/*

* Copyright (c) 2008 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:

*

*/

package com.nokia.s60tools.crashanalyser.model;

import org.eclipse.core.runtime.IProgressMonitor;

import org.eclipse.core.runtime.IStatus;

import org.eclipse.core.runtime.Status;

import org.eclipse.core.runtime.jobs.Job;

import org.eclipse.swt.widgets.Display;

import java.io.File;

import java.io.FileInputStream;

import java.io.InputStreamReader;

import java.io.BufferedReader;

import java.util.regex.Pattern;

import java.util.regex.Matcher;

import com.nokia.s60tools.crashanalyser.ui.views.MainView;

import com.nokia.s60tools.crashanalyser.files.PanicFile;

/**

 * This class listens emulator for panics. 

 *

 */

public class EmulatorListener extends Job {

	static final int POLL_INTERVAL = 10000; // 10 seconds

	boolean listening = false;

	String epocWindOutPath = "";

	long previousFileSize = -1;

	int readLines = 0;

	Pattern panicParserPattern = Pattern.compile("^\\s*(\\S*)\\s*Thread\\s*(\\S*)\\s*Panic\\s*(\\S*)\\s*(\\S*).*");

	/**

	 * Constructor

	 */

	public EmulatorListener() {

		super("Crash Analyser - Emulator Listener");

		epocWindOutPath = FileOperations.addSlashToEnd(System.getenv("TEMP"));

		epocWindOutPath += "epocwind.out";

	}

	/**

	 * Starts listening emulator

	 */

	public void start() {

		if (listening)

			return;		

		listening = true;

		setPriority(Job.LONG);

		setSystem(true);

		setUser(false);

		schedule();		

	}

	/**

	 * Stops listening emulator

	 */

	public void stop() {

		listening = false;

		previousFileSize = -1;

		readLines = 0;

		cancel();

	}

	void reSchedule() {

		Runnable refreshRunnable = new Runnable(){

			public void run(){

				cancel();

				schedule(POLL_INTERVAL);

			}

		};

		Display.getDefault().asyncExec(refreshRunnable);        		

	}

	@Override

	protected IStatus run(IProgressMonitor arg0) {

		try {

			boolean filesAdded = false;

			File epocwind = new File(epocWindOutPath);

			if (epocwind.exists()) {

				// epocwind.out has not yet been read

				if (previousFileSize == -1) {

					previousFileSize = epocwind.length();

				// epocwind.out has changes

				} else if (epocwind.length() > previousFileSize) {

					FileInputStream fis = new FileInputStream(epocwind);

					BufferedReader br = new BufferedReader(new InputStreamReader(fis));

					br.skip(readLines);

					String line = "";

					// read all new lines in epocwind.out

					while ((line = br.readLine()) != null) {

						readLines++;

						if (handleLine(line))

							filesAdded = true;

					}

					previousFileSize = epocwind.length();

				// new epocwind.out file

				} else if (epocwind.length() < previousFileSize){

					previousFileSize = 0;

					readLines = 0;

				}

				// if panics were found, update main view

				if (filesAdded)

					MainView.showOrRefresh();

			}

		} catch (Exception e) {

			e.printStackTrace();

		}

		reSchedule();

		return Status.OK_STATUS;

	}

	/**

	 * If line contains a panic, writes it to xml file

	 * @param line epocwind.out file line

	 * @return true if line contained a panic, false if not

	 */

	boolean handleLine(String line) {

		Matcher matcher = panicParserPattern.matcher(line);

		if (matcher.find()) {

			PanicFile.WritePanicFile(matcher.group(1),

									 matcher.group(2),

									 matcher.group(3),

									 matcher.group(4));

			return true;

		}	

		return false;

	}

}