/*
 * #%L
 * BroadleafCommerce Common Libraries
 * %%
 * Copyright (C) 2009 - 2013 Broadleaf Commerce
 * %%
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *       http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * #L%
 */
package org.broadleafcommerce.common.resource.service;

import org.springframework.core.io.Resource;

/**
 * Service responsible for interacting with YUI-compressor to minify JS/CSS resources.
 * 
 * @author Andre Azzolini (apazzolini)
 */
public interface ResourceMinificationService {

    /**
     * Given the source byte[], will return a byte[] that represents the YUI-compressor minified version
     * of the byte[]. The behavior of this method is controlled via the following properties:
     * 
     * <ul>
     *  <li>minify.enabled - whether or not to actually perform minification</li>
     *  <li>minify.linebreak - if set to a value other than -1, will enforce a linebreak at that value</li>
     *  <li>minify.munge - if true, will replace variable names with shorter versions</li>
     *  <li>minify.verbose - if true, will display extra logging information to the console</li>
     *  <li>minify.preserveAllSemiColons - if true, will never remove semi-colons, even if two in a row exist</li>
     *  <li>minify.disableOptimizations - if true, will disable some micro-optimizations that are performed</li>
     * </ul>
     * 
     * @param filename
     * @param bytes
     * @return the minified bytes
     */
    public byte[] minify(String filename, byte[] bytes);

    /**
     * Indicates whether or not the system is allowed to minify bundled resources.
     * 
     * @return the value of the system property "minify.enabled"
     */
    public boolean getEnabled();

    /**
     * Indicates whether or not the system is allowed to attempt to minify individual files. This can be useful if
     * the YUI compressor is failing to minify JavaScript/CSS due to syntax errors and you are attempting to track
     * down which file is problematic. It should not be enabled in a production environment.
     * 
     * @return the value of the system property "minify.allowSingleMinification"
     */
    boolean getAllowSingleMinification();

    /**
     * Delegates to {@link #minify(Resource, String)} where the filename argument is originalResource.getFilename().
     * @param originalResource
     * @return
     */
    Resource minify(Resource originalResource);

    /**
     * Given a {@link Resource}, will return a resource that represents the YUI-compressor minified version.
     * 
     * The behavior of this method is controlled via the following properties:
     * 
     * <ul>
     *  <li>minify.enabled - whether or not to actually perform minification</li>
     *  <li>minify.linebreak - if set to a value other than -1, will enforce a linebreak at that value</li>
     *  <li>minify.munge - if true, will replace variable names with shorter versions</li>
     *  <li>minify.verbose - if true, will display extra logging information to the console</li>
     *  <li>minify.preserveAllSemiColons - if true, will never remove semi-colons, even if two in a row exist</li>
     *  <li>minify.disableOptimizations - if true, will disable some micro-optimizations that are performed</li>
     * </ul>
     * 
     * @param orginalResource
     * @param the name of resource
     * 
     * @return The minified resource
     */
    Resource minify(Resource originalResource, String filename);

}