/*
 * Copyright 2009-2010 the original author or authors.
 *
 * 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.
 */
package org.springframework.batch.admin.web.freemarker;

import java.io.File;
import java.io.IOException;

import org.springframework.core.io.Resource;
import org.springframework.ui.freemarker.SpringTemplateLoader;
import org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer;

import freemarker.cache.FileTemplateLoader;
import freemarker.cache.TemplateLoader;

public class HippyFreeMarkerConfigurer extends FreeMarkerConfigurer {
	
	@Override
	protected TemplateLoader getTemplateLoaderForPath(String templateLoaderPath) {
		if (isPreferFileSystemAccess() || templateLoaderPath.startsWith("/WEB-INF")) {
			// Try to load via the file system, fall back to SpringTemplateLoader
			// (for hot detection of template changes, if possible).
			try {
				Resource path = getResourceLoader().getResource(templateLoaderPath);
				File file = path.getFile();  // will fail if not resolvable in the file system
				if (logger.isDebugEnabled()) {
					logger.debug(
							"Template loader path [" + path + "] resolved to file path [" + file.getAbsolutePath() + "]");
				}
				return new FileTemplateLoader(file);
			}
			catch (IOException ex) {
				if (logger.isDebugEnabled()) {
					logger.debug("Cannot resolve template loader path [" + templateLoaderPath +
							"] to [java.io.File]: using SpringTemplateLoader as fallback");
				}
				return new SpringTemplateLoader(getResourceLoader(), templateLoaderPath);
			}
		}
		else {
			// Always load via SpringTemplateLoader (without hot detection of template changes).
			logger.debug("File system access not preferred: using SpringTemplateLoader");
			return new SpringTemplateLoader(getResourceLoader(), templateLoaderPath);
		}
	}

}