/*******************************************************************************
 * Copyright (c) 2000, 2008 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.pde.internal.ui.launcher;

import java.io.File;
import java.util.ArrayList;
import org.eclipse.core.filesystem.EFS;
import org.eclipse.core.filesystem.IFileStore;
import org.eclipse.core.runtime.*;
import org.eclipse.debug.core.*;
import org.eclipse.debug.core.model.IProcess;
import org.eclipse.jface.dialogs.IDialogConstants;
import org.eclipse.jface.dialogs.MessageDialog;
import org.eclipse.pde.internal.ui.*;
import org.eclipse.swt.widgets.Display;
import org.eclipse.ui.*;
import org.eclipse.ui.ide.IDE;
import org.eclipse.ui.internal.views.log.LogView;

public class LaunchListener implements ILaunchListener, IDebugEventSetListener {
	private ArrayList managedLaunches;
	// maximum log file size
	public static final long MAX_FILE_LENGTH = 1024 * 1024;
	// different ways to open the error log
	public static final int OPEN_IN_ERROR_LOG_VIEW = 0;
	public static final int OPEN_IN_SYSTEM_EDITOR = 1;

	public LaunchListener() {
		managedLaunches = new ArrayList();
	}

	public void manage(ILaunch launch) {
		if (managedLaunches.size() == 0)
			hookListener(true);
		if (!managedLaunches.contains(launch))
			managedLaunches.add(launch);
	}

	/**
	 * @see org.eclipse.debug.core.ILaunchesListener#launchesRemoved(org.eclipse.debug.core.ILaunch)
	 */
	public void launchRemoved(ILaunch launch) {
		update(launch, true);
	}

	/**
	 * @see org.eclipse.debug.core.ILaunchesListener#launchesAdded(org.eclipse.debug.core.ILaunch)
	 */
	public void launchAdded(ILaunch launch) {
	}

	/**
	 * @see org.eclipse.debug.core.ILaunchesListener#launchesChanged(org.eclipse.debug.core.ILaunch)
	 */
	public void launchChanged(ILaunch launch) {
	}

	private void update(ILaunch launch, boolean remove) {
		if (managedLaunches.contains(launch)) {
			if (remove || launch.isTerminated()) {
				managedLaunches.remove(launch);
				if (managedLaunches.size() == 0) {
					hookListener(false);
				}
			}
		}
	}

	private void hookListener(boolean add) {
		DebugPlugin debugPlugin = DebugPlugin.getDefault();
		ILaunchManager launchManager = debugPlugin.getLaunchManager();
		if (add) {
			launchManager.addLaunchListener(this);
			debugPlugin.addDebugEventListener(this);
		} else {
			launchManager.removeLaunchListener(this);
			debugPlugin.removeDebugEventListener(this);
		}
	}

	private void doRestart(ILaunch launch) {
		ILaunchConfiguration config = launch.getLaunchConfiguration();
		try {
			ILaunchConfigurationWorkingCopy copy = config.getWorkingCopy();
			copy.setAttribute(IPDEUIConstants.RESTART, true);
			copy.launch(launch.getLaunchMode(), new NullProgressMonitor());
		} catch (CoreException e) {
			PDEPlugin.logException(e);
		}
	}

	public void shutdown() {
		hookListener(false);
	}

	/**
	 * @see org.eclipse.debug.core.IDebugEventSetListener#handleDebugEvents(org.eclipse.debug.core.DebugEvent)
	 */
	public void handleDebugEvents(DebugEvent[] events) {
		for (int i = 0; i < events.length; i++) {
			DebugEvent event = events[i];
			Object source = event.getSource();
			if (source instanceof IProcess && event.getKind() == DebugEvent.TERMINATE) {
				IProcess process = (IProcess) source;
				ILaunch launch = process.getLaunch();
				if (launch != null) {
					try {
						launchTerminated(launch, process.getExitValue());
					} catch (DebugException e) {
					}
				}
			}
		}
	}

	private void launchTerminated(final ILaunch launch, int returnValue) {
		if (managedLaunches.contains(launch)) {
			update(launch, true);
			if (returnValue == 23) {
				doRestart(launch);
				return;
			}
			// launch failed because the associated workspace is in use
			if (returnValue == 15) {
				Display.getDefault().asyncExec(new Runnable() {
					public void run() {
						MessageDialog.openError(PDEPlugin.getActiveWorkbenchShell(), PDEUIMessages.Launcher_error_title, PDEUIMessages.Launcher_error_code15);
					}
				});
				return;
			}
			// launch failed for reasons printed to the log.
			if (returnValue == 13) {
				Display.getDefault().asyncExec(new Runnable() {
					public void run() {
						try {
							File log = getMostRecentLogFile(launch.getLaunchConfiguration());
							if (log != null && log.exists()) {
								MessageDialog dialog = new MessageDialog(PDEPlugin.getActiveWorkbenchShell(), PDEUIMessages.Launcher_error_title, null, // accept the default window icon
										PDEUIMessages.Launcher_error_code13, MessageDialog.ERROR, new String[] {PDEUIMessages.Launcher_error_displayInLogView, PDEUIMessages.Launcher_error_displayInSystemEditor, IDialogConstants.NO_LABEL}, OPEN_IN_ERROR_LOG_VIEW);
								int dialog_value = dialog.open();
								if (dialog_value == OPEN_IN_ERROR_LOG_VIEW) {
									LogView errlog = (LogView) PDEPlugin.getActivePage().showView("org.eclipse.pde.runtime.LogView"); //$NON-NLS-1$
									errlog.handleImportPath(log.getAbsolutePath());
									errlog.sortByDateDescending();
								} else if (dialog_value == OPEN_IN_SYSTEM_EDITOR) {
									openInEditor(log);
								}
							}
						} catch (CoreException e) {
						}
					}
				});
			}
		}
	}

	private void openInEditor(File log) {
		IFileStore fileStore = EFS.getLocalFileSystem().getStore(new Path(log.getAbsolutePath()));
		if (!fileStore.fetchInfo().isDirectory() && fileStore.fetchInfo().exists()) {
			IWorkbenchWindow ww = PDEPlugin.getActiveWorkbenchWindow();
			IWorkbenchPage page = ww.getActivePage();
			try {
				IDE.openEditorOnFileStore(page, fileStore);
			} catch (PartInitException e) {
			}
		}
	}

	/**
	 * Returns latest log file for Launch Configuration.
	 * It's ".metadala/.log", file with most recent timestamp ending with ".log"
	 * in configuration location or null if none found.
	 *
	 * @returns log file or null
	 * @throws CoreException
	 * @since 3.4
	 */
	static File getMostRecentLogFile(ILaunchConfiguration configuration) throws CoreException {
		File latest = null;
		String workspace = LaunchArgumentsHelper.getWorkspaceLocation(configuration);
		if (workspace.length() > 0) {
			latest = new File(workspace, ".metadata/.log"); //$NON-NLS-1$
			if (!latest.exists())
				latest = null;
		}
		File configDir = LaunchConfigurationHelper.getConfigurationLocation(configuration);
		File[] children = configDir.listFiles();
		if (children != null) {
			for (int i = 0; i < children.length; i++) {
				if (!children[i].isDirectory() && children[i].getName().endsWith(".log")) { //$NON-NLS-1$
					if (latest == null || latest.lastModified() < children[i].lastModified())
						latest = children[i];
				}
			}
		}
		return latest;
	}

}