/**
* OLAT - Online Learning and Training<br>
* http://www.olat.org
* <p>
* Licensed under the Apache License, Version 2.0 (the "License"); <br>
* you may not use this file except in compliance with the License.<br>
* You may obtain a copy of the License at
* <p>
* http://www.apache.org/licenses/LICENSE-2.0
* <p>
* Unless required by applicable law or agreed to in writing,<br>
* software distributed under the License is distributed on an "AS IS" BASIS, <br>
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. <br>
* See the License for the specific language governing permissions and <br>
* limitations under the License.
* <p>
* Copyright (c) since 2004 at Multimedia- & E-Learning Services (MELS),<br>
* University of Zurich, Switzerland.
* <p>
*/
package org.olat.course;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.MalformedURLException;
import java.net.URL;

import org.olat.core.logging.OLog;
import org.olat.core.logging.Tracing;

/**
 * Description:<br>
 * holds information how to deploy and download a zipped repo entry.
 * 
 * <P>
 * Initial Date:  21.12.2010 <br>
 * @author guido
 */
public class DeployableCourseExport {
	
	private String courseUrl;
	//default is open for all inkl. guests
	private int access = 4;
	private Float version;
	private String identifier;
	//default for a demo course is false
	private boolean helpCourse = false;
	OLog log = Tracing.createLoggerFor(this.getClass());
	private File file;
	
	/**
	 * [spring]
	 */
	private DeployableCourseExport() {
		//
	}

	/**
	 * Downloads the file from the net given the url
	 * @return the file or null in case of error
	 */
	public File getDeployableCourseZipFile() {
		if (file == null) {
			URL url;
			try {
				url = new URL(courseUrl);
			} catch (MalformedURLException e) {
				log.error("Url is not valid: "+courseUrl);
				return null;
			}
			file = downloadZipFromUrl(url);
			return file;
			}
		return file;
	}

	public void setCourseUrl(String courseUrl) {
		this.courseUrl = courseUrl;
	}

	public int getAccess() {
		return access;
	}

	public void setAccess(int access) {
		this.access = access;
	}

	public boolean isHelpCourse() {
		return helpCourse;
	}

	public void setHelpCourse(boolean helpCourse) {
		this.helpCourse = helpCourse;
	}
	
	private File downloadZipFromUrl(URL url) {
		try {
			log.info("Downloading demo course file: "+url);
			HttpURLConnection uc = (HttpURLConnection) url.openConnection();
			int responseCode = uc.getResponseCode();
			String contentType = uc.getContentType();
			int contentLength = uc.getContentLength();
			if (responseCode != 200 || !contentType.startsWith("application/") || contentLength == -1) {
				if (responseCode != 200) {
					log.warn("Server response was not successful code: "+responseCode+" with url: " + courseUrl);
				} else if (contentLength == -1) {
					log.warn("File is empty!");
				} else if (!contentType.startsWith("application/")) {
					log.warn("File is not a binary file! ContentType is: " + contentType + " from url:" + courseUrl);
				}
				return null;
			}
			InputStream raw = uc.getInputStream();
			InputStream in = new BufferedInputStream(raw);
			byte[] data = new byte[contentLength];
			int bytesRead = 0;
			int offset = 0;
			System.out.print("downloading[");
			int tenPercent = contentLength / 10;
			int tenPercentRead = 0;
			while (offset < contentLength) {
				bytesRead = in.read(data, offset, data.length - offset);
				if (bytesRead == -1) break;
				offset += bytesRead;
				tenPercentRead += bytesRead;
				if (tenPercentRead >  tenPercent) {
					tenPercentRead = 0;
					System.out.print("===========");
				}
			}
			System.out.print("=>]");
			System.out.println("");
			in.close();
			if (offset != contentLength) { throw new IOException("Only read " + offset + " bytes; Expected " + contentLength + " bytes"); }
			
			String filename = url.getFile().substring(url.getFile().lastIndexOf('/') + 1);
			filename = System.getProperty("java.io.tmpdir")+"/"+filename;
			FileOutputStream out = new FileOutputStream(filename);
			out.write(data);
			out.flush();
			out.close();
			return new File(filename);
		} catch (Exception e) {
			log.error("Could not read file from url: "+courseUrl, e);
			return null;
		}

	}

	public Float getVersion() {
		return version;
	}

	public void setVersion(Float version) {
		this.version = version;
	}

	public void setIdentifier(String identifier) {
		this.identifier = identifier;
	}

	public String getIdentifier() {
		return identifier;
	}

}