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.plugin;
018    
019    import org.jetbrains.annotations.NotNull;
020    import org.jetbrains.annotations.Nullable;
021    import org.jetbrains.jet.lang.psi.*;
022    
023    import java.util.Collection;
024    import java.util.List;
025    
026    public class JetMainDetector {
027        private JetMainDetector() {
028        }
029    
030        public static boolean hasMain(@NotNull List<JetDeclaration> declarations) {
031            return findMainFunction(declarations) != null;
032        }
033    
034        public static boolean isMain(@NotNull JetNamedFunction function) {
035            if ("main".equals(function.getName())) {
036                List<JetParameter> parameters = function.getValueParameters();
037                if (parameters.size() == 1) {
038                    JetTypeReference reference = parameters.get(0).getTypeReference();
039                    if (reference != null && reference.getText().equals("Array<String>")) {  // TODO correct check
040                        return true;
041                    }
042                }
043            }
044            return false;
045        }
046    
047        @Nullable
048        public static JetNamedFunction getMainFunction(@NotNull Collection<JetFile> files) {
049            for (JetFile file : files) {
050                JetNamedFunction mainFunction = findMainFunction(file.getDeclarations());
051                if (mainFunction != null) {
052                    return mainFunction;
053                }
054            }
055            return null;
056        }
057    
058        @Nullable
059        private static JetNamedFunction findMainFunction(@NotNull List<JetDeclaration> declarations) {
060            for (JetDeclaration declaration : declarations) {
061                if (declaration instanceof JetNamedFunction) {
062                    JetNamedFunction candidateFunction = (JetNamedFunction) declaration;
063                    if (isMain(candidateFunction)) {
064                        return candidateFunction;
065                    }
066                }
067            }
068            return null;
069        }
070    }