/*

 * Copyright (c) 2010, 2012, 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.  Oracle designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Oracle in the LICENSE file that accompanied this code.

 *

 * 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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 */

package jdk.nashorn.internal.test.framework;

import java.io.BufferedReader;

import java.io.ByteArrayOutputStream;

import java.io.File;

import java.io.FileReader;

import java.io.IOException;

import java.io.PrintStream;

import java.io.Reader;

/**

 * Simple utilities to deal with build-dir, read/dump files etc.

 */

public abstract class TestHelper {

    public static final String TEST_ROOT   = "test";

    public static final String BUILD_ROOT  = "build/test";

    public static final String TEST_PREFIX = TEST_ROOT + File.separator;

    private TestHelper() {

        // empty

    }

    protected static File makeBuildDir(final File testFile) {

        final File buildDir = getBuildDir(testFile);

        if (!new File(BUILD_ROOT).exists()) {

            throw new IllegalArgumentException("no " + BUILD_ROOT + " directory in " + new File(".").getAbsolutePath());

        }

        buildDir.mkdirs();

        return buildDir;

    }

    protected static File getBuildDir(final File testFile) {

        if (!testFile.getPath().startsWith(TEST_PREFIX)) {

            throw new IllegalArgumentException("test file path not a relative pathname");

        }

        final File buildDir = new File(BUILD_ROOT + File.separator + testFile.getParent().substring(TEST_PREFIX.length()));

        return buildDir;

    }

    // return the first line of the given file

    protected static String firstLine(final File file) throws IOException {

        return content(file, true);

    }

    // return the full content of the file as a String

    protected static String fullContent(final File file) throws IOException {

        return content(file, false);

    }

    private static String content(final File file, final boolean firstLine) throws IOException {

        final ByteArrayOutputStream bos = new ByteArrayOutputStream();

        final PrintStream ps = new PrintStream(bos);

        dumpFile(ps, file);

        final String contents = bos.toString();

        if (! firstLine) {

            return contents;

        }

        // else return only the first line, stripping the trailing cr, lf or cr+lf,

        // if present

        final int cr = contents.indexOf('\r');

        if (cr > 0) {

            return contents.substring(0, cr);

        }

        final int lf = contents.indexOf('\n');

        if (lf > 0) {

            return contents.substring(0, lf);

        }

        return contents;

    }

    // dump the content of given reader on standard output

    protected static void dumpFile(final Reader rdr) throws IOException {

        dumpFile(System.out, rdr);

    }

    // dump the content of given reader on given output stream

    protected static void dumpFile(final PrintStream output, final Reader rdr) throws IOException {

        try (BufferedReader reader = new BufferedReader(rdr)) {

            while (true) {

                final String line = reader.readLine();

                if (line == null) {

                    break;

                }

                output.println(line);

            }

        }

    }

    // dump the content of given file on standard output

    protected static void dumpFile(final File file) throws IOException {

        dumpFile(System.out, file);

    }

    // dump the content of given file on given output stream

    protected static void dumpFile(final PrintStream output, final File file) throws IOException {

        try (Reader rdr = new FileReader(file); BufferedReader reader = new BufferedReader(rdr)) {

            while (true) {

                final String line = reader.readLine();

                if (line == null) {

                    break;

                }

                output.println(line);

            }

        }

    }

}