/*
 * 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 appeng.api.recipes.IRecipeHandler;
import appeng.recipes.CustomRecipeConfig;
import appeng.recipes.loader.ConfigLoader;
import appeng.recipes.loader.JarLoader;
import appeng.recipes.loader.RecipeResourceCopier;
import com.google.common.base.Preconditions;
import org.apache.commons.io.FileUtils;

/**
 * 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");
        }
    }
}