package ftp;

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

import javax.swing.JOptionPane;
import javax.swing.SwingWorker;

import models.Image;

import org.apache.log4j.Logger;
import org.openslx.filetransfer.UploadStatusCallback;
import org.openslx.filetransfer.Uploader;

/**
 * Executes the file upload in a background thread and updates progress to
 * listeners that implement the java.beans.PropertyChangeListener interface.
 * 
 * @author www.codejava.net
 * 
 */
public class UploadTask extends SwingWorker<Void, Void> {

	/**
	 * Logger instance for this class.
	 */
	private final static Logger LOGGER = Logger.getLogger(UploadTask.class);

	private static final double UPDATE_INTERVAL_SECONDS = 0.6;
	private static final double UPDATE_INTERVAL_MS = UPDATE_INTERVAL_SECONDS * 1000;
	private static final double BYTES_PER_MIB = 1024 * 1024;

	private final String host;
	private final int port;
	private final String uploadToken;
	private final File uploadFile;
	private boolean success = false;

	public UploadTask(String host, int port, String uploadToken, File uploadFile) {
		// TODO: SSL
		this.host = host;
		this.port = port;
		this.uploadToken = uploadToken;
		this.uploadFile = uploadFile;

	}

	/**
	 * Executed in background thread
	 */
	@Override
	protected Void doInBackground() {
		Uploader upload = null;
		try {
			upload = new Uploader(host, port, null, uploadToken); // TODO: SSL

			final Uploader ul = upload;
			final long fileSize = Image.Filesize = uploadFile.length();
			firePropertyChange("filesize", 0, fileSize); // Updates GUI

			final boolean ret = upload.upload(uploadFile.getAbsolutePath(), new UploadStatusCallback() {
				// progress counter
				private long totalBytesRead = 0;
				// initialize the counters needed for speed calculations
				private long lastUpdate = 0;
				private long lastBytes = 0;
				private long currentBytes = 0;

				@Override
				public void uploadProgress(long bytesSent) {
					totalBytesRead += bytesSent;
					currentBytes += bytesSent;
					final long now = System.currentTimeMillis();
					if (lastUpdate + UPDATE_INTERVAL_MS < now) {
						final int percentCompleted = (int) ((totalBytesRead * 100) / fileSize);
						setProgress(percentCompleted);
						lastBytes = (lastBytes * 2 + currentBytes) / 3;
						final double speed = lastBytes / UPDATE_INTERVAL_SECONDS;
						firePropertyChange("speed", 0, speed / BYTES_PER_MIB);
						firePropertyChange("bytesread", 0, totalBytesRead);
						lastUpdate = now;
						currentBytes = 0;
					}
				}

				@Override
				public void uploadError(String message) {
					JOptionPane.showMessageDialog(null, "Error uploading file: " + message, "Error",
							JOptionPane.ERROR_MESSAGE);
					ul.close(null);
				}
			});

			// if the upload succeeded, set the progress to 100% manually again here to make
			// sure the GUI knows about it.
			if (ret) {
				setProgress(100);
				firePropertyChange("bytesread", 0, uploadFile.length());
				firePropertyChange("success", false, true);
				success = true;
			}
		} catch (IOException e) {
			JOptionPane.showMessageDialog(null, "Error uploading file: " + e.getMessage(), "Error",
					JOptionPane.ERROR_MESSAGE);
			LOGGER.error("Upload of " + uploadFile.getAbsolutePath() + " failed!", e);
		} finally {
			if (upload != null)
				upload.close(null);
		}

		return null;
	}

	/**
	 * Executed in Swing's event dispatching thread
	 */
	@Override
	protected void done() {
		if (isCancelled())
			return;
		if (success) {
			LOGGER.info("Datei erfolgreich hochgeladen.");
			JOptionPane.showMessageDialog(null, "Datei erfolgreich hochgeladen.", "Message",
					JOptionPane.INFORMATION_MESSAGE);
		} else {
			LOGGER.error("Datei wurde unvollständig hochgeladen.");
			JOptionPane.showMessageDialog(null, "Datei wurde unvollständig hochgeladen. Bitte wiederholen.",
					"Message", JOptionPane.INFORMATION_MESSAGE);
		}
	}
}