/*
 * MIT License
 *
 * Copyright (c) 2020-present Cloudogu GmbH and Contributors
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */
    
package sonia.scm.it;

import com.google.common.base.Charsets;
import com.google.common.io.Files;
import org.eclipse.jgit.api.CommitCommand;
import org.eclipse.jgit.api.Git;
import org.eclipse.jgit.api.errors.GitAPIException;
import org.eclipse.jgit.transport.CredentialsProvider;
import org.eclipse.jgit.transport.PushResult;
import org.eclipse.jgit.transport.RemoteRefUpdate;
import org.eclipse.jgit.transport.RemoteRefUpdate.Status;
import org.eclipse.jgit.transport.UsernamePasswordCredentialsProvider;
import org.junit.After;
import org.junit.AfterClass;
import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.TemporaryFolder;
import sonia.scm.it.utils.RestUtil;
import sonia.scm.it.utils.TestData;
import sonia.scm.web.VndMediaType;

import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.IOException;

import static org.junit.Assert.assertEquals;
import static sonia.scm.it.utils.RestUtil.given;

/**
 * Integration Tests for Git with non fast-forward pushes.
 */
public class GitNonFastForwardITCase {

  private File workingCopy;
  private Git git;

  @Rule
  public TemporaryFolder tempFolder = new TemporaryFolder();

  @Before
  public void createAndCloneTestRepository() throws IOException, GitAPIException {
    TestData.createDefault();
    this.workingCopy = tempFolder.newFolder();

    this.git = clone(RestUtil.BASE_URL.toASCIIString() + "repo/scmadmin/HeartOfGold-git");
  }

  @After
  public void cleanup() {
    TestData.cleanup();
  }

  /**
   * Ensures that the normal behaviour (non fast-forward is allowed), is restored after the tests are executed.
   */
  @AfterClass
  public static void allowNonFastForward() {
    setNonFastForwardDisallowed(false);
  }

  @Test
  public void testGitPushAmendWithoutForce() throws IOException, GitAPIException {
    setNonFastForwardDisallowed(false);

    addTestFileToWorkingCopyAndCommit("a");
    pushAndAssert(false, Status.OK);

    addTestFileToWorkingCopyAndCommitAmend("c");
    pushAndAssert(false, Status.REJECTED_NONFASTFORWARD);
  }

  @Test
  public void testGitPushAmendWithForce() throws IOException, GitAPIException {
    setNonFastForwardDisallowed(false);

    addTestFileToWorkingCopyAndCommit("a");
    pushAndAssert(false, Status.OK);

    addTestFileToWorkingCopyAndCommitAmend("c");
    pushAndAssert(true, Status.OK);
  }

  @Test
  public void testGitPushAmendForceWithDisallowNonFastForward() throws GitAPIException, IOException {
    setNonFastForwardDisallowed(true);

    addTestFileToWorkingCopyAndCommit("a");
    pushAndAssert(false, Status.OK);

    addTestFileToWorkingCopyAndCommitAmend("c");
    pushAndAssert(true, Status.REJECTED_OTHER_REASON);

    setNonFastForwardDisallowed(false);
  }

  private CredentialsProvider createCredentialProvider() {
    return new UsernamePasswordCredentialsProvider(
      RestUtil.ADMIN_USERNAME, RestUtil.ADMIN_PASSWORD
    );
  }

  private Git clone(String url) throws GitAPIException {
    return Git.cloneRepository()
      .setDirectory(workingCopy)
      .setURI(url)
      .setCredentialsProvider(createCredentialProvider())
      .call();
  }

  private void addTestFileToWorkingCopyAndCommit(String name) throws IOException, GitAPIException {
    addTestFile(name);
    prepareCommit()
      .setMessage("added ".concat(name))
      .call();
  }

  private void addTestFile(String name) throws IOException, GitAPIException {
    String filename = name.concat(".txt");
    Files.write(name, new File(workingCopy, filename), Charsets.UTF_8);
    git.add().addFilepattern(filename).call();
  }

  private CommitCommand prepareCommit() {
    return git.commit()
      .setAuthor("Trillian McMillian", "trillian@hitchhiker.com");
  }

  private void pushAndAssert(boolean force, Status expectedStatus) throws GitAPIException {
    Iterable<PushResult> results = push(force);
    assertStatus(results, expectedStatus);
  }

  private Iterable<PushResult> push(boolean force) throws GitAPIException {
    return git.push()
      .setRemote("origin")
      .add("master")
      .setForce(force)
      .setCredentialsProvider(createCredentialProvider())
      .call();
  }

  private void assertStatus(Iterable<PushResult> results, Status expectedStatus) {
    for ( PushResult pushResult : results ) {
      assertStatus(pushResult, expectedStatus);
    }
  }

  private void assertStatus(PushResult pushResult, Status expectedStatus) {
    for ( RemoteRefUpdate remoteRefUpdate : pushResult.getRemoteUpdates() ) {
      assertEquals(expectedStatus, remoteRefUpdate.getStatus());
    }
  }

  private void addTestFileToWorkingCopyAndCommitAmend(String name) throws IOException, GitAPIException {
    addTestFile(name);
    prepareCommit()
      .setMessage("amend commit, because of missing ".concat(name))
      .setAmend(true)
      .call();
  }

  private static void setNonFastForwardDisallowed(boolean nonFastForwardDisallowed) {
    String config = String.format("{'disabled': false, 'gcExpression': null, 'nonFastForwardDisallowed': %s}", nonFastForwardDisallowed)
      .replace('\'', '"');

    given(VndMediaType.PREFIX + "gitConfig" + VndMediaType.SUFFIX)
      .body(config)

      .when()
      .put(RestUtil.REST_BASE_URL.toASCIIString() + "config/git" )

      .then()
      .statusCode(HttpServletResponse.SC_NO_CONTENT);
  }

}
