/*
    * Copyright (C) 2011, GitHub Inc. 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.lib;
  
  import static org.junit.Assert.assertEquals;
  import static org.junit.Assert.assertNotNull;
  import static org.junit.Assert.assertNull;
  import static org.junit.Assert.fail;
  
  import org.eclipse.jgit.api.Git;
  import org.eclipse.jgit.errors.RevisionSyntaxException;
  import org.eclipse.jgit.junit.RepositoryTestCase;
  import org.eclipse.jgit.revwalk.RevCommit;
  import org.junit.Test;
  
  /**
   * Unit tests for resolving reflog-based revisions
   */
  public class ReflogResolveTest extends RepositoryTestCase {
  
  	@Test
  	public void resolveMasterCommits() throws Exception {
  		try (Git git = new Git(db)) {
  			writeTrashFile("file.txt", "content");
  			git.add().addFilepattern("file.txt").call();
  			RevCommit c1 = git.commit().setMessage("create file").call();
  			writeTrashFile("file.txt", "content2");
  			git.add().addFilepattern("file.txt").call();
  			RevCommit c2 = git.commit().setMessage("edit file").call();
  
  			assertEquals(c2, db.resolve("master@{0}"));
  			assertEquals(c1, db.resolve("master@{1}"));
  		}
  	}
  
  	@Test
  	public void resolveUnnamedCurrentBranchCommits() throws Exception {
  		try (Git git = new Git(db)) {
  			writeTrashFile("file.txt", "content");
  			git.add().addFilepattern("file.txt").call();
  			RevCommit c1 = git.commit().setMessage("create file").call();
  			writeTrashFile("file.txt", "content2");
  			git.add().addFilepattern("file.txt").call();
  			RevCommit c2 = git.commit().setMessage("edit file").call();
  
  			assertEquals(c2, db.resolve("master@{0}"));
  			assertEquals(c1, db.resolve("master@{1}"));
  
  			git.checkout().setCreateBranch(true).setName("newbranch")
  					.setStartPoint(c1).call();
  
  			// same as current branch, e.g. master
  			assertEquals(c1, db.resolve("@{0}"));
  			try {
  				assertEquals(c1, db.resolve("@{1}"));
  				fail(); // Looking at wrong ref, e.g HEAD
  			} catch (RevisionSyntaxException e) {
  				assertNotNull(e);
  			}
  
  			// detached head, read HEAD reflog
  			git.checkout().setName(c2.getName()).call();
  			assertEquals(c2, db.resolve("@{0}"));
  			assertEquals(c1, db.resolve("@{1}"));
  			assertEquals(c2, db.resolve("@{2}"));
  		}
  	}
  
  	@Test
  	public void resolveReflogParent() throws Exception {
  		try (Git git = new Git(db)) {
  			writeTrashFile("file.txt", "content");
  			git.add().addFilepattern("file.txt").call();
  			RevCommit c1 = git.commit().setMessage("create file").call();
  			writeTrashFile("file.txt", "content2");
  			git.add().addFilepattern("file.txt").call();
  			git.commit().setMessage("edit file").call();
  
  			assertEquals(c1, db.resolve("master@{0}~1"));
  		}
  	}
  
  	@Test
  	public void resolveNonExistingBranch() throws Exception {
  		try (Git git = new Git(db)) {
  			writeTrashFile("file.txt", "content");
  			git.add().addFilepattern("file.txt").call();
  			git.commit().setMessage("create file").call();
  			assertNull(db.resolve("notabranch@{7}"));
  		}
  	}
  
 	@Test
 	public void resolvePreviousBranch() throws Exception {
 		try (Git git = new Git(db)) {
 			writeTrashFile("file.txt", "content");
 			git.add().addFilepattern("file.txt").call();
 			RevCommit c1 = git.commit().setMessage("create file").call();
 			writeTrashFile("file.txt", "content2");
 			git.add().addFilepattern("file.txt").call();
 			RevCommit c2 = git.commit().setMessage("edit file").call();
 
 			git.checkout().setCreateBranch(true).setName("newbranch")
 					.setStartPoint(c1).call();
 
 			git.checkout().setName(c1.getName()).call();
 
 			git.checkout().setName("master").call();
 
 			assertEquals(c1.getName(), db.simplify("@{-1}"));
 			assertEquals("newbranch", db.simplify("@{-2}"));
 			assertEquals("master", db.simplify("@{-3}"));
 
 			// chained expression
 			try {
 				// Cannot refer to reflog of detached head
 				db.resolve("@{-1}@{0}");
 				fail();
 			} catch (RevisionSyntaxException e) {
 				// good
 			}
 			assertEquals(c1.getName(), db.resolve("@{-2}@{0}").getName());
 
 			assertEquals(c2.getName(), db.resolve("@{-3}@{0}").getName());
 		}
 	}
 
 	@Test
 	public void resolveDate() throws Exception {
 		try (Git git = new Git(db)) {
 			writeTrashFile("file.txt", "content");
 			git.add().addFilepattern("file.txt").call();
 			git.commit().setMessage("create file").call();
 			try {
 				db.resolve("master@{yesterday}");
 				fail("Exception not thrown");
 			} catch (RevisionSyntaxException e) {
 				assertNotNull(e);
 			}
 		}
 	}
 }