PipePutEvent now supports additional, custom predicates (#1332)

* PipePutEvent now supports additional, custom predicates

* undid changes to PipePutEvent; introduced PipeFilterEvent

* added filters, exceptions and filteredItems to PipeFilterEvent

* altered indenting of PipeFilterEvent to be conform with other files

* renamed filters to includeFilters and exceptions to excludeFilters

Author: BlvckBytes

src/main/java/com/sk89q/craftbook/mechanics/pipe/PipeFilterEvent.java

@@ -0,0 +1,53 @@
+package com.sk89q.craftbook.mechanics.pipe;
+
+import org.bukkit.block.Block;
+import org.bukkit.event.HandlerList;
+import org.bukkit.inventory.ItemStack;
+
+import javax.annotation.Nonnull;
+import java.util.List;
+import java.util.Set;
+
+public class PipeFilterEvent extends PipeEvent {
+
+    private static final HandlerList handlers = new HandlerList();
+
+    private Set<ItemStack> includeFilters;
+    private Set<ItemStack> excludeFilters;
+    private List<ItemStack> filteredItems;
+
+    public PipeFilterEvent(Block theBlock, List<ItemStack> items, Set<ItemStack> includeFilters, Set<ItemStack> excludeFilters, List<ItemStack> filteredItems) {
+        super(theBlock, items);
+
+        this.includeFilters = includeFilters;
+        this.excludeFilters = excludeFilters;
+        this.filteredItems = filteredItems;
+    }
+
+    public Set<ItemStack> getIncludeFilters() {
+        return includeFilters;
+    }
+
+    public Set<ItemStack> getExcludeFilters() {
+        return excludeFilters;
+    }
+
+    public List<ItemStack> getFilteredItems() {
+        return filteredItems;
+    }
+
+    public void setFilteredItems(List<ItemStack> filteredItems) {
+        this.filteredItems = filteredItems;
+    }
+
+    @Override
+    @Nonnull
+    public HandlerList getHandlers() {
+        return handlers;
+    }
+
+    @Nonnull
+    public static HandlerList getHandlerList() {
+        return handlers;
+    }
+}

src/main/java/com/sk89q/craftbook/mechanics/pipe/Pipes.java

@@ -157,6 +157,11 @@ private void searchNearbyPipes(Block block, Set<Vector> visitedPipes, List<ItemS
 
                 List<ItemStack> filteredItems = new ArrayList<>(VerifyUtil.withoutNulls(ItemUtil.filterItems(items, pFilters, pExceptions)));
 
+                PipeFilterEvent filterEvent = new PipeFilterEvent(bl, items, pFilters, pExceptions, filteredItems);
+                Bukkit.getPluginManager().callEvent(filterEvent);
+
+                filteredItems = filterEvent.getFilteredItems();
+
                 if(filteredItems.isEmpty())
                     continue;