feat: add fluid export

(closes SquidDev-CC#247)

src/main/java/org/squiddev/plethora/integration/appliedenergistics/MethodExportFluid.java

@@ -0,0 +1,74 @@
+package org.squiddev.plethora.integration.appliedenergistics;
+
+import appeng.api.AEApi;
+import appeng.api.config.Actionable;
+import appeng.api.networking.IGrid;
+import appeng.api.networking.security.IActionHost;
+import appeng.api.networking.storage.IStorageGrid;
+import appeng.api.storage.channels.IFluidStorageChannel;
+import appeng.api.storage.data.IAEFluidStack;
+import appeng.core.AppEng;
+import appeng.me.helpers.MachineSource;
+import dan200.computercraft.api.lua.LuaException;
+import net.minecraftforge.fluids.FluidStack;
+import net.minecraftforge.fluids.capability.IFluidHandler;
+import org.squiddev.plethora.api.method.IContext;
+import org.squiddev.plethora.api.method.ITransferMethod;
+import org.squiddev.plethora.api.method.MarkerInterfaces;
+import org.squiddev.plethora.api.method.wrapper.FromContext;
+import org.squiddev.plethora.api.method.wrapper.Optional;
+import org.squiddev.plethora.api.method.wrapper.PlethoraMethod;
+
+import static org.squiddev.plethora.integration.vanilla.method.MethodsInventoryTransfer.extractFluidHandler;
+
+public final class MethodExportFluid {
+	private MethodExportFluid() {
+	}
+
+	@PlethoraMethod(
+		modId = AppEng.MOD_ID,
+		doc = "-- Export this fluid from the AE network to a tank. Returns the amount transferred."
+	)
+	@MarkerInterfaces(ITransferMethod.class)
+	public static long export(
+			IContext<IAEFluidStack> baked, @FromContext IGrid grid, @FromContext IActionHost host,
+			String toName, @Optional(defInt = Integer.MAX_VALUE) int limit
+	) throws LuaException {
+		// Find location to transfer to
+		Object location = baked.getTransferLocation(toName);
+		if (location == null) throw new LuaException("Target '" + toName + "' does not exist");
+
+		// Validate our location is valid
+		IFluidHandler to = extractFluidHandler(location);
+		if (to == null) throw new LuaException("Target '" + toName + "' is not a tank");
+
+		if (limit <= 0) throw new LuaException("Limit must be > 0");
+
+		// Find the stack to extract
+		IFluidStorageChannel channel = AEApi.instance().storage().getStorageChannel(IFluidStorageChannel.class);
+		IStorageGrid storageGrid = grid.getCache(IStorageGrid.class);
+		MachineSource source = new MachineSource(host);
+
+		// Extract said fluid
+		IAEFluidStack toExtract = baked.getTarget().copy();
+		toExtract.setStackSize(Math.min(limit, toExtract.getStackSize()));
+		toExtract = storageGrid.getInventory(channel).extractItems(toExtract, Actionable.MODULATE, source);
+		if (toExtract == null) {
+			return 0;
+		}
+
+		// Attempt to insert into the appropriate tank
+		FluidStack toInsert = toExtract.getFluidStack();
+		int extracted = toInsert.amount;
+		int transferred = to.fill(toInsert, true);
+
+		// If not everything could be inserted, replace back in the tank
+		if (transferred < extracted) {
+			FluidStack remainder = toInsert.copy();
+			remainder.amount = extracted - transferred;
+			storageGrid.getInventory(channel).injectItems(channel.createStack(remainder), Actionable.MODULATE, source);
+		}
+
+		return transferred;
+	}
+}

src/main/java/org/squiddev/plethora/integration/appliedenergistics/MethodExportItem.java

@@ -56,6 +56,9 @@ public static long export(
 		IAEItemStack toExtract = baked.getTarget().copy();
 		toExtract.setStackSize(Math.min(limit, toExtract.getDefinition().getMaxStackSize()));
 		toExtract = storageGrid.getInventory(channel).extractItems(toExtract, Actionable.MODULATE, source);
+		if (toExtract == null) {
+			return 0;
+		}
 
 		// Attempt to insert into the appropriate inventory
 		ItemStack toInsert = toExtract.createItemStack();

src/main/java/org/squiddev/plethora/integration/vanilla/method/MethodsInventoryTransfer.java

@@ -3,6 +3,8 @@
 import dan200.computercraft.api.lua.LuaException;
 import net.minecraft.item.ItemStack;
 import net.minecraftforge.common.capabilities.ICapabilityProvider;
+import net.minecraftforge.fluids.capability.CapabilityFluidHandler;
+import net.minecraftforge.fluids.capability.IFluidHandler;
 import net.minecraftforge.items.CapabilityItemHandler;
 import net.minecraftforge.items.IItemHandler;
 import net.minecraftforge.items.ItemHandlerHelper;
@@ -85,6 +87,20 @@ public static IItemHandler extractHandler(@Nonnull Object object) {
 		return null;
 	}
 
+	@Nullable
+	public static IFluidHandler extractFluidHandler(@Nonnull Object object) {
+		for (Object child : PlethoraAPI.instance().converterRegistry().convertAll(object)) {
+			if (child instanceof IFluidHandler) return (IFluidHandler) child;
+
+			if (object instanceof ICapabilityProvider) {
+				IFluidHandler handler = ((ICapabilityProvider) object).getCapability(CapabilityFluidHandler.FLUID_HANDLER_CAPABILITY, null);
+				if (handler != null) return handler;
+			}
+		}
+
+		return null;
+	}
+
 	/**
 	 * Move an item from one handler to another
 	 *