/*

* 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.data;

import java.util.ArrayList;

import java.util.List;

import java.util.Map;

import com.nokia.s60tools.crashanalyser.model.*;

import com.nokia.s60tools.crashanalyser.containers.ErrorLibraryError;

import com.nokia.s60tools.crashanalyser.interfaces.IErrorLibraryObserver;

import org.eclipse.core.runtime.IProgressMonitor;

import org.eclipse.core.runtime.IStatus;

import org.eclipse.core.runtime.Status;

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

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

/**

 * ErrorLibrary class contains all error descriptions. It contains

 * a list of errors, panics and panic categories. 

 *

 */

public final class ErrorLibrary extends Job {

	private static ErrorLibrary contentProvider = null;

	Map<String, ErrorLibraryError> errors = null;

	Map<String, ErrorLibraryError> panics = null;

	Map<String, ErrorLibraryError> categories = null;

	List<IErrorLibraryObserver> observers = null;

	boolean errorsRead = false;

	boolean running = false;

	ILock accessLock = null;

	ILock queryLock = null;

	/**

	 * a singleton constructor

	 * @param observer 

	 * @return a ErrorLibrary instance

	 */

	public static ErrorLibrary getInstance(IErrorLibraryObserver observer) {

		if (contentProvider == null) {

			contentProvider = new ErrorLibrary();

		}

		contentProvider.run(observer);

		return contentProvider;

	}

	/**

	 * private constructor

	 */

	private ErrorLibrary() {

		super("Errors container");

		accessLock = Job.getJobManager().newLock();

		queryLock = Job.getJobManager().newLock();

		setPriority(Job.LONG);

		setUser(false);

	}

	/**

	 * Starts the errors reading job

	 * @param observer

	 */

	void run(IErrorLibraryObserver observer) {

		accessLock.acquire();

		addObserver(observer);

		try {

			if (running)

				return;

			else

				running = true;

		} finally {

			accessLock.release();

		}

		schedule(100);		

	}

	public boolean isReady() {

		return errorsRead;

	}

	/**

	 * Returns list of errors

	 * @return list of errors

	 */

	public ErrorLibraryError[] getErrors() {

		queryLock.acquire();

		try {

			if (errors == null)

				return new ErrorLibraryError[0];

			return errors.values().toArray(new ErrorLibraryError[errors.size()]);

		} finally {

			queryLock.release();

		}

	}

	/**

	 * Returns list of panics

	 * @return list of panics

	 */

	public ErrorLibraryError[] getPanics() {

		queryLock.acquire();

		try {

			if (panics == null)

				return new ErrorLibraryError[0];

			return panics.values().toArray(new ErrorLibraryError[panics.size()]);

		} finally {

			queryLock.release();

		}

	}

	/**

	 * Returns list of panic categories

	 * @return list of panic categories

	 */

	public ErrorLibraryError[] getCategories() {

		queryLock.release();

		try {

			if (categories == null)

				return new ErrorLibraryError[0];

		return categories.values().toArray(new ErrorLibraryError[categories.size()]);

		} finally {

			queryLock.release();

		}

	}

	/**

	 * Searches a description for given panic code

	 * @param category e.g. USER

	 * @param id e.g. 46

	 * @return description for given panic. "" if not found.

	 */

	public String getPanicDescription(String category, String id) {

		queryLock.acquire();

		try {

			String retval = "";

			if (panics != null && panics.containsKey(category+id)) {

				retval = panics.get(category+id).getDescription();

			}

			return retval;

		} finally {

			queryLock.release();

		}

	}

	/**

	 * Searches a description for given error code

	 * @param value e.g. -1 or KErrNotFound etc.

	 * @return description for given error. "" if not found.

	 */

	public String getErrorDescription(String value) {

		queryLock.acquire();

		try {

			String retval = "";

			if (errors != null && errors.containsKey(value)) {

				retval = errors.get(value).getDescription();

			}

			return retval;

		} finally {

			queryLock.release();

		}

	}

	/**

	 * Adds a new error library observer

	 * @param observer

	 */

	void addObserver(IErrorLibraryObserver observer) {

		try {

			if (observers == null)

				observers = new ArrayList<IErrorLibraryObserver>();

			if (observer != null && !observers.contains(observer)) {

				try {

					observers.add(observer);

				} catch (Exception e) {

					e.printStackTrace();

				}

			}

		} catch (Exception e) {

			e.printStackTrace();

		}

	}

	/**

	 * Notifies observers that error library is ready to be used

	 */

	void errorReaderReady() {

		try {

			while (!observers.isEmpty()) {

				IErrorLibraryObserver observer = observers.get(0);

				observer.errorLibraryReady();

				observers.remove(observer);

			}

		} catch (Exception e) {

			e.printStackTrace();

		}

		running = false;

	}

	@Override

	protected IStatus run(IProgressMonitor arg0) {

		try {

			// if errors haven't already been read, read errors

			if (!errorsRead) {

				ErrorsXmlReader reader = new ErrorsXmlReader();

				reader.readAll();

				errors = reader.getErrorsOwnership();

				panics = reader.getPanicsOwnership();

				categories = reader.getCategoriesOwnership();

				errorsRead = true;

			}

		} catch (Exception e) {

			e.printStackTrace();

		}

		accessLock.acquire();

		errorReaderReady();

		accessLock.release();

		return Status.OK_STATUS;

	}

}