/*

 * Copyright (c) 2014, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

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 */

import com.sun.tools.classfile.Attribute;

import com.sun.tools.classfile.ClassFile;

import com.sun.tools.classfile.SourceFile_attribute;

import java.util.ArrayList;

import java.util.List;

import java.util.Map;

import javax.tools.JavaFileObject;

/**

 * Base class for Source file attribute tests. Checks expected file name for specified classes in the SourceFile attribute.

 * To add new tests you should extend the SourceFileTestBase class and invoke {@link #test} for static sources

 * or {@link #compileAndTest} for generated sources. For more information see corresponding methods.

 *

 * @see #test

 * @see #compileAndTest

 */

public class SourceFileTestBase extends TestBase {

    /**

     * Checks expected fileName for the specified class in the SourceFile attribute.

     *

     * @param classToTest class to check its SourceFile attribute

     * @param fileName    expected name of the file from which the test file is compiled.

     */

    protected void test(Class<?> classToTest, String fileName) throws Exception {

        assertAttributePresent(ClassFile.read(getClassFile(classToTest)), fileName);

    }

    /**

     * Checks expected fileName for the specified class in the SourceFile attribute.

     *

     * @param classToTest class name to check its SourceFile attribute

     * @param fileName    expected name of the file from which the test file is compiled.

     */

    protected void test(String classToTest, String fileName) throws Exception {

        assertAttributePresent(ClassFile.read(getClassFile(classToTest + ".class")), fileName);

    }

    /**

     * Compiles sourceCode and for each specified class name checks the SourceFile attribute.

     * The file name is extracted from source code.

     *

     * @param sourceCode    source code to compile

     * @param classesToTest class names to check their SourceFile attribute.

     */

    protected void compileAndTest(String sourceCode, String... classesToTest) throws Exception {

        Map<String, ? extends JavaFileObject> classes = compile(sourceCode).getClasses();

        String fileName = ToolBox.getJavaFileNameFromSource(sourceCode);

        for (String className : classesToTest) {

            assertAttributePresent(ClassFile.read(classes.get(className).openInputStream()), fileName);

        }

    }

    private void assertAttributePresent(ClassFile classFile, String fileName) throws Exception {

        //We need to count attributes with the same names because there is no appropriate API in the ClassFile.

        List<SourceFile_attribute> sourceFileAttributes = new ArrayList<>();

        for (Attribute a : classFile.attributes.attrs) {

            if (Attribute.SourceFile.equals(a.getName(classFile.constant_pool))) {

                sourceFileAttributes.add((SourceFile_attribute) a);

            }

        }

        assertEquals(sourceFileAttributes.size(), 1, "Should be the only SourceFile attribute");

        SourceFile_attribute attribute = sourceFileAttributes.get(0);

        assertEquals(classFile.constant_pool.getUTF8Info(attribute.attribute_name_index).value,

                Attribute.SourceFile, "Incorrect attribute name");

        assertEquals(classFile.constant_pool.getUTF8Info(attribute.sourcefile_index).value, fileName,

                "Incorrect source file name");

        assertEquals(attribute.attribute_length, 2, "Incorrect attribute length");

    }

}