/*
 * This file is part of Applied Energistics 2.
 * Copyright (c) 2013 - 2015, 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.core;


import java.io.File;
import java.io.IOException;
import java.net.URISyntaxException;

import javax.annotation.Nonnull;

import com.google.common.base.Preconditions;

import org.apache.commons.io.FileUtils;

import appeng.api.recipes.IRecipeHandler;
import appeng.recipes.CustomRecipeConfig;
import appeng.recipes.loader.ConfigLoader;
import appeng.recipes.loader.JarLoader;
import appeng.recipes.loader.RecipeResourceCopier;


/**
 * handles the decision if recipes should be loaded from jar, loaded from file system or force copied from jar
 *
 * @author thatsIch
 * @version rv3 - 12.05.2015
 * @since rv3 12.05.2015
 */
public class RecipeLoader implements Runnable
{
	/**
	 * recipe path in the jar
	 */
	private static final String ASSETS_RECIPE_PATH = "/assets/appliedenergistics2/recipes/";

	@Nonnull
	private final IRecipeHandler handler;
	@Nonnull
	private final CustomRecipeConfig config;
	@Nonnull
	private final File recipeDirectory;

	/**
	 * @param config configuration for the knowledge how to handle the loading process
	 * @param handler handler to load the recipes
	 *
	 * @throws NullPointerException if handler is <tt>null</tt>
	 */
	public RecipeLoader( @Nonnull final File recipeDirectory, @Nonnull final CustomRecipeConfig config, @Nonnull final IRecipeHandler handler )
	{
		this.recipeDirectory = Preconditions.checkNotNull( recipeDirectory );
		Preconditions.checkArgument( !recipeDirectory.isFile() );
		this.config = Preconditions.checkNotNull( config );
		this.handler = Preconditions.checkNotNull( handler );
	}

	@Override
	public final void run()
	{
		if( this.config.isEnabled() )
		{
			// setup copying
			final RecipeResourceCopier copier = new RecipeResourceCopier( "assets/appliedenergistics2/recipes/" );

			final File generatedRecipesDir = new File( this.recipeDirectory, "generated" );
			final File userRecipesDir = new File( this.recipeDirectory, "user" );

			// generates generated and user recipes dir
			// will clean the generated every time to keep it up to date
			// copies over the recipes in the jar over to the generated folder
			// copies over the readmes
			try
			{
				FileUtils.forceMkdir( generatedRecipesDir );
				FileUtils.forceMkdir( userRecipesDir );
				FileUtils.cleanDirectory( generatedRecipesDir );

				copier.copyTo( ".recipe", generatedRecipesDir );
				copier.copyTo( ".html", this.recipeDirectory );

				// parse recipes prioritising the user scripts by using the generated as template
				this.handler.parseRecipes( new ConfigLoader( generatedRecipesDir, userRecipesDir ), "index.recipe" );
			}
			// on failure use jar parsing
			catch( final IOException e )
			{
				AELog.debug( e );
				this.handler.parseRecipes( new JarLoader( ASSETS_RECIPE_PATH ), "index.recipe" );
			}
			catch( final URISyntaxException e )
			{
				AELog.debug( e );
				this.handler.parseRecipes( new JarLoader( ASSETS_RECIPE_PATH ), "index.recipe" );
			}
		}
		else
		{
			this.handler.parseRecipes( new JarLoader( ASSETS_RECIPE_PATH ), "index.recipe" );
		}
	}
}