Expose an interface for custom metals chest condensation rules

src/main/java/mods/railcraft/api/items/IMetalsChestCondenseRule.java

@@ -0,0 +1,53 @@
+/*------------------------------------------------------------------------------
+ Copyright (c) CovertJaguar, 2011-2019
+
+ This work (the API) is licensed under the "MIT" License,
+ see LICENSE.md for details.
+ -----------------------------------------------------------------------------*/
+
+package mods.railcraft.api.items;
+
+import net.minecraft.item.ItemStack;
+
+import java.util.ArrayList;
+import java.util.List;
+import java.util.function.Predicate;
+
+/**
+ * A condensation rule for metal chests.
+ */
+public interface IMetalsChestCondenseRule {
+    /**
+     * A list of metals chest condense rules the metals chest will check.
+     */
+    List<IMetalsChestCondenseRule> rules = new ArrayList<>();
+
+    /**
+     * Checks if an item can be consumed for condensation
+     *
+     * @return the predicate to check if an item matches
+     */
+    Predicate<ItemStack> getPredicate();
+
+    /**
+     * Returns the number of item needed for one condensation.
+     */
+    int removeCount();
+
+    /**
+     * Gets the condensation result. Make sure to make clean copies!
+     */
+    ItemStack getResult();
+
+    /**
+     * Utility method for quickly creating a metals chest condensation rule.
+     *
+     * @param predicate the checker
+     * @param count the requirement count
+     * @param result the compressed result
+     * @return the created rule
+     */
+    static IMetalsChestCondenseRule of(Predicate<ItemStack> predicate, int count, ItemStack result) {
+        return new MetalsChestCondenseRuleImpl(predicate, count, result);
+    }
+}

src/main/java/mods/railcraft/api/items/MetalsChestCondenseRuleImpl.java

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+/*------------------------------------------------------------------------------
+ Copyright (c) CovertJaguar, 2011-2019
+
+ This work (the API) is licensed under the "MIT" License,
+ see LICENSE.md for details.
+ -----------------------------------------------------------------------------*/
+
+package mods.railcraft.api.items;
+
+import net.minecraft.item.ItemStack;
+
+import java.util.function.Predicate;
+
+class MetalsChestCondenseRuleImpl implements IMetalsChestCondenseRule {
+    private final Predicate<ItemStack> predicate;
+    private final int count;
+    private final ItemStack output;
+
+    MetalsChestCondenseRuleImpl(Predicate<ItemStack> predicate, int count, ItemStack output) {
+        this.predicate = predicate;
+        this.count = count;
+        this.output = output.copy();
+    }
+
+    @Override
+    public Predicate<ItemStack> getPredicate() {
+        return predicate;
+    }
+
+    @Override
+    public int removeCount() {
+        return count;
+    }
+
+    @Override
+    public ItemStack getResult() {
+        return output.copy();
+    }
+}