java/java-impl/src/com/intellij/codeInsight/hint/ShowContainerInfoHandler.java

   1 /*
   2  * Copyright 2000-2009 JetBrains s.r.o.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  * http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16 package com.intellij.codeInsight.hint;
  17
  18 import com.intellij.codeInsight.CodeInsightActionHandler;
  19 import com.intellij.ide.structureView.StructureViewBuilder;
  20 import com.intellij.ide.structureView.StructureViewModel;
  21 import com.intellij.ide.structureView.TreeBasedStructureViewBuilder;
  22 import com.intellij.lang.LanguageStructureViewBuilder;
  23 import com.intellij.openapi.application.ApplicationManager;
  24 import com.intellij.openapi.editor.Editor;
  25 import com.intellij.openapi.editor.LogicalPosition;
  26 import com.intellij.openapi.project.Project;
  27 import com.intellij.openapi.util.Key;
  28 import com.intellij.openapi.util.TextRange;
  29 import com.intellij.psi.*;
  30 import com.intellij.psi.xml.XmlFile;
  31 import com.intellij.psi.xml.XmlTag;
  32 import com.intellij.ui.LightweightHint;
  33 import org.jetbrains.annotations.NotNull;
  34 import org.jetbrains.annotations.Nullable;
  35
  36 import java.awt.*;
  37 import java.lang.ref.WeakReference;
  38
  39 public class ShowContainerInfoHandler implements CodeInsightActionHandler {
  40   private static final Key<WeakReference<LightweightHint>> MY_LAST_HINT_KEY = Key.create("MY_LAST_HINT_KEY");
  41   private static final Key<PsiElement> CONTAINER_KEY = Key.create("CONTAINER_KEY");
  42
  43   public void invoke(@NotNull final Project project, @NotNull final Editor editor, @NotNull PsiFile file) {
  44     PsiDocumentManager.getInstance(project).commitAllDocuments();
  45
  46     PsiElement container = null;
  47     WeakReference<LightweightHint> ref = editor.getUserData(MY_LAST_HINT_KEY);
  48     if (ref != null){
  49       LightweightHint hint = ref.get();
  50       if (hint != null && hint.isVisible()){
  51         hint.hide();
  52         container = hint.getUserData(CONTAINER_KEY);
  53         if (!container.isValid()){
  54           container = null;
  55         }
  56       }
  57     }
  58
  59     if (container == null){
  60       int offset = editor.getCaretModel().getOffset();
  61       container = file.findElementAt(offset);
  62       if (container == null) return;
  63     }
  64
  65     if (file instanceof PsiJavaFile || file instanceof XmlFile) {
  66       while(true){
  67         container = findContainer(container);
  68         if (container == null) return;
  69         if (!isDeclarationVisible(container, editor)) break;
  70       }
  71     }
  72     else {
  73       container = null;
  74       StructureViewBuilder builder = LanguageStructureViewBuilder.INSTANCE.getStructureViewBuilder(file);
  75       if (builder instanceof TreeBasedStructureViewBuilder) {
  76         StructureViewModel model = ((TreeBasedStructureViewBuilder) builder).createStructureViewModel();
  77         Object element = model.getCurrentEditorElement();
  78         if (element instanceof PsiElement) {
  79           container = (PsiElement) element;
  80           while(true) {
  81             if (container == null || container instanceof PsiFile) {
  82               return;
  83             }
  84             if (!isDeclarationVisible(container, editor)) {
  85               break;
  86             }
  87
  88             container = container.getParent();
  89             while(container != null && DeclarationRangeUtil.getPossibleDeclarationAtRange(container) == null) {
  90               container = container.getParent();
  91               if (container instanceof PsiFile) return;
  92             }
  93           }
  94         }
  95       }
  96       if (container == null) {
  97         return;
  98       }
  99     }
 100
 101     final TextRange range = DeclarationRangeUtil.getDeclarationRange(container);
 102     final PsiElement _container = container;
 103     ApplicationManager.getApplication().invokeLater(new Runnable() {
 104         public void run() {
 105           LightweightHint hint = EditorFragmentComponent.showEditorFragmentHint(editor, range, true);
 106           hint.putUserData(CONTAINER_KEY, _container);
 107           editor.putUserData(MY_LAST_HINT_KEY, new WeakReference<LightweightHint>(hint));
 108         }
 109       });
 110   }
 111
 112   public boolean startInWriteAction() {
 113     return false;
 114   }
 115
 116   @Nullable
 117   private static PsiElement findContainer(PsiElement element) {
 118     PsiElement container = element.getParent();
 119     while(true){
 120       if (container instanceof PsiFile) return null;
 121       if (container instanceof PsiMethod || container instanceof PsiClass || container instanceof PsiClassInitializer) break;
 122       if (container instanceof XmlTag) break;
 123       container = container.getParent();
 124     }
 125     return container;
 126   }
 127
 128   private static boolean isDeclarationVisible(PsiElement container, Editor editor) {
 129     Rectangle viewRect = editor.getScrollingModel().getVisibleArea();
 130     final TextRange range = DeclarationRangeUtil.getPossibleDeclarationAtRange(container);
 131     if (range == null) {
 132       return false;
 133     }
 134
 135     LogicalPosition pos = editor.offsetToLogicalPosition(range.getStartOffset());
 136     Point loc = editor.logicalPositionToXY(pos);
 137     return loc.y >= viewRect.y;
 138   }
 139 }