/*
 * Copyright (c) 2013, the Dart project authors.
 * 
 * Licensed under the Eclipse Public License v1.0 (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.eclipse.org/legal/epl-v10.html
 * 
 * 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 com.google.dart.tools.ui.internal.text.completion;

import com.google.dart.tools.core.completion.CompletionProposal;
import com.google.dart.tools.ui.DartPluginImages;

import org.eclipse.jface.text.DocumentEvent;
import org.eclipse.jface.text.IDocument;
import org.eclipse.jface.text.ITextViewer;
import org.eclipse.jface.text.source.SourceViewer;
import org.eclipse.jface.viewers.StyledString;
import org.eclipse.swt.widgets.Display;

public class OptionalArgumentCompletionProposal extends AbstractDartCompletionProposal {
  private final String name;
  private final String type;

  public OptionalArgumentCompletionProposal(CompletionProposal proxy) {
    setReplacementOffset(proxy.getReplaceStart());
    setReplacementLength(proxy.getReplaceEnd() - proxy.getReceiverStart());
    String completion = "";
    setReplacementString(completion);
    setSortString(completion);
    setCursorPosition(completion.length());
    name = proxy.getParameterName();
    type = proxy.getParameterType();
    setImage(DartPluginImages.get(DartPluginImages.IMG_MISC_PROTECTED));
    setRelevance(proxy.getRelevance() * 100); // needs to be higher than computeRelevance()
  }

  @Override
  public void apply(IDocument document, char trigger, int offset) {
    super.apply(document, trigger, offset);
  }

  @Override
  public void apply(ITextViewer viewer, char trigger, int stateMask, int offset) {
    super.apply(viewer, trigger, stateMask, offset);
    showValueProposals(viewer);
  }

  @Override
  public StyledString getStyledDisplayString() {
    return new StyledString("[" + type + " " + name + "]");
  }

  @Override
  public boolean validate(IDocument document, int offset, DocumentEvent event) {
    return super.validate(document, offset, event);
  }

  @Override
  protected boolean isValidPrefix(String prefix) {
    return isPrefix(prefix, name);
  }

  private void showValueProposals(final ITextViewer viewer) {
    Display.getDefault().asyncExec(new Runnable() {
      @Override
      public void run() {
        ((SourceViewer) viewer).doOperation(SourceViewer.CONTENTASSIST_PROPOSALS);
      }
    });
  }
}