/** merges provided ItemStack with the first avaliable one in the container/player inventory */
protected boolean mergeItemStack(ItemStack par1ItemStack, int par2, int par3, boolean par4) {
boolean var5 = false;
int var6 = par2;
if (par4) {
var6 = par3 - 1;
}
Slot var7;
ItemStack var8;
if (par1ItemStack.isStackable()) {
while (par1ItemStack.stackSize > 0 && (!par4 && var6 < par3 || par4 && var6 >= par2)) {
var7 = (Slot) this.inventorySlots.get(var6);
var8 = var7.getStack();
if (var8 != null
&& var8.itemID == par1ItemStack.itemID
&& (!par1ItemStack.getHasSubtypes()
|| par1ItemStack.getItemDamage() == var8.getItemDamage())
&& ItemStack.func_77970_a(par1ItemStack, var8)) {
int var9 = var8.stackSize + par1ItemStack.stackSize;
if (var9 <= par1ItemStack.getMaxStackSize()) {
par1ItemStack.stackSize = 0;
var8.stackSize = var9;
var7.onSlotChanged();
var5 = true;
} else if (var8.stackSize < par1ItemStack.getMaxStackSize()) {
par1ItemStack.stackSize -= par1ItemStack.getMaxStackSize() - var8.stackSize;
var8.stackSize = par1ItemStack.getMaxStackSize();
var7.onSlotChanged();
var5 = true;
}
}
if (par4) {
--var6;
} else {
++var6;
}
}
}
if (par1ItemStack.stackSize > 0) {
if (par4) {
var6 = par3 - 1;
} else {
var6 = par2;
}
while (!par4 && var6 < par3 || par4 && var6 >= par2) {
var7 = (Slot) this.inventorySlots.get(var6);
var8 = var7.getStack();
if (var8 == null) {
var7.putStack(par1ItemStack.copy());
var7.onSlotChanged();
par1ItemStack.stackSize = 0;
var5 = true;
break;
}
if (par4) {
--var6;
} else {
++var6;
}
}
}
return var5;
}
