001/*
002 * Copyright 2010-2013 JetBrains s.r.o.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.jetbrains.jet.lang.psi;
018
019import com.intellij.lang.ASTNode;
020import com.intellij.psi.PsiElement;
021import com.intellij.psi.PsiReference;
022import com.intellij.psi.PsiReferenceService;
023import com.intellij.psi.impl.source.resolve.reference.ReferenceProvidersRegistry;
024import org.jetbrains.annotations.NotNull;
025import org.jetbrains.annotations.Nullable;
026import org.jetbrains.jet.JetNodeTypes;
027import org.jetbrains.jet.lang.resolve.name.FqName;
028import org.jetbrains.jet.lang.resolve.name.Name;
029
030import java.util.List;
031
032public class JetNamespaceHeader extends JetReferenceExpression {
033    private String qualifiedNameCache = null;
034
035    public JetNamespaceHeader(@NotNull ASTNode node) {
036        super(node);
037    }
038
039    @NotNull
040    public List<JetSimpleNameExpression> getParentNamespaceNames() {
041        List<JetSimpleNameExpression> parentParts = findChildrenByType(JetNodeTypes.REFERENCE_EXPRESSION);
042        JetSimpleNameExpression lastPart = (JetSimpleNameExpression)findLastChildByType(JetNodeTypes.REFERENCE_EXPRESSION);
043        parentParts.remove(lastPart);
044        return parentParts;
045    }
046
047    @Nullable
048    public JetSimpleNameExpression getLastPartExpression() {
049        return (JetSimpleNameExpression)findLastChildByType(JetNodeTypes.REFERENCE_EXPRESSION);
050    }
051
052    @NotNull
053    @Override
054    public PsiReference[] getReferences() {
055        return ReferenceProvidersRegistry.getReferencesFromProviders(this, PsiReferenceService.Hints.NO_HINTS);
056    }
057
058    @Nullable
059    @Override
060    public PsiReference getReference() {
061        PsiReference[] references = getReferences();
062        return references.length == 1 ? references[0] : null;
063    }
064
065    @Nullable
066    public PsiElement getNameIdentifier() {
067        JetSimpleNameExpression lastPart = (JetSimpleNameExpression)findLastChildByType(JetNodeTypes.REFERENCE_EXPRESSION);
068        if (lastPart == null) {
069            return null;
070        }
071
072        return lastPart.getIdentifier();
073    }
074
075    @Override
076    @NotNull
077    public String getName() {
078        PsiElement nameIdentifier = getNameIdentifier();
079        return nameIdentifier == null ? "" : nameIdentifier.getText();
080    }
081
082    @NotNull
083    public Name getNameAsName() {
084        PsiElement nameIdentifier = getNameIdentifier();
085        return nameIdentifier == null ? JetPsiUtil.ROOT_NAMESPACE_NAME : Name.identifier(nameIdentifier.getText());
086    }
087
088    public boolean isRoot() {
089        return getName().length() == 0;
090    }
091
092    @NotNull
093    public FqName getFqName() {
094        String qualifiedName = getQualifiedName();
095        return qualifiedName.isEmpty() ? FqName.ROOT : new FqName(qualifiedName);
096    }
097
098    @NotNull
099    public FqName getParentFqName(JetReferenceExpression nameExpression) {
100        String parentQualifiedName = getQualifiedNameParentOf(nameExpression);
101        return parentQualifiedName.isEmpty() ? FqName.ROOT : new FqName(parentQualifiedName);
102    }
103
104    @NotNull
105    public String getQualifiedName() {
106        if (qualifiedNameCache == null) {
107            qualifiedNameCache = getQualifiedNameParentOf(null);
108        }
109
110        return qualifiedNameCache;
111    }
112
113    @NotNull
114    private String getQualifiedNameParentOf(@Nullable JetReferenceExpression nameExpression) {
115        StringBuilder builder = new StringBuilder();
116        for (JetSimpleNameExpression e : findChildrenByClass(JetSimpleNameExpression.class)) {
117            if (e == nameExpression) {
118                break;
119            }
120
121            if (builder.length() > 0) {
122                builder.append(".");
123            }
124            builder.append(e.getReferencedName());
125        }
126        return builder.toString();
127    }
128
129    @Override
130    public void subtreeChanged() {
131        qualifiedNameCache = null;
132    }
133}
134