// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you 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 com.cloud.storage.template;

public interface TemplateDownloader extends Runnable{
	

	/**
	 * Callback used to notify completion of download
	 *
	 */
	public interface DownloadCompleteCallback {
		void downloadComplete( Status status);

	}

	public static enum Status  {UNKNOWN, NOT_STARTED, IN_PROGRESS, ABORTED, UNRECOVERABLE_ERROR, RECOVERABLE_ERROR, DOWNLOAD_FINISHED, POST_DOWNLOAD_FINISHED}

	public static long DEFAULT_MAX_TEMPLATE_SIZE_IN_BYTES = 50L*1024L*1024L*1024L;
	
	/**
	 * Initiate download, resuming a previous one if required
	 * @param resume resume if necessary
	 * @param callback completion callback to be called after download is complete
	 * @return bytes downloaded
	 */
	public long download(boolean resume, DownloadCompleteCallback callback);
	
	/**
	 * @return
	 */
	public boolean stopDownload();
	
	/**
	 * @return percent of file downloaded
	 */
	public int getDownloadPercent();

	/**
	 * Get the status of the download
	 * @return status of download
	 */
	public TemplateDownloader.Status getStatus();


	/**
	 * Get time taken to download so far
	 * @return time in seconds taken to download
	 */
	public long getDownloadTime();

	/**
	 * Get bytes downloaded
	 * @return bytes downloaded so far
	 */
	public long getDownloadedBytes();

	/**
	 * Get the error if any
	 * @return error string if any
	 */
	public String getDownloadError();

	/** Get local path of the downloaded file
	 * @return local path of the file downloaded
	 */
	public String getDownloadLocalPath();

	public void setStatus(TemplateDownloader.Status status);

	public void setDownloadError(String string);

	public void setResume(boolean resume);
	
	public boolean isInited();
	
	public long getMaxTemplateSizeInBytes();

}
