// 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.tools.hooks;

import static com.google.common.truth.Truth.assertWithMessage;
import static com.google.common.truth.TruthJUnit.assume;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertTrue;

import com.google.gerrit.server.util.HostPlatform;
import java.io.File;
import java.io.IOException;
import java.util.Date;
import java.util.TimeZone;
import org.eclipse.jgit.dircache.DirCacheBuilder;
import org.eclipse.jgit.dircache.DirCacheEntry;
import org.eclipse.jgit.lib.CommitBuilder;
import org.eclipse.jgit.lib.Constants;
import org.eclipse.jgit.lib.FileMode;
import org.eclipse.jgit.lib.ObjectId;
import org.eclipse.jgit.lib.ObjectInserter;
import org.eclipse.jgit.lib.PersonIdent;
import org.eclipse.jgit.lib.RefUpdate;
import org.eclipse.jgit.lib.RefUpdate.Result;
import org.junit.Before;
import org.junit.BeforeClass;
import org.junit.Test;

public class CommitMsgHookTest extends HookTestCase {
  private final String SOB1 = "Signed-off-by: J Author <ja@example.com>\n";
  private final String SOB2 = "Signed-off-by: J Committer <jc@example.com>\n";

  @BeforeClass
  public static void skipIfWin32Platform() {
    assume().that(HostPlatform.isWin32()).isFalse();
  }

  @Override
  @Before
  public void setUp() throws Exception {
    super.setUp();
    final Date when = author.getWhen();
    final TimeZone tz = author.getTimeZone();

    author = new PersonIdent("J. Author", "ja@example.com");
    author = new PersonIdent(author, when, tz);

    committer = new PersonIdent("J. Committer", "jc@example.com");
    committer = new PersonIdent(committer, when, tz);
  }

  @Test
  public void emptyMessages() throws Exception {
    // Empty input must yield empty output so commit will abort.
    // Note we must consider different commit templates formats.
    //
    hookDoesNotModify("");
    hookDoesNotModify(" ");
    hookDoesNotModify("\n");
    hookDoesNotModify("\n\n");
    hookDoesNotModify("  \n  ");

    hookDoesNotModify("#");
    hookDoesNotModify("#\n");
    hookDoesNotModify("# on branch master\n# Untracked files:\n");
    hookDoesNotModify("\n# on branch master\n# Untracked files:\n");
    hookDoesNotModify("\n\n# on branch master\n# Untracked files:\n");

    hookDoesNotModify(
        "\n# on branch master\ndiff --git a/src b/src\n"
            + "new file mode 100644\nindex 0000000..c78b7f0\n");
  }

  @Test
  public void changeIdAlreadySet() throws Exception {
    // If a Change-Id is already present in the footer, the hook must
    // not modify the message but instead must leave the identity alone.
    //
    hookDoesNotModify(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: Iaeac9b4149291060228ef0154db2985a31111335\n");
    hookDoesNotModify(
        "fix: this thing\n"
            + //
            "\n"
            + //
            "Change-Id: I388bdaf52ed05b55e62a22d0a20d2c1ae0d33e7e\n");
    hookDoesNotModify(
        "fix-a-widget: this thing\n"
            + //
            "\n"
            + //
            "Change-Id: Id3bc5359d768a6400450283e12bdfb6cd135ea4b\n");
    hookDoesNotModify(
        "FIX: this thing\n"
            + //
            "\n"
            + //
            "Change-Id: I1b55098b5a2cce0b3f3da783dda50d5f79f873fa\n");
    hookDoesNotModify(
        "Fix-A-Widget: this thing\n"
            + //
            "\n"
            + //
            "Change-Id: I4f4e2e1e8568ddc1509baecb8c1270a1fb4b6da7\n");
  }

  @Test
  public void timeAltersId() throws Exception {
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: I7fc3876fee63c766a2063df97fbe04a2dddd8d7c\n", //
        call("a\n"));

    tick();
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: I3251906b99dda598a58a6346d8126237ee1ea800\n", //
        call("a\n"));

    tick();
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: I69adf9208d828f41a3d7e41afbca63aff37c0c5c\n", //
        call("a\n"));
  }

  @Test
  public void firstParentAltersId() throws Exception {
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: I7fc3876fee63c766a2063df97fbe04a2dddd8d7c\n", //
        call("a\n"));

    setHEAD();
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: I51e86482bde7f92028541aaf724d3a3f996e7ea2\n", //
        call("a\n"));
  }

  @Test
  public void dirCacheAltersId() throws Exception {
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: I7fc3876fee63c766a2063df97fbe04a2dddd8d7c\n", //
        call("a\n"));

    final DirCacheBuilder builder = repository.lockDirCache().builder();
    builder.add(file("A"));
    assertTrue(builder.commit());

    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: If56597ea9759f23b070677ea6f064c60c38da631\n", //
        call("a\n"));
  }

  @Test
  public void singleLineMessages() throws Exception {
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: I7fc3876fee63c766a2063df97fbe04a2dddd8d7c\n", //
        call("a\n"));

    assertEquals(
        "fix: this thing\n"
            + //
            "\n"
            + //
            "Change-Id: I0f13d0e6c739ca3ae399a05a93792e80feb97f37\n", //
        call("fix: this thing\n"));
    assertEquals(
        "fix-a-widget: this thing\n"
            + //
            "\n"
            + //
            "Change-Id: I1a1a0c751e4273d532e4046a501a612b9b8a775e\n", //
        call("fix-a-widget: this thing\n"));

    assertEquals(
        "FIX: this thing\n"
            + //
            "\n"
            + //
            "Change-Id: If816d944c57d3893b60cf10c65931fead1290d97\n", //
        call("FIX: this thing\n"));
    assertEquals(
        "Fix-A-Widget: this thing\n"
            + //
            "\n"
            + //
            "Change-Id: I3e18d00cbda2ba1f73aeb63ed8c7d57d7fd16c76\n", //
        call("Fix-A-Widget: this thing\n"));
  }

  @Test
  public void multiLineMessagesWithoutFooter() throws Exception {
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "b\n"
            + //
            "\n"
            + //
            "Change-Id: Id0b4f42d3d6fc1569595c9b97cb665e738486f5d\n", //
        call("a\n\nb\n"));

    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "b\nc\nd\ne\n"
            + //
            "\n"
            + //
            "Change-Id: I7d237b20058a0f46cc3f5fabc4a0476877289d75\n", //
        call("a\n\nb\nc\nd\ne\n"));

    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "b\nc\nd\ne\n"
            + //
            "\n"
            + //
            "f\ng\nh\n"
            + //
            "\n"
            + //
            "Change-Id: I382e662f47bf164d6878b7fe61637873ab7fa4e8\n", //
        call("a\n\nb\nc\nd\ne\n\nf\ng\nh\n"));
  }

  @Test
  public void singleLineMessagesWithSignedOffBy() throws Exception {
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: I7fc3876fee63c766a2063df97fbe04a2dddd8d7c\n"
            + //
            SOB1, //
        call("a\n\n" + SOB1));

    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: I7fc3876fee63c766a2063df97fbe04a2dddd8d7c\n"
            + //
            SOB1
            + //
            SOB2, //
        call("a\n\n" + SOB1 + SOB2));
  }

  @Test
  public void multiLineMessagesWithSignedOffBy() throws Exception {
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "b\nc\nd\ne\n"
            + //
            "\n"
            + //
            "f\ng\nh\n"
            + //
            "\n"
            + //
            "Change-Id: I382e662f47bf164d6878b7fe61637873ab7fa4e8\n"
            + //
            SOB1, //
        call("a\n\nb\nc\nd\ne\n\nf\ng\nh\n\n" + SOB1));

    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "b\nc\nd\ne\n"
            + //
            "\n"
            + //
            "f\ng\nh\n"
            + //
            "\n"
            + //
            "Change-Id: I382e662f47bf164d6878b7fe61637873ab7fa4e8\n"
            + //
            SOB1
            + //
            SOB2, //
        call(
            "a\n"
                + //
                "\n"
                + //
                "b\nc\nd\ne\n"
                + //
                "\n"
                + //
                "f\ng\nh\n"
                + //
                "\n"
                + //
                SOB1
                + //
                SOB2));

    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "b: not a footer\nc\nd\ne\n"
            + //
            "\n"
            + //
            "f\ng\nh\n"
            + //
            "\n"
            + //
            "Change-Id: I8869aabd44b3017cd55d2d7e0d546a03e3931ee2\n"
            + //
            SOB1
            + //
            SOB2, //
        call(
            "a\n"
                + //
                "\n"
                + //
                "b: not a footer\nc\nd\ne\n"
                + //
                "\n"
                + //
                "f\ng\nh\n"
                + //
                "\n"
                + //
                SOB1
                + //
                SOB2));
  }

  @Test
  public void noteInMiddle() throws Exception {
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "NOTE: This\n"
            + //
            "does not fix it.\n"
            + //
            "\n"
            + //
            "Change-Id: I988a127969a6ee5e58db546aab74fc46e66847f8\n", //
        call(
            "a\n"
                + //
                "\n"
                + //
                "NOTE: This\n"
                + //
                "does not fix it.\n"));
  }

  @Test
  public void kernelStyleFooter() throws Exception {
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: I1bd787f9e7590a2ac82b02c404c955ffb21877c4\n"
            + //
            SOB1
            + //
            "[ja: Fixed\n"
            + //
            "     the indentation]\n"
            + //
            SOB2, //
        call(
            "a\n"
                + //
                "\n"
                + //
                SOB1
                + //
                "[ja: Fixed\n"
                + //
                "     the indentation]\n"
                + //
                SOB2));
  }

  @Test
  public void changeIdAfterBugOrIssue() throws Exception {
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Bug: 42\n"
            + //
            "Change-Id: I8c0321227c4324e670b9ae8cf40eccc87af21b1b\n"
            + //
            SOB1, //
        call(
            "a\n"
                + //
                "\n"
                + //
                "Bug: 42\n"
                + //
                SOB1));

    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Issue: 42\n"
            + //
            "Change-Id: Ie66e07d89ae5b114c0975b49cf326e90331dd822\n"
            + //
            SOB1, //
        call(
            "a\n"
                + //
                "\n"
                + //
                "Issue: 42\n"
                + //
                SOB1));
  }

  @Test
  public void commitDashV() throws Exception {
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "Change-Id: I7fc3876fee63c766a2063df97fbe04a2dddd8d7c\n"
            + //
            SOB1
            + //
            SOB2, //
        call(
            "a\n"
                + //
                "\n"
                + //
                SOB1
                + //
                SOB2
                + //
                "\n"
                + //
                "# on branch master\n"
                + //
                "diff --git a/src b/src\n"
                + //
                "new file mode 100644\n"
                + //
                "index 0000000..c78b7f0\n"));
  }

  @Test
  public void withEndingURL() throws Exception {
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "http://example.com/ fixes this\n"
            + //
            "\n"
            + //
            "Change-Id: I3b7e4e16b503ce00f07ba6ad01d97a356dad7701\n", //
        call(
            "a\n"
                + //
                "\n"
                + //
                "http://example.com/ fixes this\n"));
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "https://example.com/ fixes this\n"
            + //
            "\n"
            + //
            "Change-Id: I62b9039e2fc0dce274af55e8f99312a8a80a805d\n", //
        call(
            "a\n"
                + //
                "\n"
                + //
                "https://example.com/ fixes this\n"));
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "ftp://example.com/ fixes this\n"
            + //
            "\n"
            + //
            "Change-Id: I71b05dc1f6b9a5540a53a693e64d58b65a8910e8\n", //
        call(
            "a\n"
                + //
                "\n"
                + //
                "ftp://example.com/ fixes this\n"));
    assertEquals(
        "a\n"
            + //
            "\n"
            + //
            "git://example.com/ fixes this\n"
            + //
            "\n"
            + //
            "Change-Id: Id34e942baa68d790633737d815ddf11bac9183e5\n", //
        call(
            "a\n"
                + //
                "\n"
                + //
                "git://example.com/ fixes this\n"));
  }

  @Test
  public void withFalseTags() throws Exception {
    assertEquals(
        "foo\n"
            + //
            "\n"
            + //
            "FakeLine:\n"
            + //
            "  foo\n"
            + //
            "  bar\n"
            + //
            "\n"
            + //
            "Change-Id: I67632a37fd2e08a35f766f52fc9a47f4ea868c55\n"
            + //
            "RealTag: abc\n", //
        call(
            "foo\n"
                + //
                "\n"
                + //
                "FakeLine:\n"
                + //
                "  foo\n"
                + //
                "  bar\n"
                + //
                "\n"
                + //
                "RealTag: abc\n"));
  }

  private void hookDoesNotModify(String in) throws Exception {
    assertEquals(in, call(in));
  }

  private String call(String body) throws Exception {
    final File tmp = write(body);
    try {
      final File hook = getHook("commit-msg");
      assertEquals(0, runHook(repository, hook, tmp.getAbsolutePath()));
      return read(tmp);
    } finally {
      tmp.delete();
    }
  }

  private DirCacheEntry file(String name) throws IOException {
    try (ObjectInserter oi = repository.newObjectInserter()) {
      final DirCacheEntry e = new DirCacheEntry(name);
      e.setFileMode(FileMode.REGULAR_FILE);
      e.setObjectId(oi.insert(Constants.OBJ_BLOB, Constants.encode(name)));
      oi.flush();
      return e;
    }
  }

  private void setHEAD() throws Exception {
    try (ObjectInserter oi = repository.newObjectInserter()) {
      final CommitBuilder commit = new CommitBuilder();
      commit.setTreeId(oi.insert(Constants.OBJ_TREE, new byte[] {}));
      commit.setAuthor(author);
      commit.setCommitter(committer);
      commit.setMessage("test\n");
      ObjectId commitId = oi.insert(commit);

      final RefUpdate ref = repository.updateRef(Constants.HEAD);
      ref.setNewObjectId(commitId);
      Result result = ref.forceUpdate();
      assertWithMessage(Constants.HEAD + " did not change: " + ref.getResult())
          .that(result)
          .isAnyOf(Result.FAST_FORWARD, Result.FORCED, Result.NEW, Result.NO_CHANGE);
    }
  }
}