/*
 * (c) Copyright IBM Corp. 2000, 2001.
 * All Rights Reserved.
 */
package net.sourceforge.phpdt.internal.ui.text.template;

import net.sourceforge.phpdt.internal.corext.template.Template;
import net.sourceforge.phpdt.internal.corext.template.TemplateBuffer;
import net.sourceforge.phpdt.internal.corext.template.TemplateContext;
import net.sourceforge.phpdt.internal.corext.template.TemplateMessages;
import net.sourceforge.phpdt.internal.corext.template.TemplatePosition;
import net.sourceforge.phpdt.internal.corext.template.php.PHPTemplateMessages;
import net.sourceforge.phpdt.internal.corext.template.php.PHPUnitContext;
import net.sourceforge.phpdt.internal.ui.text.link.LinkedPositionManager;
import net.sourceforge.phpdt.internal.ui.text.link.LinkedPositionUI;
import net.sourceforge.phpeclipse.PHPeclipsePlugin;

import org.eclipse.core.runtime.CoreException;
import org.eclipse.jface.text.BadLocationException;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.IRegion;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.contentassist.IContextInformation;
import org.eclipse.swt.graphics.Image;
//import org.eclipse.jdt.internal.ui.text.link.LinkedPositionManager;
//import org.eclipse.jdt.internal.ui.text.link.LinkedPositionUI;
//import org.eclipse.jdt.internal.ui.util.ExceptionHandler;

/**
 * A template proposal.
 */
public class TemplateProposal extends AbstractProposal {
  private final TemplateContext fContext;
  private final Image fImage;
  private String fOldText;
  private final IRegion fRegion;

  private final Template fTemplate;

  private TemplateBuffer fTemplateBuffer;

  /**
   * Creates a template proposal with a template and its context.
   * @param template  the template
   * @param context   the context in which the template was requested.
   * @param image     the icon of the proposal.
   */
  public TemplateProposal(Template template, TemplateContext context, IRegion region, ITextViewer viewer, Image image) {
    super(viewer);

    fTemplate = template;
    fContext = context;
    //    fViewer = viewer;
    fImage = image;
    fRegion = region;
  }

  private static int getCaretOffset(TemplateBuffer buffer) {
    TemplatePosition[] variables = buffer.getVariables();
    for (int i = 0; i != variables.length; i++) {
      TemplatePosition variable = variables[i];

      if (variable.getName().equals(PHPTemplateMessages.getString("GlobalVariables.variable.name.cursor"))) //$NON-NLS-1$
        return variable.getOffsets()[0];
    }

    return buffer.getString().length();
  }

  /*
   * @see ICompletionProposal#apply(IDocument)
   */
  public void apply(IDocument document) {
    try {
      if (fTemplateBuffer == null)
        fTemplateBuffer = fContext.evaluate(fTemplate);

      int start = fRegion.getOffset();
      int end = fRegion.getOffset() + fRegion.getLength();

      // insert template string
      String templateString = fTemplateBuffer.getString();
      document.replace(start, end - start, templateString);

      // translate positions
      LinkedPositionManager manager = new LinkedPositionManager(document);
      TemplatePosition[] variables = fTemplateBuffer.getVariables();
      for (int i = 0; i != variables.length; i++) {
        TemplatePosition variable = variables[i];

        if (variable.isResolved())
          continue;

        int[] offsets = variable.getOffsets();
        int length = variable.getLength();

        for (int j = 0; j != offsets.length; j++)
          manager.addPosition(offsets[j] + start, length);
      }

      LinkedPositionUI editor = new LinkedPositionUI(fViewer, manager);
      editor.setFinalCaretOffset(getCaretOffset(fTemplateBuffer) + start);
      editor.enter();

      fSelectedRegion = editor.getSelectedRegion();

    } catch (BadLocationException e) {
      PHPeclipsePlugin.log(e);
      openErrorDialog(e);

    } catch (CoreException e) {
      handleException(e);
    }
  }

  /*
   * @see ICompletionProposal#getAdditionalProposalInfo()
   */
  public String getAdditionalProposalInfo() {
    try {
      if (fTemplateBuffer == null)
        fTemplateBuffer = fContext.evaluate(fTemplate);

      return textToHTML(fTemplateBuffer.getString());

    } catch (CoreException e) {
      handleException(e);
      return null;
    }
  }

  /*
   * @see ICompletionProposal#getContextInformation()
   */
  public IContextInformation getContextInformation() {
    return null;
  }

  /*
   * @see ICompletionProposal#getDisplayString()
   */
  public String getDisplayString() {
    return fTemplate.getName() + TemplateMessages.getString("TemplateProposal.delimiter") + fTemplate.getDescription(); // $NON-NLS-1$ //$NON-NLS-1$
  }

  /*
   * @see ICompletionProposal#getImage()
   */
  public Image getImage() {
    return fImage;
  }

  /*
   * @see IJavaCompletionProposal#getRelevance()
   */
  public int getRelevance() {

    if (fContext instanceof PHPUnitContext) {
      PHPUnitContext context = (PHPUnitContext) fContext;
      switch (context.getCharacterBeforeStart()) {
        // high relevance after whitespace
        case ' ' :
        case '\r' :
        case '\n' :
        case '\t' :
          return 90;

        default :
          return 0;
      }
    } else {
      return 90;
    }
  }

}