/*
 * Copyright 2000-2014 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package jetbrains.buildServer.buildTriggers.vcs.mercurial;

import jetbrains.buildServer.agent.AgentRunningBuild;
import jetbrains.buildServer.agent.BuildProgressLogger;
import jetbrains.buildServer.agent.vcs.IncludeRuleUpdater;
import jetbrains.buildServer.buildTriggers.vcs.mercurial.command.AuthSettings;
import jetbrains.buildServer.buildTriggers.vcs.mercurial.command.HgVcsRoot;
import jetbrains.buildServer.buildTriggers.vcs.mercurial.command.exception.UnrelatedRepositoryException;
import jetbrains.buildServer.buildTriggers.vcs.mercurial.command.exception.WrongSubrepoUrlException;
import jetbrains.buildServer.buildTriggers.vcs.mercurial.ext.BeforeWorkingDirUpdateExtension;
import jetbrains.buildServer.buildTriggers.vcs.mercurial.ext.MercurialExtension;
import jetbrains.buildServer.log.Loggers;
import jetbrains.buildServer.util.FileUtil;
import jetbrains.buildServer.vcs.IncludeRule;
import jetbrains.buildServer.vcs.VcsException;
import jetbrains.buildServer.vcs.VcsRoot;
import org.jetbrains.annotations.NotNull;

import java.io.File;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import static com.intellij.openapi.util.io.FileUtil.delete;

/**
 * @author dmitry.neverov
 */
public class MercurialIncludeRuleUpdater implements IncludeRuleUpdater {

  protected final MirrorManager myMirrorManager;
  protected final AgentRepoFactory myRepoFactory;
  protected final HgVcsRoot myRoot;
  private final AuthSettings myAuthSettings;
  private final String myToVersion;
  private final BuildProgressLogger myLogger;
  private final boolean myUseLocalMirrors;
  private int myPullTimeout;
  private final boolean myUseTraceback;
  private final boolean myProfile;
  private final List<MercurialExtension> myExtensions = new ArrayList<MercurialExtension>();
  protected final MercurialProgress myProgress;

  public MercurialIncludeRuleUpdater(@NotNull AgentPluginConfig pluginConfig,
                                     @NotNull MirrorManager mirrorManager,
                                     @NotNull AgentRepoFactory repoFactory,
                                     @NotNull VcsRoot root,
                                     @NotNull String toVersion,
                                     @NotNull AgentRunningBuild build) {
    myMirrorManager = mirrorManager;
    myRepoFactory = repoFactory;
    myRoot = new HgVcsRoot(root);
    myAuthSettings = myRoot.getAuthSettings();
    myToVersion = toVersion;
    myLogger = build.getBuildLogger();
    myUseLocalMirrors = pluginConfig.isUseLocalMirrors(build);
    myPullTimeout = pluginConfig.getPullTimeout(build);
    myUseTraceback = pluginConfig.runWithTraceback(build);
    myProfile = pluginConfig.runWithProfile(build);
    myProgress = new MercurialBuildLogProgress(build.getBuildLogger());
  }


  public void process(@NotNull IncludeRule rule, @NotNull File workingDir) throws VcsException {
    try {
      checkRuleIsValid(rule);
      if (myUseLocalMirrors)
        updateLocalMirror(myRoot.getRepository(), myToVersion);
      updateRepository(workingDir);
      updateWorkingDir(workingDir, myToVersion, myRoot.getRepository());
    } catch (Exception e) {
      throwVcsException(e);
    }
  }


  public void dispose() throws VcsException {
  }


  public void registerExtension(@NotNull MercurialExtension extention) {
    myExtensions.add(extention);
  }


  @NotNull
  protected <T extends MercurialExtension> List<T> getExtensions(@NotNull Class<T> extensionClass) {
    List<T> extentions = new ArrayList<T>();
    for (MercurialExtension e : myExtensions) {
      if (extensionClass.isInstance(e))
        extentions.add(extensionClass.cast(e));
    }
    return extentions;
  }


  protected void updateLocalMirror(@NotNull String repositoryUrl, @NotNull String revision) throws VcsException, IOException {
    File mirrorDir = myMirrorManager.getMirrorDir(repositoryUrl);
    HgRepo mirrorRepo = myRepoFactory.createRepo(myRoot, mirrorDir, myProgress);
    if (!mirrorRepo.isValidRepository()) {
      delete(mirrorDir);
      mirrorRepo.init().call();
    }
    mirrorRepo.setDefaultPath(myRoot.getRepository());
    mirrorRepo.setTeamCityConfig(myRoot.getCustomHgConfig());
    myLogger.message("Update local mirror of " + myAuthSettings.getRepositoryUrlWithHiddenPassword(repositoryUrl) + " at " + mirrorDir);
    if (mirrorRepo.containsRevision(revision)) {
      myLogger.message("Local mirror is already up-to-date");
    } else {
      myLogger.message("Start pulling changes from " + myAuthSettings.getRepositoryUrlWithHiddenPassword(repositoryUrl));
      mirrorRepo.pull().fromRepository(repositoryUrl)
              .withTraceback(myUseTraceback)
              .withProfile(myProfile)
              .withTimeout(myPullTimeout)
              .call();
      myLogger.message("Local mirror changes successfully pulled");
    }
  }


  protected void updateRepository(@NotNull File workingDir) throws VcsException, IOException {
    String repositoryUrl = getDefaultPullUrl(myRoot, myUseLocalMirrors);
    HgRepo repo = myRepoFactory.createRepo(myRoot, workingDir, myProgress);
    myLogger.message("Update repository " + workingDir.getAbsolutePath());
    disableSharing(workingDir);
    if (!repo.isValidRepository())
      repo.init().call();
    repo.setDefaultPath(myRoot.getRepository());
    repo.setTeamCityConfig(myRoot.getCustomHgConfig());
    if (repo.containsRevision(myToVersion)) {
      myLogger.message("Repository already contains revision " + myToVersion);
    } else {
      myLogger.message("Start pulling changes from " + (myUseLocalMirrors ? "local mirror " : "") + myAuthSettings.getRepositoryUrlWithHiddenPassword(repositoryUrl));
      try {
        repo.pull().fromRepository(repositoryUrl)
                .withTraceback(myUseTraceback)
                .withProfile(myProfile)
                .withTimeout(myPullTimeout)
                .call();
      } catch (UnrelatedRepositoryException e) {
        throw new UnrelatedRepositoryException(myAuthSettings.getRepositoryUrlWithHiddenPassword(repositoryUrl), workingDir);
      }
      myLogger.message("Changes successfully pulled");
    }
  }


  private void disableSharing(@NotNull File workingDir) {
    File dotHg = new File(workingDir, ".hg");
    File sharedpath = new File(dotHg, "sharedpath");
    if (sharedpath.exists())
      FileUtil.delete(sharedpath);
  }


  private void updateWorkingDir(@NotNull File workingDir, @NotNull String toVersion, @NotNull String repositoryUrl) throws VcsException, IOException {
    HgRepo repo = myRepoFactory.createRepo(myRoot, workingDir, myProgress);
    List<File> repos = new ArrayList<File>();
    updateSubrepositories(repo, toVersion, repositoryUrl, repos);
    doUpdateWorkingDir(repo, toVersion);
    purge(repos);
  }

  private void purge(@NotNull List<File> dirs) throws VcsException {
    HgVcsRoot.PurgePolicy purgePolicy = myRoot.getPurgePolicy();
    if (purgePolicy == HgVcsRoot.PurgePolicy.DONT_RUN)
      return;
    for (File dir : dirs) {
      myLogger.message("Run purge in " + dir.getAbsolutePath());
      HgRepo repo = myRepoFactory.createRepo(myRoot, dir, myProgress);
      repo.purge().withPolicy(purgePolicy).call();
      myLogger.message("Purge in " + dir.getAbsolutePath() + " is finished");
    }
  }

  private void updateSubrepositories(@NotNull HgRepo repo,
                                     @NotNull String toVersion,
                                     @NotNull String parentRepositoryUrl,
                                     @NotNull List<File> repoAccumulator) throws VcsException, IOException {
    repoAccumulator.add(repo.getWorkingDir());
    if (!repo.hasSubreposAtRevision(toVersion))
      return;
    myLogger.message("Process subrepos of " + parentRepositoryUrl);
    String workingDirRevision = repo.getWorkingDirRevision();
    Map<String, SubRepo> workingDirSubrepos = repo.getSubrepositories(workingDirRevision);
    Map<String, SubRepo> subrepos = repo.getSubrepositories(toVersion);
    for (Map.Entry<String, SubRepo> entry : subrepos.entrySet()) {
      String path = entry.getKey();
      SubRepo subrepoConfig = entry.getValue();
      myLogger.message("Process subrepoConfig at path " + path + " (url: " + subrepoConfig.url() + ")");
      SubRepo workingDirSubrepo = workingDirSubrepos.get(path);
      if (workingDirSubrepo != null && subrepoConfig.hasDifferentUrlThan(workingDirSubrepo)) {
        myLogger.message("The url of subrepoConfig was changed between revisions " + workingDirRevision + " and " + toVersion + " , delete the subrepoConfig");
        delete(subrepoConfigDir(repo, subrepoConfig));
      }
      HgRepo subrepository = myRepoFactory.createRepo(myRoot, subrepoConfigDir(repo, subrepoConfig), myProgress);
      String subrepoUrl;
      try {
        subrepoUrl = subrepoConfig.resolveUrl(parentRepositoryUrl);
        if (myUseLocalMirrors && subrepoConfig.vcsType() == SubRepo.VcsType.hg && !isRelativeUrl(subrepoUrl))
          syncSubrepo(subrepository, subrepoUrl, subrepoConfig.revision());
      } catch (WrongSubrepoUrlException e) {
        myLogger.warning("Failed to resolve subrepo url '" + subrepoConfig.url() + "': " + e.getMessage());
        Loggers.VCS.warn("Failed to resolve subrepo url '" + subrepoConfig.url() + "'", e);
        subrepoUrl = subrepoConfig.url();
      }
      updateSubrepositories(subrepository, subrepoConfig.revision(), subrepoUrl, repoAccumulator);
    }
  }

  private boolean isRelativeUrl(@NotNull String url) {
    return url.startsWith(".");
  }

  protected void syncSubrepo(@NotNull HgRepo subrepository, @NotNull String subrepoUrl, @NotNull String subrepoRevision) throws VcsException, IOException {
    disableSharing(subrepository.getWorkingDir());
    if (!subrepository.isValidRepository() || !subrepository.containsRevision(subrepoRevision)) {
      updateLocalMirror(subrepoUrl, subrepoRevision);
      File mirrorDir = myMirrorManager.getMirrorDir(subrepoUrl);
      if (!subrepository.isValidRepository())
        subrepository.init().call();
      subrepository.setDefaultPath(subrepoUrl);
      subrepository.setTeamCityConfig(myRoot.getCustomHgConfig());
      myLogger.message("Pull from local mirror");
      subrepository.pull().fromRepository(mirrorDir)
              .withTraceback(myUseTraceback)
              .withProfile(myProfile)
              .withTimeout(myPullTimeout)
              .call();
      myLogger.message("done");
    }
  }


  private void doUpdateWorkingDir(@NotNull HgRepo repo, @NotNull String revision) throws VcsException {
    for (BeforeWorkingDirUpdateExtension e : getExtensions(BeforeWorkingDirUpdateExtension.class)) {
      e.call(repo, revision);
    }
    myLogger.message("Updating working dir " + repo.path() + " to revision " + revision);
    repo.update().withTraceback(myUseTraceback).toRevision(revision).call();
    myLogger.message("Working dir updated");
  }


  protected String getDefaultPullUrl(HgVcsRoot root, boolean useLocalMirror) throws IOException {
    if (useLocalMirror) {
      File mirrorDir = myMirrorManager.getMirrorDir(root.getRepository());
      return mirrorDir.getCanonicalPath();
    } else {
      return root.getRepository();
    }
  }


  private void checkRuleIsValid(IncludeRule includeRule) throws VcsException {
    if (includeRule.getTo() != null && includeRule.getTo().length() > 0) {
      if (!".".equals(includeRule.getFrom()) && includeRule.getFrom().length() != 0)
        throw new VcsException("Invalid include rule: " + includeRule.toString() + ", Mercurial plugin supports mapping of the form: +:.=>dir only.");
    }
  }


  private void throwVcsException(Exception e) throws VcsException {
    if (e instanceof VcsException)
      throw (VcsException) e;
    else
      throw new VcsException(e);
  }

  private File subrepoConfigDir(@NotNull HgRepo parentRepo, @NotNull SubRepo subrepo) {
    return new File(parentRepo.getWorkingDir(), subrepo.path());
  }
}