From 099e6f47e8f2327d38da9aafa416ec20009a63cb Mon Sep 17 00:00:00 2001
From: mezz <tehgeek@gmail.com>
Date: Fri, 16 Oct 2015 11:56:22 -0700
Subject: [PATCH] Fix #893 Shift-Removing items from a machine prefers the
 hotbar

---
 .../java/forestry/core/utils/SlotUtil.java    | 96 ++++++++++++-------
 1 file changed, 60 insertions(+), 36 deletions(-)

diff --git a/src/main/java/forestry/core/utils/SlotUtil.java b/src/main/java/forestry/core/utils/SlotUtil.java
index c3afcf452..b7360148e 100644
--- a/src/main/java/forestry/core/utils/SlotUtil.java
+++ b/src/main/java/forestry/core/utils/SlotUtil.java
@@ -104,11 +104,7 @@ public abstract class SlotUtil {
 				return shiftToHotbar(inventorySlots, stackInSlot);
 			}
 		} else {
-			boolean shifted = shiftToHotbar(inventorySlots, stackInSlot);
-			if (!shifted) {
-				shifted = shiftToPlayerInventoryNoHotbar(inventorySlots, stackInSlot);
-			}
-			return shifted;
+			return shiftToPlayerInventory(inventorySlots, stackInSlot);
 		}
 	}
 
@@ -158,38 +154,31 @@ public abstract class SlotUtil {
 	}
 
 	private static boolean shiftItemStackToRange(List inventorySlots, ItemStack stackToShift, int start, int count) {
-		boolean changed = false;
-		if (stackToShift.isStackable()) {
-			for (int slotIndex = start; stackToShift.stackSize > 0 && slotIndex < start + count; slotIndex++) {
-				Slot slot = (Slot) inventorySlots.get(slotIndex);
-				ItemStack stackInSlot = slot.getStack();
-				if (stackInSlot != null && ItemStackUtil.isIdenticalItem(stackInSlot, stackToShift)) {
-					int resultingStackSize = stackInSlot.stackSize + stackToShift.stackSize;
-					int max = Math.min(stackToShift.getMaxStackSize(), slot.getSlotStackLimit());
-					if (resultingStackSize <= max) {
-						stackToShift.stackSize = 0;
-						stackInSlot.stackSize = resultingStackSize;
-						slot.onSlotChanged();
-						changed = true;
-					} else if (stackInSlot.stackSize < max) {
-						stackToShift.stackSize -= max - stackInSlot.stackSize;
-						stackInSlot.stackSize = max;
-						slot.onSlotChanged();
-						changed = true;
-					}
-				}
-			}
+		boolean changed = shiftItemStackToRangeMerge(inventorySlots, stackToShift, start, count);
+		changed |= shiftItemStackToRangeOpenSlots(inventorySlots, stackToShift, start, count);
+		return changed;
+	}
+
+	private static boolean shiftItemStackToRangeMerge(List inventorySlots, ItemStack stackToShift, int start, int count) {
+		if (stackToShift == null || !stackToShift.isStackable() || stackToShift.stackSize <= 0) {
+			return false;
 		}
-		if (stackToShift.stackSize > 0) {
-			for (int slotIndex = start; stackToShift.stackSize > 0 && slotIndex < start + count; slotIndex++) {
-				Slot slot = (Slot) inventorySlots.get(slotIndex);
-				ItemStack stackInSlot = slot.getStack();
-				if (stackInSlot == null) {
-					int max = Math.min(stackToShift.getMaxStackSize(), slot.getSlotStackLimit());
-					stackInSlot = stackToShift.copy();
-					stackInSlot.stackSize = Math.min(stackToShift.stackSize, max);
-					stackToShift.stackSize -= stackInSlot.stackSize;
-					slot.putStack(stackInSlot);
+
+		boolean changed = false;
+		for (int slotIndex = start; stackToShift.stackSize > 0 && slotIndex < start + count; slotIndex++) {
+			Slot slot = (Slot) inventorySlots.get(slotIndex);
+			ItemStack stackInSlot = slot.getStack();
+			if (stackInSlot != null && ItemStackUtil.isIdenticalItem(stackInSlot, stackToShift)) {
+				int resultingStackSize = stackInSlot.stackSize + stackToShift.stackSize;
+				int max = Math.min(stackToShift.getMaxStackSize(), slot.getSlotStackLimit());
+				if (resultingStackSize <= max) {
+					stackToShift.stackSize = 0;
+					stackInSlot.stackSize = resultingStackSize;
+					slot.onSlotChanged();
+					changed = true;
+				} else if (stackInSlot.stackSize < max) {
+					stackToShift.stackSize -= max - stackInSlot.stackSize;
+					stackInSlot.stackSize = max;
 					slot.onSlotChanged();
 					changed = true;
 				}
@@ -198,6 +187,28 @@ public abstract class SlotUtil {
 		return changed;
 	}
 
+	private static boolean shiftItemStackToRangeOpenSlots(List inventorySlots, ItemStack stackToShift, int start, int count) {
+		if (stackToShift == null || stackToShift.stackSize <= 0) {
+			return false;
+		}
+
+		boolean changed = false;
+		for (int slotIndex = start; stackToShift.stackSize > 0 && slotIndex < start + count; slotIndex++) {
+			Slot slot = (Slot) inventorySlots.get(slotIndex);
+			ItemStack stackInSlot = slot.getStack();
+			if (stackInSlot == null) {
+				int max = Math.min(stackToShift.getMaxStackSize(), slot.getSlotStackLimit());
+				stackInSlot = stackToShift.copy();
+				stackInSlot.stackSize = Math.min(stackToShift.stackSize, max);
+				stackToShift.stackSize -= stackInSlot.stackSize;
+				slot.putStack(stackInSlot);
+				slot.onSlotChanged();
+				changed = true;
+			}
+		}
+		return changed;
+	}
+
 	private static final int playerInventorySize = 9 * 4;
 	private static final int playerHotbarSize = 9;
 
@@ -209,6 +220,19 @@ public abstract class SlotUtil {
 		return SlotUtil.isSlotInRange(slotIndex, playerInventorySize - playerHotbarSize, playerInventorySize);
 	}
 
+	private static boolean shiftToPlayerInventory(List inventorySlots, ItemStack stackInSlot) {
+		int playerHotbarStart = playerInventorySize - playerHotbarSize;
+
+		// try to merge with existing stacks, hotbar first
+		boolean shifted = shiftItemStackToRangeMerge(inventorySlots, stackInSlot, playerHotbarStart, playerHotbarSize);
+		shifted |= shiftItemStackToRangeMerge(inventorySlots, stackInSlot, 0, playerHotbarStart);
+
+		// shift to open slots, hotbar first
+		shifted |= shiftItemStackToRangeOpenSlots(inventorySlots, stackInSlot, playerHotbarStart, playerHotbarSize);
+		shifted |= shiftItemStackToRangeOpenSlots(inventorySlots, stackInSlot, 0, playerHotbarStart);
+		return shifted;
+	}
+
 	private static boolean shiftToPlayerInventoryNoHotbar(List inventorySlots, ItemStack stackInSlot) {
 		int playerHotbarStart = playerInventorySize - playerHotbarSize;
 		return shiftItemStackToRange(inventorySlots, stackInSlot, 0, playerHotbarStart);