/*******************************************************************************
 * Copyright (c) 2000, 2004 IBM Corporation and others.
 * All rights reserved. This program and the accompanying materials 
 * are made available under the terms of the Common Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/cpl-v10.html
 * 
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.debug.internal.ui.views.console;


import java.text.MessageFormat;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExtensionPoint;
import org.eclipse.core.runtime.Platform;
import org.eclipse.debug.core.DebugPlugin;
import org.eclipse.debug.core.ILaunch;
import org.eclipse.debug.core.ILaunchListener;
import org.eclipse.debug.core.ILaunchManager;
import org.eclipse.debug.core.model.IProcess;
import org.eclipse.debug.internal.ui.DebugUIPlugin;
import org.eclipse.debug.internal.ui.preferences.IDebugPreferenceConstants;
import org.eclipse.debug.ui.IDebugUIConstants;
import org.eclipse.debug.ui.console.ConsoleColorProvider;
import org.eclipse.debug.ui.console.IConsoleColorProvider;
import org.eclipse.debug.ui.console.IConsoleLineTracker;
import org.eclipse.jface.text.IDocument;
import org.eclipse.ui.console.ConsolePlugin;
import org.eclipse.ui.console.IConsole;
import org.eclipse.ui.console.IConsoleManager;

/**
 * Creates documents for processes as they are registered with a launch.
 * The singleton manager is accessible from the debug UI plugin.
 */
public class ProcessConsoleManager implements ILaunchListener {
	
	/**
	 * Console document content provider extensions, keyed by extension id
	 */
	private Map fColorProviders;
	
	/**
	 * The default color provider. Used if no color provider is contributed
	 * for the given process type.
	 */
	private IConsoleColorProvider fDefaultColorProvider;
	
	/**
	 * Console line trackers; keyed by process type to list of trackers (1:N) 
	 */
	private Map fLineTrackers;
	
	/**
	 * Map of processes for a launch to compute removed processes
	 */
	private Map fProcesses;

    
	/**
	 * @see ILaunchListener#launchRemoved(ILaunch)
	 */
	public void launchRemoved(ILaunch launch) {
		removeLaunch(launch);
	}
	
	protected void removeLaunch(ILaunch launch) {
		IProcess[] processes= launch.getProcesses(); 
		for (int i= 0; i < processes.length; i++) {
			IProcess iProcess = processes[i];
			removeProcess(iProcess);
		}		
		if (fProcesses != null) {
			fProcesses.remove(launch);
		}
	}
	
	/**
	 * Removes the console and document associated with the given process.
	 * 
	 * @param iProcess process to clean up
	 */
	private void removeProcess(IProcess iProcess) {
		IConsole console = getConsole(iProcess);
		
		if (console != null) {
			IConsoleManager manager = ConsolePlugin.getDefault().getConsoleManager();
			manager.removeConsoles(new IConsole[]{console});
		}
	}

	/**
	 * Returns the console for the given process, or <code>null</code> if none.
	 * 
	 * @param process
	 * @return the console for the given process, or <code>null</code> if none
	 */
	public IConsole getConsole(IProcess process) {
		IConsoleManager manager = ConsolePlugin.getDefault().getConsoleManager(); 
		IConsole[] consoles = manager.getConsoles();
		for (int i = 0; i < consoles.length; i++) {
			IConsole console = consoles[i];
			if (console instanceof ProcessConsole) {
				ProcessConsole pc = (ProcessConsole)console;
				if (pc.getProcess().equals(process)) {
					return pc;
				}
			}
		}
		return null;
	}

	/**
	 * @see ILaunchListener#launchAdded(ILaunch)
	 */
	public void launchAdded(ILaunch launch) {
		launchChanged(launch);
	}

	/**
	 * @see ILaunchListener#launchChanged(ILaunch)
	 */
	public void launchChanged(final ILaunch launch) {
		DebugUIPlugin.getStandardDisplay().syncExec(new Runnable () {
			public void run() {
				IProcess[] processes= launch.getProcesses();
				for (int i= 0; i < processes.length; i++) {
					if (getConsoleDocument(processes[i]) == null) {
						IProcess process = processes[i];
						if (process.getStreamsProxy() == null) {
							continue;
						}
						//create a new console.
						IConsoleColorProvider colorProvider = getColorProvider(process.getAttribute(IProcess.ATTR_PROCESS_TYPE));
						ProcessConsole pc = new ProcessConsole(process, colorProvider);
						pc.setAttribute(IDebugUIConstants.ATTR_CONSOLE_PROCESS, process);
						//add new console to console manager.
						ConsolePlugin.getDefault().getConsoleManager().addConsoles(new IConsole[]{pc});
					}
				}
				List removed = getRemovedProcesses(launch);
				if (removed != null) {
					Iterator iterator = removed.iterator();
					while (iterator.hasNext()) {
						IProcess p = (IProcess) iterator.next();
						removeProcess(p);
					}
				}
			}
		});
	}
	
	/**
	 * Returns the document for the process, or <code>null</code>
	 * if none.
	 */
	public IDocument getConsoleDocument(IProcess process) {
	    ProcessConsole console = (ProcessConsole) getConsole(process);
	    return (console != null ? console.getDocument() : null);
	} 
		
	/**
	 * Called by the debug ui plug-in on startup.
	 * The console document manager starts listening for
	 * launches to be registered and initializes if any launches
	 * already exist.
	 */
	public void startup() {
		ILaunchManager launchManager= DebugPlugin.getDefault().getLaunchManager();
		launchManager.addLaunchListener(this);	

		//set up the docs for launches already registered
		ILaunch[] launches= launchManager.getLaunches();
		for (int i = 0; i < launches.length; i++) {
			launchAdded(launches[i]);
		}
	}
	
	/**
	 * Called by the debug ui plug-in on shutdown.
	 * The console document manager de-registers as a 
	 * launch listener and kills all existing console documents.
	 */
	public void shutdown() {
		ILaunchManager launchManager= DebugPlugin.getDefault().getLaunchManager();
		ILaunch[] launches = launchManager.getLaunches();
		for (int i = 0; i < launches.length; i++) {
			ILaunch launch = launches[i];
			removeLaunch(launch);
		}
		launchManager.removeLaunchListener(this);
		if (fProcesses != null) {
			fProcesses.clear();
		}
	}
	
	/**
	 * Notifies the console document manager that system err is about to be written
	 * to the console. The manager will open the console if the preference is
	 * set to show the console on system err.
	 */
	protected void aboutToWriteSystemErr(IProcess process) {
		if (DebugUIPlugin.getDefault().getPreferenceStore().getBoolean(IDebugPreferenceConstants.CONSOLE_OPEN_ON_ERR)) {
			showConsole(process);
		}
	}
	
	/**
	 * Notifies the console document manager that system out is about to be written
	 * to the console. The manager will open the console if the preference is
	 * set to show the console on system out and the console document being written 
	 * is associated with the current process.
	 */	
	protected void aboutToWriteSystemOut(IProcess process) {
		if (DebugUIPlugin.getDefault().getPreferenceStore().getBoolean(IDebugPreferenceConstants.CONSOLE_OPEN_ON_OUT)) {
			showConsole(process);
		}
	}
	
	/**
	 * Opens the console view. If the view is already open, it is brought to the front.
	 */
	protected void showConsole(final IProcess process) {
		ConsolePlugin.getDefault().getConsoleManager().showConsoleView(getConsole(process));
	}
	
	/**
	 * Returns a new console document color provider extension for the given
	 * process type, or <code>null</code> if none.
	 * 
	 * @param type corresponds to <code>IProcess.ATTR_PROCESS_TYPE</code>
	 * @return IConsoleColorProvider
	 */
	public IConsoleColorProvider getColorProvider(String type) {
		if (fColorProviders == null) {
			fColorProviders = new HashMap();
			IExtensionPoint extensionPoint= Platform.getExtensionRegistry().getExtensionPoint(DebugUIPlugin.getUniqueIdentifier(), IDebugUIConstants.EXTENSION_POINT_CONSOLE_COLOR_PROVIDERS);
			IConfigurationElement[] elements = extensionPoint.getConfigurationElements();
			for (int i = 0; i < elements.length; i++) {
				IConfigurationElement extension = elements[i];
				fColorProviders.put(extension.getAttributeAsIs("processType"), extension); //$NON-NLS-1$
			}
		}
		IConfigurationElement extension = (IConfigurationElement)fColorProviders.get(type);
		if (extension != null) {
			try {
				Object colorProvider = extension.createExecutableExtension("class"); //$NON-NLS-1$
				if (colorProvider instanceof IConsoleColorProvider) {
					return (IConsoleColorProvider)colorProvider;
				} 
				DebugUIPlugin.logErrorMessage(MessageFormat.format(ConsoleMessages.getString("ConsoleDocumentManager.1"),new String[]{extension.getDeclaringExtension().getUniqueIdentifier()} )); //$NON-NLS-1$
			} catch (CoreException e) {
				DebugUIPlugin.log(e);
			}
		}
		//no color provider found of specified type, return default color provider.
		if (fDefaultColorProvider == null) {
		    fDefaultColorProvider = new ConsoleColorProvider();
		}
		return fDefaultColorProvider;
	} 
	
	/**
	 * Returns the Line Trackers for a given process type.
	 * @param process The process for which line trackers are required.
	 * @return An array of line trackers which match the given process type.
	 */
	public IConsoleLineTracker[] getLineTrackers(IProcess process) {
		String type = process.getAttribute(IProcess.ATTR_PROCESS_TYPE);

		if (fLineTrackers == null) {
			fLineTrackers = new HashMap();
			IExtensionPoint extensionPoint= Platform.getExtensionRegistry().getExtensionPoint(DebugUIPlugin.getUniqueIdentifier(), IDebugUIConstants.EXTENSION_POINT_CONSOLE_LINE_TRACKERS);
			IConfigurationElement[] elements = extensionPoint.getConfigurationElements();
			for (int i = 0; i < elements.length; i++) {
				IConfigurationElement extension = elements[i];
				String processType = extension.getAttributeAsIs("processType"); //$NON-NLS-1$
				List list = (List)fLineTrackers.get(processType);
				if (list == null) {
					list = new ArrayList();
					fLineTrackers.put(processType, list);
				}
				list.add(extension);
			}
		}
		
		ArrayList trackers = new ArrayList();
		if (type != null) {
		    List lineTrackerExtensions = (List) fLineTrackers.get(type);
		    if(lineTrackerExtensions != null) {   
		        for(Iterator i = lineTrackerExtensions.iterator(); i.hasNext(); ) {
		            IConfigurationElement element = (IConfigurationElement) i.next();
		            try {
		                trackers.add(element.createExecutableExtension("class")); //$NON-NLS-1$
		            } catch (CoreException e) {
		                DebugUIPlugin.log(e);
		            }
		        }
		    }
		}
		return (IConsoleLineTracker[]) trackers.toArray(new IConsoleLineTracker[0]);
	}
	
	/**
	 * Returns the processes that have been removed from the given
	 * launch, or <code>null</code> if none.
	 * 
	 * @param launch launch that has changed
	 * @return removed processes or <code>null</code>
	 */
	private List getRemovedProcesses(ILaunch launch) {
		List removed = null;
		if (fProcesses == null) {
			fProcesses = new HashMap();
		}
		IProcess[] old = (IProcess[]) fProcesses.get(launch);
		IProcess[] curr = launch.getProcesses();
		if (old != null) {
			for (int i = 0; i < old.length; i++) {
				IProcess process = old[i];
				if (!contains(curr, process)) {
					if (removed == null) {
						removed = new ArrayList();
					}
					removed.add(process);
				}
			}
		}
		// update cache with current processes
		fProcesses.put(launch, curr);
		return removed;
	}
	
	/**
	 * Returns whether the given object is contained in the list.
	 * 
	 * @param list list to search
	 * @param object object to search for
	 * @return whether the given object is contained in the list
	 */
	private boolean contains(Object[] list, Object object) {
		for (int i = 0; i < list.length; i++) {
			Object object2 = list[i];
			if (object2.equals(object)) {
				return true;
			}
		}
		return false;
	}
}