/*
 * This file is part of Applied Energistics 2.
 * Copyright (c) 2013 - 2017, AlgorithmX2, All rights reserved.
 *
 * Applied Energistics 2 is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * Applied Energistics 2 is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public License
 * along with Applied Energistics 2.  If not, see <http://www.gnu.org/licenses/lgpl>.
 */

package appeng.parts.p2p;


import java.util.List;
import javax.annotation.Nonnull;
import javax.annotation.Nullable;

import net.minecraft.item.ItemStack;
import net.minecraft.tileentity.TileEntity;
import net.minecraftforge.common.capabilities.Capability;
import net.minecraftforge.common.util.LazyOptional;
import net.minecraftforge.energy.IEnergyStorage;

import appeng.api.config.PowerUnits;
import appeng.api.parts.IPartModel;
import appeng.capabilities.Capabilities;
import appeng.items.parts.PartModels;
import appeng.me.GridAccessException;


public class PartP2PFEPower extends PartP2PTunnel<PartP2PFEPower>
{
	private static final P2PModels MODELS = new P2PModels( "part/p2p/p2p_tunnel_fe" );
	private static final IEnergyStorage NULL_ENERGY_STORAGE = new NullEnergyStorage();
	private final IEnergyStorage inputHandler = new InputEnergyStorage();
	private final IEnergyStorage outputHandler = new OutputEnergyStorage();

	public PartP2PFEPower( ItemStack is )
	{
		super( is );
	}

	@PartModels
	public static List<IPartModel> getModels()
	{
		return MODELS.getModels();
	}

	@Override
	public IPartModel getStaticModels()
	{
		return MODELS.getModel( this.isPowered(), this.isActive() );
	}

	@Override
	public void onTunnelNetworkChange()
	{
		this.getHost().notifyNeighbors();
	}

	private IEnergyStorage getAttachedEnergyStorage()
	{
		LazyOptional<IEnergyStorage> energyStorageOpt = LazyOptional.empty();
		if( this.isActive() )
		{
			final TileEntity self = this.getTile();
			final TileEntity te = self.getWorld().getTileEntity( self.getPos().offset( this.getSide().getFacing() ) );

			if( te != null )
			{
				energyStorageOpt = te.getCapability( Capabilities.FORGE_ENERGY, this.getSide().getOpposite().getFacing() );
			}
		}
		return energyStorageOpt.orElse( NULL_ENERGY_STORAGE );
	}

	@SuppressWarnings("unchecked")
	@Nullable
	@Override
	public <T> LazyOptional<T> getCapability( @Nonnull Capability<T> capability )
	{
		if( capability == Capabilities.FORGE_ENERGY )
		{
			if( this.isOutput() )
			{
				return (LazyOptional<T>) LazyOptional.of(() -> this.outputHandler);
			}
			return (LazyOptional<T>) LazyOptional.of(() ->this.inputHandler);
		}
		return super.getCapability( capability );
	}

	private class InputEnergyStorage implements IEnergyStorage
	{
		@Override
		public int extractEnergy( int maxExtract, boolean simulate )
		{
			return 0;
		}

		@Override
		public int receiveEnergy( int maxReceive, boolean simulate )
		{
			int total = 0;

			try
			{
				final int outputTunnels = PartP2PFEPower.this.getOutputs().size();

				if( outputTunnels == 0 | maxReceive == 0 )
				{
					return 0;
				}

				final int amountPerOutput = maxReceive / outputTunnels;
				int overflow = amountPerOutput == 0 ? maxReceive : maxReceive % amountPerOutput;

				for( PartP2PFEPower target : PartP2PFEPower.this.getOutputs() )
				{
					final IEnergyStorage output = target.getAttachedEnergyStorage();
					final int toSend = amountPerOutput + overflow;
					final int received = output.receiveEnergy( toSend, simulate );

					overflow = toSend - received;
					total += received;
				}

				if( !simulate )
				{
					PartP2PFEPower.this.queueTunnelDrain( PowerUnits.RF, total );
				}
			}
			catch( GridAccessException ignored )
			{
			}

			return total;
		}

		@Override
		public boolean canExtract()
		{
			return false;
		}

		@Override
		public boolean canReceive()
		{
			return true;
		}

		@Override
		public int getMaxEnergyStored()
		{
			int total = 0;

			try
			{
				for( PartP2PFEPower t : PartP2PFEPower.this.getOutputs() )
				{
					total += t.getAttachedEnergyStorage().getMaxEnergyStored();
				}
			}
			catch( GridAccessException e )
			{
				return 0;
			}

			return total;
		}

		@Override
		public int getEnergyStored()
		{
			int total = 0;

			try
			{
				for( PartP2PFEPower t : PartP2PFEPower.this.getOutputs() )
				{
					total += t.getAttachedEnergyStorage().getEnergyStored();
				}
			}
			catch( GridAccessException e )
			{
				return 0;
			}

			return total;
		}
	}


	private class OutputEnergyStorage implements IEnergyStorage
	{
		@Override
		public int extractEnergy( int maxExtract, boolean simulate )
		{
			final int total = PartP2PFEPower.this.getAttachedEnergyStorage().extractEnergy( maxExtract, simulate );

			if( !simulate )
			{
				PartP2PFEPower.this.queueTunnelDrain( PowerUnits.RF, total );
			}

			return total;
		}

		@Override
		public int receiveEnergy( int maxReceive, boolean simulate )
		{
			return 0;
		}

		@Override
		public boolean canExtract()
		{
			return PartP2PFEPower.this.getAttachedEnergyStorage().canExtract();
		}

		@Override
		public boolean canReceive()
		{
			return false;
		}

		@Override
		public int getMaxEnergyStored()
		{
			return PartP2PFEPower.this.getAttachedEnergyStorage().getMaxEnergyStored();
		}

		@Override
		public int getEnergyStored()
		{
			return PartP2PFEPower.this.getAttachedEnergyStorage().getEnergyStored();
		}
	}


	private static class NullEnergyStorage implements IEnergyStorage
	{

		@Override
		public int receiveEnergy( int maxReceive, boolean simulate )
		{
			return 0;
		}

		@Override
		public int extractEnergy( int maxExtract, boolean simulate )
		{
			return 0;
		}

		@Override
		public int getEnergyStored()
		{
			return 0;
		}

		@Override
		public int getMaxEnergyStored()
		{
			return 0;
		}

		@Override
		public boolean canExtract()
		{
			return false;
		}

		@Override
		public boolean canReceive()
		{
			return false;
		}
	}
}