/*

 * 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

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 */

import java.io.PrintWriter;

import java.io.StringWriter;

import java.util.ArrayList;

import java.util.List;

import java.util.regex.Matcher;

import java.util.regex.Pattern;

/*

 * @test

 * @bug 8038414

 * @summary Constant pool's strings are not escaped properly

 */

public class T8038414 {

    private static final String NEW_LINE = System.getProperty("line.separator");

    private static final String TEST_CLASSES = System.getProperty("test.classes", ".");

    private static final String GOLDEN_STRING = escapeString(Test.test);

    private static String escapeString(String s) {

        StringBuilder sb = new StringBuilder();

        for (int i = 0; i < s.length(); i++) {

            char c = s.charAt(i);

            switch (c) {

                case '\t':

                    sb.append('\\').append('t');

                    break;

                case '\n':

                    sb.append('\\').append('n');

                    break;

                case '\r':

                    sb.append('\\').append('r');

                    break;

                case '\b':

                    sb.append('\\').append('b');

                    break;

                case '\f':

                    sb.append('\\').append('f');

                    break;

                case '\"':

                    sb.append('\\').append('\"');

                    break;

                case '\'':

                    sb.append('\\').append('\'');

                    break;

                case '\\':

                    sb.append('\\').append('\\');

                    break;

                default:

                    sb.append(c);

            }

        }

        return sb.toString();

    }

    public static void main(String... args) {

        new T8038414().run();

    }

    public void run() {

        String output = javap(Test.class.getName());

        List<String> actualValues = extractEscapedComments(output);

        for (String a : actualValues) {

            check(!GOLDEN_STRING.equals(a), String.format("Expected: %s, got: %s", GOLDEN_STRING, a));

        }

    }

    private List<String> extractConstantPool(String output) {

        List<String> cp = new ArrayList<>();

        boolean inCp = false;

        for (String s : output.split("\n")) {

            if (s.equals("{")) {

                break;

            }

            if (inCp) {

                cp.add(s);

            }

            if (s.equals("Constant pool:")) {

                inCp = true;

            }

        }

        return cp;

    }

    /**

     * Returns a list which contains comments of the string entry in the constant pool

     * and the appropriate UTF-8 value.

     *

     * @return a list

     */

    private List<String> extractEscapedComments(String output) {

        List<String> result = new ArrayList<>();

        Pattern stringPattern = Pattern.compile(" +#\\d+ = String +#(\\d+) +// +(.*)");

        int index = -1;

        List<String> cp = extractConstantPool(output);

        for (String c : cp) {

            Matcher matcher = stringPattern.matcher(c);

            if (matcher.matches()) {

                index = Integer.parseInt(matcher.group(1)) - 1;

                result.add(matcher.group(2));

                // only one String entry

                break;

            }

        }

        check(index == -1, "Escaped string is not found in constant pool");

        result.add(cp.get(index).replaceAll(".* +", "")); // remove #16 = Utf8

        return result;

    }

    private String javap(String className) {

        StringWriter sw = new StringWriter();

        PrintWriter out = new PrintWriter(sw);

        int rc = com.sun.tools.javap.Main.run(new String[]{"-v", "-classpath", TEST_CLASSES, className}, out);

        out.close();

        String output = sw.toString();

        System.err.println("class " + className);

        System.err.println(output);

        check(rc != 0, "javap failed. rc=" + rc);

        return output.replaceAll(NEW_LINE, "\n");

    }

    private void check(boolean cond, String msg) {

        if (cond) {

            throw new RuntimeException(msg);

        }

    }

    static class Test {

        static String test = "\\t\t\b\r\n\f\"\'\\";

    }

}