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    
017    package org.jetbrains.jet.lang.resolve.scopes;
018    
019    import com.google.common.collect.Maps;
020    import com.google.common.collect.Sets;
021    import org.jetbrains.annotations.NotNull;
022    import org.jetbrains.annotations.Nullable;
023    import org.jetbrains.jet.lang.descriptors.*;
024    import org.jetbrains.jet.lang.resolve.name.LabelName;
025    import org.jetbrains.jet.lang.resolve.name.Name;
026    import org.jetbrains.jet.lang.types.TypeSubstitutor;
027    
028    import java.util.Collection;
029    import java.util.List;
030    import java.util.Map;
031    import java.util.Set;
032    
033    public class SubstitutingScope implements JetScope {
034    
035        private final JetScope workerScope;
036        private final TypeSubstitutor substitutor;
037    
038        private Map<DeclarationDescriptor, DeclarationDescriptor> substitutedDescriptors = null;
039        private Collection<DeclarationDescriptor> allDescriptors = null;
040    
041        public SubstitutingScope(JetScope workerScope, @NotNull TypeSubstitutor substitutor) {
042            this.workerScope = workerScope;
043            this.substitutor = substitutor;
044        }
045    
046        @Nullable
047        private <D extends DeclarationDescriptor> D substitute(@Nullable D descriptor) {
048            if (descriptor == null) return null;
049            if (substitutor.isEmpty()) return descriptor;
050    
051            if (substitutedDescriptors == null) {
052                substitutedDescriptors = Maps.newHashMap();
053            }
054    
055            DeclarationDescriptor substituted = substitutedDescriptors.get(descriptor);
056            if (substituted == null && !substitutedDescriptors.containsKey(descriptor)) {
057                substituted = descriptor.substitute(substitutor);
058    
059                //noinspection ConstantConditions
060                substitutedDescriptors.put(descriptor, substituted);
061            }
062    
063            //noinspection unchecked
064            return (D) substituted;
065        }
066    
067        @NotNull
068        private <D extends DeclarationDescriptor> Collection<D> substitute(@NotNull Collection<D> descriptors) {
069            if (substitutor.isEmpty()) return descriptors;
070            if (descriptors.isEmpty()) return descriptors;
071    
072            Set<D> result = Sets.newHashSetWithExpectedSize(descriptors.size());
073            for (D descriptor : descriptors) {
074                D substitute = substitute(descriptor);
075                if (substitute != null) {
076                    result.add(substitute);
077                }
078            }
079    
080            return result;
081        }
082    
083        @NotNull
084        @Override
085        public Collection<VariableDescriptor> getProperties(@NotNull Name name) {
086            return substitute(workerScope.getProperties(name));
087        }
088    
089        @Override
090        public VariableDescriptor getLocalVariable(@NotNull Name name) {
091            return substitute(workerScope.getLocalVariable(name));
092        }
093    
094        @Override
095        public ClassifierDescriptor getClassifier(@NotNull Name name) {
096            return substitute(workerScope.getClassifier(name));
097        }
098    
099        @Override
100        public ClassDescriptor getObjectDescriptor(@NotNull Name name) {
101            return substitute(workerScope.getObjectDescriptor(name));
102        }
103    
104        @NotNull
105        @Override
106        public Collection<ClassDescriptor> getObjectDescriptors() {
107            return substitute(workerScope.getObjectDescriptors());
108        }
109    
110        @NotNull
111        @Override
112        public Collection<FunctionDescriptor> getFunctions(@NotNull Name name) {
113            return substitute(workerScope.getFunctions(name));
114        }
115    
116        @Override
117        public NamespaceDescriptor getNamespace(@NotNull Name name) {
118            return workerScope.getNamespace(name); // TODO
119        }
120    
121        @NotNull
122        @Override
123        public List<ReceiverParameterDescriptor> getImplicitReceiversHierarchy() {
124            throw new UnsupportedOperationException(); // TODO
125        }
126    
127        @NotNull
128        @Override
129        public DeclarationDescriptor getContainingDeclaration() {
130            return workerScope.getContainingDeclaration();
131        }
132    
133        @NotNull
134        @Override
135        public Collection<DeclarationDescriptor> getDeclarationsByLabel(@NotNull LabelName labelName) {
136            throw new UnsupportedOperationException(); // TODO
137        }
138    
139        @Override
140        public PropertyDescriptor getPropertyByFieldReference(@NotNull Name fieldName) {
141            throw new UnsupportedOperationException(); // TODO
142        }
143    
144        @NotNull
145        @Override
146        public Collection<DeclarationDescriptor> getAllDescriptors() {
147            if (allDescriptors == null) {
148                allDescriptors = substitute(workerScope.getAllDescriptors());
149            }
150            return allDescriptors;
151        }
152    
153        @NotNull
154        @Override
155        public Collection<DeclarationDescriptor> getOwnDeclaredDescriptors() {
156            return substitute(workerScope.getOwnDeclaredDescriptors());
157        }
158    }