DartStructureViewElement.java

package com.jetbrains.lang.dart.ide.structure;

import com.intellij.ide.structureView.StructureViewTreeElement;
import com.intellij.ide.structureView.impl.common.PsiTreeElementBase;
import com.intellij.navigation.ItemPresentation;
import com.intellij.psi.NavigatablePsiElement;
import com.intellij.psi.PsiElement;
import com.intellij.psi.ResolveState;
import com.jetbrains.lang.dart.psi.*;
import com.jetbrains.lang.dart.psi.impl.DartPsiCompositeElementImpl;
import com.jetbrains.lang.dart.resolve.ComponentNameScopeProcessor;
import com.jetbrains.lang.dart.util.DartResolveUtil;
import gnu.trove.THashSet;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;

import java.util.*;

public class DartStructureViewElement extends PsiTreeElementBase<NavigatablePsiElement>
  implements ItemPresentation, StructureViewTreeElement {
  public DartStructureViewElement(@NotNull final NavigatablePsiElement element) {
    super(element);
  }

  @NotNull
  @Override
  public Collection<StructureViewTreeElement> getChildrenBase() {
    final NavigatablePsiElement element = getElement();
    final List<StructureViewTreeElement> result = new ArrayList<>();

    if (element instanceof DartFile || element instanceof DartEmbeddedContent) {
      THashSet<DartComponentName> componentNames = new THashSet<>();
      DartPsiCompositeElementImpl
        .processDeclarationsImpl(element, new ComponentNameScopeProcessor(componentNames), ResolveState.initial(), null);
      for (DartComponentName componentName : componentNames) {
        PsiElement parent = componentName.getParent();
        if (parent instanceof DartComponent) {
          result.add(new DartStructureViewElement((DartComponent)parent));
        }
      }
    }
    else if (element instanceof DartClass) {
      for (DartComponent subNamedComponent : DartResolveUtil.getNamedSubComponents((DartClass)element)) {
        result.add(new DartStructureViewElement(subNamedComponent));
      }
    }

    Collections.sort(result, (o1, o2) -> {
      PsiElement element1, element2;
      if (o1 instanceof DartStructureViewElement &&
          o2 instanceof DartStructureViewElement &&
          (element1 = ((DartStructureViewElement)o1).getElement()) != null &&
          (element2 = ((DartStructureViewElement)o2).getElement()) != null) {
        return element1.getTextRange().getStartOffset() - element2.getTextRange().getStartOffset();
      }
      return 0;
    });

    return result;
  }

  @Nullable
  @Override
  public String getPresentableText() {
    final NavigatablePsiElement element = getElement();
    final ItemPresentation presentation = element == null ? null : element.getPresentation();
    return presentation == null ? null : presentation.getPresentableText();
  }
}