/*
    * Copyright (C) 2011, Mathias Kinzler <mathias.kinzler@sap.com> and others
    *
    * This program and the accompanying materials are made available under the
    * terms of the Eclipse Distribution License v. 1.0 which is available at
    * https://www.eclipse.org/org/documents/edl-v10.php.
    *
    * SPDX-License-Identifier: BSD-3-Clause
    */
  package org.eclipse.jgit.api;
  
  import static java.nio.charset.StandardCharsets.UTF_8;
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertFalse;
  import static org.junit.Assert.assertNotNull;
  import static org.junit.Assert.assertNull;
  import static org.junit.Assert.assertTrue;
  
  import java.io.ByteArrayOutputStream;
  import java.io.File;
  import java.io.FileInputStream;
  import java.io.FileOutputStream;
  import java.io.IOException;
  
  import org.eclipse.jgit.api.CreateBranchCommand.SetupUpstreamMode;
  import org.eclipse.jgit.api.MergeResult.MergeStatus;
  import org.eclipse.jgit.api.RebaseResult.Status;
  import org.eclipse.jgit.junit.RepositoryTestCase;
  import org.eclipse.jgit.lib.ConfigConstants;
  import org.eclipse.jgit.lib.Constants;
  import org.eclipse.jgit.lib.ObjectId;
  import org.eclipse.jgit.lib.Ref;
  import org.eclipse.jgit.lib.Repository;
  import org.eclipse.jgit.lib.RepositoryState;
  import org.eclipse.jgit.lib.StoredConfig;
  import org.eclipse.jgit.merge.MergeStrategy;
  import org.eclipse.jgit.revwalk.RevCommit;
  import org.eclipse.jgit.revwalk.RevWalk;
  import org.eclipse.jgit.transport.RefSpec;
  import org.eclipse.jgit.transport.RemoteConfig;
  import org.eclipse.jgit.transport.URIish;
  import org.junit.Before;
  import org.junit.Test;
  
  public class PullCommandWithRebaseTest extends RepositoryTestCase {
  	/** Second Test repository */
  	protected Repository dbTarget;
  
  	private Git source;
  
  	private Git target;
  
  	private File sourceFile;
  
  	private File targetFile;
  
  	@Test
  	public void testPullFastForward() throws Exception {
  		PullResult res = target.pull().call();
  		// nothing to update since we don't have different data yet
  		assertTrue(res.getFetchResult().getTrackingRefUpdates().isEmpty());
  		assertEquals(Status.UP_TO_DATE, res.getRebaseResult().getStatus());
  
  		assertFileContentsEqual(targetFile, "Hello world");
  
  		// change the source file
  		writeToFile(sourceFile, "Another change");
  		source.add().addFilepattern("SomeFile.txt").call();
  		source.commit().setMessage("Some change in remote").call();
  
  		res = target.pull().call();
  
  		assertFalse(res.getFetchResult().getTrackingRefUpdates().isEmpty());
  		assertEquals(Status.FAST_FORWARD, res.getRebaseResult().getStatus());
  		assertFileContentsEqual(targetFile, "Another change");
  		assertEquals(RepositoryState.SAFE, target.getRepository()
  				.getRepositoryState());
  
  		res = target.pull().call();
  		assertEquals(Status.UP_TO_DATE, res.getRebaseResult().getStatus());
  	}
  
  	@Test
  	public void testPullFastForwardWithBranchInSource() throws Exception {
  		PullResult res = target.pull().call();
  		// nothing to update since we don't have different data yet
  		assertTrue(res.getFetchResult().getTrackingRefUpdates().isEmpty());
  		assertEquals(Status.UP_TO_DATE, res.getRebaseResult().getStatus());
  
  		assertFileContentsEqual(targetFile, "Hello world");
  
  		// change the source file
  		writeToFile(sourceFile, "Another change\n\n\n\nFoo");
  		source.add().addFilepattern("SomeFile.txt").call();
  		RevCommit initialCommit = source.commit()
  				.setMessage("Some change in remote").call();
  
  		// modify the source file in a branch
  		createBranch(initialCommit, "refs/heads/side");
 		checkoutBranch("refs/heads/side");
 		writeToFile(sourceFile, "Another change\n\n\n\nBoo");
 		source.add().addFilepattern("SomeFile.txt").call();
 		RevCommit sideCommit = source.commit()
 				.setMessage("Some change in remote").call();
 
 		// modify the source file on master
 		checkoutBranch("refs/heads/master");
 		writeToFile(sourceFile, "More change\n\n\n\nFoo");
 		source.add().addFilepattern("SomeFile.txt").call();
 		source.commit().setMessage("Some change in remote").call();
 
 		// merge side into master
 		MergeResult result = source.merge().include(sideCommit.getId())
 				.setStrategy(MergeStrategy.RESOLVE).call();
 		assertEquals(MergeStatus.MERGED, result.getMergeStatus());
 
 	}
 
 	@Test
 	public void testPullFastForwardDetachedHead() throws Exception {
 		Repository repository = source.getRepository();
 		writeToFile(sourceFile, "2nd commit");
 		source.add().addFilepattern("SomeFile.txt").call();
 		source.commit().setMessage("2nd commit").call();
 
 		try (RevWalk revWalk = new RevWalk(repository)) {
 			// git checkout HEAD^
 			String initialBranch = repository.getBranch();
 			Ref initialRef = repository.findRef(Constants.HEAD);
 			RevCommit initialCommit = revWalk
 					.parseCommit(initialRef.getObjectId());
 			assertEquals("this test need linear history", 1,
 					initialCommit.getParentCount());
 			source.checkout().setName(initialCommit.getParent(0).getName())
 					.call();
 			assertFalse("expected detached HEAD",
 					repository.getFullBranch().startsWith(Constants.R_HEADS));
 
 			// change and commit another file
 			File otherFile = new File(sourceFile.getParentFile(),
 					System.currentTimeMillis() + ".tst");
 			writeToFile(otherFile, "other 2nd commit");
 			source.add().addFilepattern(otherFile.getName()).call();
 			RevCommit newCommit = source.commit().setMessage("other 2nd commit")
 					.call();
 
 			// git pull --rebase initialBranch
 			source.pull().setRebase(true).setRemote(".")
 					.setRemoteBranchName(initialBranch)
 					.call();
 
 			assertEquals(RepositoryState.SAFE,
 					source.getRepository().getRepositoryState());
 			Ref head = source.getRepository().findRef(Constants.HEAD);
 			RevCommit headCommit = revWalk.parseCommit(head.getObjectId());
 
 			// HEAD^ == initialCommit, no merge commit
 			assertEquals(1, headCommit.getParentCount());
 			assertEquals(initialCommit, headCommit.getParent(0));
 
 			// both contributions for both commits are available
 			assertFileContentsEqual(sourceFile, "2nd commit");
 			assertFileContentsEqual(otherFile, "other 2nd commit");
 			// HEAD has same message as rebased commit
 			assertEquals(newCommit.getShortMessage(),
 					headCommit.getShortMessage());
 		}
 	}
 
 	@Test
 	public void testPullConflict() throws Exception {
 		PullResult res = target.pull().call();
 		// nothing to update since we don't have different data yet
 		assertTrue(res.getFetchResult().getTrackingRefUpdates().isEmpty());
 		assertEquals(Status.UP_TO_DATE, res.getRebaseResult().getStatus());
 
 		assertFileContentsEqual(targetFile, "Hello world");
 
 		// change the source file
 		writeToFile(sourceFile, "Source change");
 		source.add().addFilepattern("SomeFile.txt").call();
 		source.commit().setMessage("Source change in remote").call();
 
 		// change the target file
 		writeToFile(targetFile, "Target change");
 		target.add().addFilepattern("SomeFile.txt").call();
 		target.commit().setMessage("Target change in local").call();
 
 		res = target.pull().call();
 
 		String remoteUri = target
 				.getRepository()
 				.getConfig()
 				.getString(ConfigConstants.CONFIG_REMOTE_SECTION, "origin",
 						ConfigConstants.CONFIG_KEY_URL);
 
 		assertFalse(res.getFetchResult().getTrackingRefUpdates().isEmpty());
 		assertEquals(Status.STOPPED, res.getRebaseResult().getStatus());
 		String result = "<<<<<<< Upstream, based on branch 'master' of "
 				+ remoteUri
 				+ "\nSource change\n=======\nTarget change\n>>>>>>> 42453fd Target change in local\n";
 		assertFileContentsEqual(targetFile, result);
 		assertEquals(RepositoryState.REBASING_MERGE, target
 				.getRepository().getRepositoryState());
 	}
 
 	@Test
 	public void testPullLocalConflict() throws Exception {
 		target.branchCreate().setName("basedOnMaster").setStartPoint(
 				"refs/heads/master").setUpstreamMode(SetupUpstreamMode.NOTRACK)
 				.call();
 		StoredConfig config = target.getRepository().getConfig();
 		config.setString("branch", "basedOnMaster", "remote", ".");
 		config.setString("branch", "basedOnMaster", "merge",
 				"refs/heads/master");
 		config.setBoolean("branch", "basedOnMaster", "rebase", true);
 		config.save();
 		target.getRepository().updateRef(Constants.HEAD).link(
 				"refs/heads/basedOnMaster");
 		PullResult res = target.pull().call();
 		// nothing to update since we don't have different data yet
 		assertNull(res.getFetchResult());
 		assertEquals(Status.UP_TO_DATE, res.getRebaseResult().getStatus());
 
 		assertFileContentsEqual(targetFile, "Hello world");
 
 		// change the file in master
 		target.getRepository().updateRef(Constants.HEAD).link(
 				"refs/heads/master");
 		writeToFile(targetFile, "Master change");
 		target.add().addFilepattern("SomeFile.txt").call();
 		target.commit().setMessage("Source change in master").call();
 
 		// change the file in slave
 		target.getRepository().updateRef(Constants.HEAD).link(
 				"refs/heads/basedOnMaster");
 		writeToFile(targetFile, "Slave change");
 		target.add().addFilepattern("SomeFile.txt").call();
 		target.commit().setMessage("Source change in based on master").call();
 
 		res = target.pull().call();
 
 		assertNull(res.getFetchResult());
 		assertEquals(Status.STOPPED, res.getRebaseResult().getStatus());
 		String result = "<<<<<<< Upstream, based on branch 'master' of local repository\n"
 				+ "Master change\n=======\nSlave change\n>>>>>>> 4049c9e Source change in based on master\n";
 		assertFileContentsEqual(targetFile, result);
 		assertEquals(RepositoryState.REBASING_MERGE, target
 				.getRepository().getRepositoryState());
 	}
 
     @Test
 	public void testPullFastForwardWithLocalCommitAndRebaseFlagSet() throws Exception {
 		final String SOURCE_COMMIT_MESSAGE = "Source commit message for rebase flag test";
 		final String TARGET_COMMIT_MESSAGE = "Target commit message for rebase flag test";
 
 		assertFalse(SOURCE_COMMIT_MESSAGE.equals(TARGET_COMMIT_MESSAGE));
 
 		final String SOURCE_FILE_CONTENTS = "Source change";
 		final String NEW_FILE_CONTENTS = "New file from target";
 
 		// make sure the config for target says we should pull with merge
 		// we will override this later with the setRebase method
 		StoredConfig targetConfig = dbTarget.getConfig();
 		targetConfig.setBoolean("branch", "master", "rebase", false);
 		targetConfig.save();
 
 		// create commit in source
 		writeToFile(sourceFile, SOURCE_FILE_CONTENTS);
 		source.add().addFilepattern(sourceFile.getName()).call();
 		source.commit().setMessage(SOURCE_COMMIT_MESSAGE).call();
 
 		// create commit in target, not conflicting with the new commit in source
 		File newFile = new File(dbTarget.getWorkTree().getPath() + "/newFile.txt");
 		writeToFile(newFile, NEW_FILE_CONTENTS);
 		target.add().addFilepattern(newFile.getName()).call();
 		target.commit().setMessage(TARGET_COMMIT_MESSAGE).call();
 
 		// verify that rebase is set to false in the config
 		assertFalse(targetConfig.getBoolean("branch", "master", "rebase", true));
 
 		// pull with rebase - local commit in target should be on top
 		PullResult pullResult = target.pull().setRebase(true).call();
 
 		// make sure pull is considered successful
 		assertTrue(pullResult.isSuccessful());
 
 		// verify rebase result is ok
 		RebaseResult rebaseResult = pullResult.getRebaseResult();
 		assertNotNull(rebaseResult);
 		assertNull(rebaseResult.getFailingPaths());
 		assertEquals(Status.OK, rebaseResult.getStatus());
 
 		// Get the HEAD and HEAD~1 commits
 		Repository targetRepo = target.getRepository();
 		try (RevWalk revWalk = new RevWalk(targetRepo)) {
 			ObjectId headId = targetRepo.resolve(Constants.HEAD);
 			RevCommit root = revWalk.parseCommit(headId);
 			revWalk.markStart(root);
 			// HEAD
 			RevCommit head = revWalk.next();
 			// HEAD~1
 			RevCommit beforeHead = revWalk.next();
 
 			// verify the commit message on the HEAD commit
 			assertEquals(TARGET_COMMIT_MESSAGE, head.getFullMessage());
 			// verify the commit just before HEAD
 			assertEquals(SOURCE_COMMIT_MESSAGE, beforeHead.getFullMessage());
 
 			// verify file states
 			assertFileContentsEqual(sourceFile, SOURCE_FILE_CONTENTS);
 			assertFileContentsEqual(newFile, NEW_FILE_CONTENTS);
 			// verify repository state
 			assertEquals(RepositoryState.SAFE, target
 				.getRepository().getRepositoryState());
 		}
 	}
 
 	@Override
 	@Before
 	public void setUp() throws Exception {
 		super.setUp();
 		dbTarget = createWorkRepository();
 		source = new Git(db);
 		target = new Git(dbTarget);
 
 		// put some file in the source repo
 		sourceFile = new File(db.getWorkTree(), "SomeFile.txt");
 		writeToFile(sourceFile, "Hello world");
 		// and commit it
 		source.add().addFilepattern("SomeFile.txt").call();
 		source.commit().setMessage("Initial commit for source").call();
 
 		// configure the target repo to connect to the source via "origin"
 		StoredConfig targetConfig = dbTarget.getConfig();
 		targetConfig.setString("branch", "master", "remote", "origin");
 		targetConfig
 				.setString("branch", "master", "merge", "refs/heads/master");
 		RemoteConfig config = new RemoteConfig(targetConfig, "origin");
 
 		config
 				.addURI(new URIish(source.getRepository().getWorkTree()
 						.getAbsolutePath()));
 		config.addFetchRefSpec(new RefSpec(
 				"+refs/heads/*:refs/remotes/origin/*"));
 		config.update(targetConfig);
 		targetConfig.save();
 
 		targetFile = new File(dbTarget.getWorkTree(), "SomeFile.txt");
 		// make sure we have the same content
 		target.pull().call();
 		target.checkout().setStartPoint("refs/remotes/origin/master").setName(
 				"master").call();
 
 		targetConfig
 				.setString("branch", "master", "merge", "refs/heads/master");
 		targetConfig.setBoolean("branch", "master", "rebase", true);
 		targetConfig.save();
 
 		assertFileContentsEqual(targetFile, "Hello world");
 	}
 
 	private static void writeToFile(File actFile, String string)
 			throws IOException {
 		try (FileOutputStream fos = new FileOutputStream(actFile)) {
 			fos.write(string.getBytes(UTF_8));
 		}
 	}
 
 	private static void assertFileContentsEqual(File actFile, String string)
 			throws IOException {
 		ByteArrayOutputStream bos = new ByteArrayOutputStream();
 		byte[] buffer = new byte[100];
 		try (FileInputStream fis = new FileInputStream(actFile)) {
 			int read = fis.read(buffer);
 			while (read > 0) {
 				bos.write(buffer, 0, read);
 				read = fis.read(buffer);
 			}
 			String content = new String(bos.toByteArray(), UTF_8);
 			assertEquals(string, content);
 		}
 	}
 }