/*
    * Copyright (C) 2007-2012 Argeo GmbH
    *
    * Licensed under the Apache License, Version 2.0 (the "License");
    * you may not use this file except in compliance with the License.
    * You may obtain a copy of the License at
    *
    *         http://www.apache.org/licenses/LICENSE-2.0
    *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an "AS IS" BASIS,
   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  package org.argeo.slc.client.ui.editors;
  
  import java.text.DateFormat;
  import java.text.SimpleDateFormat;
  import java.util.List;
  import java.util.SortedMap;
  import java.util.TreeMap;
  
  import javax.jcr.Node;
  import javax.jcr.NodeIterator;
  import javax.jcr.RepositoryException;
  import javax.jcr.Workspace;
  import javax.jcr.observation.Event;
  import javax.jcr.observation.EventListener;
  import javax.jcr.query.Query;
  
  import org.argeo.eclipse.ui.jcr.AsyncUiEventListener;
  import org.argeo.slc.SlcException;
  import org.argeo.slc.SlcNames;
  import org.argeo.slc.SlcTypes;
  import org.argeo.slc.execution.ExecutionStep;
  import org.eclipse.swt.SWT;
  import org.eclipse.swt.widgets.Composite;
  import org.eclipse.swt.widgets.Control;
  import org.eclipse.swt.widgets.Display;
  import org.eclipse.swt.widgets.Text;
  import org.eclipse.ui.forms.editor.FormEditor;
  import org.eclipse.ui.forms.editor.FormPage;
  import org.eclipse.ui.forms.widgets.FormToolkit;
  
  public class ProcessLogPage extends FormPage {
  	public final static String ID = "processLogPage";
  
  	private DateFormat dateFormat = new SimpleDateFormat("HH:mm:ss");
  
  	/** Where the log is displayed. */
  	private Text text;
  	/**
  	 * Stores logs received before the text was shown. TODO : rather store in in
  	 * JCR and reads it from there.
  	 */
  	private StringBuffer beforeTextInit = new StringBuffer("");
  
  	private Node processNode;
  	/**
  	 * optimization field: we compute once the length of the path to slc:log so
  	 * that we can easily substring the relative path of logs.
  	 */
  	//private Integer logPathLength;
  
  	public ProcessLogPage(FormEditor editor, Node processNode) {
  		super(editor, ID, "Log");
  		this.processNode = processNode;
  
  		EventListener listener = new LogListener(editor.getSite().getPage()
  				.getWorkbenchWindow().getWorkbench().getDisplay());
  
  		try {
  			String logBasePath = processNode.getPath() + '/' + SlcNames.SLC_LOG;
  			//logPathLength = logBasePath.length();
  
  			Workspace ws = processNode.getSession().getWorkspace();
  
  			String statement = "SELECT * FROM ["
  					+ SlcTypes.SLC_LOG_ENTRY
  					+ "] as logEntry"
  					+ " WHERE ISDESCENDANTNODE('"
  					+ logBasePath
  					+ "')"
  					+ " ORDER BY logEntry.[slc:timestamp] ASC, NAME(logEntry) ASC";
  			StringBuffer buf = new StringBuffer("");
  			NodeIterator it = ws.getQueryManager()
  					.createQuery(statement, Query.JCR_SQL2).execute()
  					.getNodes();
  			while (it.hasNext())
  				appendLogEntry(buf, it.nextNode());
  			beforeTextInit = new StringBuffer(buf.toString());
  			// text.setText(buf.toString());
  			ws.getObservationManager().addEventListener(listener,
  					Event.NODE_ADDED, logBasePath, true, null, null, false);
  		} catch (RepositoryException e) {
  			throw new SlcException("Cannot register listener", e);
  		}
  	}
 
 	@Override
 	public synchronized void createPartControl(Composite parent) {
 		// bypass createFormContent
 		FormToolkit tk = getEditor().getToolkit();
 		// parent.setLayout(new FillLayout());
 		text = tk.createText(parent, "", SWT.MULTI | SWT.H_SCROLL
 				| SWT.V_SCROLL);
 		text.setEditable(false);
 
 		// transfer the existing buffer the first time
 		if (beforeTextInit.length() > 0) {
 			text.append(beforeTextInit.toString());
 			// clear buffer
 			beforeTextInit.setLength(0);
 		}
 
 	}
 
 	// @Override
 	// protected synchronized void createFormContent(IManagedForm mf) {
 	// ScrolledForm form = mf.getForm();
 	// form.setExpandHorizontal(true);
 	// form.setExpandVertical(true);
 	// // form.setText("Log");
 	// FillLayout mainLayout = new FillLayout();
 	// form.getBody().setLayout(mainLayout);
 	//
 	// FormToolkit tk = getManagedForm().getToolkit();
 	// text = tk.createText(form.getBody(), "", SWT.MULTI | SWT.H_SCROLL
 	// | SWT.V_SCROLL);
 	// text.setEditable(false);
 	// // transfer the existing buffer the first time
 	// if (beforeTextInit.length() > 0) {
 	// text.append(beforeTextInit.toString());
 	// // clear buffer
 	// beforeTextInit.setLength(0);
 	// }
 	// }
 
 	protected void appendLogEntry(StringBuffer buf, Node logEntry)
 			throws RepositoryException {
 		// +1 in order to remove the first slash
 //		String relPath = logEntry.getPath().substring(logPathLength + 1);
 		//System.out.println("relPath=" + relPath);
 //		int firstSlashIndex = relPath.indexOf('/');
 //		int lastSlashIndex = relPath.lastIndexOf('/');
 //		String thread = relPath.substring(0, firstSlashIndex);
 //		String location = relPath.substring(firstSlashIndex, lastSlashIndex);
 
 		// String date = dateFormat.format(logEntry
 		// .getProperty(SlcNames.SLC_TIMESTAMP).getDate().getTime());
 		String date = logEntry.getProperty(SlcNames.SLC_TIMESTAMP).getString();
 		buf.append(date).append(' ');
 		String type = logEntry.getPrimaryNodeType().getName().substring(7);
 		buf.append(type).append('\t');
 		// buf.append(thread).append('\t');
 		// buf.append(location).append('\t');
 		buf.append(logEntry.getProperty(SlcNames.SLC_MESSAGE).getString());
 		buf.append('\n');
 
 	}
 
 	/** @deprecated */
 	public synchronized void addSteps(List<ExecutionStep> steps) {
 		final StringBuffer buf = new StringBuffer("");
 		for (ExecutionStep step : steps) {
 			buf.append(dateFormat.format(step.getTimestamp()));
 			buf.append(' ');
 			if (step.getType().equals(ExecutionStep.PHASE_START)) {
 				buf.append("## START ").append(step.getLog());
 				buf.append('\n');
 			} else if (step.getType().equals(ExecutionStep.PHASE_END)) {
 				buf.append("## END   ").append(step.getLog());
 				buf.append("\n");
 			} else {
 				buf.append(step.getLog());
 			}
 		}
 
 		if (text != null) {
 			Display.getDefault().asyncExec(new Runnable() {
 				public void run() {
 					text.append(buf.toString());
 				}
 			});
 		} else
 			beforeTextInit.append(buf);
 	}
 
 	@Override
 	public Control getPartControl() {
 		return text;
 	}
 
 	@Override
 	public void setFocus() {
 		if (text != null)
 			text.setFocus();
 	}
 
 	/** JCR event listener notifying when new nodes are added */
 	private class LogListener extends AsyncUiEventListener {
 
 		public LogListener(Display display) {
 			super(display);
 		}
 
 		@Override
 		protected void onEventInUiThread(List<Event> events)
 				throws RepositoryException {
 			// since we use batch save, order is not guaranteed
 			// so we need to reorder, according to log line number for the time
 			// being
 			SortedMap<Long, Node> nodes = new TreeMap<Long, Node>();
 
 			for (Event evt : events) {
 				Node newNode = ProcessLogPage.this.processNode.getSession()
 						.getNode(evt.getPath());
 				if (newNode.isNodeType(SlcTypes.SLC_LOG_ENTRY)) {
 					nodes.put(Long.parseLong(newNode.getName()), newNode);
 				}
 			}
 
 			StringBuffer buf = new StringBuffer("");
 			for (Node logEntry : nodes.values()) {
 				appendLogEntry(buf, logEntry);
 			}
 
 			if (text != null)
 				text.append(buf.toString());
 			else
 				beforeTextInit.append(buf);
 		}
 	}
 }