/*

 * Copyright (c) 2007-2010 Nokia Corporation and/or its subsidiary(-ies). 

 * All rights reserved.

 * This component and the accompanying materials are made available

 * under the terms of "Eclipse Public License v1.0"

 * which accompanies this distribution, and is available

 * at the URL "http://www.eclipse.org/legal/epl-v10.html".

 *

 * Initial Contributors:

 * Nokia Corporation - initial contribution.

 *

 * Contributors:

 *

 * Description:

 *

 * Copy Selection Data Fetcher gets data from file to the clipboard

 *

 */

package com.nokia.traceviewer.action;

import org.eclipse.swt.dnd.Clipboard;

import org.eclipse.swt.dnd.TextTransfer;

import org.eclipse.swt.dnd.Transfer;

import org.eclipse.ui.PlatformUI;

import com.nokia.traceviewer.engine.DataReader;

import com.nokia.traceviewer.engine.DataScrollReader;

import com.nokia.traceviewer.engine.MediaCallback;

import com.nokia.traceviewer.engine.TraceProperties;

import com.nokia.traceviewer.engine.TraceViewerGlobals;

import com.nokia.traceviewer.view.listener.SelectionProperties;

/**

 * Copies selected data to the clipboard

 * 

 */

public final class CopySelectionDataFetcher implements MediaCallback {

	/**

	 * Max number of traces to copy to clipboard

	 */

	private static int MAX_TRACES_TO_COPY = 10000;

	/**

	 * String to attach to end of the clipboard if tried to copy more than

	 * MAX_TRACES_TO_COPY traces

	 */

	private static String MAX_STRING = Messages

			.getString("CopySelectionDataFetcher.MaxTracesLine1") //$NON-NLS-1$

			+ " " //$NON-NLS-1$

			+ MAX_TRACES_TO_COPY + " " //$NON-NLS-1$

			+ Messages.getString("CopySelectionDataFetcher.MaxTracesLine2"); //$NON-NLS-1$

	/**

	 * Buffer to gather data to

	 */

	private final StringBuffer dataBuffer;

	/**

	 * Tells how many traces to drop from the beginning

	 */

	private int tracesToDrop;

	/**

	 * Tells how many traces to get totally

	 */

	private int tracesToGet;

	/**

	 * Trace count by this far

	 */

	private int traceCount;

	/**

	 * System Clipboard

	 */

	private final Clipboard clipboard;

	/**

	 * Own data reader reading the file

	 */

	private DataScrollReader dataReader;

	/**

	 * If already processing, don't start new process

	 */

	private boolean processing;

	/**

	 * Constructor

	 */

	public CopySelectionDataFetcher() {

		traceCount = 0;

		dataBuffer = new StringBuffer();

		clipboard = new Clipboard(PlatformUI.getWorkbench().getDisplay());

	}

	/*

	 * (non-Javadoc)

	 * 

	 * @see

	 * com.nokia.traceviewer.engine.MediaCallback#processTrace(com.nokia.traceviewer

	 * .engine.TraceProperties)

	 */

	public void processTrace(TraceProperties properties) {

		traceCount++;

		// Process traces we want to clipboard

		if (traceCount > tracesToDrop

				&& traceCount - tracesToDrop <= tracesToGet) {

			// Null timestamp from first trace

			if (traceCount == tracesToDrop + 1) {

				TraceViewerGlobals.getTraceViewer().getDataProcessorAccess()

						.getTimestampParser().nullPreviousTimestamp();

			}

			// Parse timestamp

			TraceViewerGlobals.getTraceViewer().getDataProcessorAccess()

					.getTimestampParser().processData(properties);

			// If binary trace, decode it

			if (properties.binaryTrace) {

				TraceViewerGlobals.getTraceViewer().getDataProcessorAccess()

						.getDecoder().processData(properties);

			}

			// Append trace to buffer

			appendTraceToBuffer(properties);

		}

		// Last trace

		if (properties.lastTrace) {

			// Lines has been received, if there are MAX_TRACES_TO_COPY

			// Also add a note to user in the end of the data

			if (tracesToGet == MAX_TRACES_TO_COPY) {

				dataBuffer.append(MAX_STRING);

			}

			// Copy data to clipboard

			copyBufferToClipboard();

		}

	}

	/**

	 * Appends trace to buffer

	 * 

	 * @param trace

	 *            trace properties

	 */

	private void appendTraceToBuffer(TraceProperties trace) {

		// Check how many characters to skip and take before starting the first

		// and last trace

		int skip = 0;

		int take = 0;

		if (SelectionProperties.firstClickedLine <= SelectionProperties.lastClickedLine) {

			skip = SelectionProperties.firstClickedLineCaretOffset;

			take = SelectionProperties.lastClickedLineCaretOffset;

		} else {

			skip = SelectionProperties.lastClickedLineCaretOffset;

			take = SelectionProperties.firstClickedLineCaretOffset;

		}

		// First trace

		if (traceCount == tracesToDrop + 1) {

			StringBuffer str = new StringBuffer();

			addTraceTextToBuffer(trace, str);

			if (str.length() > skip) {

				str.delete(0, skip);

			} else {

				str.setLength(0);

			}

			dataBuffer.append(str);

			dataBuffer.append('\r');

			dataBuffer.append('\n');

			// Last trace

		} else if (traceCount - tracesToDrop == tracesToGet) {

			StringBuffer str = new StringBuffer();

			addTraceTextToBuffer(trace, str);

			if (str.length() > take) {

				str.setLength(take);

			}

			dataBuffer.append(str);

			if (traceCount - tracesToDrop == MAX_TRACES_TO_COPY) {

				dataBuffer.append('\r');

				dataBuffer.append('\n');

			}

			// Middle trace

		} else {

			addTraceTextToBuffer(trace, dataBuffer);

			dataBuffer.append('\r');

			dataBuffer.append('\n');

		}

	}

	/**

	 * Adds trace text to string buffer

	 * 

	 * @param trace

	 *            trace to be added

	 * @param str

	 *            string buffer

	 */

	private void addTraceTextToBuffer(TraceProperties trace, StringBuffer str) {

		// Traces missing

		if (trace.bTraceInformation.isTraceMissing()) {

			str.append(TraceViewerActionUtils.TRACES_DROPPED_MSG);

		}

		// Insert timestamp

		if (trace.timestampString != null) {

			str.append(trace.timestampString);

			str.append(TraceViewerGlobals.getTraceViewer()

					.getDataProcessorAccess().getTimestampParser()

					.getTimeFromPreviousString(trace.timeFromPreviousTrace));

			str.append('\t');

		}

		// Insert trace string

		if (trace.traceString != null) {

			str.append(trace.traceString);

			if (trace.traceComment != null) {

				str.append(TraceViewerActionUtils.COMMENT_PREFIX);

				str.append(trace.traceComment);

			}

		}

	}

	/**

	 * Copies dataBuffer to clipboard

	 */

	private void copyBufferToClipboard() {

		// Copy text to clipboard

		PlatformUI.getWorkbench().getDisplay().asyncExec(new Runnable() {

			public void run() {

				try {

					String data = dataBuffer.toString();

					clipboard.setContents(new Object[] { data },

							new Transfer[] { TextTransfer.getInstance() });

				} finally {

					// Free the memory

					dataBuffer.setLength(0);

					processing = false;

				}

			}

		});

	}

	/**

	 * Starts gathering data

	 */

	public void startGatheringData() {

		if (!processing) {

			processing = true;

			dataBuffer.setLength(0);

			traceCount = 0;

			int fromTrace;

			int toTrace;

			if (SelectionProperties.firstClickedLine < SelectionProperties.lastClickedLine) {

				fromTrace = SelectionProperties.firstClickedLine;

				toTrace = SelectionProperties.lastClickedLine;

			} else {

				fromTrace = SelectionProperties.lastClickedLine;

				toTrace = SelectionProperties.firstClickedLine;

			}

			// Get the file position having given offset

			int index = TraceViewerGlobals.getTraceViewer()

					.getDataReaderAccess().getCurrentDataReader().getFileMap()

					.getIndexFromOffset(fromTrace);

			long pos = TraceViewerGlobals.getTraceViewer()

					.getDataReaderAccess().getCurrentDataReader().getFileMap()

					.getItem(index).longValue();

			int startTrace = index * TraceViewerGlobals.blockSize;

			// Calculate how many traces to drop from start

			tracesToDrop = fromTrace - startTrace;

			tracesToGet = toTrace - fromTrace + 1;

			if (tracesToGet > MAX_TRACES_TO_COPY) {

				tracesToGet = MAX_TRACES_TO_COPY;

			}

			// Number of blocks

			int numberOfBlocks = (tracesToGet / TraceViewerGlobals.blockSize) + 1;

			if (numberOfBlocks * TraceViewerGlobals.blockSize - tracesToDrop < tracesToGet) {

				numberOfBlocks++;

			}

			// Create own data reader if it doesn't exist and start it

			dataReader = TraceViewerGlobals.getTraceViewer()

					.getDataReaderAccess().startOwnDataReader(dataReader, this,

							numberOfBlocks, pos, startTrace, false);

		}

	}

	/*

	 * (non-Javadoc)

	 * 

	 * @see

	 * com.nokia.traceviewer.engine.MediaCallback#endOfFile(com.nokia.traceviewer

	 * .engine.DataReader)

	 */

	public void endOfFile(DataReader reader) {

	}

	/*

	 * (non-Javadoc)

	 * 

	 * @see com.nokia.traceviewer.engine.MediaCallback#dataHandleChanged()

	 */

	public void dataHandleChanged() {

		if (dataReader != null) {

			dataReader.shutdown();

			dataReader = null;

		}

	}

}