content: package io.activej.ot.uplink;
  
  import io.activej.ot.OTCommit;
  import io.activej.ot.exception.GraphExhaustedException;
  import io.activej.ot.uplink.AsyncOTUplink.FetchData;
  import io.activej.ot.utils.OTGraphBuilder;
  import io.activej.ot.utils.StubOTRepository;
  import io.activej.ot.utils.TestOp;
  import io.activej.ot.utils.TestOpOTState;
  import io.activej.reactor.Reactor;
  import io.activej.test.rules.EventloopRule;
  import org.jetbrains.annotations.Nullable;
  import org.junit.Before;
  import org.junit.ClassRule;
  import org.junit.Test;
  
  import java.util.List;
  import java.util.Set;
  import java.util.function.Consumer;
  
  import static io.activej.ot.OTCommit.ofRoot;
  import static io.activej.ot.utils.Utils.add;
  import static io.activej.ot.utils.Utils.createTestOp;
  import static io.activej.promise.TestUtils.await;
  import static io.activej.promise.TestUtils.awaitException;
  import static org.hamcrest.CoreMatchers.instanceOf;
  import static org.hamcrest.MatcherAssert.assertThat;
  import static org.junit.Assert.assertEquals;
  
  public class OTUplinkTest {
  	private static final TestOpOTState state = new TestOpOTState();
  
  	@ClassRule
  	public static final EventloopRule eventloopRule = new EventloopRule();
  
  	private final StubOTRepository<Integer, TestOp> REPOSITORY = StubOTRepository.create();
  
  	private AsyncOTUplink<Integer, TestOp, OTCommit<Integer, TestOp>> node;
  
  	@Before
  	public void setUp() {
  		REPOSITORY.reset();
  		node = OTUplink.create(Reactor.getCurrentReactor(), REPOSITORY, createTestOp());
  		resetRepo(null);
  
  	}
  
  	@Test
  	public void testFetchLinearGraph() {
  		REPOSITORY.setGraph(g -> {
  			g.add(0, 1, add(1));
  			g.add(1, 2, add(2));
  			g.add(2, 3, add(3));
  			g.add(3, 4, add(4));
  			g.add(4, 5, add(5));
  			g.add(5, 6, add(6));
  		});
  
  		FetchData<Integer, TestOp> fetchData1 = await(node.fetch(0));
  		assertFetchData(6, 7, 21, fetchData1);
  
  		FetchData<Integer, TestOp> fetchData2 = await(node.fetch(3));
  		assertFetchData(6, 7, 15, fetchData2);
  	}
  
  	@Test
  	public void testFetch2BranchesGraph() {
  		resetRepo(g -> {
  			g.add(0, 1, add(1));
  			g.add(1, 2, add(2));
  			g.add(2, 3, add(3));
  
  			g.add(0, 4, add(4));
  			g.add(4, 5, add(5));
  		});
  
  		FetchData<Integer, TestOp> fetchData1 = await(node.fetch(0));
  		assertFetchData(3, 4, 6, fetchData1);
  
  		resetRepo(g -> {
  			g.add(0, 1, add(1));
  			g.add(1, 2, add(2));
  			g.add(2, 3, add(3));
  
  			g.add(0, 4, add(4));
  			g.add(4, 5, add(5));
  		});
  
  		FetchData<Integer, TestOp> fetchData2 = await(node.fetch(1));
  		assertFetchData(3, 4, 5, fetchData2);
  
  		resetRepo(g -> {
  			g.add(0, 1, add(1));
  			g.add(1, 2, add(2));
  			g.add(2, 3, add(3));
  
  			g.add(0, 4, add(4));
  			g.add(4, 5, add(5));
  		});
  
  		FetchData<Integer, TestOp> fetchData3 = await(node.fetch(4));
  		assertFetchData(5, 3, 5, fetchData3);
  	}
  
  	@Test
  	public void testFetchSplittingGraph() {
  		resetRepo(g -> {
  			g.add(0, 1, add(1));
  			g.add(1, 2, add(2));
  			g.add(2, 3, add(3));
  
  			g.add(0, 4, add(4));
  			g.add(4, 5, add(5));
  
  			g.add(3, 6, add(9));
  			g.add(5, 6, add(6));
  
  			g.add(6, 7, add(7));
  		});
  
  		FetchData<Integer, TestOp> fetchData1 = await(node.fetch(0));
  		assertFetchData(7, 6, 22, fetchData1);
  
  		resetRepo(g -> {
  			g.add(0, 1, add(1));
  			g.add(1, 2, add(2));
  			g.add(2, 3, add(3));
  
  			g.add(0, 4, add(4));
  			g.add(4, 5, add(5));
  
  			g.add(3, 6, add(9));
  			g.add(5, 6, add(6));
  
  			g.add(6, 7, add(7));
  		});
  
  		FetchData<Integer, TestOp> fetchData2 = await(node.fetch(1));
  		assertFetchData(7, 6, 21, fetchData2);
  
  		resetRepo(g -> {
  			g.add(0, 1, add(1));
  			g.add(1, 2, add(2));
  			g.add(2, 3, add(3));
  
  			g.add(0, 4, add(4));
  			g.add(4, 5, add(5));
  
  			g.add(3, 6, add(9));
  			g.add(5, 6, add(6));
  
  			g.add(6, 7, add(7));
  		});
  
  		FetchData<Integer, TestOp> fetchData3 = await(node.fetch(4));
  		assertFetchData(7, 6, 18, fetchData3);
  	}
  
  	@Test
  	public void testFetchInvalidRevision() {
  		Exception exception = awaitException(node.fetch(100));
  		assertThat(exception, instanceOf(GraphExhaustedException.class));
  	}
  
  	@Test
  	public void testCheckoutEmptyGraph() {
  		FetchData<Integer, TestOp> fetchData = await(node.checkout());
  		assertFetchData(0, 1, 0, fetchData);
  	}
  
  	@Test
  	public void testCheckoutLinearGraph() {
  		REPOSITORY.setGraph(g -> {
  			g.add(0, 1, add(1));
  			g.add(1, 2, add(2));
  			g.add(2, 3, add(3));
  			g.add(3, 4, add(4));
  			g.add(4, 5, add(5));
  			g.add(5, 6, add(6));
  		});
  
  		FetchData<Integer, TestOp> fetchData = await(node.checkout());
  		assertFetchData(6, 7, 21, fetchData);
  	}
  
  /*
  	@Test
  	public void testCheckout2BranchesGraph() {
  		REPOSITORY.revisionIdSupplier = () -> 6; // id of merge commit
  		REPOSITORY.setGraph(g -> {
  			g.add(0, 1, add(1));
  			g.add(1, 2, add(2));
  			g.add(2, 3, add(3));
  
  			g.add(0, 4, add(4));
  			g.add(4, 5, add(5));
  		});
  
  		FetchData<Integer, TestOp> fetchData = await(node.checkout());
  		assertFetchData(6, 5, 15, fetchData);
  
  		// Additional snapshot in branch1
  		REPOSITORY.saveSnapshot(4, singletonList(add(4)));
  
  		FetchData<Integer, TestOp> fetchData2 = await(node.checkout());
  		assertFetchData(6, 5, 15, fetchData2);
  
  		// Additional snapshot in branch2
  		REPOSITORY.saveSnapshot(1, singletonList(add(1)));
  
  		FetchData<Integer, TestOp> fetchData3 = await(node.checkout());
  		assertFetchData(6, 5, 15, fetchData3);
  
  	}
  */
  
  	private static void assertFetchData(Integer expectedId, long expectedLevel, Integer expectedState, FetchData<Integer, TestOp> fetchData) {
  		assertEquals(expectedId, fetchData.commitId());
  		assertEquals(expectedLevel, fetchData.level());
  		state.init();
  		fetchData.diffs().forEach(state::apply);
  		assertEquals(expectedState, (Integer) state.getValue());
  	}
  
  	private void resetRepo(@Nullable Consumer<OTGraphBuilder<Integer, TestOp>> builder) {
  		// Initializing repo
  		REPOSITORY.reset();
  		REPOSITORY.doPushAndUpdateHeads(Set.of(ofRoot(0)));
  		await(REPOSITORY.saveSnapshot(0, List.of()));
  
  		if (builder != null) {
  			REPOSITORY.setGraph(builder);
  		}
  	}
  
  }
  