// Copyright (C) 2016 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.notedb;

import com.google.common.collect.ImmutableMap;
import com.google.gerrit.entities.Comment;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import org.eclipse.jgit.errors.ConfigInvalidException;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.ObjectReader;
import org.eclipse.jgit.notes.Note;
import org.eclipse.jgit.notes.NoteMap;

/**
 * A utility class that parses a NoteMap into commit => comment list data.
 *
 * @param <T> the RevisionNote for the comment type.
 */
class RevisionNoteMap<T extends RevisionNote<? extends Comment>> {
  // CommitID => blob ID
  final NoteMap noteMap;

  // CommitID => parsed data, immutable map.
  final ImmutableMap<ObjectId, T> revisionNotes;

  static RevisionNoteMap<ChangeRevisionNote> parse(
      ChangeNoteJson noteJson, ObjectReader reader, NoteMap noteMap, Comment.Status status)
      throws ConfigInvalidException, IOException {
    Map<ObjectId, ChangeRevisionNote> result = new HashMap<>();
    for (Note note : noteMap) {
      ChangeRevisionNote rn = new ChangeRevisionNote(noteJson, reader, note.getData(), status);
      rn.parse();

      result.put(note.copy(), rn);
    }
    return new RevisionNoteMap<>(noteMap, ImmutableMap.copyOf(result));
  }

  static RevisionNoteMap<RobotCommentsRevisionNote> parseRobotComments(
      ChangeNoteJson changeNoteJson, ObjectReader reader, NoteMap noteMap)
      throws ConfigInvalidException, IOException {
    Map<ObjectId, RobotCommentsRevisionNote> result = new HashMap<>();
    for (Note note : noteMap) {
      RobotCommentsRevisionNote rn =
          new RobotCommentsRevisionNote(changeNoteJson, reader, note.getData());
      rn.parse();
      result.put(note.copy(), rn);
    }
    return new RevisionNoteMap<>(noteMap, ImmutableMap.copyOf(result));
  }

  static <T extends RevisionNote<? extends Comment>> RevisionNoteMap<T> emptyMap() {
    return new RevisionNoteMap<>(NoteMap.newEmptyMap(), ImmutableMap.of());
  }

  private RevisionNoteMap(NoteMap noteMap, ImmutableMap<ObjectId, T> revisionNotes) {
    this.noteMap = noteMap;
    this.revisionNotes = revisionNotes;
  }
}

@@ -766,56 +766,8 @@
 on;%0A
-import java.util.HashMap;%0Aimport java.util.Map;%0A
 impo
@@ -1178,25 +1178,26 @@
 ment%3E%3E %7B%0A  /
-/
+**
  CommitID =%3E
@@ -1204,16 +1204,19 @@
  blob ID
+ */
 %0A  final
@@ -1237,17 +1237,18 @@
 ap;%0A%0A  /
-/
+**
  CommitI
@@ -1267,73 +1267,219 @@
 data
-, immutable map.%0A  final ImmutableMap%3CObjectId, T%3E revisionNotes;
+ */%0A  final ImmutableMap%3CObjectId, T%3E revisionNotes;%0A%0A  private RevisionNoteMap(NoteMap noteMap, ImmutableMap%3CObjectId, T%3E revisionNotes) %7B%0A    this.noteMap = noteMap;%0A    this.revisionNotes = revisionNotes;%0A  %7D
 %0A%0A  
@@ -1667,35 +1667,52 @@
 Exception %7B%0A    
-Map
+ImmutableMap.Builder
 %3CObjectId, Chang
@@ -1731,37 +1731,44 @@
 e%3E result = 
-new HashMap%3C%3E
+ImmutableMap.builder
 ();%0A    for 
@@ -1993,34 +1993,21 @@
 ap, 
-ImmutableMap.copyOf(result
+result.build(
 ));%0A
@@ -2213,19 +2213,36 @@
 n %7B%0A    
-Map
+ImmutableMap.Builder
 %3CObjectI
@@ -2284,21 +2284,28 @@
 t = 
-new HashMap%3C%3E
+ImmutableMap.builder
 ();%0A
@@ -2559,34 +2559,21 @@
 ap, 
-ImmutableMap.copyOf(result
+result.build(
 ));%0A
@@ -2745,166 +2745,7 @@
 %0A  %7D
-%0A%0A  private RevisionNoteMap(NoteMap noteMap, ImmutableMap%3CObjectId, T%3E revisionNotes) %7B%0A    this.noteMap = noteMap;%0A    this.revisionNotes = revisionNotes;%0A  %7D
 %0A%7D%0A

Improve readability, build ImmutableMap directly