/*******************************************************************************
 * 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.cdt.internal.ui.viewsupport;

import java.io.IOException;
import java.io.Reader;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.HashSet;
import java.util.Set;

import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.ProjectScope;
import org.eclipse.core.runtime.Assert;
import org.eclipse.jface.text.templates.Template;
import org.eclipse.jface.text.templates.persistence.TemplatePersistenceData;
import org.eclipse.jface.text.templates.persistence.TemplateReaderWriter;
import org.eclipse.jface.text.templates.persistence.TemplateStore;
import org.eclipse.ui.preferences.ScopedPreferenceStore;

import org.eclipse.cdt.ui.CUIPlugin;

/**
 * @since 5.0
 */
public final class ProjectTemplateStore {
	
	private static final String KEY= "org.eclipse.cdt.ui.text.custom_code_templates"; //$NON-NLS-1$

	private final TemplateStore fInstanceStore;
	private final TemplateStore fProjectStore;
	
	public ProjectTemplateStore(IProject project) {
		fInstanceStore= CUIPlugin.getDefault().getCodeTemplateStore();
		if (project == null) {
			fProjectStore= null;
		} else {
			final ScopedPreferenceStore projectSettings= new ScopedPreferenceStore(new ProjectScope(project), CUIPlugin.PLUGIN_ID);
			fProjectStore= new TemplateStore(projectSettings, KEY) {
				/*
				 * Make sure we keep the id of added code templates - add removes
				 * it in the usual add() method
				 */
				@Override
				public void add(TemplatePersistenceData data) {
					if (data.isUserAdded()) {
						super.add(data);
					} else {
						internalAdd(data);
					}
				}
				
				@Override
				public void save() throws IOException {
					
					StringWriter output= new StringWriter();
					TemplateReaderWriter writer= new TemplateReaderWriter();
					writer.save(getTemplateData(false), output);
					
					projectSettings.setValue(KEY, output.toString());
					projectSettings.save();
				}
			};
		}
	}
	
	public static boolean hasProjectSpecificTempates(IProject project) {
		String pref= new ProjectScope(project).getNode(CUIPlugin.PLUGIN_ID).get(KEY, null);
		if (pref != null && pref.trim().length() > 0) {
			Reader input= new StringReader(pref);
			TemplateReaderWriter reader= new TemplateReaderWriter();
			TemplatePersistenceData[] datas;
			try {
				datas= reader.read(input);
				return datas.length > 0;
			} catch (IOException e) {
				// ignore
			}
		}
		return false;
	}
	
	
	public TemplatePersistenceData[] getTemplateData() {
		if (fProjectStore != null) {
			return fProjectStore.getTemplateData(true);
		}
		return fInstanceStore.getTemplateData(true);
	}
	
	public Template findTemplateById(String id) {
		Template template= null;
		if (fProjectStore != null)
			template= fProjectStore.findTemplateById(id);
		if (template == null)
			template= fInstanceStore.findTemplateById(id);
		
		return template;
	}
	
	public void load() throws IOException {
		if (fProjectStore != null) {
			fProjectStore.load();
			
			Set<String> datas= new HashSet<String>();
			TemplatePersistenceData[] data= fProjectStore.getTemplateData(false);
			for (TemplatePersistenceData element : data) {
				String id= element.getId();
				if (id == null) {
					id= element.getTemplate().getName();
				}
				datas.add(id);
			}
			
			data= fInstanceStore.getTemplateData(false);
			for (TemplatePersistenceData orig : data) {
				String origId= orig.getId();
				if (origId == null) {
					origId= orig.getTemplate().getName();
				}
				if (!datas.contains(orig.getId())) {
					TemplatePersistenceData copy= new TemplatePersistenceData(new Template(orig.getTemplate()), orig.isEnabled(), orig.getId());
					fProjectStore.add(copy);
					copy.setDeleted(true);
				}
			}
		}
	}
	
	public boolean isProjectSpecific(String id) {
		if (id == null) {
			return false;
		}
		
		if (fProjectStore == null)
			return false;
		
		return fProjectStore.findTemplateById(id) != null;
	}
	
	
	public void setProjectSpecific(String id, boolean projectSpecific) {
		Assert.isNotNull(fProjectStore);
		
		TemplatePersistenceData data= fProjectStore.getTemplateData(id);
		if (data == null) {
			return; // does not exist
		}
		data.setDeleted(!projectSpecific);
	}

	public void restoreDefaults() {
		if (fProjectStore == null) {
			fInstanceStore.restoreDefaults();
		} else {
			fProjectStore.restoreDefaults();
		}
	}
	
	public void save() throws IOException {
		if (fProjectStore == null) {
			fInstanceStore.save();
		} else {
			fProjectStore.save();
		}
	}
	
	public void revertChanges() throws IOException {
		if (fProjectStore != null) {
			// nothing to do
		} else {
			fInstanceStore.load();
		}
	}

	public void addTemplateData(TemplatePersistenceData data) {
		if (fProjectStore != null) {
			fProjectStore.add(data);
		} else {
			fInstanceStore.add(data);
		}
	}

	public void delete(TemplatePersistenceData data) {
		if (fProjectStore != null) {
			fProjectStore.delete(data);
		} else {
			fInstanceStore.delete(data);
		}
	}
}
