/*******************************************************************************
 * Copyright (c) 2001, 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.wst.xsd.ui.internal.common.properties.sections;

import java.util.Map;

import org.apache.xerces.util.XMLChar;
import org.eclipse.core.resources.IFile;
import org.eclipse.jface.viewers.IStructuredSelection;
import org.eclipse.jface.viewers.ViewerFilter;
import org.eclipse.jface.window.Window;
import org.eclipse.jface.wizard.WizardDialog;
import org.eclipse.swt.SWT;
import org.eclipse.swt.custom.CLabel;
import org.eclipse.swt.custom.StyledText;
import org.eclipse.swt.events.SelectionEvent;
import org.eclipse.swt.layout.GridData;
import org.eclipse.swt.layout.GridLayout;
import org.eclipse.swt.widgets.Composite;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.Event;
import org.eclipse.swt.widgets.Shell;
import org.eclipse.swt.widgets.Text;
import org.eclipse.ui.IEditorInput;
import org.eclipse.ui.IFileEditorInput;
import org.eclipse.ui.PlatformUI;
import org.eclipse.wst.common.ui.internal.viewers.ResourceFilter;
import org.eclipse.wst.common.uriresolver.internal.util.URIHelper;
import org.eclipse.wst.xsd.ui.internal.editor.XSDEditorCSHelpIds;
import org.eclipse.wst.xsd.ui.internal.editor.XSDEditorPlugin;
import org.eclipse.wst.xsd.ui.internal.util.TypesHelper;
import org.eclipse.wst.xsd.ui.internal.wizards.XSDSelectIncludeFileWizard;
import org.eclipse.xsd.XSDImport;
import org.eclipse.xsd.XSDSchema;
import org.eclipse.xsd.impl.XSDImportImpl;
import org.eclipse.xsd.util.XSDConstants;
import org.w3c.dom.Element;

public class XSDImportSection extends SchemaLocationSection
{
  protected Text namespaceText, prefixText;
  protected String oldPrefixValue;

  public XSDImportSection()
  {
    super();
  }

  /**
   * @see org.eclipse.wst.common.ui.properties.internal.provisional.ITabbedPropertySection#createControls(org.eclipse.swt.widgets.Composite,
   *      org.eclipse.wst.common.ui.properties.internal.provisional.TabbedPropertySheetWidgetFactory)
   */
  public void createContents(Composite parent)
  {
    composite = getWidgetFactory().createFlatFormComposite(parent);

    GridLayout gridLayout = new GridLayout();
    gridLayout.marginTop = 0;
    gridLayout.marginBottom = 0;
    gridLayout.numColumns = 3;
    composite.setLayout(gridLayout);

    GridData data = new GridData();

    // Create Schema Location Label
    CLabel namespaceLabel = getWidgetFactory().createCLabel(composite, XSDEditorPlugin.getXSDString("_UI_LABEL_NAMESPACE")); //$NON-NLS-1$
    data.horizontalAlignment = GridData.HORIZONTAL_ALIGN_BEGINNING;
    data.grabExcessHorizontalSpace = false;
    namespaceLabel.setLayoutData(data);

    namespaceText = getWidgetFactory().createText(composite, "", SWT.NONE); //$NON-NLS-1$
    namespaceText.setEditable(false);
    data = new GridData();
    data.grabExcessHorizontalSpace = true;
    data.horizontalAlignment = GridData.FILL;
    applyAllListeners(namespaceText);
    namespaceText.setLayoutData(data);

    // ------------------------------------------------------------------
    // DummyLabel
    // ------------------------------------------------------------------
    data = new GridData();
    data.horizontalAlignment = GridData.HORIZONTAL_ALIGN_BEGINNING;
    data.grabExcessHorizontalSpace = false;
    getWidgetFactory().createCLabel(composite, ""); //$NON-NLS-1$

    CLabel prefixLabel = getWidgetFactory().createCLabel(composite, XSDEditorPlugin.getXSDString("_UI_LABEL_PREFIX")); //$NON-NLS-1$
    data = new GridData();
    data.horizontalAlignment = GridData.HORIZONTAL_ALIGN_BEGINNING;
    data.grabExcessHorizontalSpace = false;
    prefixLabel.setLayoutData(data);

    prefixText = getWidgetFactory().createText(composite, "", SWT.NONE); //$NON-NLS-1$
    prefixText.setEditable(true);
    applyAllListeners(prefixText);
    data = new GridData();
    data.grabExcessHorizontalSpace = true;
    data.horizontalAlignment = GridData.FILL;
    prefixText.setLayoutData(data);

    // ------------------------------------------------------------------
    // DummyLabel
    // ------------------------------------------------------------------
    data = new GridData();
    data.horizontalAlignment = GridData.HORIZONTAL_ALIGN_BEGINNING;
    data.grabExcessHorizontalSpace = false;
    getWidgetFactory().createCLabel(composite, ""); //$NON-NLS-1$

    // Create Schema Location Label
    CLabel schemaLocationLabel = getWidgetFactory().createCLabel(composite, XSDEditorPlugin.getXSDString("_UI_LABEL_SCHEMA_LOCATION")); //$NON-NLS-1$
    data = new GridData();
    data.horizontalAlignment = GridData.HORIZONTAL_ALIGN_BEGINNING;
    data.grabExcessHorizontalSpace = false;
    schemaLocationLabel.setLayoutData(data);

    // Create Schema Location Text
    schemaLocationText = getWidgetFactory().createText(composite, "", SWT.NONE); //$NON-NLS-1$
    schemaLocationText.setEditable(true);
    applyAllListeners(schemaLocationText);

    data = new GridData();
    data.grabExcessHorizontalSpace = true;
    data.horizontalAlignment = GridData.FILL;
    schemaLocationText.setLayoutData(data);

    // Create Wizard Button
    wizardButton = getWidgetFactory().createButton(composite, "", SWT.NONE); //$NON-NLS-1$
    wizardButton.setImage(XSDEditorPlugin.getXSDImage("icons/browsebutton.gif")); //$NON-NLS-1$
    data = new GridData();
    data.horizontalAlignment = GridData.HORIZONTAL_ALIGN_BEGINNING;
    data.grabExcessHorizontalSpace = false;
    wizardButton.setLayoutData(data);
    wizardButton.addSelectionListener(this);

    // error text
    errorText = new StyledText(composite, SWT.FLAT);
    errorText.setEditable(false);
    errorText.setEnabled(false);
    errorText.setText(""); //$NON-NLS-1$

    data = new GridData();
    data.horizontalAlignment = GridData.FILL;
    data.horizontalSpan = 3;
    data.grabExcessHorizontalSpace = true;
    errorText.setLayoutData(data);

    PlatformUI.getWorkbench().getHelpSystem().setHelp(schemaLocationText,
    		XSDEditorCSHelpIds.GENERAL_TAB__IMPORT__SCHEMALOCATION);

    PlatformUI.getWorkbench().getHelpSystem().setHelp(namespaceText,
    		XSDEditorCSHelpIds.GENERAL_TAB__IMPORT__NAMESPACE);
    
    PlatformUI.getWorkbench().getHelpSystem().setHelp(prefixText,
    		XSDEditorCSHelpIds.GENERAL_TAB__IMPORT__PREFIX);

  }

  public void refresh()
  {
    setListenerEnabled(false);

    errorText.setText("");
    Element element = null;
    if (input instanceof XSDImport)
    {
      element = ((XSDImport) input).getElement();

      String namespace = element.getAttribute("namespace"); //$NON-NLS-1$
      String schemaLocation = element.getAttribute("schemaLocation"); //$NON-NLS-1$

      TypesHelper helper = new TypesHelper(xsdSchema);
      String prefix = helper.getPrefix(element.getAttribute(XSDConstants.NAMESPACE_ATTRIBUTE), false);

      if (namespace == null)
      {
        namespace = ""; //$NON-NLS-1$
      }

      if (prefix == null)
      {
        prefix = ""; //$NON-NLS-1$
      }

      if (schemaLocation == null)
      {
        schemaLocation = ""; //$NON-NLS-1$
      }

      namespaceText.setText(namespace);
      prefixText.setText(prefix);
      schemaLocationText.setText(schemaLocation);
      oldPrefixValue = prefixText.getText();
    }

    setListenerEnabled(true);
  }

  public void widgetSelected(SelectionEvent event)
  {
    if (event.widget == wizardButton)
    {
      setListenerEnabled(false);
      Shell shell = Display.getCurrent().getActiveShell();

      IFile currentIFile = null;
      IEditorInput editorInput = getActiveEditor().getEditorInput();
      ViewerFilter filter;
      if (editorInput instanceof IFileEditorInput)
      {
        currentIFile = ((IFileEditorInput)editorInput).getFile();
        filter = new ResourceFilter(new String[] { ".xsd" }, //$NON-NLS-1$ 
            new IFile[] { currentIFile }, null);
      }
      else
      {
        filter = new ResourceFilter(new String[] { ".xsd" }, //$NON-NLS-1$ 
            null, null);
      }

      XSDSelectIncludeFileWizard fileSelectWizard = new XSDSelectIncludeFileWizard(xsdSchema, false, XSDEditorPlugin.getXSDString("_UI_FILEDIALOG_SELECT_XML_SCHEMA"), //$NON-NLS-1$
          XSDEditorPlugin.getXSDString("_UI_FILEDIALOG_SELECT_XML_DESC"), //$NON-NLS-1$
          filter, (IStructuredSelection) getSelection());

      WizardDialog wizardDialog = new WizardDialog(shell, fileSelectWizard);
      wizardDialog.create();
      wizardDialog.setBlockOnOpen(true);
      int result = wizardDialog.open();

      String value = schemaLocationText.getText();
      prefixText.removeListener(SWT.Modify, this);
      if (result == Window.OK)
      {
        errorText.setText("");
        IFile selectedIFile = fileSelectWizard.getResultFile();
        String schemaFileString = value;
        if (selectedIFile != null && currentIFile != null)
        {
          schemaFileString = URIHelper.getRelativeURI(selectedIFile.getLocation(), currentIFile.getLocation());
        }
        else if (selectedIFile != null && currentIFile == null)
        {
          schemaFileString = selectedIFile.getLocationURI().toString();
        }
        else
        {
          schemaFileString = fileSelectWizard.getURL();
        }

        String namespace = fileSelectWizard.getNamespace();
        if (namespace == null)
          namespace = "";

        XSDSchema externalSchema = fileSelectWizard.getExternalSchema();
        handleSchemaLocationChange(schemaFileString, namespace, externalSchema);
      }
      setListenerEnabled(true);
      prefixText.addListener(SWT.Modify, this);
//      }
//      else
//      {
//        BrowseInWorkspaceAction browseInWorkspace = new BrowseInWorkspaceAction(shell);
//        browseInWorkspace.run();
//        IFile selectedIFile = browseInWorkspace.getSelectedFile();
//        String value = schemaLocationText.getText();
//        String schemaFileString = value;
//        if (selectedIFile != null) 
//        {
//          //schemaFileString = URIHelper.getRelativeURI(selectedIFile.getLocation(), currentIFile.getLocation());
//          schemaFileString = selectedIFile.getLocationURI().toString();
//          handleSchemaLocationChange(schemaFileString, "", null);
//          refresh();
//        }
//
//      }
    }
  }

  protected void handleSchemaLocationChange(String schemaFileString, String namespace, XSDSchema externalSchema)
  {
    if (input instanceof XSDImport)
    {
      XSDImport xsdImport = (XSDImport) input;

      xsdImport.setNamespace(namespace);
      xsdImport.setSchemaLocation(schemaFileString);
      xsdImport.setResolvedSchema(externalSchema);

      java.util.Map map = xsdSchema.getQNamePrefixToNamespaceMap();

      // Referential integrity on old import
      // How can we be sure that if the newlocation is the same as the
      // oldlocation
      // the file hasn't changed

//      XSDSchema referencedSchema = xsdImport.getResolvedSchema();
//      if (referencedSchema != null)
//      {
//        XSDExternalFileCleanup cleanHelper = new
//        XSDExternalFileCleanup(referencedSchema);
//        cleanHelper.visitSchema(xsdSchema);
//      }

      Element schemaElement = xsdSchema.getElement();

      // update the xmlns in the schema element first, and then update the
      // import element next
      // so that the last change will be in the import element. This keeps the
      // selection
      // on the import element
      TypesHelper helper = new TypesHelper(externalSchema);
      String prefix = helper.getPrefix(namespace, false);

      if (map.containsKey(prefix))
      {
        prefix = null;
      }

      if (prefix == null || (prefix != null && prefix.length() == 0))
      {
        StringBuffer newPrefix = new StringBuffer("pref"); //$NON-NLS-1$
        int prefixExtension = 1;
        while (map.containsKey(newPrefix.toString()) && prefixExtension < 100)
        {
          newPrefix = new StringBuffer("pref" + String.valueOf(prefixExtension));
          prefixExtension++;
        }
        prefix = newPrefix.toString();
      }

      if (namespace.length() > 0)
      {
        // if ns already in map, use its corresponding prefix
        if (map.containsValue(namespace))
        {
          TypesHelper typesHelper = new TypesHelper(xsdSchema);
          prefix = typesHelper.getPrefix(namespace, false);
        }
        else
        // otherwise add to the map
        {
          schemaElement.setAttribute("xmlns:" + prefix, namespace);
        }
        prefixText.setText(prefix);
      }
      else
      {
        prefixText.setText("");
        namespaceText.setText("");
      }
      
      // See https://bugs.eclipse.org/bugs/show_bug.cgi?id=155885
      // Need to import otherwise the external schema is never
      // resolved.  One problem is that the schema location is still null,
      // so the set types dialog will show types that belong to that schema
      // with a null schema location.  This should load resource 
      // into the resource set
      if (input instanceof XSDImportImpl)  // redundant
      {
        XSDImportImpl xsdImportImpl = (XSDImportImpl) input;
        xsdImportImpl.importSchema();
      }
    }
    refresh();
  }

  public void doHandleEvent(Event event)
  {
    setErrorMessage(null);
    super.doHandleEvent(event);
    if (event.widget == prefixText)
    {
      String newPrefix = prefixText.getText();
      if (oldPrefixValue.equals(newPrefix) || !isValidSchemaLocation)
        return;
      Map map = xsdSchema.getQNamePrefixToNamespaceMap();
      String key = prefixText.getText();      
      if (key.length() == 0) key = null;
      
      if (validatePrefix(newPrefix) && schemaLocationText.getText().trim().length() > 0)
      {
        if (map.containsKey(key))
        {
          setErrorMessage(XSDEditorPlugin.getXSDString("_ERROR_LABEL_PREFIX_EXISTS"));
        }
        else
        {
          Element schemaElement = xsdSchema.getElement();
          
          if (key != null) {
            if (oldPrefixValue.length() == 0) 
              schemaElement.removeAttribute("xmlns");
            else 
              schemaElement.removeAttribute("xmlns:"+oldPrefixValue);
            
            schemaElement.setAttribute("xmlns:" + newPrefix, namespaceText.getText());
          } 
          else {
            schemaElement.removeAttribute("xmlns:"+oldPrefixValue);
            schemaElement.setAttribute("xmlns", namespaceText.getText());
          }
          xsdSchema.updateElement();
          setErrorMessage(null);
          oldPrefixValue = newPrefix;
        }
      }
      else
      {
        setErrorMessage(XSDEditorPlugin.getXSDString("_ERROR_LABEL_INVALID_PREFIX"));
      }
    }
  }

  public void aboutToBeHidden()
  {
    setErrorMessage(null);
    super.aboutToBeHidden();
  }
  
  protected boolean validatePrefix(String prefix)
  {
    if (prefix.length() == 0) return true;
    return XMLChar.isValidNCName(prefix);
  }
}