platform/core-impl/src/com/intellij/psi/impl/source/resolve/FileContextUtil.java

/*
 * Copyright 2000-2009 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (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.apache.org/licenses/LICENSE-2.0
 *
 * 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.intellij.psi.impl.source.resolve;

import com.intellij.openapi.util.Key;
import com.intellij.psi.PsiElement;
import com.intellij.psi.PsiFile;
import com.intellij.psi.SmartPsiElementPointer;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

/**
 * @author max
 */
public class FileContextUtil {
  public static final Key<SmartPsiElementPointer> INJECTED_IN_ELEMENT = Key.create("injectedIn");
  public static final Key<PsiFile> CONTAINING_FILE_KEY = Key.create("CONTAINING_FILE_KEY");

  private FileContextUtil() { }

  @Nullable
  public static PsiElement getFileContext(@NotNull PsiFile file) {
    SmartPsiElementPointer pointer = file.getUserData(INJECTED_IN_ELEMENT);
    return pointer == null ? null : pointer.getElement();
  }

  @Nullable
  public static PsiFile getContextFile(@NotNull PsiElement element) {
    if (!element.isValid()) return null;
    PsiFile file = element.getContainingFile();
    if (file == null) return null;
    PsiElement context = file.getContext();
    if (context == null) {
      return file;
    }
    else {
      return getContextFile(context);
    }
  }
}