/*
 * Copyright (c) 2002-2004 Roberto Gonzalez Rocha 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:
 *     Roberto Gonzalez Rocha - Initial version
 *     Igor Malinin - refactoring, minor changes
 *
 * $Id: XMLSyntaxPreferencePage.java,v 1.1 2004-09-02 18:28:03 jsurfer Exp $
 */

package net.sourceforge.phpeclipse.xml.ui.internal.preferences;

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;

import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.jface.preference.PreferenceConverter;
import org.eclipse.jface.preference.PreferencePage;
import org.eclipse.jface.resource.JFaceResources;
import org.eclipse.jface.text.Document;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IDocumentPartitioner;
import org.eclipse.jface.text.source.ISourceViewer;
import org.eclipse.jface.text.source.SourceViewer;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.events.SelectionListener;
import org.eclipse.swt.graphics.Color;
import org.eclipse.swt.graphics.RGB;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.layout.RowLayout;
import org.eclipse.swt.widgets.Button;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Control;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Group;
import org.eclipse.swt.widgets.Label;
import org.eclipse.swt.widgets.List;
import org.eclipse.ui.IWorkbench;
import org.eclipse.ui.IWorkbenchPreferencePage;
import org.eclipse.ui.texteditor.AbstractTextEditor;

import net.sourceforge.phpeclipse.ui.ColorEditor;
import net.sourceforge.phpeclipse.ui.preferences.ITextStylePreferences;
import net.sourceforge.phpeclipse.ui.preferences.OverlayPreferenceStore;
import net.sourceforge.phpeclipse.ui.preferences.PreferenceDescriptor;
import net.sourceforge.phpeclipse.xml.ui.XMLPlugin;
import net.sourceforge.phpeclipse.xml.ui.internal.text.XMLConfiguration;
import net.sourceforge.phpeclipse.xml.ui.text.IXMLSyntaxConstants;
import net.sourceforge.phpeclipse.xml.ui.text.XMLTextTools;

/**
 * The XMLSyntaxPreferencePage is a preference page that handles setting the colors used by the XML editors.
 */
public class XMLSyntaxPreferencePage extends PreferencePage implements IWorkbenchPreferencePage {

  public final PreferenceDescriptor[] fKeys = new PreferenceDescriptor[] {
      new PreferenceDescriptor(PreferenceDescriptor.BOOLEAN, AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND_SYSTEM_DEFAULT),
      new PreferenceDescriptor(PreferenceDescriptor.STRING, AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND),

      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_DEFAULT
          + ITextStylePreferences.SUFFIX_FOREGROUND),
      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_DEFAULT + ITextStylePreferences.SUFFIX_STYLE),

      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_TAG + ITextStylePreferences.SUFFIX_FOREGROUND),
      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_TAG + ITextStylePreferences.SUFFIX_STYLE),

      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_ATT_NAME
          + ITextStylePreferences.SUFFIX_FOREGROUND),
      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_ATT_NAME + ITextStylePreferences.SUFFIX_STYLE),

      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_ATT_VALUE
          + ITextStylePreferences.SUFFIX_FOREGROUND),
      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_ATT_VALUE + ITextStylePreferences.SUFFIX_STYLE),

      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_ENTITY
          + ITextStylePreferences.SUFFIX_FOREGROUND),
      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_ENTITY + ITextStylePreferences.SUFFIX_STYLE),

      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_CDATA + ITextStylePreferences.SUFFIX_FOREGROUND),
      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_CDATA + ITextStylePreferences.SUFFIX_STYLE),

      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_PI + ITextStylePreferences.SUFFIX_FOREGROUND),
      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_PI + ITextStylePreferences.SUFFIX_STYLE),

      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_COMMENT
          + ITextStylePreferences.SUFFIX_FOREGROUND),
      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_COMMENT + ITextStylePreferences.SUFFIX_STYLE),

      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_DECL + ITextStylePreferences.SUFFIX_FOREGROUND),
      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_DECL + ITextStylePreferences.SUFFIX_STYLE),

      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_SMARTY + ITextStylePreferences.SUFFIX_FOREGROUND),
      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.XML_SMARTY + ITextStylePreferences.SUFFIX_STYLE), 
      
      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.DTD_CONDITIONAL
          + ITextStylePreferences.SUFFIX_FOREGROUND),
      new PreferenceDescriptor(PreferenceDescriptor.STRING, IXMLSyntaxConstants.DTD_CONDITIONAL
          + ITextStylePreferences.SUFFIX_STYLE),};

  OverlayPreferenceStore overlay;

  final String[][] fSyntaxColorListModel = new String[][] { { 
      XMLPlugin.getResourceString("XmlSyntaxPreferencePage.others"), //$NON-NLS-1$
      IXMLSyntaxConstants.XML_DEFAULT }, { XMLPlugin.getResourceString("XmlSyntaxPreferencePage.Tag"), //$NON-NLS-1$
      IXMLSyntaxConstants.XML_TAG }, { XMLPlugin.getResourceString("XmlSyntaxPreferencePage.AttName"), //$NON-NLS-1$
      IXMLSyntaxConstants.XML_ATT_NAME }, { XMLPlugin.getResourceString("XmlSyntaxPreferencePage.AttValue"), //$NON-NLS-1$
      IXMLSyntaxConstants.XML_ATT_VALUE }, { XMLPlugin.getResourceString("XmlSyntaxPreferencePage.Entity"), //$NON-NLS-1$
      IXMLSyntaxConstants.XML_ENTITY }, { XMLPlugin.getResourceString("XmlSyntaxPreferencePage.CDATA"), //$NON-NLS-1$
      IXMLSyntaxConstants.XML_CDATA }, { XMLPlugin.getResourceString("XmlSyntaxPreferencePage.PI"), //$NON-NLS-1$
      IXMLSyntaxConstants.XML_PI }, { XMLPlugin.getResourceString("XmlSyntaxPreferencePage.Comment"), //$NON-NLS-1$
      IXMLSyntaxConstants.XML_COMMENT }, { XMLPlugin.getResourceString("XmlSyntaxPreferencePage.Declaration"), //$NON-NLS-1$
      IXMLSyntaxConstants.XML_DECL }, { XMLPlugin.getResourceString("XmlSyntaxPreferencePage.Conditional"), //$NON-NLS-1$
      IXMLSyntaxConstants.XML_SMARTY }, { XMLPlugin.getResourceString("XmlSyntaxPreferencePage.SmartyTag"), //$NON-NLS-1$
      IXMLSyntaxConstants.DTD_CONDITIONAL }, 
          };

  private XMLTextTools xmlTextTools;

  private Color bgColor;

  Button bgDefault;

  Button bgCustom;

  ColorEditor bgColorEditor;

  List colors;

  ColorEditor fgColorEditor;

  Button fgBold;

  SourceViewer preview;

  /**
   * Constructor for XMLSyntaxPreferencePage.
   */
  public XMLSyntaxPreferencePage() {
    setDescription(XMLPlugin.getResourceString("XmlSyntaxPreferencePage.description")); //$NON-NLS-1$

    setPreferenceStore(XMLPlugin.getDefault().getPreferenceStore());

    overlay = new OverlayPreferenceStore(getPreferenceStore(), fKeys);
  }

  protected Control createContents(Composite parent) {
    overlay.load();
    overlay.start();

    Composite colorComposite = new Composite(parent, SWT.NULL);
    colorComposite.setLayout(new GridLayout());

    Group backgroundComposite = new Group(colorComposite, SWT.SHADOW_ETCHED_IN);

    backgroundComposite.setLayout(new RowLayout());
    backgroundComposite.setText(XMLPlugin.getResourceString("XmlSyntaxPreferencePage.backgroundColor")); //$NON-NLS-1$

    SelectionListener backgroundSelectionListener = new SelectionListener() {
      public void widgetSelected(SelectionEvent e) {
        boolean custom = bgCustom.getSelection();
        bgColorEditor.getButton().setEnabled(custom);
        overlay.setValue(AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND_SYSTEM_DEFAULT, !custom);
      }

      public void widgetDefaultSelected(SelectionEvent e) {
      }
    };

    bgDefault = new Button(backgroundComposite, SWT.RADIO | SWT.LEFT);
    bgDefault.setText(XMLPlugin.getResourceString("XmlSyntaxPreferencePage.systemDefault")); //$NON-NLS-1$
    bgDefault.addSelectionListener(backgroundSelectionListener);

    bgCustom = new Button(backgroundComposite, SWT.RADIO | SWT.LEFT);
    bgCustom.setText(XMLPlugin.getResourceString("XmlSyntaxPreferencePage.custom")); //$NON-NLS-1$
    bgCustom.addSelectionListener(backgroundSelectionListener);

    bgColorEditor = new ColorEditor(backgroundComposite);

    Label label = new Label(colorComposite, SWT.LEFT);
    label.setText(XMLPlugin.getResourceString("XmlSyntaxPreferencePage.foreground")); //$NON-NLS-1$
    label.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));

    Composite editorComposite = new Composite(colorComposite, SWT.NONE);
    GridLayout layout = new GridLayout();
    layout.numColumns = 2;
    layout.marginHeight = 0;
    layout.marginWidth = 0;
    editorComposite.setLayout(layout);
    GridData gd = new GridData(GridData.FILL_BOTH);
    editorComposite.setLayoutData(gd);

    colors = new List(editorComposite, SWT.SINGLE | SWT.V_SCROLL | SWT.BORDER);
    gd = new GridData(GridData.FILL_BOTH);
    gd.heightHint = convertHeightInCharsToPixels(5);
    colors.setLayoutData(gd);

    Composite stylesComposite = new Composite(editorComposite, SWT.NONE);
    layout = new GridLayout();
    layout.marginHeight = 0;
    layout.marginWidth = 0;
    layout.numColumns = 2;
    stylesComposite.setLayout(layout);
    stylesComposite.setLayoutData(new GridData(GridData.FILL_BOTH));

    label = new Label(stylesComposite, SWT.LEFT);
    label.setText(XMLPlugin.getResourceString("XmlSyntaxPreferencePage.color")); //$NON-NLS-1$
    gd = new GridData();
    gd.horizontalAlignment = GridData.BEGINNING;
    label.setLayoutData(gd);

    fgColorEditor = new ColorEditor(stylesComposite);

    Button fgColorButton = fgColorEditor.getButton();
    gd = new GridData(GridData.FILL_HORIZONTAL);
    gd.horizontalAlignment = GridData.BEGINNING;
    fgColorButton.setLayoutData(gd);

    label = new Label(stylesComposite, SWT.LEFT);
    label.setText(XMLPlugin.getResourceString("XmlSyntaxPreferencePage.bold")); //$NON-NLS-1$
    gd = new GridData();
    gd.horizontalAlignment = GridData.BEGINNING;
    label.setLayoutData(gd);

    fgBold = new Button(stylesComposite, SWT.CHECK);
    gd = new GridData(GridData.FILL_HORIZONTAL);
    gd.horizontalAlignment = GridData.BEGINNING;
    fgBold.setLayoutData(gd);

    label = new Label(colorComposite, SWT.LEFT);
    label.setText(XMLPlugin.getResourceString("XmlSyntaxPreferencePage.preview")); //$NON-NLS-1$
    label.setLayoutData(new GridData(GridData.FILL_HORIZONTAL));

    Control previewer = createPreviewer(colorComposite);
    gd = new GridData(GridData.FILL_BOTH);
    gd.widthHint = convertWidthInCharsToPixels(20);
    gd.heightHint = convertHeightInCharsToPixels(5);
    previewer.setLayoutData(gd);

    colors.addSelectionListener(new SelectionListener() {

      public void widgetDefaultSelected(SelectionEvent e) {
      }

      public void widgetSelected(SelectionEvent e) {
        handleSyntaxColorListSelection();
      }
    });

    bgColorEditor.getButton().addSelectionListener(new SelectionListener() {
      public void widgetDefaultSelected(SelectionEvent e) {
      }

      public void widgetSelected(SelectionEvent e) {
        PreferenceConverter.setValue(overlay, AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND, bgColorEditor.getColorValue());
      }
    });

    fgColorButton.addSelectionListener(new SelectionListener() {
      public void widgetDefaultSelected(SelectionEvent e) {
      }

      public void widgetSelected(SelectionEvent e) {
        int i = colors.getSelectionIndex();

        String key = fSyntaxColorListModel[i][1];

        PreferenceConverter.setValue(overlay, key + ITextStylePreferences.SUFFIX_FOREGROUND, fgColorEditor.getColorValue());
      }
    });

    fgBold.addSelectionListener(new SelectionListener() {
      public void widgetDefaultSelected(SelectionEvent e) {
      }

      public void widgetSelected(SelectionEvent e) {
        int i = colors.getSelectionIndex();

        String key = fSyntaxColorListModel[i][1];

        String value = (fgBold.getSelection()) ? ITextStylePreferences.STYLE_BOLD : ITextStylePreferences.STYLE_NORMAL;

        overlay.setValue(key + ITextStylePreferences.SUFFIX_STYLE, value);
      }
    });

    initialize();

    return colorComposite;
  }

  private Control createPreviewer(Composite parent) {
    xmlTextTools = new XMLTextTools(overlay); // REVISIT: DTD

    preview = new SourceViewer(parent, null, SWT.V_SCROLL | SWT.H_SCROLL | SWT.BORDER);

    preview.configure(new XMLConfiguration(xmlTextTools));
    preview.getTextWidget().setFont(JFaceResources.getFontRegistry().get(JFaceResources.TEXT_FONT));
    preview.setEditable(false);

    initializeViewerColors(preview);

    String content = loadPreviewContentFromFile("preview.xml"); //$NON-NLS-1$
    IDocument document = new Document(content);

    // REVISIT: DTD
    IDocumentPartitioner partitioner = xmlTextTools.createXMLPartitioner();

    partitioner.connect(document);
    document.setDocumentPartitioner(partitioner);

    preview.setDocument(document);

    overlay.addPropertyChangeListener(new IPropertyChangeListener() {
      public void propertyChange(PropertyChangeEvent event) {
        String p = event.getProperty();
        if (p.equals(AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND)
            || p.equals(AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND_SYSTEM_DEFAULT)) {
          initializeViewerColors(preview);
        }

        preview.invalidateTextPresentation();
      }
    });

    return preview.getControl();
  }

  /**
   * Initializes the given viewer's colors.
   * 
   * @param viewer
   *          the viewer to be initialized
   */
  void initializeViewerColors(ISourceViewer viewer) {
    if (overlay != null) {
      StyledText styledText = viewer.getTextWidget();

      // ---------- background color ----------------------
      Color color = null;
      if (!overlay.getBoolean(AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND_SYSTEM_DEFAULT)) {
        color = createColor(overlay, AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND, styledText.getDisplay());
      }

      styledText.setBackground(color);

      if (bgColor != null) {
        bgColor.dispose();
      }

      bgColor = color;
    }
  }

  /**
   * Creates a color from the information stored in the given preference store. Returns <code>null</code> if there is no such
   * information available.
   */
  private Color createColor(IPreferenceStore store, String key, Display display) {
    RGB rgb = null;

    if (store.contains(key)) {
      if (store.isDefault(key)) {
        rgb = PreferenceConverter.getDefaultColor(store, key);
      } else {
        rgb = PreferenceConverter.getColor(store, key);
      }

      if (rgb != null) {
        return new Color(display, rgb);
      }
    }

    return null;
  }

  void handleSyntaxColorListSelection() {
    int i = colors.getSelectionIndex();

    String key = fSyntaxColorListModel[i][1];

    RGB rgb = PreferenceConverter.getColor(overlay, key + ITextStylePreferences.SUFFIX_FOREGROUND);

    fgColorEditor.setColorValue(rgb);

    // REVISIT
    fgBold.setSelection(overlay.getString(key + ITextStylePreferences.SUFFIX_STYLE).indexOf(ITextStylePreferences.STYLE_BOLD) >= 0);
  }

  private String loadPreviewContentFromFile(String filename) {
    StringBuffer string = new StringBuffer(512);

    try {
      char[] buf = new char[512];
      BufferedReader reader = new BufferedReader(new InputStreamReader(XMLSyntaxPreferencePage.class.getResourceAsStream(filename)));

      try {
        while (true) {
          int n = reader.read(buf);
          if (n < 0) {
            break;
          }

          string.append(buf, 0, n);
        }
      } finally {
        reader.close();
      }
    } catch (IOException e) {
    }

    return string.toString();
  }

  /**
   *  
   */
  private void initialize() {
    initializeFields();

    for (int i = 0; i < fSyntaxColorListModel.length; i++) {
      colors.add(fSyntaxColorListModel[i][0]);
    }

    colors.getDisplay().asyncExec(new Runnable() {

      public void run() {
        colors.select(0);
        handleSyntaxColorListSelection();
      }
    });
  }

  private void initializeFields() {
    RGB rgb = PreferenceConverter.getColor(overlay, AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND);
    bgColorEditor.setColorValue(rgb);

    boolean def = overlay.getBoolean(AbstractTextEditor.PREFERENCE_COLOR_BACKGROUND_SYSTEM_DEFAULT);
    bgDefault.setSelection(def);
    bgCustom.setSelection(!def);
    bgColorEditor.getButton().setEnabled(!def);
  }

  /*
   * @see IWorkbenchPreferencePage#init(IWorkbench)
   */
  public void init(IWorkbench workbench) {
  }

  /*
   * @see PreferencePage#performDefaults()
   */
  protected void performDefaults() {
    overlay.loadDefaults();
    //initializeFields();
    handleSyntaxColorListSelection();

    super.performDefaults();

    preview.invalidateTextPresentation();
  }

  /*
   * @see org.eclipse.jface.preference.IPreferencePage#performOk()
   */
  public boolean performOk() {
    overlay.propagate();
    XMLPlugin.getDefault().savePluginPreferences();

    return true;
  }

  /*
   * @see org.eclipse.jface.dialogs.IDialogPage#dispose()
   */
  public void dispose() {
    if (xmlTextTools != null) {
      xmlTextTools.dispose();
      xmlTextTools = null;
    }

    if (overlay != null) {
      overlay.stop();
      overlay = null;
    }

    super.dispose();
  }
}