Copyright (c) 2000, 2018 IBM Corporation and others.
This program and the accompanying materials
are made available under the terms of the Eclipse Public License 2.0
which accompanies this distribution, and is available at
https://www.eclipse.org/legal/epl-2.0/
SPDX-License-Identifier: EPL-2.0
Contributors:
    IBM Corporation - initial API and implementation
/*******************************************************************************
 * Copyright (c) 2000, 2018 IBM Corporation and others.
 *
 * This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License 2.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-2.0/
 *
 * SPDX-License-Identifier: EPL-2.0
 *
 * Contributors:
 *     IBM Corporation - initial API and implementation
 *******************************************************************************/
package org.eclipse.jdt.internal.core.manipulation;

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.osgi.service.prefs.BackingStoreException;

import org.eclipse.core.runtime.Assert;
import org.eclipse.core.runtime.preferences.IEclipsePreferences;

import org.eclipse.core.resources.IProject;
import org.eclipse.core.resources.ProjectScope;

import org.eclipse.text.templates.TemplatePersistenceData;
import org.eclipse.text.templates.TemplateReaderWriter;
import org.eclipse.text.templates.TemplateStoreCore;

import org.eclipse.jface.text.templates.Template;

import org.eclipse.jdt.core.manipulation.JavaManipulation;

Since:
3.1/**
 * @since 3.1
 */
public final class ProjectTemplateStore {

	private static final String KEY= "org.eclipse.jdt.ui.text.custom_code_templates"; //$NON-NLS-1$

	private final TemplateStoreCore fInstanceStore;
	private final TemplateStoreCore fProjectStore;

	public ProjectTemplateStore(IProject project) {
		fInstanceStore= JavaManipulation.getCodeTemplateStore();
		if (project == null) {
			fProjectStore= null;
		} else {
			final IEclipsePreferences projectSettings= new ProjectScope(project).getNode(JavaManipulation.getPreferenceNodeId());
			fProjectStore= new TemplateStoreCore(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) {
					internalAdd(data);
				}

				@Override
				public void save() throws IOException {

					TemplatePersistenceData[] templateData= ProjectTemplateStore.this.getTemplateData();
					for (int i= 0; i < templateData.length; i++) {
						if (isProjectSpecific(templateData[i].getId())) {
							StringWriter output= new StringWriter();
							TemplateReaderWriter writer= new TemplateReaderWriter();
							writer.save(getTemplateData(false), output);

							projectSettings.put(KEY, output.toString());
							try {
								projectSettings.flush();
							} catch (BackingStoreException e) {
							}

							return;
						}
					}

					// See IPreferenceStore for default String value
					projectSettings.put(KEY, ""); //$NON-NLS-1$
					try {
						projectSettings.flush();
					} catch (BackingStoreException e) {
					}
				}
			};
		}
	}

	public static boolean hasProjectSpecificTempates(IProject project) {
		String pref= new ProjectScope(project).getNode(JavaManipulation.getPreferenceNodeId()).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);
		} else {
			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<>();
			TemplatePersistenceData[] data= fProjectStore.getTemplateData(false);
			for (int i= 0; i < data.length; i++) {
				datas.add(data[i].getId());
			}

			data= fInstanceStore.getTemplateData(false);
			for (int i= 0; i < data.length; i++) {
				TemplatePersistenceData orig= data[i];
				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
		} else {
			data.setDeleted(!projectSpecific);
		}
	}

	public void restoreDefaults() {
		if (fProjectStore == null) {
			fInstanceStore.restoreDefaults(false);
		} else {
			try {
				load();
			} catch (IOException e) {
				JavaManipulationPlugin.log(e);
			}
		}
	}

	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();
		}
	}
}