/**
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
 *  under the License.
 */
package org.codehaus.groovy.tools.javac;

import groovy.lang.GroovyClassLoader;
import org.codehaus.groovy.ast.ClassNode;
import org.codehaus.groovy.classgen.GeneratorContext;
import org.codehaus.groovy.classgen.VariableScopeVisitor;
import org.codehaus.groovy.control.CompilationFailedException;
import org.codehaus.groovy.control.CompilationUnit;
import org.codehaus.groovy.control.CompilerConfiguration;
import org.codehaus.groovy.control.Phases;
import org.codehaus.groovy.control.SourceUnit;

import java.io.File;
import java.io.FileNotFoundException;
import java.net.URL;
import java.util.Map;

/**
 * Compilation unit to only generate stubs.
 *
 * @author <a href="mailto:jason@planet57.com">Jason Dillon</a>
 * @author Guillaume Laforge
 */
public class JavaStubCompilationUnit extends CompilationUnit {
    private static final String DOT_GROOVY = ".groovy";

    private final JavaStubGenerator stubGenerator;

    private int stubCount;

    public JavaStubCompilationUnit(final CompilerConfiguration config, final GroovyClassLoader gcl, File destDir) {
        super(config, null, gcl);
        assert config != null;

        Map options = config.getJointCompilationOptions();
        if (destDir == null) {
            destDir = (File) options.get("stubDir");
        }
        boolean useJava5 = CompilerConfiguration.isPostJDK5(configuration.getTargetBytecode());
		String encoding = configuration.getSourceEncoding();
        stubGenerator = new JavaStubGenerator(destDir, false, useJava5, encoding);

        addPhaseOperation(new PrimaryClassNodeOperation() {
            @Override
            public void call(SourceUnit source, GeneratorContext context, ClassNode node) throws CompilationFailedException {
                VariableScopeVisitor scopeVisitor = new VariableScopeVisitor(source);
                scopeVisitor.visitClass(node);
                new JavaAwareResolveVisitor(JavaStubCompilationUnit.this).startResolving(node, source);
            }
        }, Phases.CONVERSION);
        addPhaseOperation(new PrimaryClassNodeOperation() {
            @Override
            public void call(final SourceUnit source, final GeneratorContext context, final ClassNode node) throws CompilationFailedException {
                try {
                    stubGenerator.generateClass(node);
                    stubCount++;
                } catch (FileNotFoundException e) {
                    source.addException(e);
                }
            }
        }, Phases.CONVERSION);
    }

    public JavaStubCompilationUnit(final CompilerConfiguration config, final GroovyClassLoader gcl) {
        this(config, gcl, null);
    }

    public int getStubCount() {
        return stubCount;
    }

    @Override
    public void compile() throws CompilationFailedException {
        stubCount = 0;
        super.compile(Phases.CONVERSION);
    }

    @Override
    public void configure(final CompilerConfiguration config) {
        super.configure(config);
        // GroovyClassLoader should be able to find classes compiled from java sources
        File targetDir = config.getTargetDirectory();
        if (targetDir != null) {
            final String classOutput = targetDir.getAbsolutePath();
            getClassLoader().addClasspath(classOutput);
        }
    }

    @Override
    public SourceUnit addSource(final File file) {
        if (hasAcceptedFileExtension(file.getName())) {
            return super.addSource(file);
        }
        return null;
    }

    @Override
    public SourceUnit addSource(URL url) {
        if (hasAcceptedFileExtension(url.getPath())) {
            return super.addSource(url);
        }
        return null;
    }

    private boolean hasAcceptedFileExtension(String name) {
        String lowerCasedName = name.toLowerCase();
        for (String extension : configuration.getScriptExtensions()) {
            if (lowerCasedName.endsWith(extension))
                return true;
        }
        return false;
    }
}
