Re-Implement //regen (#598)

* start reimplementing regen command

* start reimplementing regen command

* Formatting and logic tweaks.

Regen will now throw exceptions but they are not caught yet.
ConversionSessions will now be closed when no longer being used instead of left open.

* fix //regen crashing server

* added //regen support for 1.16.1 and 1.15.2

* cleanup

* Update the issue template

* improve performance of regen by a factor of 40, approx 1.2 millon blocks/second

* Update the issue template

* Update the issue template & add a config (#640)

* Update the issue template

* Add a config.yml to the issue template

* improve performance of regen by a factor of 40, approx 1.2 millon blocks/second

* Fix entity rotation (#642)

* fix entity rotation
fixes #577 
Co-authored-by: wea_ondara <wea_ondara@alpenblock.net>

* Fix toggle permission (#644)

* Fixes #529
* fix superperms perm toggling

Co-authored-by: @weaondara <wea_ondara@alpenblock.net>

* Fix #647

* Squash errors and debug to aid fixing #652 properly

* cleanup imports

* cleanup imports 2

* cleanup imports 3

* cleanup imports 4

* add patch by @SirYwell

* aysnc world gen with features and stuff and some minor issues

* optimizations, full chunkstatus, block populators

* optimizations, cleanup

* optimizations

* fix feature regeneration, fix temp folder deletion

* cleanup

* make chunk gen multithreaded

* fix precomputation of chunk lists for RegionLimitedWorldAccess again

* added regenerator abstraction, fix aioobe while running through chunk stati

* remove override for getChunkAt in freshnmsworld

* don't use concurrent chunk gen if custom chunk generators do not support it

* distinct between generator types

* improve regen speed for overworlds

* mix

* Add message that regen might take a while

* use a shared map for FastAreaLazy, cleanup imports

* use custom concurrency levels for chunk stati and process accordingly

* implement new regen in 1.15.2 and 1.16.1 as well

Conflicts:
	worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/FAWE_Spigot_v1_15_R2.java
	worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/FAWE_Spigot_v1_16_R1.java

* woops

* further abstraction, finalized regen impl

* Formatting

* Fix some typos, remove debug

* replace wildcard imports

* cleanup debug

* braces

* serr -> logger

* move regen impls to seperate classes

* fix world init for 1.16.1

* fix world init for 1.15.2

* fix world init for 1.15.2 #2

* use original world name for regeneration

* Update Regen_v1_15_R2.java

* Update worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/FAWE_Spigot_v1_15_R2.java

Co-authored-by: Matt <4009945+MattBDev@users.noreply.github.com>

* Update worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/FAWE_Spigot_v1_15_R2.java

Co-authored-by: Matt <4009945+MattBDev@users.noreply.github.com>

* Update worldedit-bukkit/src/main/java/com/sk89q/worldedit/bukkit/adapter/impl/FAWE_Spigot_v1_16_R1.java

Co-authored-by: Matt <4009945+MattBDev@users.noreply.github.com>

* improve documentation, use parallel task count for fawe settings

* fix compile

Co-authored-by: wea_ondara <wea_ondara@alpenblock.net>
Co-authored-by: MattBDev <4009945+MattBDev@users.noreply.github.com>
Co-authored-by: dordsor21 <dordsor21@gmail.com>

worldedit-core/src/main/java/com/sk89q/worldedit/command/RegionCommands.java

@@ -616,6 +616,7 @@ public class RegionCommands {
         try {
             session.setMask((Mask) null);
             session.setSourceMask((Mask) null);
+            actor.printInfo(TranslatableComponent.of("fawe.regen.time"));
             success = world.regenerate(region, editSession);
         } finally {
             session.setMask(mask);

worldedit-core/src/main/java/com/sk89q/worldedit/extent/Extent.java

@@ -186,7 +186,7 @@ public interface Extent extends InputExtent, OutputExtent {
     }
 
     default boolean regenerateChunk(int x, int z, @Nullable BiomeType type, @Nullable Long seed) {
-        throw new UnsupportedOperationException("TODO NOT IMPLEMENTED: " + isWorld());
+        return false;
     }
 
     /*

worldedit-core/src/main/java/com/sk89q/worldedit/world/NullWorld.java

@@ -31,6 +31,7 @@ import com.sk89q.worldedit.blocks.BaseItemStack;
 import com.sk89q.worldedit.entity.BaseEntity;
 import com.sk89q.worldedit.entity.Entity;
 import com.sk89q.worldedit.entity.Player;
+import com.sk89q.worldedit.extent.Extent;
 import com.sk89q.worldedit.math.BlockVector3;
 import com.sk89q.worldedit.math.Vector3;
 import com.sk89q.worldedit.regions.Region;
@@ -226,6 +227,10 @@ public class NullWorld extends AbstractWorld {
 
     @Override
     public void sendFakeChunk(@Nullable Player player, ChunkPacket packet) {
+    }
 
+    @Override
+    public boolean regenerate(Region region, Extent extent, RegenOptions options) {
+        return false;
     }
 }

worldedit-core/src/main/java/com/sk89q/worldedit/world/World.java

@@ -31,6 +31,8 @@ import com.sk89q.worldedit.entity.Player;
 import com.sk89q.worldedit.extension.platform.Platform;
 import com.sk89q.worldedit.extent.Extent;
 import com.sk89q.worldedit.function.mask.Mask;
+import com.sk89q.worldedit.internal.util.DeprecationUtil;
+import com.sk89q.worldedit.internal.util.NonAbstractForCompatibility;
 import com.sk89q.worldedit.math.BlockVector2;
 import com.sk89q.worldedit.math.BlockVector3;
 import com.sk89q.worldedit.math.Vector3;
@@ -218,7 +220,44 @@ public interface World extends Extent, Keyed, IChunkCache<IChunkGet> {
      * @param editSession the {@link EditSession}
      * @return true if re-generation was successful
      */
-    boolean regenerate(Region region, EditSession editSession);
+    default boolean regenerate(Region region, EditSession editSession) {
+        return regenerate(region, editSession, RegenOptions.builder().build());
+    }
+
+    /**
+     * Regenerate an area.
+     *
+     * @param region the region
+     * @param extent the {@link Extent}
+     * @return true if re-generation was successful
+     */
+    default boolean regenerate(Region region, Extent extent) {
+        return regenerate(region, extent, RegenOptions.builder().build());
+    }
+
+    /**
+     * Regenerate an area.
+     *
+     * @param region the region
+     * @param extent the {@link Extent}
+     * @param options the regeneration options
+     * @return true if regeneration was successful
+     * @apiNote This must be overridden by new subclasses. See {@link NonAbstractForCompatibility}
+     *          for details
+     */
+    @NonAbstractForCompatibility(
+            delegateName = "regenerate",
+            delegateParams = { Region.class, EditSession.class }
+    )
+    default boolean regenerate(Region region, Extent extent, RegenOptions options) {
+        DeprecationUtil.checkDelegatingOverride(getClass());
+        if (extent instanceof EditSession) {
+            return regenerate(region, (EditSession) extent);
+        }
+        throw new UnsupportedOperationException("This World class ("
+                + getClass().getName()
+                + ") does not implement the general Extent variant of this method");
+    }
 
     /**
      * Generate a tree at the given position.

worldedit-core/src/main/resources/lang/strings.json

@@ -165,6 +165,8 @@
 	"fawe.tips.tip.biome.pattern": "Tip: The #biome[forest] pattern can be used in any command",
 	"fawe.tips.tip.biome.mask": "Tip: Restrict to a biome with the `$jungle` mask",
 
+    "fawe.regen.time": "Regenerating region, this might take a while!",
+
     "worldedit.expand.description.vert": "Vertically expand the selection to world limits.",
     "worldedit.expand.expanded": "Region expanded {0} blocks",
     "worldedit.expand.expanded.vert": "Region expanded {0} blocks (top-to-bottom).",