Add automatic backups and implement them /plot clear and /plot set <component>.

Core/src/main/java/com/plotsquared/core/backup/BackupManager.java

@@ -25,14 +25,30 @@
  */
 package com.plotsquared.core.backup;
 
+import com.plotsquared.core.PlotSquared;
+import com.plotsquared.core.player.PlotPlayer;
 import com.plotsquared.core.plot.Plot;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.nio.file.Path;
-import java.util.concurrent.CompletableFuture;
+import java.util.Objects;
 
 public interface BackupManager {
 
+    /**
+     * This will perform an automatic backup of the plot iff the plot has an owner,
+     * automatic backups are enabled and the plot is not merged.
+     * Otherwise it will complete immediately.
+     *
+     * @param player   Player that triggered the backup
+     * @param plot     Plot to perform the automatic backup on
+     * @param whenDone Action that runs when the automatic backup has been completed
+     */
+    static void backup(@Nullable PlotPlayer player, @NotNull final Plot plot, @NotNull Runnable whenDone) {
+        Objects.requireNonNull(PlotSquared.imp()).getBackupManager().automaticBackup(player, plot, whenDone);
+    }
+
     /**
      * Get the backup profile for a plot based on its
      * current owner (if there is one)
@@ -47,10 +63,11 @@ public interface BackupManager {
      * automatic backups are enabled and the plot is not merged.
      * Otherwise it will complete immediately.
      *
+     * @param player   Player that triggered the backup
      * @param plot     Plot to perform the automatic backup on
-     * @return Future that completes when the backup is finished
+     * @param whenDone Action that runs when the automatic backup has been completed
      */
-    @NotNull CompletableFuture<?> automaticBackup(@NotNull final Plot plot);
+    void automaticBackup(@Nullable PlotPlayer player, @NotNull final Plot plot, @NotNull Runnable whenDone);
 
     /**
      * Get the directory in which backups are stored

Core/src/main/java/com/plotsquared/core/backup/NullBackupManager.java

@@ -26,12 +26,13 @@
 package com.plotsquared.core.backup;
 
 import com.plotsquared.core.PlotSquared;
+import com.plotsquared.core.player.PlotPlayer;
 import com.plotsquared.core.plot.Plot;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.nio.file.Path;
 import java.util.Objects;
-import java.util.concurrent.CompletableFuture;
 
 /**
  * {@inheritDoc}
@@ -42,8 +43,9 @@ public class NullBackupManager implements BackupManager {
         return new NullBackupProfile();
     }
 
-    @Override @NotNull public CompletableFuture<?> automaticBackup(@NotNull Plot plot) {
+    @Override public void automaticBackup(@Nullable PlotPlayer plotPlayer,
-        return CompletableFuture.completedFuture(null);
+        @NotNull Plot plot, @NotNull Runnable whenDone) {
+        whenDone.run();
     }
 
     @Override @NotNull public Path getBackupPath() {

Core/src/main/java/com/plotsquared/core/backup/PlayerBackupProfile.java

@@ -40,6 +40,7 @@ import java.nio.file.Path;
 import java.nio.file.attribute.BasicFileAttributes;
 import java.util.ArrayList;
 import java.util.Collections;
+import java.util.Comparator;
 import java.util.List;
 import java.util.Objects;
 import java.util.UUID;
@@ -95,6 +96,7 @@ public class PlayerBackupProfile implements BackupProfile {
                 } catch (IOException e) {
                     e.printStackTrace();
                 }
+                backups.sort(Comparator.comparingLong(Backup::getCreationTime).reversed());
                 return (this.backupCache = backups);
             });
         }

Core/src/main/java/com/plotsquared/core/backup/SimpleBackupManager.java

@@ -28,17 +28,20 @@ package com.plotsquared.core.backup;
 import com.google.common.cache.Cache;
 import com.google.common.cache.CacheBuilder;
 import com.plotsquared.core.PlotSquared;
+import com.plotsquared.core.configuration.Captions;
 import com.plotsquared.core.configuration.Settings;
+import com.plotsquared.core.player.PlotPlayer;
 import com.plotsquared.core.plot.Plot;
+import com.plotsquared.core.util.task.TaskManager;
 import lombok.AccessLevel;
 import lombok.Getter;
 import lombok.RequiredArgsConstructor;
 import org.jetbrains.annotations.NotNull;
+import org.jetbrains.annotations.Nullable;
 
 import java.nio.file.Files;
 import java.nio.file.Path;
 import java.util.Objects;
-import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutionException;
 import java.util.concurrent.TimeUnit;
 
@@ -75,12 +78,28 @@ import java.util.concurrent.TimeUnit;
         return new NullBackupProfile();
     }
 
-    @Override @NotNull public CompletableFuture<?> automaticBackup(@NotNull final Plot plot) {
+    @Override public void automaticBackup(@Nullable PlotPlayer player, @NotNull final Plot plot, @NotNull Runnable whenDone) {
         final BackupProfile profile;
         if (!this.shouldAutomaticallyBackup() || (profile = getProfile(plot)) instanceof NullBackupProfile) {
-            return CompletableFuture.completedFuture(null);
+            whenDone.run();
+        } else {
+            if (player != null) {
+                Captions.BACKUP_AUTOMATIC_STARTED.send(player);
+            }
+            profile.createBackup().whenComplete((backup, throwable) -> {
+               if (throwable != null) {
+                   if (player != null) {
+                       Captions.BACKUP_AUTOMATIC_FAILURE.send(player, throwable.getMessage());
+                   }
+                   throwable.printStackTrace();
+               } else {
+                   if (player != null) {
+                       Captions.BACKUP_AUTOMATIC_FINISHED.send(player);
+                       TaskManager.runTaskAsync(whenDone);
+                   }
+               }
+            });
         }
-        return profile.createBackup();
     }
 
     @Override public boolean shouldAutomaticallyBackup() {

Core/src/main/java/com/plotsquared/core/command/Clear.java

@@ -26,6 +26,7 @@
 package com.plotsquared.core.command;
 
 import com.plotsquared.core.PlotSquared;
+import com.plotsquared.core.backup.BackupManager;
 import com.plotsquared.core.configuration.Captions;
 import com.plotsquared.core.configuration.Settings;
 import com.plotsquared.core.events.PlotFlagRemoveEvent;
@@ -82,6 +83,7 @@ public class Clear extends Command {
         checkTrue(force || !Settings.Done.RESTRICT_BUILDING || !DoneFlag.isDone(plot) || Permissions
             .hasPermission(player, Captions.PERMISSION_CONTINUE), Captions.DONE_ALREADY_DONE);
         confirm.run(this, () -> {
+            BackupManager.backup(player, plot, () -> {
                 final long start = System.currentTimeMillis();
                 boolean result = plot.clear(true, false, () -> {
                     plot.unlink();
@@ -114,6 +116,7 @@ public class Clear extends Command {
                 } else {
                     plot.addRunning();
                 }
+            });
         }, null);
         return CompletableFuture.completedFuture(true);
     }

Core/src/main/java/com/plotsquared/core/command/Set.java

@@ -25,6 +25,7 @@
  */
 package com.plotsquared.core.command;
 
+import com.plotsquared.core.backup.BackupManager;
 import com.plotsquared.core.configuration.CaptionUtility;
 import com.plotsquared.core.configuration.Captions;
 import com.plotsquared.core.player.PlotPlayer;
@@ -91,12 +92,15 @@ public class Set extends SubCommand {
                             MainUtil.sendMessage(player, Captions.WAIT_FOR_TIMER);
                             return false;
                         }
+
+                        BackupManager.backup(player, plot, () -> {
                             plot.addRunning();
                             for (Plot current : plot.getConnectedPlots()) {
                                 current.setComponent(component, pattern);
                             }
                             MainUtil.sendMessage(player, Captions.GENERATING_COMPONENT);
                             GlobalBlockQueue.IMP.addEmptyTask(plot::removeRunning);
+                        });
                         return true;
                     }
                 }

Core/src/main/java/com/plotsquared/core/configuration/Captions.java

@@ -759,6 +759,9 @@ public enum Captions implements Caption {
     BACKUP_LIST_HEADER("$1Available backups for plot $2%s", "Backups"),
     BACKUP_LIST_ENTRY("$3- $1#%s0 $2%s1", "Backups"),
     BACKUP_LIST_FAILED("$2Backup listing failed: %s", "Backups"),
+    BACKUP_AUTOMATIC_STARTED("$1Backing up the plot...", "Backups"),
+    BACKUP_AUTOMATIC_FINISHED("$1The automatic backup process finished successfully!", "Backups"),
+    BACKUP_AUTOMATIC_FAILURE("$2The automatic backup process failed. Your pending action has been canceled. Reason: %s", "Backups"),
     //</editor-fold>
 
     //<editor-fold desc="Generic">