ActuallyAdditions/src/main/java/de/ellpeck/actuallyadditions/mod/tile/TileEntityInventoryBase.java

/*
 * This file ("TileEntityInventoryBase.java") is part of the Actually Additions mod for Minecraft.
 * It is created and owned by Ellpeck and distributed
 * under the Actually Additions License to be found at
 * http://ellpeck.de/actaddlicense
 * View the source code at https://github.com/Ellpeck/ActuallyAdditions
 *
 * © 2015-2016 Ellpeck
 */

package de.ellpeck.actuallyadditions.mod.tile;

import de.ellpeck.actuallyadditions.mod.util.ItemStackHandlerCustom;
import de.ellpeck.actuallyadditions.mod.util.StackUtil;
import net.minecraft.item.ItemStack;
import net.minecraft.nbt.NBTTagCompound;
import net.minecraft.nbt.NBTTagList;
import net.minecraft.util.EnumFacing;
import net.minecraft.util.math.MathHelper;
import net.minecraftforge.items.IItemHandler;
import net.minecraftforge.items.IItemHandlerModifiable;
import net.minecraftforge.items.ItemStackHandler;

public abstract class TileEntityInventoryBase extends TileEntityBase{

    public final ItemStackHandlerCustom slots;

    public TileEntityInventoryBase(int slots, String name){
        super(name);

        this.slots = new ItemStackHandlerCustom(slots){
            @Override
            public boolean canInsert(ItemStack stack, int slot){
                return TileEntityInventoryBase.this.isItemValidForSlot(slot, stack);
            }

            @Override
            public boolean canExtract(ItemStack stack, int slot){
                return TileEntityInventoryBase.this.canExtractItem(slot, stack);
            }

            @Override
            protected int getStackLimit(int slot, ItemStack stack){
                return TileEntityInventoryBase.this.getMaxStackSizePerSlot(slot, stack);
            }

            @Override
            protected void onContentsChanged(int slot){
                super.onContentsChanged(slot);
                TileEntityInventoryBase.this.markDirty();
            }
        };
    }

    public static void saveSlots(IItemHandler slots, NBTTagCompound compound){
        if(slots != null && slots.getSlots() > 0){
            NBTTagList tagList = new NBTTagList();
            for(int i = 0; i < slots.getSlots(); i++){
                ItemStack slot = slots.getStackInSlot(i);
                NBTTagCompound tagCompound = new NBTTagCompound();
                if(StackUtil.isValid(slot)){
                    slot.writeToNBT(tagCompound);
                }
                tagList.appendTag(tagCompound);
            }
            compound.setTag("Items", tagList);
        }
    }

    public static void loadSlots(IItemHandlerModifiable slots, NBTTagCompound compound){
        if(slots != null && slots.getSlots() > 0){
            NBTTagList tagList = compound.getTagList("Items", 10);
            for(int i = 0; i < slots.getSlots(); i++){
                NBTTagCompound tagCompound = tagList.getCompoundTagAt(i);
                slots.setStackInSlot(i, tagCompound != null && tagCompound.hasKey("id") ? new ItemStack(tagCompound) : StackUtil.getNull());
            }
        }
    }

    @Override
    public void writeSyncableNBT(NBTTagCompound compound, NBTType type){
        super.writeSyncableNBT(compound, type);
        if(type == NBTType.SAVE_TILE || (type == NBTType.SYNC && this.shouldSyncSlots())){
            saveSlots(this.slots, compound);
        }
    }

    @Override
    public IItemHandler getItemHandler(EnumFacing facing){
        return this.slots;
    }

    public boolean isItemValidForSlot(int slot, ItemStack stack){
        return true;
    }

    public boolean canExtractItem(int slot, ItemStack stack){
        return true;
    }

    public int getMaxStackSizePerSlot(int slot, ItemStack stack){
        return stack.getMaxStackSize();
    }

    public boolean shouldSyncSlots(){
        return false;
    }

    @Override
    public int getComparatorStrength(){
        int i = 0;
        float f = 0;

        for(int j = 0; j < this.slots.getSlots(); ++j){
            ItemStack stack = this.slots.getStackInSlot(j);

            if(StackUtil.isValid(stack)){
                f += (float)StackUtil.getStackSize(stack)/(float)Math.min(this.getMaxStackSizePerSlot(j, stack), stack.getMaxStackSize());
                i++;
            }
        }

        f = f/(float)this.slots.getSlots();
        return MathHelper.floor(f*14.0F)+(i > 0 ? 1 : 0);
    }

    @Override
    public void readSyncableNBT(NBTTagCompound compound, NBTType type){
        super.readSyncableNBT(compound, type);
        if(type == NBTType.SAVE_TILE || (type == NBTType.SYNC && this.shouldSyncSlots())){
            loadSlots(this.slots, compound);
        }
    }
}