/*
    *  
    *  Fosstrak LLRP Commander (www.fosstrak.org)
    * 
    *  Copyright (C) 2008 ETH Zurich
    *
    *  This program is free software: you can redistribute it and/or modify
    *  it under the terms of the GNU General Public License as published by
    *  the Free Software Foundation, either version 3 of the License, or
   *  (at your option) any later version.
   *
   *  This program is distributed in the hope that it will be useful,
   *  but WITHOUT ANY WARRANTY; without even the implied warranty of
   *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   *  GNU General Public License for more details.
   *
   *  You should have received a copy of the GNU General Public License
   *  along with this program.  If not, see <http://www.gnu.org/licenses/> 
   *
   */
  
  package org.fosstrak.llrp.commander.preferences.pref;
  
  import java.util.HashMap;
  import java.util.Map;
  
  import org.apache.log4j.Logger;
  import org.eclipse.core.runtime.IStatus;
  import org.eclipse.core.runtime.Status;
  import org.eclipse.jface.dialogs.ErrorDialog;
  import org.eclipse.jface.preference.FieldEditor;
  import org.eclipse.swt.SWT;
  import org.eclipse.swt.events.SelectionAdapter;
  import org.eclipse.swt.events.SelectionEvent;
  import org.eclipse.swt.graphics.Font;
  import org.eclipse.swt.layout.GridData;
  import org.eclipse.swt.layout.GridLayout;
  import org.eclipse.swt.widgets.Button;
  import org.eclipse.swt.widgets.Combo;
  import org.eclipse.swt.widgets.Composite;
  import org.eclipse.swt.widgets.Control;
  import org.eclipse.swt.widgets.Group;
  import org.eclipse.swt.widgets.Label;
  import org.eclipse.swt.widgets.Shell;
  import org.eclipse.swt.widgets.Text;
  import org.fosstrak.llrp.adaptor.AdaptorManagement;
  import org.fosstrak.llrp.client.Repository;
  import org.fosstrak.llrp.client.RepositoryFactory;
  import org.fosstrak.llrp.client.repository.sql.MySQLRepository;
  import org.fosstrak.llrp.client.repository.sql.PostgreSQLRepository;
  import org.fosstrak.llrp.commander.LLRPPlugin;
  import org.fosstrak.llrp.commander.ResourceCenter;
  import org.fosstrak.llrp.commander.preferences.PreferenceConstants;
  import org.llrp.ltk.generated.messages.RO_ACCESS_REPORT;
  
  /**
   * An extension of the {@link FieldEditor} supporting the grouping of several 
   * preferences into a nice group box. 
   * @author sawielan
   *
   */
  public class GroupedStringFieldEditor extends FieldEditor  {
  	
  	// the top level widget holding the whole graphical representation of the 
  	// preferences.
  	private Composite groupedFields;
  	
  	// how many columns to use in the groupedFields widget.
  	private int numColumns = 1;
  	
  	/** index of the text label in the preferencesLabelsAndNames array. */
  	public static final int INDEX_LABEL = 0;
  	
  	/** index of the preference name in the preferencesLabelsAndNames array. */
  	public static final int INDEX_PREF_NAME = 1;
  	
  	// the preferences widgets.
  	private Text[] preferences;
  	
  	// the label widgets.
  	private Label[] preferencesLabels;
  	
  	// the values of the preferences read from the preferences store.
  	private String[] preferencesValues;
  	
  	// a 2D array holding the labels and the names of the preferences.
  	private String[][] preferencesLabelsAndNames;
  	
  	// a handle to the repository (if test and switch is used).
  	private Repository repository = null;
  	
  	// log4j instance.
  	private static Logger log = Logger.getLogger(GroupedStringFieldEditor.class);
  	
  	
  	/**
  	 * A {@link FieldEditor} supporting the grouping of several preferences 
  	 * into a nice group box. 
  	 * @param labelText the text of the group box (example the title).
 	 * @param preferencesLabelsAndNames a 2D array providing the labels for the 
 	 * preferences in the first column, and the preferences names in the 
 	 * second column.<br/>
 	 * <h3>Example</h3>
 	 * <code>new String[][] {</code><br/>
 	 * <code>&nbsp;&nbsp;{"Implementor", PreferenceConstants.P_EXT_DB_IMPLEMENTOR },</code><br/>
 	 * <code>&nbsp;&nbsp;{"JDBC String", PreferenceConstants.P_EXT_DB_JDBC}</code><br/>
 	 * <code>}</code>
 	 * @param parent the parent widget of this editor.
 	 */
 	public GroupedStringFieldEditor(String labelText, 
 			String[][] preferencesLabelsAndNames, Composite parent) {
 		
 		this.preferencesLabelsAndNames = preferencesLabelsAndNames;
 		setLabelText(labelText);
 		this.numColumns = 2;
 		createControl(parent);
 	}
 	
 	/**
 	 * searches for a preference name in the preferences table.
 	 * @param prefName the name of the preference to search.
 	 * @return -1 if preference was not found, the index otherwise.
 	 */
 	private int getPrefIndex(String prefName) {
 		for (int i=0; i<preferencesLabelsAndNames.length; i++) {
 			if (preferencesLabelsAndNames[i][INDEX_PREF_NAME].equals(prefName)) {
 				return i;
 			}
 		}
 		return -1;
 	}
 	
 	/**
 	 * @return a hash map containing the settings for the repository creation.
 	 */
 	private Map<String, String> prepArgs() {
 		Map<String, String> args = new HashMap<String, String> ();
   	  	args.put(
   			  RepositoryFactory.ARG_WIPE_DB,
   			  String.format("%b", false));
   	  	
   	  	args.put(
   			  RepositoryFactory.ARG_WIPE_RO_ACCESS_REPORTS_DB, 
   			  String.format("%b", false));
   	  	
   	  	args.put(RepositoryFactory.ARG_USERNAME,
   			  preferences[getPrefIndex(PreferenceConstants.P_EXT_DB_USERNAME)]
   			              .getText());
   	  	
   	  	args.put(RepositoryFactory.ARG_PASSWRD,
   			  preferences[getPrefIndex(PreferenceConstants.P_EXT_DB_PWD)]
   			              .getText());
   	  	
   	  	args.put(RepositoryFactory.ARG_JDBC_STRING,
   			  preferences[getPrefIndex(PreferenceConstants.P_EXT_DB_JDBC)]
   			              .getText());
   	  	
   	  	args.put(RepositoryFactory.ARG_DB_CLASSNAME,
   			  preferences[getPrefIndex(PreferenceConstants.P_EXT_DB_IMPLEMENTOR)]
   			              .getText());
   	  	return args;
 	}
 	
 	/**
 	 * create the group providing the entries.
 	 * @param parent the parent of this widget.
 	 * @return a composite widget holding all the graphical elements.
 	 */
 	public Composite getDBFieldControl(Composite parent) {
 		if (null == groupedFields) {
 			Font font = parent.getFont();
 			
 			// create a nice group box (with the nice border around it).
 			Group group = new Group(parent, SWT.NONE);
 			group.setFont(font);
 			String text = getLabelText();
 			if (null != text) {
 				group.setText(text);
 			} 
 			groupedFields = group;
 			GridLayout layout = new GridLayout();
 			layout.horizontalSpacing = HORIZONTAL_GAP;
 			layout.numColumns = numColumns;
 			groupedFields.setLayout(layout);
 
 			final Shell shell = parent.getShell();
 			final Button buttonSwitch = new Button(groupedFields, SWT.BUTTON1);
 			buttonSwitch.setEnabled(false);
 			buttonSwitch.setText("Switch configuration");
 			buttonSwitch.addSelectionListener(new SelectionAdapter() {
 			      public void widgetSelected(SelectionEvent e) {
 			    	  // try to open the repository. if it works out, switch it.
 							
 			    	  try {
 						repository = RepositoryFactory.create(
 								prepArgs());
 						buttonSwitch.setEnabled(false);
 					
 						Repository old = ResourceCenter.getInstance().
 							setRepository(repository);
 						if (null != old.getROAccessRepository()) {
 							AdaptorManagement.getInstance().deregisterPartialHandler(
 									old.getROAccessRepository(), RO_ACCESS_REPORT.class);
 						}
 						// stop the old repository
 						try {
 							old.close();
 						} catch (Exception repoE) {
 							log.error("Old repository could not be stopped.");
 						}
 					} catch (Exception e1) {
 						IStatus status = new Status(
 								IStatus.ERROR, LLRPPlugin.PLUGIN_ID, 
 								"LLRP Repository Error.", e1);
 						ErrorDialog.openError(shell, 
 								"Repository Error", e1.getMessage(), status);
 						repository = null;
 					}
 			      }
 			    });
 			
 			final Button buttonTest = new Button(groupedFields, SWT.BUTTON1);
 			buttonTest.setText("Test configuration");
 			buttonTest.addSelectionListener(new SelectionAdapter() {
 			      public void widgetSelected(SelectionEvent e) {
 			    	  // try to open the repository. if it works out, switch it.
 			    	  Map<String, String> args = prepArgs();
 			    	  if (args.get(RepositoryFactory.ARG_DB_CLASSNAME).
 			    			  equals(
 			    					  ResourceCenter.getInstance()
 			    					  .getRepository().getClass().getName())) {
 			    		  log.debug("We not allow to set the same repository.");
 			    		  String notice = "Your selection is currently in use.";
 			    		  IStatus status = new Status(
 									IStatus.INFO, LLRPPlugin.PLUGIN_ID, 
 									notice);
 							ErrorDialog.openError(shell, 
 									"Please Notice: " + notice, 
 									notice, 
 									status);
 						return;
 					  }
 							
 			    	  try {
 						repository = RepositoryFactory.create(
 								args);
 						repository.close();
 						repository = null;
 						buttonSwitch.setEnabled(true);
 					} catch (Exception e1) {
 						IStatus status = new Status(
 								IStatus.ERROR, LLRPPlugin.PLUGIN_ID, 
 								"LLRP Repository Error.", e1);
 						ErrorDialog.openError(shell, 
 								"Repository Error", e1.getMessage(), status);
 						repository = null;
 					}
 			      }
 			    });
 			
 		
 			// create the graphical representation of the labels and the 
 			// preferences.
 			final int len = preferencesLabelsAndNames.length;
 			preferences = new Text[len];
 			preferencesLabels = new Label[len];
 			for (int i=0; i<len; i++) {
 				
 				if (preferencesLabelsAndNames[i][INDEX_PREF_NAME].equals(
 						PreferenceConstants.P_EXT_DB_IMPLEMENTOR)) {
 					// add some hints.
 					addImplementorHints(groupedFields);
 				} else if (preferencesLabelsAndNames[i][INDEX_PREF_NAME].equals(
 						PreferenceConstants.P_EXT_DB_JDBC)) {
 					// add some hints.
 					addJDBCHints(groupedFields);
 				}
 				
 				Label lbl = new Label(groupedFields, SWT.NONE);
 				lbl.setFont(font);
 				// add a nice : if not already provided by the label itself
 				String t = preferencesLabelsAndNames[i][INDEX_LABEL];
 				if (!t.endsWith(":")) {
 					t += ":";
 				}
 				lbl.setText(t);
 				preferencesLabels[i] = lbl;
 				
 				Text txt = new Text(groupedFields, SWT.BORDER);
 				txt.setFont(font);
 				// create a grid data element filling up the margin with the 
 				// text field so it fills out the whole space.
 				GridData gd = new GridData();
 				gd.horizontalSpan = numColumns - 1;
 				gd.horizontalAlignment = GridData.FILL;
 				gd.grabExcessHorizontalSpace = true;
 				txt.setLayoutData(gd);
 				preferences[i] = txt;
 			}
 		} else {
 			checkParent(groupedFields, parent);
 		}
 		return groupedFields;
 	}
 	
 	private void addJDBCHints(Composite parent) {
 		Label hints = new Label(parent, SWT.NONE);
 		hints.setText("Examples: ");
 		
 		final Combo combo = new Combo(parent, SWT.DROP_DOWN | SWT.READ_ONLY);
 		String[] items = new String [] {
 				MySQLRepository.JDBC_STR,
 				PostgreSQLRepository.JDBC_STR
 		};
 		combo.setItems(items);
 		combo.setBounds(0, 0, 200, 20);
 		combo.addSelectionListener(new SelectionAdapter() {
 		      public void widgetSelected(SelectionEvent e) {
 		    	  preferences[
     	              	getPrefIndex(PreferenceConstants.P_EXT_DB_JDBC)
     	              	].setText(combo.getItem(combo.getSelectionIndex()));
 		      }
 		    });
 	}
 
 	private void addImplementorHints(Composite parent) {
 		Label hints = new Label(parent, SWT.NONE);
 		hints.setText("Examples: ");
 		
 		final Combo combo = new Combo(parent, SWT.DROP_DOWN | SWT.READ_ONLY);
 		String[] items = new String [] {
 			MySQLRepository.class.getName(),
 			PostgreSQLRepository.class.getName()
 		};
 		combo.setItems(items);
 		combo.setBounds(0, 0, 200, 20);
 		combo.addSelectionListener(new SelectionAdapter() {
 		      public void widgetSelected(SelectionEvent e) {
 		    	  preferences[
     	              	getPrefIndex(PreferenceConstants.P_EXT_DB_IMPLEMENTOR)
     	              	].setText(combo.getItem(combo.getSelectionIndex()));
 		      }
 		    });
 	}
 
 	@Override
 	protected void createControl(Composite parent) {
 		GridLayout layout = new GridLayout();
 		layout.numColumns = getNumberOfControls();
 		layout.marginWidth = 0;
 		layout.marginHeight = 0;
 		layout.horizontalSpacing = HORIZONTAL_GAP;
 		parent.setLayout(layout);
 		doFillIntoGrid(parent, layout.numColumns);
 	}
 
 	@Override
 	protected void adjustForNumColumns(int numColumns) {
 		((GridData)groupedFields.getLayoutData()).horizontalSpan = numColumns;
 	}
 
 	@Override
 	protected void doFillIntoGrid(Composite parent, int numColumns) {
 		Control control = getDBFieldControl(parent);
 		GridData gd = new GridData(GridData.FILL_HORIZONTAL);
 		control.setLayoutData(gd);
 	}
 
 	@Override
 	protected void doLoad() {
 		final int len = preferencesLabelsAndNames.length;
 		preferencesValues = new String[len];
 		for (int i=0; i<len; i++) {
 			preferencesValues[i] = getPreferenceStore().getString(
 					preferencesLabelsAndNames[i][INDEX_PREF_NAME]);
 			preferences[i].setText(preferencesValues[i]);
 		}
 	}
 
 	@Override
 	protected void doLoadDefault() {
 		final int len = preferencesLabelsAndNames.length;
 		preferencesValues = new String[len];
 		for (int i=0; i<len; i++) {
 			preferencesValues[i] = getPreferenceStore().getDefaultString(
 					preferencesLabelsAndNames[i][INDEX_PREF_NAME]);
 			preferences[i].setText(preferencesValues[i]);
 		}
 	}
 	
 	@Override
 	protected void doStore() {
 		final int len = preferencesLabelsAndNames.length;
 		for (int i=0; i<len; i++) {
 			getPreferenceStore().setValue(
 					preferencesLabelsAndNames[i][INDEX_PREF_NAME], 
 					preferences[i].getText());
 		}
 	}
 
 	@Override
 	public int getNumberOfControls() {
 		return 1;
 	}
 }