/*******************************************************************************
 * Copyright (c) 2000, 2003 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.ui.internal.commands;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.StringTokenizer;

import org.eclipse.core.runtime.IConfigurationElement;
import org.eclipse.core.runtime.IExtension;
import org.eclipse.core.runtime.IPluginDescriptor;
import org.eclipse.core.runtime.IPluginRegistry;
import org.eclipse.core.runtime.Platform;
import org.eclipse.ui.PlatformUI;

public final class CoreRegistry extends AbstractRegistry {

	private final class RegistryReader extends org.eclipse.ui.internal.registry.RegistryReader {

		private final static String DEPRECATED_KEY_SEQUENCE_SEPARATOR = "||"; //$NON-NLS-1$
		private final static String DEPRECATED_TAG_ACCELERATOR = "accelerator"; //$NON-NLS-1$	
		private final static String DEPRECATED_TAG_ACCELERATOR_CONFIGURATION = "acceleratorConfiguration"; //$NON-NLS-1$
		private final static String DEPRECATED_TAG_ACCELERATOR_CONFIGURATIONS = "acceleratorConfigurations"; //$NON-NLS-1$		
		private final static String DEPRECATED_TAG_ACCELERATOR_SCOPE = "acceleratorScope"; //$NON-NLS-1$
		private final static String DEPRECATED_TAG_ACCELERATOR_SCOPES = "acceleratorScopes"; //$NON-NLS-1$		
		private final static String DEPRECATED_TAG_ACCELERATOR_SET = "acceleratorSet"; //$NON-NLS-1$
		private final static String DEPRECATED_TAG_ACCELERATOR_SETS = "acceleratorSets"; //$NON-NLS-1$
		private final static String DEPRECATED_TAG_ACTION_DEFINITION = "actionDefinition"; //$NON-NLS-1$
		private final static String DEPRECATED_TAG_ACTION_DEFINITIONS = "actionDefinitions"; //$NON-NLS-1$
		private final static String DEPRECATED_TAG_CONFIGURATION_ID = "configurationId"; //$NON-NLS-1$		
		private final static String DEPRECATED_TAG_KEY = "key"; //$NON-NLS-1$
		private final static String DEPRECATED_TAG_SCOPE_ID = "scopeId"; //$NON-NLS-1$	
		private final static int RANK_CORE = 2;
		private final static String TAG_ROOT = Persistence.PACKAGE_BASE;
		
		private List activeGestureConfigurations;
		private List activeKeyConfigurations;		
		private List categories;
		private List commands;
		private List gestureBindings;
		private List gestureConfigurations;
		private List keyBindings;
		private String keyConfiguration;
		private List keyConfigurations;
		private String scope;
		private List scopes;
	
		private RegistryReader(IPluginRegistry pluginRegistry) {
			super();
			activeGestureConfigurations = new ArrayList();
			activeKeyConfigurations = new ArrayList();		
			categories = new ArrayList();
			commands = new ArrayList();
			gestureBindings = new ArrayList();
			gestureConfigurations = new ArrayList();
			keyBindings = new ArrayList();
			keyConfigurations = new ArrayList();
			scopes = new ArrayList();

			if (pluginRegistry != null) {
				readRegistry(pluginRegistry, PlatformUI.PLUGIN_ID, DEPRECATED_TAG_ACCELERATOR_CONFIGURATIONS);
				readRegistry(pluginRegistry, PlatformUI.PLUGIN_ID, DEPRECATED_TAG_ACCELERATOR_SCOPES);
				readRegistry(pluginRegistry, PlatformUI.PLUGIN_ID, DEPRECATED_TAG_ACCELERATOR_SETS);
				readRegistry(pluginRegistry, PlatformUI.PLUGIN_ID, DEPRECATED_TAG_ACTION_DEFINITIONS);				
				readRegistry(pluginRegistry, PlatformUI.PLUGIN_ID, TAG_ROOT);
			}

			CoreRegistry.this.activeGestureConfigurations = Collections.unmodifiableList(activeGestureConfigurations);
			CoreRegistry.this.activeKeyConfigurations = Collections.unmodifiableList(activeKeyConfigurations);
			CoreRegistry.this.categories = Collections.unmodifiableList(categories);
			CoreRegistry.this.commands = Collections.unmodifiableList(commands);
			CoreRegistry.this.gestureBindings = Collections.unmodifiableList(gestureBindings);
			CoreRegistry.this.gestureConfigurations = Collections.unmodifiableList(gestureConfigurations);
			CoreRegistry.this.keyBindings = Collections.unmodifiableList(keyBindings);
			CoreRegistry.this.keyConfigurations = Collections.unmodifiableList(keyConfigurations);
			CoreRegistry.this.scopes = Collections.unmodifiableList(scopes);
		}

		protected boolean readElement(IConfigurationElement element) {
			String name = element.getName();

			if (DEPRECATED_TAG_ACCELERATOR.equals(name) || DEPRECATED_TAG_ACCELERATOR_SET.equals(name)) {
				/*
				logError(element, 
					"'" + TAG_ACCELERATOR + //$NON-NLS-1$
					"', '" + TAG_ACCELERATOR_SET + //$NON-NLS-1$
					"' and '" + TAG_ACCELERATOR_SETS + //$NON-NLS-1$ 
					"' have been deprecated. please replace them with '" + Persistence.TAG_REGIONAL_KEY_BINDING + //$NON-NLS-1$ 
					"' and '" + Persistence.TAG_REGIONAL_KEY_BINDINGS + //$NON-NLS-1$
					"' in all places."); //$NON-NLS-1$
				*/
				
				if (DEPRECATED_TAG_ACCELERATOR.equals(name))
					return readDeprecatedAccelerator(element);
				else 
					return readDeprecatedAcceleratorSet(element);
			} 

			if (DEPRECATED_TAG_ACCELERATOR_CONFIGURATION.equals(name)) {
				/*
				logError(element, 
					"'" + TAG_ACCELERATOR_CONFIGURATION + //$NON-NLS-1$
					"' and '" + TAG_ACCELERATOR_CONFIGURATIONS + //$NON-NLS-1$ 
					"' have been deprecated. please replace them with '" + Persistence.TAG_KEY_CONFIGURATION + //$NON-NLS-1$ 
					"' and '" + Persistence.TAG_KEY_CONFIGURATIONS + //$NON-NLS-1$
					"' in all places."); //$NON-NLS-1$
				*/
				return readKeyConfiguration(element);
			}

			if (DEPRECATED_TAG_ACCELERATOR_SCOPE.equals(name)) {
				/*
				logError(element, 
					"'" + TAG_ACCELERATOR_SCOPE + //$NON-NLS-1$
					"' and '" + TAG_ACCELERATOR_SCOPES + //$NON-NLS-1$ 
					"' have been deprecated. please replace them with '" + Persistence.TAG_SCOPE + //$NON-NLS-1$ 
					"' and '" + Persistence.TAG_SCOPES + //$NON-NLS-1$
					"' in all places."); //$NON-NLS-1$
				*/
				return readScope(element);
			}

			if (DEPRECATED_TAG_ACTION_DEFINITION.equals(name)) {
				/*
				logError(element, 
					"'" + TAG_ACTION_DEFINITION + //$NON-NLS-1$
					"' and '" + TAG_ACTION_DEFINITIONS + //$NON-NLS-1$ 
					"' have been deprecated. please replace them with '" + Persistence.TAG_COMMAND + //$NON-NLS-1$ 
					"' and '" + Persistence.TAG_COMMANDS + //$NON-NLS-1$
					"' in all places."); //$NON-NLS-1$
				*/
				return readCommand(element);
			}

			if (Persistence.TAG_ACTIVE_GESTURE_CONFIGURATION.equals(name))
				return readActiveGestureConfiguration(element);

			if (Persistence.TAG_ACTIVE_KEY_CONFIGURATION.equals(name))
				return readActiveKeyConfiguration(element);

			if (Persistence.TAG_CATEGORY.equals(name))
				return readCategory(element);

			if (Persistence.TAG_COMMAND.equals(name))
				return readCommand(element);

			if (Persistence.TAG_GESTURE_BINDING.equals(name))
				return readGestureBinding(element);

			if (Persistence.TAG_GESTURE_CONFIGURATION.equals(name))
				return readGestureConfiguration(element);

			if (Persistence.TAG_KEY_BINDING.equals(name))
				return readKeyBinding(element);

			if (Persistence.TAG_KEY_CONFIGURATION.equals(name))
				return readKeyConfiguration(element);

			if (Persistence.TAG_SCOPE.equals(name))
				return readScope(element);
	
			return false;
		}

		private String getPlugin(IConfigurationElement element) {
			String plugin = null;	
		
			if (element != null) {	
				IExtension extension = element.getDeclaringExtension();
			
				if (extension != null) {
					IPluginDescriptor pluginDescriptor = extension.getDeclaringPluginDescriptor();
				
					if (pluginDescriptor != null) 
						plugin = pluginDescriptor.getUniqueIdentifier();				
				}
			}

			return plugin;
		}

		private boolean readActiveGestureConfiguration(IConfigurationElement element) {
			ActiveConfiguration activeGestureConfiguration = Persistence.readActiveConfiguration(ConfigurationElementMemento.create(element), getPlugin(element));
		
			if (activeGestureConfiguration != null)
				activeGestureConfigurations.add(activeGestureConfiguration);	
			
			return true;
		}

		private boolean readActiveKeyConfiguration(IConfigurationElement element) {
			ActiveConfiguration activeKeyConfiguration = Persistence.readActiveConfiguration(ConfigurationElementMemento.create(element), getPlugin(element));
		
			if (activeKeyConfiguration != null)
				activeKeyConfigurations.add(activeKeyConfiguration);	
			
			return true;
		}

		private boolean readCategory(IConfigurationElement element) {
			Category category = Persistence.readCategory(ConfigurationElementMemento.create(element), getPlugin(element));
		
			if (category != null)
				categories.add(category);	
			
			return true;
		}

		private boolean readCommand(IConfigurationElement element) {
			Command command = Persistence.readCommand(ConfigurationElementMemento.create(element), getPlugin(element));
		
			if (command != null)
				commands.add(command);	
			
			return true;
		}

		private boolean readDeprecatedAccelerator(IConfigurationElement element) {
			if (keyConfiguration == null || scope == null)
				return false;

			String id = element.getAttribute(Persistence.TAG_ID);
			String key = element.getAttribute(DEPRECATED_TAG_KEY);

			if (key != null) {
				List sequences = new ArrayList();	
				StringTokenizer orTokenizer = new StringTokenizer(key, DEPRECATED_KEY_SEQUENCE_SEPARATOR); 
			
				while (orTokenizer.hasMoreTokens()) {					
					try {			
						Sequence sequence = KeySupport.parseSequence(orTokenizer.nextToken());

						if (sequence.getStrokes().size() >= 1)
							sequences.add(sequence);		
					} catch (IllegalArgumentException eIllegalArgument) {					
					}
				}		
				
				if (sequences.size() >= 1) {
					String locale = element.getAttribute(Persistence.TAG_LOCALE);
		
					if (locale == null)
						locale = Util.ZERO_LENGTH_STRING;
		
					String platform = element.getAttribute(Persistence.TAG_PLATFORM);
		
					if (platform == null)
						platform = Util.ZERO_LENGTH_STRING;
		
					String plugin = getPlugin(element);				
					Iterator iterator = sequences.iterator();
				
					while (iterator.hasNext()) {
						Sequence sequence = (Sequence) iterator.next();			
						keyBindings.add(SequenceBinding.create(keyConfiguration, id, locale, platform, plugin, RANK_CORE, scope, sequence));	
					}
				}
			}

			return true;
		}

		private boolean readDeprecatedAcceleratorSet(IConfigurationElement element) {
			keyConfiguration = element.getAttribute(DEPRECATED_TAG_CONFIGURATION_ID);
			scope = element.getAttribute(DEPRECATED_TAG_SCOPE_ID);
			
			if (keyConfiguration != null && scope != null)
				readElementChildren(element);
				
			keyConfiguration = null;
			scope = null;
			return true;
		}	

		private boolean readGestureBinding(IConfigurationElement element) {
			SequenceBinding gestureBinding = Persistence.readBinding(ConfigurationElementMemento.create(element), getPlugin(element), RANK_CORE);

			if (gestureBinding != null)
				gestureBindings.add(gestureBinding);

			return true;
		}

		private boolean readGestureConfiguration(IConfigurationElement element) {
			Configuration gestureConfiguration = Persistence.readConfiguration(ConfigurationElementMemento.create(element), getPlugin(element));
		
			if (gestureConfiguration != null)
				gestureConfigurations.add(gestureConfiguration);	
			
			return true;
		}

		private boolean readKeyBinding(IConfigurationElement element) {
			SequenceBinding keyBinding = Persistence.readBinding(ConfigurationElementMemento.create(element), getPlugin(element), RANK_CORE);

			if (keyBinding != null)
				keyBindings.add(keyBinding);

			return true;
		}
	
		private boolean readKeyConfiguration(IConfigurationElement element) {
			Configuration keyConfiguration = Persistence.readConfiguration(ConfigurationElementMemento.create(element), getPlugin(element));
		
			if (keyConfiguration != null)
				keyConfigurations.add(keyConfiguration);	
			
			return true;
		}

		private boolean readScope(IConfigurationElement element) {
			Scope scope = Persistence.readScope(ConfigurationElementMemento.create(element), getPlugin(element));
		
			if (scope != null)
				scopes.add(scope);	
			
			return true;
		}
	}

	private static CoreRegistry instance;
	
	public static CoreRegistry getInstance() {
		if (instance == null)
			instance = new CoreRegistry();
	
		return instance;
	}

	private boolean loaded;

	private CoreRegistry() {
		super();
	}

	public void load()
		throws IOException {		
		if (!loaded) {
			new RegistryReader(Platform.getPluginRegistry());
			loaded = true;
		}
	}
}