Refactor out our JEI plugin into reusable components

Pretty useless right now, but either useful for CC:R or our eventual
multi-loader support.

src/main/java/dan200/computercraft/shared/integration/RecipeModHelpers.java

@@ -0,0 +1,70 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2022. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+package dan200.computercraft.shared.integration;
+
+import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.shared.PocketUpgrades;
+import dan200.computercraft.shared.TurtleUpgrades;
+import dan200.computercraft.shared.computer.core.ComputerFamily;
+import dan200.computercraft.shared.pocket.items.PocketComputerItemFactory;
+import dan200.computercraft.shared.turtle.items.TurtleItemFactory;
+import net.minecraft.item.ItemStack;
+import net.minecraft.util.ResourceLocation;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * Utilities for recipe mod plugins (such as JEI).
+ */
+public final class RecipeModHelpers
+{
+    static final List<ComputerFamily> MAIN_FAMILIES = Arrays.asList( ComputerFamily.NORMAL, ComputerFamily.ADVANCED );
+
+    private RecipeModHelpers()
+    {
+    }
+
+    /**
+     * Determine if a recipe should be hidden. This should be used in conjunction with {@link UpgradeRecipeGenerator}
+     * to hide our upgrade crafting recipes.
+     *
+     * @param id The recipe ID.
+     * @return Whether it should be removed.
+     */
+    public static boolean shouldRemoveRecipe( ResourceLocation id )
+    {
+        if( !id.getNamespace().equals( ComputerCraft.MOD_ID ) ) return false;
+
+        String path = id.getPath();
+        return path.startsWith( "turtle_normal/" ) || path.startsWith( "turtle_advanced/" )
+            || path.startsWith( "pocket_normal/" ) || path.startsWith( "pocket_advanced/" );
+    }
+
+    /**
+     * Get additional ComputerCraft-related items which may not be visible in a creative tab. This includes upgraded
+     * turtle and pocket computers for each upgrade.
+     *
+     * @return The additional stacks to show.
+     */
+    public static List<ItemStack> getExtraStacks()
+    {
+        List<ItemStack> upgradeItems = new ArrayList<>();
+        for( ComputerFamily family : MAIN_FAMILIES )
+        {
+            TurtleUpgrades.getUpgrades().forEach( upgrade -> {
+                upgradeItems.add( TurtleItemFactory.create( -1, null, -1, family, null, upgrade, 0, null ) );
+            } );
+
+            PocketUpgrades.getUpgrades().forEach( upgrade -> {
+                upgradeItems.add( PocketComputerItemFactory.create( -1, null, -1, family, upgrade ) );
+            } );
+        }
+
+        return upgradeItems;
+    }
+}

src/main/java/dan200/computercraft/shared/integration/UpgradeRecipeGenerator.java

@@ -0,0 +1,338 @@
+/*
+ * This file is part of ComputerCraft - http://www.computercraft.info
+ * Copyright Daniel Ratcliffe, 2011-2022. Do not distribute without permission.
+ * Send enquiries to dratcliffe@gmail.com
+ */
+package dan200.computercraft.shared.integration;
+
+import dan200.computercraft.ComputerCraft;
+import dan200.computercraft.api.IUpgradeBase;
+import dan200.computercraft.api.pocket.IPocketUpgrade;
+import dan200.computercraft.api.turtle.ITurtleUpgrade;
+import dan200.computercraft.api.turtle.TurtleSide;
+import dan200.computercraft.shared.PocketUpgrades;
+import dan200.computercraft.shared.TurtleUpgrades;
+import dan200.computercraft.shared.computer.core.ComputerFamily;
+import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
+import dan200.computercraft.shared.pocket.items.PocketComputerItemFactory;
+import dan200.computercraft.shared.turtle.items.ItemTurtle;
+import dan200.computercraft.shared.turtle.items.TurtleItemFactory;
+import net.minecraft.item.Item;
+import net.minecraft.item.ItemStack;
+import net.minecraft.item.crafting.ICraftingRecipe;
+import net.minecraft.item.crafting.Ingredient;
+import net.minecraft.item.crafting.ShapedRecipe;
+import net.minecraft.util.NonNullList;
+import net.minecraft.util.ResourceLocation;
+
+import javax.annotation.Nullable;
+import java.util.*;
+import java.util.function.Function;
+
+import static dan200.computercraft.shared.integration.RecipeModHelpers.MAIN_FAMILIES;
+
+/**
+ * Provides dynamic recipe and usage information for upgraded turtle and pocket computers. This is intended to be
+ * consumed by our recipe mod plugins (for example JEI).
+ *
+ * @param <T> The type the recipe mod uses for recipes.
+ * @see RecipeModHelpers
+ */
+public class UpgradeRecipeGenerator<T>
+{
+    private static final ResourceLocation TURTLE_UPGRADE = new ResourceLocation( ComputerCraft.MOD_ID, "turtle_upgrade" );
+    private static final ResourceLocation POCKET_UPGRADE = new ResourceLocation( ComputerCraft.MOD_ID, "pocket_upgrade" );
+
+    private final Function<ICraftingRecipe, T> wrap;
+
+    private final Map<Item, List<UpgradeInfo>> upgradeItemLookup = new HashMap<>();
+    private final List<UpgradeInfo> pocketUpgrades = new ArrayList<>();
+    private final List<UpgradeInfo> turtleUpgrades = new ArrayList<>();
+    private boolean initialised = false;
+
+    public UpgradeRecipeGenerator( Function<ICraftingRecipe, T> wrap )
+    {
+        this.wrap = wrap;
+    }
+
+    /**
+     * Build a cache of items which are used for turtle and pocket computer upgrades.
+     */
+    private void setupCache()
+    {
+        if( initialised ) return;
+        initialised = true;
+
+        TurtleUpgrades.getUpgrades().forEach( upgrade -> {
+            net.minecraft.item.ItemStack stack = upgrade.getCraftingItem();
+            if( stack.isEmpty() ) return;
+
+            UpgradeInfo info = new UpgradeInfo( stack, upgrade );
+            upgradeItemLookup.computeIfAbsent( stack.getItem(), k -> new ArrayList<>( 1 ) ).add( info );
+            turtleUpgrades.add( info );
+        } );
+
+        PocketUpgrades.getUpgrades().forEach( upgrade -> {
+            ItemStack stack = upgrade.getCraftingItem();
+            if( stack.isEmpty() ) return;
+
+            UpgradeInfo info = new UpgradeInfo( stack, upgrade );
+            upgradeItemLookup.computeIfAbsent( stack.getItem(), k -> new ArrayList<>( 1 ) ).add( info );
+            pocketUpgrades.add( info );
+        } );
+    }
+
+    /**
+     * Check if this item is usable as a turtle or pocket computer upgrade.
+     *
+     * @param stack The stack to check.
+     * @return Whether the item is an upgrade.
+     */
+    public boolean isUpgrade( ItemStack stack )
+    {
+        if( stack.isEmpty() ) return false;
+
+        setupCache();
+        List<UpgradeInfo> upgrades = upgradeItemLookup.get( stack.getItem() );
+        if( upgrades == null ) return false;
+
+        for( UpgradeInfo upgrade : upgrades )
+        {
+            ItemStack craftingStack = upgrade.stack;
+            if( !craftingStack.isEmpty() && craftingStack.getItem() == stack.getItem() && upgrade.upgrade.isItemSuitable( stack ) )
+            {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+    /**
+     * Find all usages of the given stack.
+     *
+     * @param stack The stack to find usages of.
+     * @return All upgrade recipes which take the current stack as an input.
+     */
+    public List<T> findRecipesWithInput( ItemStack stack )
+    {
+        setupCache();
+
+        if( stack.getItem() instanceof ItemTurtle )
+        {
+            ItemTurtle item = (ItemTurtle) stack.getItem();
+
+            // Suggest possible upgrades which can be applied to this turtle
+            ITurtleUpgrade left = item.getUpgrade( stack, TurtleSide.LEFT );
+            ITurtleUpgrade right = item.getUpgrade( stack, TurtleSide.RIGHT );
+            if( left != null && right != null ) return Collections.emptyList();
+
+            List<T> recipes = new ArrayList<>();
+            Ingredient ingredient = Ingredient.of( stack );
+            for( UpgradeInfo upgrade : turtleUpgrades )
+            {
+                // The turtle is facing towards us, so upgrades on the left are actually crafted on the right.
+                if( left == null )
+                {
+                    recipes.add( turtle( ingredient, upgrade.ingredient, turtleWith( stack, upgrade.turtle, right ) ) );
+                }
+
+                if( right == null )
+                {
+                    recipes.add( turtle( upgrade.ingredient, ingredient, turtleWith( stack, left, upgrade.turtle ) ) );
+                }
+            }
+
+            return Collections.unmodifiableList( recipes );
+        }
+        else if( stack.getItem() instanceof ItemPocketComputer )
+        {
+            // Suggest possible upgrades which can be applied to this turtle
+            IPocketUpgrade back = ItemPocketComputer.getUpgrade( stack );
+            if( back != null ) return Collections.emptyList();
+
+            List<T> recipes = new ArrayList<>();
+            Ingredient ingredient = Ingredient.of( stack );
+            for( UpgradeInfo upgrade : pocketUpgrades )
+            {
+                recipes.add( pocket( upgrade.ingredient, ingredient, pocketWith( stack, upgrade.pocket ) ) );
+            }
+
+            return Collections.unmodifiableList( recipes );
+        }
+        else
+        {
+            // If this item is usable as an upgrade, find all possible recipes.
+            List<UpgradeInfo> upgrades = upgradeItemLookup.get( stack.getItem() );
+            if( upgrades == null ) return Collections.emptyList();
+
+            List<T> recipes = null;
+            boolean multiple = false;
+            for( UpgradeInfo upgrade : upgrades )
+            {
+                ItemStack craftingStack = upgrade.stack;
+                if( craftingStack.isEmpty() || craftingStack.getItem() != stack.getItem() || !upgrade.upgrade.isItemSuitable( stack ) )
+                {
+                    continue;
+                }
+
+                if( recipes == null )
+                {
+                    recipes = upgrade.getRecipes();
+                }
+                else
+                {
+                    if( !multiple )
+                    {
+                        multiple = true;
+                        recipes = new ArrayList<>( recipes );
+                    }
+                    recipes.addAll( upgrade.getRecipes() );
+                }
+            }
+
+            return recipes == null ? Collections.emptyList() : Collections.unmodifiableList( recipes );
+        }
+    }
+
+    /**
+     * Find all recipes for the given stack.
+     *
+     * @param stack The stack to find recipes of.
+     * @return All upgrade recipes which produce the stack as an output.
+     */
+    public List<T> findRecipesWithOutput( ItemStack stack )
+    {
+        // Find which upgrade this item currently has, and so how we could build it.
+        if( stack.getItem() instanceof ItemTurtle )
+        {
+            ItemTurtle item = (ItemTurtle) stack.getItem();
+            List<T> recipes = new ArrayList<>( 0 );
+
+            ITurtleUpgrade left = item.getUpgrade( stack, TurtleSide.LEFT );
+            ITurtleUpgrade right = item.getUpgrade( stack, TurtleSide.RIGHT );
+
+            // The turtle is facing towards us, so upgrades on the left are actually crafted on the right.
+            if( left != null )
+            {
+                recipes.add( turtle(
+                    Ingredient.of( turtleWith( stack, null, right ) ),
+                    Ingredient.of( left.getCraftingItem() ),
+                    stack
+                ) );
+            }
+
+            if( right != null )
+            {
+                recipes.add( turtle(
+                    Ingredient.of( right.getCraftingItem() ),
+                    Ingredient.of( turtleWith( stack, left, null ) ),
+                    stack
+                ) );
+            }
+
+            return Collections.unmodifiableList( recipes );
+        }
+        else if( stack.getItem() instanceof ItemPocketComputer )
+        {
+            List<T> recipes = new ArrayList<>( 0 );
+
+            IPocketUpgrade back = ItemPocketComputer.getUpgrade( stack );
+            if( back != null )
+            {
+                recipes.add( pocket( Ingredient.of( back.getCraftingItem() ), Ingredient.of( pocketWith( stack, null ) ), stack ) );
+            }
+
+            return Collections.unmodifiableList( recipes );
+        }
+        else
+        {
+            return Collections.emptyList();
+        }
+    }
+
+    private static ItemStack turtleWith( ItemStack stack, @Nullable ITurtleUpgrade left, @Nullable ITurtleUpgrade right )
+    {
+        ItemTurtle item = (ItemTurtle) stack.getItem();
+        return TurtleItemFactory.create(
+            item.getComputerID( stack ), item.getLabel( stack ), item.getColour( stack ), item.getFamily(),
+            left, right, item.getFuelLevel( stack ), item.getOverlay( stack )
+        );
+    }
+
+    private static ItemStack pocketWith( ItemStack stack, @Nullable IPocketUpgrade back )
+    {
+        ItemPocketComputer item = (ItemPocketComputer) stack.getItem();
+        return PocketComputerItemFactory.create(
+            item.getComputerID( stack ), item.getLabel( stack ), item.getColour( stack ), item.getFamily(),
+            back
+        );
+    }
+
+    private T pocket( Ingredient upgrade, Ingredient pocketComputer, ItemStack result )
+    {
+        return wrap.apply( new ShapedRecipe( POCKET_UPGRADE, "", 1, 2, NonNullList.of( Ingredient.EMPTY, upgrade, pocketComputer ), result ) );
+    }
+
+    private T turtle( Ingredient left, Ingredient right, ItemStack result )
+    {
+        return wrap.apply( new ShapedRecipe( TURTLE_UPGRADE, "", 2, 1, NonNullList.of( Ingredient.EMPTY, left, right ), result ) );
+    }
+
+    private class UpgradeInfo
+    {
+        final ItemStack stack;
+        final Ingredient ingredient;
+        final @Nullable ITurtleUpgrade turtle;
+        final @Nullable IPocketUpgrade pocket;
+        final IUpgradeBase upgrade;
+        private @Nullable ArrayList<T> recipes;
+
+        UpgradeInfo( ItemStack stack, ITurtleUpgrade turtle )
+        {
+            this.stack = stack;
+            ingredient = Ingredient.of( stack );
+            upgrade = this.turtle = turtle;
+            pocket = null;
+        }
+
+        UpgradeInfo( ItemStack stack, IPocketUpgrade pocket )
+        {
+            this.stack = stack;
+            ingredient = Ingredient.of( stack );
+            turtle = null;
+            upgrade = this.pocket = pocket;
+        }
+
+        List<T> getRecipes()
+        {
+            ArrayList<T> recipes = this.recipes;
+            if( recipes != null ) return recipes;
+
+            recipes = this.recipes = new ArrayList<>( 4 );
+            for( ComputerFamily family : MAIN_FAMILIES )
+            {
+                if( turtle != null )
+                {
+                    recipes.add( turtle(
+                        ingredient, // Right upgrade, recipe on left
+                        Ingredient.of( TurtleItemFactory.create( -1, null, -1, family, null, null, 0, null ) ),
+                        TurtleItemFactory.create( -1, null, -1, family, null, turtle, 0, null )
+                    ) );
+                }
+
+                if( pocket != null )
+                {
+                    recipes.add( pocket(
+                        ingredient,
+                        Ingredient.of( PocketComputerItemFactory.create( -1, null, -1, family, null ) ),
+                        PocketComputerItemFactory.create( -1, null, -1, family, pocket )
+                    ) );
+                }
+            }
+
+            recipes.trimToSize();
+            return recipes;
+        }
+    }
+}

src/main/java/dan200/computercraft/shared/integration/jei/JEIComputerCraft.java

@@ -9,15 +9,11 @@ import dan200.computercraft.ComputerCraft;
 import dan200.computercraft.api.pocket.IPocketUpgrade;
 import dan200.computercraft.api.turtle.ITurtleUpgrade;
 import dan200.computercraft.api.turtle.TurtleSide;
-import dan200.computercraft.shared.PocketUpgrades;
 import dan200.computercraft.shared.Registry;
-import dan200.computercraft.shared.TurtleUpgrades;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
+import dan200.computercraft.shared.integration.RecipeModHelpers;
 import dan200.computercraft.shared.media.items.ItemDisk;
 import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
-import dan200.computercraft.shared.pocket.items.PocketComputerItemFactory;
 import dan200.computercraft.shared.turtle.items.ITurtleItem;
-import dan200.computercraft.shared.turtle.items.TurtleItemFactory;
 import mezz.jei.api.IModPlugin;
 import mezz.jei.api.JeiPlugin;
 import mezz.jei.api.constants.VanillaRecipeCategoryUid;
@@ -34,11 +30,8 @@ import net.minecraft.item.crafting.IRecipe;
 import net.minecraft.util.ResourceLocation;
 
 import javax.annotation.Nonnull;
-import java.util.ArrayList;
 import java.util.List;
 
-import static dan200.computercraft.shared.integration.jei.RecipeResolver.MAIN_FAMILIES;
-
 @JeiPlugin
 public class JEIComputerCraft implements IModPlugin
 {
@@ -73,21 +66,11 @@ public class JEIComputerCraft implements IModPlugin
         IRecipeManager registry = runtime.getRecipeManager();
 
         // Register all turtles/pocket computers (not just vanilla upgrades) as upgrades on JEI.
-        List<ItemStack> upgradeItems = new ArrayList<>();
-        for( ComputerFamily family : MAIN_FAMILIES )
+        List<ItemStack> upgradeItems = RecipeModHelpers.getExtraStacks();
+        if( !upgradeItems.isEmpty() )
         {
-            TurtleUpgrades.getUpgrades()
-                .filter( x -> TurtleUpgrades.suitableForFamily( family, x ) )
-                .map( x -> TurtleItemFactory.create( -1, null, -1, family, null, x, 0, null ) )
-                .forEach( upgradeItems::add );
-
-            for( IPocketUpgrade upgrade : PocketUpgrades.getUpgrades() )
-            {
-                upgradeItems.add( PocketComputerItemFactory.create( -1, null, -1, family, upgrade ) );
-            }
-        }
-
             runtime.getIngredientManager().addIngredientsAtRuntime( VanillaTypes.ITEM, upgradeItems );
+        }
 
         // Hide all upgrade recipes
         IRecipeCategory<?> category = registry.getRecipeCategory( VanillaRecipeCategoryUid.CRAFTING );
@@ -96,12 +79,7 @@ public class JEIComputerCraft implements IModPlugin
             for( Object wrapper : registry.getRecipes( category ) )
             {
                 if( !(wrapper instanceof IRecipe) ) continue;
-                ResourceLocation id = ((IRecipe<?>) wrapper).getId();
-                if( !id.getNamespace().equals( ComputerCraft.MOD_ID ) ) continue;
-
-                String path = id.getPath();
-                if( path.startsWith( "turtle_normal/" ) || path.startsWith( "turtle_advanced/" )
-                    || path.startsWith( "pocket_normal/" ) || path.startsWith( "pocket_advanced/" ) )
+                if( RecipeModHelpers.shouldRemoveRecipe( ((IRecipe<?>) wrapper).getId() ) )
                 {
                     registry.hideRecipe( wrapper, VanillaRecipeCategoryUid.CRAFTING );
                 }

src/main/java/dan200/computercraft/shared/integration/jei/RecipeResolver.java

@@ -5,110 +5,41 @@
  */
 package dan200.computercraft.shared.integration.jei;
 
-import dan200.computercraft.ComputerCraft;
-import dan200.computercraft.api.IUpgradeBase;
-import dan200.computercraft.api.pocket.IPocketUpgrade;
-import dan200.computercraft.api.turtle.ITurtleUpgrade;
-import dan200.computercraft.api.turtle.TurtleSide;
-import dan200.computercraft.shared.PocketUpgrades;
-import dan200.computercraft.shared.TurtleUpgrades;
-import dan200.computercraft.shared.computer.core.ComputerFamily;
+import dan200.computercraft.shared.integration.UpgradeRecipeGenerator;
 import dan200.computercraft.shared.pocket.items.ItemPocketComputer;
-import dan200.computercraft.shared.pocket.items.PocketComputerItemFactory;
-import dan200.computercraft.shared.turtle.items.ITurtleItem;
-import dan200.computercraft.shared.turtle.items.TurtleItemFactory;
+import dan200.computercraft.shared.turtle.items.ItemTurtle;
 import mezz.jei.api.constants.VanillaRecipeCategoryUid;
 import mezz.jei.api.recipe.IFocus;
 import mezz.jei.api.recipe.advanced.IRecipeManagerPlugin;
 import mezz.jei.api.recipe.category.IRecipeCategory;
-import net.minecraft.item.Item;
 import net.minecraft.item.ItemStack;
-import net.minecraft.item.crafting.IRecipeSerializer;
-import net.minecraft.item.crafting.Ingredient;
-import net.minecraft.item.crafting.ShapedRecipe;
-import net.minecraft.util.NonNullList;
+import net.minecraft.item.crafting.ICraftingRecipe;
 import net.minecraft.util.ResourceLocation;
 
 import javax.annotation.Nonnull;
-import java.util.*;
-
-import static net.minecraft.item.crafting.Ingredient.of;
-import static net.minecraft.util.NonNullList.of;
+import java.util.Collections;
+import java.util.List;
 
 class RecipeResolver implements IRecipeManagerPlugin
 {
-    static final ComputerFamily[] MAIN_FAMILIES = new ComputerFamily[] { ComputerFamily.NORMAL, ComputerFamily.ADVANCED };
-
-    private final Map<Item, List<UpgradeInfo>> upgradeItemLookup = new HashMap<>();
-    private final List<UpgradeInfo> pocketUpgrades = new ArrayList<>();
-    private final List<UpgradeInfo> turtleUpgrades = new ArrayList<>();
-    private boolean initialised = false;
-
-    /**
-     * Build a cache of items which are used for turtle and pocket computer upgrades.
-     */
-    private void setupCache()
-    {
-        if( initialised ) return;
-        initialised = true;
-
-        TurtleUpgrades.getUpgrades().forEach( upgrade -> {
-            ItemStack stack = upgrade.getCraftingItem();
-            if( stack.isEmpty() ) return;
-
-            UpgradeInfo info = new UpgradeInfo( stack, upgrade );
-            upgradeItemLookup.computeIfAbsent( stack.getItem(), k -> new ArrayList<>( 1 ) ).add( info );
-            turtleUpgrades.add( info );
-        } );
-
-        for( IPocketUpgrade upgrade : PocketUpgrades.getUpgrades() )
-        {
-            ItemStack stack = upgrade.getCraftingItem();
-            if( stack.isEmpty() ) continue;
-
-            UpgradeInfo info = new UpgradeInfo( stack, upgrade );
-            upgradeItemLookup.computeIfAbsent( stack.getItem(), k -> new ArrayList<>( 1 ) ).add( info );
-            pocketUpgrades.add( info );
-        }
-    }
-
-    private boolean hasUpgrade( @Nonnull ItemStack stack )
-    {
-        if( stack.isEmpty() ) return false;
-
-        setupCache();
-        List<UpgradeInfo> upgrades = upgradeItemLookup.get( stack.getItem() );
-        if( upgrades == null ) return false;
-
-        for( UpgradeInfo upgrade : upgrades )
-        {
-            ItemStack craftingStack = upgrade.stack;
-            if( !craftingStack.isEmpty() && craftingStack.getItem() == stack.getItem() && upgrade.upgrade.isItemSuitable( stack ) )
-            {
-                return true;
-            }
-        }
-
-        return false;
-    }
+    private final UpgradeRecipeGenerator<ICraftingRecipe> resolver = new UpgradeRecipeGenerator<>( x -> x );
 
     @Nonnull
     @Override
-    public <V> List<ResourceLocation> getRecipeCategoryUids( @Nonnull IFocus<V> focus )
+    public <V> List<ResourceLocation> getRecipeCategoryUids( IFocus<V> focus )
     {
-        V value = focus.getValue();
+        Object value = focus.getValue();
         if( !(value instanceof ItemStack) ) return Collections.emptyList();
 
         ItemStack stack = (ItemStack) value;
         switch( focus.getMode() )
         {
             case INPUT:
-                return stack.getItem() instanceof ITurtleItem || stack.getItem() instanceof ItemPocketComputer ||
-                    hasUpgrade( stack )
+                return stack.getItem() instanceof ItemTurtle || stack.getItem() instanceof ItemPocketComputer || resolver.isUpgrade( stack )
                     ? Collections.singletonList( VanillaRecipeCategoryUid.CRAFTING )
                     : Collections.emptyList();
             case OUTPUT:
-                return stack.getItem() instanceof ITurtleItem || stack.getItem() instanceof ItemPocketComputer
+                return stack.getItem() instanceof ItemTurtle || stack.getItem() instanceof ItemPocketComputer
                     ? Collections.singletonList( VanillaRecipeCategoryUid.CRAFTING )
                     : Collections.emptyList();
             default:
@@ -118,20 +49,19 @@ class RecipeResolver implements IRecipeManagerPlugin
 
     @Nonnull
     @Override
-    public <T, V> List<T> getRecipes( @Nonnull IRecipeCategory<T> recipeCategory, @Nonnull IFocus<V> focus )
+    public <T, V> List<T> getRecipes( @Nonnull IRecipeCategory<T> recipeCategory, IFocus<V> focus )
     {
         if( !(focus.getValue() instanceof ItemStack) || !recipeCategory.getUid().equals( VanillaRecipeCategoryUid.CRAFTING ) )
         {
             return Collections.emptyList();
         }
 
-        ItemStack stack = (ItemStack) focus.getValue();
         switch( focus.getMode() )
         {
             case INPUT:
-                return cast( findRecipesWithInput( stack ) );
+                return cast( resolver.findRecipesWithInput( (ItemStack) focus.getValue() ) );
             case OUTPUT:
-                return cast( findRecipesWithOutput( stack ) );
+                return cast( resolver.findRecipesWithOutput( (ItemStack) focus.getValue() ) );
             default:
                 return Collections.emptyList();
         }
@@ -144,241 +74,10 @@ class RecipeResolver implements IRecipeManagerPlugin
         return Collections.emptyList();
     }
 
-    @Nonnull
-    private List<Shaped> findRecipesWithInput( @Nonnull ItemStack stack )
-    {
-        setupCache();
-
-        if( stack.getItem() instanceof ITurtleItem )
-        {
-            // Suggest possible upgrades which can be applied to this turtle
-            ITurtleItem item = (ITurtleItem) stack.getItem();
-            ITurtleUpgrade left = item.getUpgrade( stack, TurtleSide.LEFT );
-            ITurtleUpgrade right = item.getUpgrade( stack, TurtleSide.RIGHT );
-            if( left != null && right != null ) return Collections.emptyList();
-
-            List<Shaped> recipes = new ArrayList<>();
-            Ingredient ingredient = of( stack );
-            for( UpgradeInfo upgrade : turtleUpgrades )
-            {
-                // The turtle is facing towards us, so upgrades on the left are actually crafted on the right.
-                if( left == null )
-                {
-                    recipes.add( horizontal( of( Ingredient.EMPTY, ingredient, upgrade.ingredient ), turtleWith( stack, upgrade.turtle, right ) ) );
-                }
-
-                if( right == null )
-                {
-                    recipes.add( horizontal( of( Ingredient.EMPTY, upgrade.ingredient, ingredient ), turtleWith( stack, left, upgrade.turtle ) ) );
-                }
-            }
-
-            return cast( recipes );
-        }
-        else if( stack.getItem() instanceof ItemPocketComputer )
-        {
-            // Suggest possible upgrades which can be applied to this turtle
-            IPocketUpgrade back = ItemPocketComputer.getUpgrade( stack );
-            if( back != null ) return Collections.emptyList();
-
-            List<Shaped> recipes = new ArrayList<>();
-            Ingredient ingredient = of( stack );
-            for( UpgradeInfo upgrade : pocketUpgrades )
-            {
-                recipes.add( vertical( of( Ingredient.EMPTY, ingredient, upgrade.ingredient ), pocketWith( stack, upgrade.pocket ) ) );
-            }
-
-            return recipes;
-        }
-        else
-        {
-            List<UpgradeInfo> upgrades = upgradeItemLookup.get( stack.getItem() );
-            if( upgrades == null ) return Collections.emptyList();
-
-            List<Shaped> recipes = null;
-            boolean multiple = false;
-            for( UpgradeInfo upgrade : upgrades )
-            {
-                ItemStack craftingStack = upgrade.stack;
-                if( craftingStack.isEmpty() || craftingStack.getItem() != stack.getItem() || !upgrade.upgrade.isItemSuitable( stack ) )
-                {
-                    continue;
-                }
-
-                if( recipes == null )
-                {
-                    recipes = upgrade.getRecipes();
-                }
-                else
-                {
-                    if( !multiple )
-                    {
-                        multiple = true;
-                        recipes = new ArrayList<>( recipes );
-                    }
-                    recipes.addAll( upgrade.getRecipes() );
-                }
-            }
-
-            return recipes == null ? Collections.emptyList() : recipes;
-        }
-    }
-
-    @Nonnull
-    private static List<Shaped> findRecipesWithOutput( @Nonnull ItemStack stack )
-    {
-        // Find which upgrade this item currently has, an so how we could build it.
-        if( stack.getItem() instanceof ITurtleItem )
-        {
-            ITurtleItem item = (ITurtleItem) stack.getItem();
-            List<Shaped> recipes = new ArrayList<>( 0 );
-
-            ITurtleUpgrade left = item.getUpgrade( stack, TurtleSide.LEFT );
-            ITurtleUpgrade right = item.getUpgrade( stack, TurtleSide.RIGHT );
-
-            // The turtle is facing towards us, so upgrades on the left are actually crafted on the right.
-            if( left != null )
-            {
-                recipes.add( horizontal(
-                    of( Ingredient.EMPTY, of( turtleWith( stack, null, right ) ), of( left.getCraftingItem() ) ),
-                    stack
-                ) );
-            }
-
-            if( right != null )
-            {
-                recipes.add( horizontal(
-                    of( Ingredient.EMPTY, of( right.getCraftingItem() ), of( turtleWith( stack, left, null ) ) ),
-                    stack
-                ) );
-            }
-
-            return cast( recipes );
-        }
-        else if( stack.getItem() instanceof ItemPocketComputer )
-        {
-            List<Shaped> recipes = new ArrayList<>( 0 );
-
-            IPocketUpgrade back = ItemPocketComputer.getUpgrade( stack );
-            if( back != null )
-            {
-                recipes.add( vertical(
-                    of( Ingredient.EMPTY, of( back.getCraftingItem() ), of( pocketWith( stack, null ) ) ),
-                    stack
-                ) );
-            }
-
-            return cast( recipes );
-        }
-        else
-        {
-            return Collections.emptyList();
-        }
-    }
 
     @SuppressWarnings( { "unchecked", "rawtypes" } )
     private static <T, U> List<T> cast( List<U> from )
     {
         return (List) from;
     }
-
-    private static ItemStack turtleWith( ItemStack stack, ITurtleUpgrade left, ITurtleUpgrade right )
-    {
-        ITurtleItem item = (ITurtleItem) stack.getItem();
-        return TurtleItemFactory.create(
-            item.getComputerID( stack ), item.getLabel( stack ), item.getColour( stack ), item.getFamily(),
-            left, right, item.getFuelLevel( stack ), item.getOverlay( stack )
-        );
-    }
-
-    private static ItemStack pocketWith( ItemStack stack, IPocketUpgrade back )
-    {
-        ItemPocketComputer item = (ItemPocketComputer) stack.getItem();
-        return PocketComputerItemFactory.create(
-            item.getComputerID( stack ), item.getLabel( stack ), item.getColour( stack ), item.getFamily(),
-            back
-        );
-    }
-
-    private static Shaped vertical( NonNullList<Ingredient> input, ItemStack result )
-    {
-        return new Shaped( 1, input.size(), input, result );
-    }
-
-    private static Shaped horizontal( NonNullList<Ingredient> input, ItemStack result )
-    {
-        return new Shaped( input.size(), 1, input, result );
-    }
-
-    private static class Shaped extends ShapedRecipe
-    {
-        private static final ResourceLocation ID = new ResourceLocation( ComputerCraft.MOD_ID, "impostor" );
-
-        Shaped( int width, int height, NonNullList<Ingredient> input, ItemStack output )
-        {
-            super( ID, null, width, height, input, output );
-        }
-
-        @Nonnull
-        @Override
-        public IRecipeSerializer<?> getSerializer()
-        {
-            throw new IllegalStateException( "Should not serialise the JEI recipe" );
-        }
-    }
-
-    private static class UpgradeInfo
-    {
-        final ItemStack stack;
-        final Ingredient ingredient;
-        final ITurtleUpgrade turtle;
-        final IPocketUpgrade pocket;
-        final IUpgradeBase upgrade;
-        ArrayList<Shaped> recipes;
-
-        UpgradeInfo( ItemStack stack, ITurtleUpgrade turtle )
-        {
-            this.stack = stack;
-            ingredient = of( stack );
-            upgrade = this.turtle = turtle;
-            pocket = null;
-        }
-
-        UpgradeInfo( ItemStack stack, IPocketUpgrade pocket )
-        {
-            this.stack = stack;
-            ingredient = of( stack );
-            turtle = null;
-            upgrade = this.pocket = pocket;
-        }
-
-        List<Shaped> getRecipes()
-        {
-            ArrayList<Shaped> recipes = this.recipes;
-            if( recipes != null ) return recipes;
-
-            recipes = this.recipes = new ArrayList<>( 4 );
-            for( ComputerFamily family : MAIN_FAMILIES )
-            {
-                if( turtle != null && TurtleUpgrades.suitableForFamily( family, turtle ) )
-                {
-                    recipes.add( horizontal(
-                        of( Ingredient.EMPTY, ingredient, of( TurtleItemFactory.create( -1, null, -1, family, null, null, 0, null ) ) ),
-                        TurtleItemFactory.create( -1, null, -1, family, null, turtle, 0, null )
-                    ) );
-                }
-
-                if( pocket != null )
-                {
-                    recipes.add( vertical(
-                        of( Ingredient.EMPTY, ingredient, of( PocketComputerItemFactory.create( -1, null, -1, family, null ) ) ),
-                        PocketComputerItemFactory.create( -1, null, -1, family, pocket )
-                    ) );
-                }
-            }
-
-            recipes.trimToSize();
-            return recipes;
-        }
-    }
 }