// Copyright (C) 2009 The Android Open Source Project
//
// 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 com.google.gerrit.server.mail;

import com.google.gerrit.common.errors.EmailException;
import com.google.gerrit.reviewdb.client.AccountProjectWatch.NotifyType;
import com.google.gerrit.reviewdb.client.Change;
import com.google.gerrit.reviewdb.client.Patch;
import com.google.gerrit.reviewdb.client.PatchLineComment;
import com.google.gerrit.server.change.PostReview.NotifyHandling;
import com.google.gerrit.server.patch.PatchFile;
import com.google.gerrit.server.patch.PatchList;
import com.google.gerrit.server.patch.PatchListNotAvailableException;
import com.google.inject.Inject;
import com.google.inject.assistedinject.Assisted;

import org.eclipse.jgit.lib.Repository;

import java.io.IOException;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Set;

/** Send comments, after the author of them hit used Publish Comments in the UI. */
public class CommentSender extends ReplyToChangeSender {
  public static interface Factory {
    public CommentSender create(NotifyHandling notify, Change change);
  }

  private final NotifyHandling notify;
  private List<PatchLineComment> inlineComments = Collections.emptyList();

  @Inject
  public CommentSender(EmailArguments ea,
      @Assisted NotifyHandling notify,
      @Assisted Change c) {
    super(ea, c, "comment");
    this.notify = notify;
  }

  public void setPatchLineComments(final List<PatchLineComment> plc) {
    inlineComments = plc;

    Set<String> paths = new HashSet<String>();
    for (PatchLineComment c : plc) {
      Patch.Key p = c.getKey().getParentKey();
      if (!Patch.COMMIT_MSG.equals(p.getFileName())) {
        paths.add(p.getFileName());
      }
    }
    String[] names = paths.toArray(new String[paths.size()]);
    Arrays.sort(names);
    changeData.setCurrentFilePaths(names);
  }

  @Override
  protected void init() throws EmailException {
    super.init();

    if (notify.compareTo(NotifyHandling.OWNER_REVIEWERS) >= 0) {
      ccAllApprovals();
    }
    if (notify.compareTo(NotifyHandling.ALL) >= 0) {
      bccStarredBy();
      includeWatchers(NotifyType.ALL_COMMENTS);
    }
  }

  @Override
  public void formatChange() throws EmailException {
    appendText(velocifyFile("Comment.vm"));
  }

  @Override
  public void formatFooter() throws EmailException {
    appendText(velocifyFile("CommentFooter.vm"));
  }

  public boolean hasInlineComments() {
    return !inlineComments.isEmpty();
  }

  public String getInlineComments() {
    return getInlineComments(1);
  }

  public String getInlineComments(int lines) {
    StringBuilder  cmts = new StringBuilder();

    final Repository repo = getRepository();
    try {
      PatchList patchList = null;
      if (repo != null) {
        try {
          patchList = getPatchList();
        } catch (PatchListNotAvailableException e) {
          patchList = null;
        }
      }

      Patch.Key currentFileKey = null;
      PatchFile currentFileData = null;
      for (final PatchLineComment c : inlineComments) {
        final Patch.Key pk = c.getKey().getParentKey();
        final int lineNbr = c.getLine();
        final short side = c.getSide();

        if (!pk.equals(currentFileKey)) {
          cmts.append("....................................................\n");
          if (Patch.COMMIT_MSG.equals(pk.get())) {
            cmts.append("Commit Message\n");
          } else {
            cmts.append("File ");
            cmts.append(pk.get());
            cmts.append("\n");
          }
          currentFileKey = pk;

          if (patchList != null) {
            try {
              currentFileData =
                  new PatchFile(repo, patchList, pk.getFileName());
            } catch (IOException e) {
              // Don't quote the line if we can't load it.
            }
          } else {
            currentFileData = null;
          }
        }

        if (currentFileData != null) {
          int maxLines;
          try {
            maxLines = currentFileData.getLineCount(side);
          } catch (Throwable e) {
            maxLines = lineNbr;
          }

          final int startLine = Math.max(1, lineNbr - lines + 1);
          final int stopLine = Math.min(maxLines, lineNbr + lines);

          for (int line = startLine; line <= lineNbr; ++line) {
            appendFileLine(cmts, currentFileData, side, line);
          }

          cmts.append(c.getMessage().trim());
          cmts.append("\n");

          for (int line = lineNbr + 1; line < stopLine; ++line) {
            appendFileLine(cmts, currentFileData, side, line);
          }
        }

        cmts.append("\n\n");
      }
    } finally {
      if (repo != null) {
        repo.close();
      }
    }
    return cmts.toString();
  }

  private void appendFileLine(StringBuilder cmts, PatchFile fileData, short side, int line) {
    cmts.append("Line " + line);
    try {
      final String lineStr = fileData.getLine(side, line);
      cmts.append(": ");
      cmts.append(lineStr);
    } catch (Throwable e) {
      // Don't quote the line if we can't safely convert it.
    }
    cmts.append("\n");
  }

  private Repository getRepository() {
    try {
      return args.server.openRepository(projectState.getProject().getNameKey());
    } catch (IOException e) {
      return null;
    }
  }
}