// 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.sshd;

import com.google.common.base.Function;
import com.google.common.base.Optional;
import com.google.common.base.Predicates;
import com.google.common.collect.FluentIterable;
import com.google.gerrit.reviewdb.client.Change;
import com.google.gerrit.reviewdb.client.Project;
import com.google.gerrit.reviewdb.server.ReviewDb;
import com.google.gerrit.server.ChangeFinder;
import com.google.gerrit.server.CurrentUser;
import com.google.gerrit.server.change.ChangeResource;
import com.google.gerrit.server.change.ChangesCollection;
import com.google.gerrit.server.notedb.ChangeNotes;
import com.google.gerrit.server.project.ChangeControl;
import com.google.gerrit.server.project.NoSuchChangeException;
import com.google.gerrit.server.project.ProjectControl;
import com.google.gerrit.sshd.BaseCommand.UnloggedFailure;
import com.google.gwtorm.server.OrmException;
import com.google.inject.Inject;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Map;

public class ChangeArgumentParser {
  private final CurrentUser currentUser;
  private final ChangesCollection changesCollection;
  private final ChangeFinder changeFinder;
  private final ReviewDb db;
  private final ChangeNotes.Factory changeNotesFactory;
  private final ChangeControl.GenericFactory changeControlFactory;

  @Inject
  ChangeArgumentParser(CurrentUser currentUser,
      ChangesCollection changesCollection,
      ChangeFinder changeFinder,
      ReviewDb db,
      ChangeNotes.Factory changeNotesFactory,
      ChangeControl.GenericFactory changeControlFactory) {
    this.currentUser = currentUser;
    this.changesCollection = changesCollection;
    this.changeFinder = changeFinder;
    this.db = db;
    this.changeNotesFactory = changeNotesFactory;
    this.changeControlFactory = changeControlFactory;
  }

  public void addChange(String id, Map<Change.Id, ChangeResource> changes)
      throws UnloggedFailure, OrmException {
    addChange(id, changes, null);
  }

  public void addChange(String id, Map<Change.Id, ChangeResource> changes,
      ProjectControl projectControl) throws UnloggedFailure, OrmException {
    addChange(id, changes, projectControl, true);
  }

  public void addChange(String id, Map<Change.Id, ChangeResource> changes,
      ProjectControl projectControl, boolean useIndex) throws UnloggedFailure,
      OrmException {
    List<ChangeControl> matched =
        useIndex ?
            changeFinder.find(id, currentUser) :
            changeFromNotesFactory(id, currentUser);
    List<ChangeControl> toAdd = new ArrayList<>(changes.size());
    for (ChangeControl ctl : matched) {
      if (!changes.containsKey(ctl.getId())
          && inProject(projectControl, ctl.getProject())
          && ctl.isVisible(db)) {
        toAdd.add(ctl);
      }
    }

    if (toAdd.isEmpty()) {
      throw new UnloggedFailure(1, "\"" + id + "\" no such change");
    } else if (toAdd.size() > 1) {
      throw new UnloggedFailure(1, "\"" + id + "\" matches multiple changes");
    }
    ChangeControl ctl = toAdd.get(0);
    changes.put(ctl.getId(), changesCollection.parse(ctl));
  }

  private List<ChangeControl> changeFromNotesFactory(String id,
      final CurrentUser currentUser) throws OrmException {
    List<ChangeNotes> changes =
        changeNotesFactory.create(db, Arrays.asList(Change.Id.parse(id)));
    return FluentIterable.from(changes)
        .transform(new Function<ChangeNotes, ChangeControl>() {
          @Override
          public ChangeControl apply(ChangeNotes changeNote) {
            return controlForChange(changeNote, currentUser);
          }
        }).filter(Predicates.notNull()).toList();
  }

  private ChangeControl controlForChange(ChangeNotes change, CurrentUser user) {
    try {
      return changeControlFactory.controlFor(change, user);
    } catch (NoSuchChangeException e) {
      return null;
    }
  }

  private boolean inProject(ProjectControl projectControl, Project project) {
    if (projectControl != null) {
      return projectControl.getProject().getNameKey().equals(project.getNameKey());
    }

    // No --project option, so they want every project.
    return true;
  }
}
@@ -646,171 +646,51 @@
 ort 
-com.google.common.base.Function;%0Aimport com.google.common.base.Optional;%0Aimport com.google.common.base.Predicates;%0Aimport com.google.common.collect.FluentIterable;
+static java.util.stream.Collectors.toList;%0A
 %0Aimp
@@ -1502,16 +1502,43 @@
 til.Map;
+%0Aimport java.util.Optional;
 %0A%0Apublic
@@ -3724,20 +3724,8 @@
  id,
-%0A      final
  Cur
@@ -3745,16 +3745,22 @@
 entUser)
+%0A     
  throws 
@@ -3782,43 +3782,14 @@
     
-List%3CChangeNotes%3E changes =%0A       
+return
  cha
@@ -3854,83 +3854,72 @@
 d)))
-;
 %0A    
-return FluentIterable.from(changes)%0A        .transform(new Function%3CC
+    .stream()%0A        .map(changeNote -%3E controlForChange(c
 hang
@@ -3927,235 +3927,160 @@
 Note
-s
 , 
-ChangeControl%3E() %7B%0A          @Override%0A          public ChangeControl apply(ChangeNotes changeNote) %7B%0A            return controlForChange(changeNote, currentUser);%0A          %7D%0A        %7D).filter(Predicates.notNull()).
+currentUser))%0A        .filter(changeControl -%3E changeControl.isPresent())%0A        .map(changeControl -%3E changeControl.get())%0A        .collect(
 toList()
 ;%0A  
@@ -4075,16 +4075,17 @@
 toList()
+)
 ;%0A  %7D%0A%0A 
@@ -4093,16 +4093,25 @@
 private 
+Optional%3C
 ChangeCo
@@ -4115,16 +4115,17 @@
 eControl
+%3E
  control
@@ -4193,24 +4193,36 @@
      return 
+Optional.of(
 changeContro
@@ -4250,24 +4250,25 @@
 hange, user)
+)
 ;%0A    %7D catc
@@ -4310,20 +4310,32 @@
  return 
-null
+Optional.empty()
 ;%0A    %7D%0A

Replace FluentIterable with Java 8 stream