/*******************************************************************************
 * Copyright (c) 2001, 2004 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
 *     Jens Lukowski/Innoopract - initial renaming/restructuring
 *     
 *******************************************************************************/
package org.eclipse.wst.sse.core;

import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.IResource;
import org.eclipse.core.resources.IResourceChangeEvent;
import org.eclipse.core.resources.IResourceChangeListener;
import org.eclipse.core.resources.IResourceDelta;
import org.eclipse.core.resources.IResourceDeltaVisitor;
import org.eclipse.core.resources.IWorkspace;
import org.eclipse.core.resources.ResourcesPlugin;
import org.eclipse.core.resources.WorkspaceJob;
import org.eclipse.core.runtime.CoreException;
import org.eclipse.core.runtime.IPluginDescriptor;
import org.eclipse.core.runtime.IProgressMonitor;
import org.eclipse.core.runtime.IStatus;
import org.eclipse.core.runtime.NullProgressMonitor;
import org.eclipse.core.runtime.Platform;
import org.eclipse.core.runtime.Plugin;
import org.eclipse.core.runtime.Preferences;
import org.eclipse.core.runtime.Status;
import org.eclipse.core.runtime.jobs.Job;
import org.eclipse.wst.common.encoding.CommonEncodingPreferenceNames;
import org.eclipse.wst.sse.core.internal.Logger;
import org.eclipse.wst.sse.core.internal.builder.StructuredDocumentBuilder;
import org.eclipse.wst.sse.core.internal.modelhandler.ModelHandlerRegistry;
import org.eclipse.wst.sse.core.internal.nls.ResourceHandler;
import org.eclipse.wst.sse.core.preferences.CommonModelPreferenceNames;
import org.osgi.framework.Bundle;


/**
 * This model manager plugin helper is used to return the model manager
 * desired to be used for creating a new model manager, for managing (add or
 * remove) model loaders and model dumpers, and for managing (get, release,
 * save, and save as) models. Here is an example on on how to use it. Under
 * the subdirectory named after your package which contains your
 * implementation of the model manager (e.g. "org.eclipse.wst.sse.core") in
 * the "project_resources\plugins" directory, create a "plugin.xml" file. In
 * this file ("projectproject_resources\plugins\com.ibm.sed.model\plugin.xml")
 * enter: <?xml version="1.0"?> <plugin name="IBM Web Tooling Model Manager
 * Plugin" id="org.eclipse.wst.sse.core" version="1.0" vendor-name="RTP"
 * class="org.eclipse.wst.sse.core.ModelManagerPlugin"> <!-- The XML package:
 * com.ibm.etools.b2bxmlrt, is required before the others to give precedence
 * to DOM2 APIs, instead of the DOM1 (used by others, such as the desktop
 * ("com.ibm.eclipse.*")) --> <requires><import
 * plugin="com.ibm.etools.b2bxmlrt" export="true"/> <import
 * plugin="org.eclipse.wst.common.contentmodel" export="true"/> </requires>
 * <runtime><library name="runtime/sedmodel.jar"> <export name="*"/>
 * </library> </runtime> </plugin> to tell the workbench the model manager
 * plugin ID and where to find this model manager plugin class. Then in the
 * getModelManager method of this model manager plugin class, create and
 * return the model manager desired to be used. In the client code that
 * requests the model manager, the following code should be used to access the
 * model manager via the plugin: // get the model manager from the plugin
 * ModelManagerPlugin plugin = (ModelManagerPlugin)
 * Platform.getPlugin(ModelManagerPlugin.ID); fModelManager =
 * plugin.getModelManager(); Note that the
 * wb.getPluginRegistry().getPluginDescriptor() method expects the plugin ID
 * as a parameter ("org.eclipse.wst.sse.core" in the above example).
 */
public class ModelPlugin extends Plugin implements IModelManagerPlugin {
	protected static class ProjectChangeListener implements IResourceChangeListener, IResourceDeltaVisitor {
		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.core.resources.IResourceChangeListener#resourceChanged(org.eclipse.core.resources.IResourceChangeEvent)
		 */
		public void resourceChanged(IResourceChangeEvent event) {
			IResourceDelta delta = event.getDelta();
			if (delta.getResource() != null) {
				int resourceType = delta.getResource().getType();
				if (resourceType == IResource.PROJECT || resourceType == IResource.ROOT) {
					try {
						delta.accept(this);
					} catch (CoreException e) {
						Logger.logException("Exception managing buildspec list", e); //$NON-NLS-1$
					}
				}
			}
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see org.eclipse.core.resources.IResourceDeltaVisitor#visit(org.eclipse.core.resources.IResourceDelta)
		 */
		public boolean visit(IResourceDelta delta) throws CoreException {
			IResource resource = delta.getResource();
			if (resource != null) {
				if (resource.getType() == IResource.ROOT)
					return true;
				else if (resource.getType() == IResource.PROJECT) {
					if (delta.getKind() == IResourceDelta.ADDED) {
						if (_debugResourceChangeListener) {
							System.out.println("Project " + delta.getResource().getName() + " added to workspace and registering with SDMB");//$NON-NLS-2$//$NON-NLS-1$
						}
						StructuredDocumentBuilder.add(new NullProgressMonitor(), (IProject) resource, null);
					}
					return false;
				}
			}
			return false;
		}
	}

	static final boolean _debugResourceChangeListener = "true".equalsIgnoreCase(Platform.getDebugOption("org.eclipse.wst.sse.core/resourcechangehandling")); //$NON-NLS-1$ //$NON-NLS-2$
	static ModelPlugin instance = null;
	private static final String OFF = "off"; //$NON-NLS-1$

	public static final String STRUCTURED_BUILDER = "org.eclipse.wst.sse.core.structuredbuilder"; //$NON-NLS-1$

	public static ModelPlugin getDefault() {
		return instance;
	}

	public static String getID() {
		return getDefault().getBundle().getSymbolicName();
	}

	private ProjectChangeListener changeListener;

	public ModelPlugin() {
		super();
		instance = this;
	}

	public ModelPlugin(IPluginDescriptor descriptor) {
		super(descriptor);
		instance = this;

	}

	public ModelHandlerRegistry getModelHandlerRegistry() {
		return ModelHandlerRegistry.getInstance();
	}

	public IModelManager getModelManager() {
		boolean isReady = false;
		IModelManager modelManager = null;
		while (!isReady) {
			Bundle localBundle = getBundle();
			int state = localBundle.getState();
			if (state == Bundle.ACTIVE) {
				isReady = true;
				// getInstance is a synchronized static method.
				modelManager = ModelManagerImpl.getInstance();
			} else if (state == Bundle.STARTING) {
				try {
					Thread.sleep(100);
				} catch (InterruptedException e) {
					// ignore, just loop again
				}
			} else if (state == Bundle.STOPPING) {
				isReady = true;
				modelManager = new NullModelManager();
			} else if (state == Bundle.UNINSTALLED) {
				isReady = true;
				modelManager = new NullModelManager();
			} else {
				// not sure about other states, 'resolved', 'installed'
				isReady = true;
			}
		}
		return modelManager;
	}

	/**
	 * Set default non-UI
	 */
	protected void initializeDefaultPluginPreferences() {
		super.initializeDefaultPluginPreferences();
		Preferences prefs = getDefault().getPluginPreferences();
		// set model preference defaults
		prefs.setDefault(CommonModelPreferenceNames.CLEANUP_TAG_NAME_CASE, CommonModelPreferenceNames.ASIS);
		prefs.setDefault(CommonModelPreferenceNames.CLEANUP_ATTR_NAME_CASE, CommonModelPreferenceNames.ASIS);
		prefs.setDefault(CommonModelPreferenceNames.COMPRESS_EMPTY_ELEMENT_TAGS, true);
		prefs.setDefault(CommonModelPreferenceNames.INSERT_REQUIRED_ATTRS, true);
		prefs.setDefault(CommonModelPreferenceNames.INSERT_MISSING_TAGS, true);
		prefs.setDefault(CommonModelPreferenceNames.QUOTE_ATTR_VALUES, true);
		prefs.setDefault(CommonModelPreferenceNames.FORMAT_SOURCE, true);
		prefs.setDefault(CommonModelPreferenceNames.CONVERT_EOL_CODES, false);
		prefs.setDefault(CommonEncodingPreferenceNames.INPUT_CODESET, ""); //$NON-NLS-1$
		prefs.setDefault(CommonEncodingPreferenceNames.OUTPUT_CODESET, CommonModelPreferenceNames.UTF_8);
		prefs.setDefault(CommonEncodingPreferenceNames.END_OF_LINE_CODE, ""); //$NON-NLS-1$
		prefs.setDefault(CommonModelPreferenceNames.TAB_WIDTH, CommonModelPreferenceNames.DEFAULT_TAB_WIDTH);
		prefs.setDefault(CommonModelPreferenceNames.FORMATTING_SUPPORTED, false);
		prefs.setDefault(CommonModelPreferenceNames.LINE_WIDTH, 72);
		prefs.setDefault(CommonModelPreferenceNames.SPLIT_MULTI_ATTRS, false);
		prefs.setDefault(CommonModelPreferenceNames.INDENT_USING_TABS, true);
		prefs.setDefault(CommonModelPreferenceNames.CLEAR_ALL_BLANK_LINES, false);
		prefs.setDefault(CommonModelPreferenceNames.PREFERRED_MARKUP_CASE_SUPPORTED, false);
		prefs.setDefault(CommonModelPreferenceNames.TAG_NAME_CASE, CommonModelPreferenceNames.UPPER);
		prefs.setDefault(CommonModelPreferenceNames.ATTR_NAME_CASE, CommonModelPreferenceNames.LOWER);
		prefs.setDefault(CommonModelPreferenceNames.TASK_TAG_ENABLE, false);
		prefs.setDefault(CommonModelPreferenceNames.TASK_TAG_TAGS, "TODO,FIXME,XXX"); //$NON-NLS-1$
		prefs.setDefault(CommonModelPreferenceNames.TASK_TAG_PRIORITIES, "1,2,1"); //$NON-NLS-1$
	}

	public void shutdown() throws CoreException {
		super.shutdown();
		savePluginPreferences();
		// Remove the listener from the workspace
		IWorkspace workspace = ResourcesPlugin.getWorkspace();
		if (changeListener != null && workspace != null) {
			workspace.removeResourceChangeListener(changeListener);
		}
		FileBufferModelManager.shutdown();
	}

	/*
	 * (non-Javadoc)
	 * 
	 * @see org.eclipse.core.runtime.Plugin#startup()
	 */
	public void startup() throws CoreException {
		super.startup();

		String build = System.getProperty(STRUCTURED_BUILDER);
		if (build == null || !build.equalsIgnoreCase(OFF)) {
			// TODO: always off, until redesigned
			// doTaskTagProcessing();
		}
		// initialize FileBuffer handling
		FileBufferModelManager.startup();

	}

	// make private if ever used again
	 void doTaskTagProcessing() {
		// Must make sure the builder is registered for projects which may
		// have
		// been created before this plugin was activated.
		Job adder = new WorkspaceJob(ResourceHandler.getString("ModelPlugin.0")) { //$NON-NLS-1$
			public IStatus runInWorkspace(IProgressMonitor monitor) {
				StructuredDocumentBuilder.add(monitor, ResourcesPlugin.getWorkspace().getRoot(), null);
				return Status.OK_STATUS;
			}
		};
		adder.setSystem(true);
		// use SHORT, since once executing,
		// this job should be quick, since
		// this is the job that just adds
		// to the .project files. Its later
		// that files are scanned for task
		// tags.
		adder.setPriority(Job.SHORT);
		// since we have potential to change several .project files,
		// we should wait until we can get exclusive access to
		// whole workspace.
		// TODO: future re-design should not require this.
		adder.setRule(ResourcesPlugin.getWorkspace().getRoot());
		adder.schedule();

		// Register the ProjectChangeListener so that it can add the
		// builder
		// to projects as needed
		changeListener = new ProjectChangeListener();
		ResourcesPlugin.getWorkspace().addResourceChangeListener(changeListener, IResourceChangeEvent.PRE_BUILD);
	}
}