/*

  * #%L

  * JavaHg

  * %%

  * Copyright (C) 2011 aragost Trifork ag

  * %%

  * Permission is hereby granted, free of charge, to any person obtaining a copy

  * of this software and associated documentation files (the "Software"), to deal

  * in the Software without restriction, including without limitation the rights

  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell

  * copies of the Software, and to permit persons to whom the Software is

  * furnished to do so, subject to the following conditions:

  * 

  * The above copyright notice and this permission notice shall be included in

  * all copies or substantial portions of the Software.

  * 

  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR

  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,

  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE

  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER

  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,

  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN

  * THE SOFTWARE.

  * #L%

  */

 package com.aragost.javahg.internals;

 import java.io.ByteArrayInputStream;

 import java.io.ByteArrayOutputStream;

 import java.io.IOException;

 import java.util.Collections;

 import java.util.List;

 import com.aragost.javahg.Changeset;

 import com.aragost.javahg.Repository;

 import com.aragost.javahg.commands.ExecutionException;

 import com.aragost.javahg.commands.LogCommand;

 import com.google.common.collect.Lists;

 import com.google.common.io.ByteStreams;

 public class PullPushHelper {

     private static final byte[] BEGIN = "list of changesets:\n".getBytes();

     private static final byte[] BEGIN_FALLBACK = "adding changesets\n"

             .getBytes();

     private static final byte[] LINE_BEGIN = "add changeset ".getBytes();

     private static final byte[] REMOTE_ERROR = "remote: error: ".getBytes();

     public static List<Changeset> parseStream(AbstractCommand command,

             HgInputStream stream) throws IOException {

             Repository repo = command.getRepository();

         List<Changeset> result;

         // Pulling locally the full nodes are written after

         // "list of changesets:"

         // Over HTTP this isn't written.

         // In either case 12 character node prefixes are printed after

         // "adding changesets".

         // If possible use first case, otherwise fall back to node prefixes.

         // Make a copy

         ByteArrayOutputStream bos = new ByteArrayOutputStream();

         ByteStreams.copy(stream, bos);

         stream.consumeAll();

         stream = new HgInputStream(new ByteArrayInputStream(bos.toByteArray()), repo.newDecoder());

         if (stream.find(BEGIN)) {

             result = Lists.newArrayList();

             while (!stream.isEof() && !stream.match(BEGIN_FALLBACK)) {

                 result.add(repo.changeset(stream.textUpTo('\n')));

             }

         } else {

             stream = new HgInputStream(new ByteArrayInputStream(bos.toByteArray()), repo.newDecoder());

             List<String> nodePrefixes = Lists.newArrayList();

             if (stream.find(BEGIN_FALLBACK)) {

                 if (stream.find(LINE_BEGIN)) {

                     // 12 Character node prefix

                     nodePrefixes.add(stream.textUpTo('\n'));

                 }

             }

             if (nodePrefixes.isEmpty()) {

                 result = Collections.emptyList();

             } else {

                 result = LogCommand

                         .on(repo)

                         .rev(nodePrefixes.toArray(new String[nodePrefixes

                                 .size()])).execute();

             }

         }

         stream = new HgInputStream(new ByteArrayInputStream(bos.toByteArray()), repo.newDecoder());

         if (stream.find(REMOTE_ERROR)) {

             throw new ExecutionException(command, stream.textUpTo('\n'));

         }

         return result;

     }

 }