/*
 * This file is part of Applied Energistics 2.
 * Copyright (c) 2013 - 2014, 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.client.render.model;


import java.util.EnumMap;
import java.util.List;

import com.google.common.collect.ImmutableList;
import com.google.common.collect.Lists;

import net.minecraft.util.EnumFacing;
import net.minecraft.util.math.Vec3d;


// TODO: Investigate use of CubeBuilder instead
final class RenderHelper
{

	private static EnumMap<EnumFacing, List<Vec3d>> cornersForFacing = generateCornersForFacings();

	private RenderHelper()
	{

	}

	static List<Vec3d> getFaceCorners( EnumFacing side )
	{
		return cornersForFacing.get( side );
	}

	private static EnumMap<EnumFacing, List<Vec3d>> generateCornersForFacings()
	{
		EnumMap<EnumFacing, List<Vec3d>> result = new EnumMap<>( EnumFacing.class );

		for( EnumFacing facing : EnumFacing.values() )
		{
			List<Vec3d> corners;

			float offset = ( facing.getAxisDirection() == EnumFacing.AxisDirection.NEGATIVE ) ? 0 : 1;

			switch( facing.getAxis() )
			{
				default:
				case X:
					corners = Lists.newArrayList( new Vec3d( offset, 1, 1 ), new Vec3d( offset, 0, 1 ), new Vec3d( offset, 0, 0 ), new Vec3d( offset, 1, 0 ) );
					break;
				case Y:
					corners = Lists.newArrayList( new Vec3d( 1, offset, 1 ), new Vec3d( 1, offset, 0 ), new Vec3d( 0, offset, 0 ), new Vec3d( 0, offset, 1 ) );
					break;
				case Z:
					corners = Lists.newArrayList( new Vec3d( 0, 1, offset ), new Vec3d( 0, 0, offset ), new Vec3d( 1, 0, offset ), new Vec3d( 1, 1, offset ) );
					break;
			}

			if( facing.getAxisDirection() == EnumFacing.AxisDirection.NEGATIVE )
			{
				corners = Lists.reverse( corners );
			}

			result.put( facing, ImmutableList.copyOf( corners ) );
		}

		return result;
	}

	private static Vec3d adjust( Vec3d vec, EnumFacing.Axis axis, double delta )
	{
		switch( axis )
		{
			default:
			case X:
				return new Vec3d( vec.xCoord + delta, vec.yCoord, vec.zCoord );
			case Y:
				return new Vec3d( vec.xCoord, vec.yCoord + delta, vec.zCoord );
			case Z:
				return new Vec3d( vec.xCoord, vec.yCoord, vec.zCoord + delta );
		}
	}
}