {
+                                @Override
+                                public void onClick(DialogInterface dialog, int which)
+                                {
+                                    executeCommand(new DeleteHabitsCommand(selectedHabits), null);
+                                    mode.finish();
+                                }
+                            }).setNegativeButton(android.R.string.no, null)
+                            .show();
+                }
             }
 
             return false;

app/src/main/java/org/isoron/uhabits/models/Habit.java

@@ -215,6 +215,27 @@ public class Habit extends Model
         return (count > 0);
     }
 
+    public void cascadeDelete()
+    {
+        Long id = getId();
+
+        ActiveAndroid.beginTransaction();
+        try
+        {
+            new Delete().from(Checkmark.class).where("habit = ?", id).execute();
+            new Delete().from(Repetition.class).where("habit = ?", id).execute();
+            new Delete().from(Score.class).where("habit = ?", id).execute();
+            new Delete().from(Streak.class).where("habit = ?", id).execute();
+            delete();
+
+            ActiveAndroid.setTransactionSuccessful();
+        }
+        finally
+        {
+            ActiveAndroid.endTransaction();
+        }
+    }
+
     public void deleteReps(long timestamp)
     {
         new Delete().from(Repetition.class)