// Copyright (C) 2013 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.acceptance.rest.change;

import static com.google.common.truth.Truth.assertThat;
import static com.google.gerrit.acceptance.GitUtil.checkout;

import com.google.common.collect.Iterables;
import com.google.gerrit.acceptance.PushOneCommit;
import com.google.gerrit.extensions.client.ChangeStatus;
import com.google.gerrit.extensions.client.ListChangesOption;
import com.google.gerrit.extensions.client.SubmitType;
import com.google.gerrit.extensions.common.ChangeInfo;

import org.eclipse.jgit.api.Git;
import org.eclipse.jgit.revwalk.RevCommit;
import org.junit.Test;

import java.util.List;

public class SubmitByCherryPickIT extends AbstractSubmit {

  @Override
  protected SubmitType getSubmitType() {
    return SubmitType.CHERRY_PICK;
  }

  @Test
  public void submitWithCherryPickIfFastForwardPossible() throws Exception {
    Git git = createProject();
    PushOneCommit.Result change = createChange(git);
    submit(change.getChangeId());
    assertCherryPick(git, false);
    assertThat(getRemoteHead().getParent(0))
      .isEqualTo(change.getCommit().getParent(0));
  }

  @Test
  public void submitWithCherryPick() throws Exception {
    Git git = createProject();
    RevCommit initialHead = getRemoteHead();
    PushOneCommit.Result change =
        createChange(git, "Change 1", "a.txt", "content");
    submit(change.getChangeId());

    RevCommit oldHead = getRemoteHead();
    checkout(git, initialHead.getId().getName());
    PushOneCommit.Result change2 =
        createChange(git, "Change 2", "b.txt", "other content");
    submit(change2.getChangeId());
    assertCherryPick(git, false);
    RevCommit newHead = getRemoteHead();
    assertThat(newHead.getParentCount()).isEqualTo(1);
    assertThat(newHead.getParent(0)).isEqualTo(oldHead);
    assertCurrentRevision(change2.getChangeId(), 2, newHead);
    assertSubmitter(change2.getChangeId(), 1);
    assertSubmitter(change2.getChangeId(), 2);
  }

  @Test
  public void submitWithContentMerge() throws Exception {
    Git git = createProject();
    setUseContentMerge();
    PushOneCommit.Result change =
        createChange(git, "Change 1", "a.txt", "aaa\nbbb\nccc\n");
    submit(change.getChangeId());
    PushOneCommit.Result change2 =
        createChange(git, "Change 2", "a.txt", "aaa\nbbb\nccc\nddd\n");
    submit(change2.getChangeId());

    RevCommit oldHead = getRemoteHead();
    checkout(git, change.getCommitId().getName());
    PushOneCommit.Result change3 =
        createChange(git, "Change 3", "a.txt", "bbb\nccc\n");
    submit(change3.getChangeId());
    assertCherryPick(git, true);
    RevCommit newHead = getRemoteHead();
    assertThat(newHead.getParent(0)).isEqualTo(oldHead);
    assertApproved(change3.getChangeId());
    assertCurrentRevision(change3.getChangeId(), 2, newHead);
    assertSubmitter(change2.getChangeId(), 1);
    assertSubmitter(change2.getChangeId(), 2);
  }

  @Test
  public void submitWithContentMerge_Conflict() throws Exception {
    Git git = createProject();
    setUseContentMerge();
    RevCommit initialHead = getRemoteHead();
    PushOneCommit.Result change =
        createChange(git, "Change 1", "a.txt", "content");
    submit(change.getChangeId());

    RevCommit oldHead = getRemoteHead();
    checkout(git, initialHead.getId().getName());
    PushOneCommit.Result change2 =
        createChange(git, "Change 2", "a.txt", "other content");
    submitWithConflict(change2.getChangeId());
    assertThat(getRemoteHead()).isEqualTo(oldHead);
    assertCurrentRevision(change2.getChangeId(), 1, change2.getCommitId());
    assertSubmitter(change2.getChangeId(), 1);
  }

  @Test
  public void submitOutOfOrder() throws Exception {
    Git git = createProject();
    RevCommit initialHead = getRemoteHead();
    PushOneCommit.Result change =
        createChange(git, "Change 1", "a.txt", "content");
    submit(change.getChangeId());

    RevCommit oldHead = getRemoteHead();
    checkout(git, initialHead.getId().getName());
    createChange(git, "Change 2", "b.txt", "other content");
    PushOneCommit.Result change3 =
        createChange(git, "Change 3", "c.txt", "different content");
    submit(change3.getChangeId());
    assertCherryPick(git, false);
    RevCommit newHead = getRemoteHead();
    assertThat(newHead.getParent(0)).isEqualTo(oldHead);
    assertApproved(change3.getChangeId());
    assertCurrentRevision(change3.getChangeId(), 2, newHead);
    assertSubmitter(change3.getChangeId(), 1);
    assertSubmitter(change3.getChangeId(), 2);
  }

  @Test
  public void submitOutOfOrder_Conflict() throws Exception {
    Git git = createProject();
    RevCommit initialHead = getRemoteHead();
    PushOneCommit.Result change =
        createChange(git, "Change 1", "a.txt", "content");
    submit(change.getChangeId());

    RevCommit oldHead = getRemoteHead();
    checkout(git, initialHead.getId().getName());
    createChange(git, "Change 2", "b.txt", "other content");
    PushOneCommit.Result change3 =
        createChange(git, "Change 3", "b.txt", "different content");
    submitWithConflict(change3.getChangeId());
    assertThat(getRemoteHead()).isEqualTo(oldHead);
    assertCurrentRevision(change3.getChangeId(), 1, change3.getCommitId());
    assertSubmitter(change3.getChangeId(), 1);
  }

  @Test
  public void submitMultipleChanges() throws Exception {
    Git git = createProject();
    RevCommit initialHead = getRemoteHead();

    checkout(git, initialHead.getId().getName());
    PushOneCommit.Result change2 = createChange(git, "Change 2", "b", "b");

    checkout(git, initialHead.getId().getName());
    PushOneCommit.Result change3 = createChange(git, "Change 3", "c", "c");

    checkout(git, initialHead.getId().getName());
    PushOneCommit.Result change4 = createChange(git, "Change 4", "d", "d");

    submitStatusOnly(change2.getChangeId());
    submitStatusOnly(change3.getChangeId());
    submit(change4.getChangeId());

    List<RevCommit> log = getRemoteLog();
    assertThat(log.get(0).getShortMessage()).isEqualTo(
        change4.getCommit().getShortMessage());
    assertThat(log.get(0).getParent(0)).isEqualTo(log.get(1));

    assertThat(log.get(1).getShortMessage()).isEqualTo(
        change3.getCommit().getShortMessage());
    assertThat(log.get(1).getParent(0)).isEqualTo(log.get(2));

    assertThat(log.get(2).getShortMessage()).isEqualTo(
        change2.getCommit().getShortMessage());
    assertThat(log.get(2).getParent(0)).isEqualTo(log.get(3));

    assertThat(log.get(3).getId()).isEqualTo(initialHead.getId());
  }

  @Test
  public void submitDependentNonConflictingChangesOutOfOrder() throws Exception {
    Git git = createProject();
    RevCommit initialHead = getRemoteHead();

    checkout(git, initialHead.getId().getName());
    PushOneCommit.Result change2 = createChange(git, "Change 2", "b", "b");
    PushOneCommit.Result change3 = createChange(git, "Change 3", "c", "c");
    assertThat(change3.getCommit().getParent(0)).isEqualTo(change2.getCommit());

    // Submit succeeds; change3 is successfully cherry-picked onto head.
    submit(change3.getChangeId());
    // Submit succeeds; change2 is successfully cherry-picked onto head
    // (which was change3's cherry-pick).
    submit(change2.getChangeId());

    // change2 is the new tip.
    List<RevCommit> log = getRemoteLog();
    assertThat(log.get(0).getShortMessage()).isEqualTo(
        change2.getCommit().getShortMessage());
    assertThat(log.get(0).getParent(0)).isEqualTo(log.get(1));

    assertThat(log.get(1).getShortMessage()).isEqualTo(
        change3.getCommit().getShortMessage());
    assertThat(log.get(1).getParent(0)).isEqualTo(log.get(2));

    assertThat(log.get(2).getId()).isEqualTo(initialHead.getId());
  }

  @Test
  public void submitDependentConflictingChangesOutOfOrder() throws Exception {
    Git git = createProject();
    RevCommit initialHead = getRemoteHead();

    checkout(git, initialHead.getId().getName());
    PushOneCommit.Result change2 = createChange(git, "Change 2", "b", "b1");
    PushOneCommit.Result change3 = createChange(git, "Change 3", "b", "b2");
    assertThat(change3.getCommit().getParent(0)).isEqualTo(change2.getCommit());

    // Submit fails; change3 contains the delta "b1" -> "b2", which cannot be
    // applied against tip.
    submitWithConflict(change3.getChangeId());

    ChangeInfo info3 = get(change3.getChangeId(), ListChangesOption.MESSAGES);
    assertThat(info3.status).isEqualTo(ChangeStatus.NEW);
    assertThat(Iterables.getLast(info3.messages).message.toLowerCase())
        .contains("path conflict");

    // Tip has not changed.
    List<RevCommit> log = getRemoteLog();
    assertThat(log.get(0)).isEqualTo(initialHead.getId());
  }

  @Test
  public void submitSubsetOfDependentChanges() throws Exception {
    Git git = createProject();
    RevCommit initialHead = getRemoteHead();

    checkout(git, initialHead.getId().getName());
    createChange(git, "Change 2", "b", "b");
    PushOneCommit.Result change3 = createChange(git, "Change 3", "c", "c");
    createChange(git, "Change 4", "d", "d");
    PushOneCommit.Result change5 = createChange(git, "Change 5", "e", "e");

    // Out of the above, only submit 3 and 5.
    submitStatusOnly(change3.getChangeId());
    submit(change5.getChangeId());

    ChangeInfo info3 = get(change3.getChangeId());
    assertThat(info3.status).isEqualTo(ChangeStatus.MERGED);

    List<RevCommit> log = getRemoteLog();
    assertThat(log.get(0).getShortMessage())
        .isEqualTo(change5.getCommit().getShortMessage());
    assertThat(log.get(1).getShortMessage())
        .isEqualTo(change3.getCommit().getShortMessage());
    assertThat(log.get(2).getShortMessage())
        .isEqualTo(initialHead.getShortMessage());
  }

  @Test
  public void submitChangeAfterParentFailsDueToConflict() throws Exception {
    Git git = createProject();
    RevCommit initialHead = getRemoteHead();

    checkout(git, initialHead.getId().getName());
    PushOneCommit.Result change2 = createChange(git, "Change 2", "b", "b1");
    submit(change2.getChangeId());

    checkout(git, initialHead.getId().getName());
    PushOneCommit.Result change3 = createChange(git, "Change 3", "b", "b2");
    assertThat(change3.getCommit().getParent(0)).isEqualTo(initialHead);
    PushOneCommit.Result change4 = createChange(git, "Change 3", "c", "c3");

    submitStatusOnly(change3.getChangeId());
    submitStatusOnly(change4.getChangeId());

    // Merge fails; change3 contains the delta "b1" -> "b2", which cannot be
    // applied against tip.
    submitWithConflict(change3.getChangeId());

    // change4 is a clean merge, so should succeed in the same run where change3
    // failed.
    ChangeInfo info4 = get(change4.getChangeId());
    assertThat(info4.status).isEqualTo(ChangeStatus.MERGED);
    List<RevCommit> log = getRemoteLog();
    assertThat(log.get(0).getShortMessage())
        .isEqualTo(change4.getCommit().getShortMessage());
    assertThat(log.get(1).getShortMessage())
        .isEqualTo(change2.getCommit().getShortMessage());
  }
}