/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * See LICENSE.txt included in this distribution for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at LICENSE.txt.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright (c) 2008, 2011, Oracle and/or its affiliates. All rights reserved.
 */
package org.opensolaris.opengrok.history;

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.Reader;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.opensolaris.opengrok.configuration.Configuration;
import org.opensolaris.opengrok.util.Executor;
import org.opensolaris.opengrok.util.IOUtils;

/**
 * Access to a Bazaar repository.
 */
public class BazaarRepository extends Repository {
    private static final Logger logger = Logger.getLogger(BazaarRepository.class.getName());
    private static final long serialVersionUID = 1L;
    /** The property name used to obtain the client command for thisrepository. */
    public static final String CMD_PROPERTY_KEY =
        Configuration.PROPERTY_KEY_PREFIX + "history.Bazaar";
    /** The command to use to access the repository if none was given explicitly */
    public static final String CMD_FALLBACK = "bzr";

    /**
     * Create a new instance of type {@code Bazaar}.
     */
    public BazaarRepository() {
        type = "Bazaar";
        datePattern = "EEE yyyy-MM-dd hh:mm:ss ZZZZ";
    }

   /**
     * Get an executor to be used for retrieving the history log for the
     * named file.
     *
     * @param file The file to retrieve history for (canonical path incl. source
     *  root)
     * @return An Executor ready to be started
     */
    Executor getHistoryLogExecutor(final File file, final String sinceRevision)
        throws IOException
    {
        String abs = file.getCanonicalPath();
        String filename = "";
        if (abs.length() > directoryName.length()) {
            filename = abs.substring(directoryName.length() + 1);
        }

        List<String> cmd = new ArrayList<String>();
        ensureCommand(CMD_PROPERTY_KEY, CMD_FALLBACK);
        cmd.add(this.cmd);
        cmd.add("log");

        if (file.isDirectory()) {
           cmd.add("-v");
       }
       cmd.add(filename);

       if (sinceRevision != null) {
           cmd.add("-r");
           cmd.add(sinceRevision + "..-1");
       }

       return new Executor(cmd, new File(getDirectoryName()));
    }

    /**
     * {@inheritDoc}
     */
    @SuppressWarnings("resource")
    @Override
    public InputStream getHistoryGet(String parent, String basename, String rev)
    {
        InputStream ret = null;
        File directory = new File(directoryName);

        Process process = null;
        InputStream in = null;
        try {
            String filename =  (new File(parent, basename)).getCanonicalPath()
                .substring(directoryName.length() + 1);
            ensureCommand(CMD_PROPERTY_KEY, CMD_FALLBACK);
            String argv[] = {cmd, "cat", "-r", rev, filename};
            process = Runtime.getRuntime().exec(argv, null, directory);

            ByteArrayOutputStream out = new ByteArrayOutputStream();
            byte[] buffer = new byte[32 * 1024];
            in = process.getInputStream();
            int len;

            while ((len = in.read(buffer)) != -1) {
                if (len > 0) {
                    out.write(buffer, 0, len);
                }
            }

            ret = new ByteArrayInputStream(out.toByteArray());
        } catch (Exception exp) {
            logger.warning("Failed to get history for '" + parent 
                + File.separator + basename + "': " + exp.getMessage());
            logger.log(Level.FINE, "getHistoryGet", exp);
        } finally {
            // Clean up zombie-processes...
            if (process != null) {
                try {
                    process.exitValue();
                } catch (IllegalThreadStateException exp) {
                    // the process is still running??? just kill it..
                    process.destroy();
                }
            }
            IOUtils.close(in);
        }

        return ret;
    }

    /** Pattern used to extract author/revision from bzr blame. */
    private static final Pattern BLAME_PATTERN =
        Pattern.compile("^\\W*(\\S+)\\W+(\\S+).*$");

    /**
     * Annotate the specified file/revision.
     *
     * @param file file to annotate
     * @param revision revision to annotate
     * @return file annotation
     */
    @Override
    public Annotation annotate(File file, String revision) throws IOException {
        List<String> cmd = new ArrayList<String>();
        ensureCommand(CMD_PROPERTY_KEY, CMD_FALLBACK);
        cmd.add(this.cmd);
        cmd.add("blame");
        cmd.add("--all");
        cmd.add("--long");
        if (revision != null) {
            cmd.add("-r");
            cmd.add(revision);
        }
        cmd.add(file.getName());

        Executor exec = new Executor(cmd, file.getParentFile());
        int status = exec.exec();

        if (status != 0) {
            logger.warning("Failed to get annotations for '"
                + file.getAbsolutePath() + "' - Exit code " + status);
        }

        return parseAnnotation(exec.getOutputReader(), file.getName());
    }

    @SuppressWarnings({ "javadoc", "static-method" })
    protected Annotation parseAnnotation(Reader input, String fileName)
        throws IOException
    {
        BufferedReader in = new BufferedReader(input);
        Annotation ret = new Annotation(fileName);
        String line = "";
        int lineno = 0;
        Matcher matcher = BLAME_PATTERN.matcher(line);
        while ((line = in.readLine()) != null) {
            ++lineno;
            matcher.reset(line);
            if (matcher.find()) {
                String rev = matcher.group(1);
                String author = matcher.group(2).trim();
                ret.addLine(rev, author);
            } else {
                logger.log(Level.WARNING,
                    "Did not find annotation in line {0} [{1}]",
                    new Object[]{String.valueOf(lineno), line});
            }
        }
        return ret;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean fileHasAnnotation(File file) {
        return true;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void update() throws IOException {
        File directory = new File(getDirectoryName());

        List<String> cmd = new ArrayList<String>();
        ensureCommand(CMD_PROPERTY_KEY, CMD_FALLBACK);
        cmd.add(this.cmd);
        cmd.add("info");
        Executor executor = new Executor(cmd, directory);
        if (executor.exec() != 0) {
            throw new IOException(executor.getErrorString());
        }

        if (executor.getOutputString().indexOf("parent branch:") != -1) {
            cmd.clear();
            cmd.add(this.cmd);
            cmd.add("up");
            executor = new Executor(cmd, directory);
            if (executor.exec() != 0) {
                throw new IOException(executor.getErrorString());
            }
        }
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean fileHasHistory(File file) {
        // Todo: is there a cheap test for whether Bazaar has history
        // available for a file?
        // Otherwise, this is harmless, since Bazaar's commands will just
        // print nothing if there is no history.
        return true;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean isRepositoryFor(File file) {
        if (file.isDirectory()) {
            File f = new File(file, ".bzr");
            return f.exists() && f.isDirectory();
        }
        return false;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean isWorking() {
        if (working == null) {
            ensureCommand(CMD_PROPERTY_KEY, CMD_FALLBACK);
            working = checkCmd(cmd, "--help");
        }
        return working.booleanValue();
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public boolean hasHistoryForDirectories() {
        return true;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public History getHistory(File file, String sinceRevision)
        throws HistoryException
    {
        return new BazaarHistoryParser(this).parse(file, sinceRevision);
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public History getHistory(File file) throws HistoryException {
        return getHistory(file, null);
    }
}