/*
 * Copyright (C) 2019, Google LLC.
 * and other copyright owners as documented in the project's IP log.
 *
 * This program and the accompanying materials are made available
 * under the terms of the Eclipse Distribution License v1.0 which
 * accompanies this distribution, is reproduced below, and is
 * available at http://www.eclipse.org/org/documents/edl-v10.php
 *
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or
 * without modification, are permitted provided that the following
 * conditions are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 *
 * - Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the following
 *   disclaimer in the documentation and/or other materials provided
 *   with the distribution.
 *
 * - Neither the name of the Eclipse Foundation, Inc. nor the
 *   names of its contributors may be used to endorse or promote
 *   products derived from this software without specific prior
 *   written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
package org.eclipse.jgit.transport;

import java.io.IOException;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Map;

import org.eclipse.jgit.errors.PackProtocolException;
import org.eclipse.jgit.errors.TransportException;
import org.eclipse.jgit.internal.storage.dfs.DfsGarbageCollector;
import org.eclipse.jgit.internal.storage.dfs.DfsRepositoryDescription;
import org.eclipse.jgit.internal.storage.dfs.InMemoryRepository;
import org.eclipse.jgit.junit.TestRepository;
import org.eclipse.jgit.lib.Ref;
import org.eclipse.jgit.lib.Repository;
import org.eclipse.jgit.revwalk.RevBlob;
import org.eclipse.jgit.revwalk.RevCommit;
import org.eclipse.jgit.transport.UploadPack.RequestValidator;
import org.hamcrest.Matchers;
import org.junit.Before;
import org.junit.Rule;
import org.junit.Test;
import org.junit.rules.ExpectedException;

public abstract class RequestValidatorTestCase {

	@Rule
	public ExpectedException thrown = ExpectedException.none();

	private RevCommit reachableCommit;

	private RevCommit tipAdvertisedCommit;

	private RevCommit tipUnadvertisedCommit;

	private RevCommit unreachableCommit;

	private RevBlob reachableBlob;

	private RevBlob unreachableBlob;

	private InMemoryRepository repo;

	protected abstract RequestValidator createValidator();

	@Before
	public void setUp() throws Exception {
		repo = new InMemoryRepository(new DfsRepositoryDescription());
		try (TestRepository<InMemoryRepository> git = new TestRepository<>(
				repo)) {
			reachableBlob = git.blob("foo");
			reachableCommit = git
					.commit(git.tree(git.file("foo", reachableBlob)));
			tipAdvertisedCommit = git.commit(reachableCommit);
			git.update("advertised", tipAdvertisedCommit);

			tipUnadvertisedCommit = git.commit(reachableCommit);
			git.update("unadvertised", tipUnadvertisedCommit);

			unreachableBlob = git.blob("unreachableFoo");
			unreachableCommit = git
					.commit(git.tree(git.file("foo", unreachableBlob)));
		}
	}

	/**
	 * @return true if a commit reachable from a visible tip (but not directly
	 *         the tip) is valid
	 */
	protected abstract boolean isReachableCommitValid();

	/** @return true if a commit not reachable from any tip is valid */
	protected abstract boolean isUnreachableCommitValid();

	/**
	 * @return true if the commit directly pointed by an advertised ref is valid
	 */
	protected abstract boolean isAdvertisedTipValid();

	/**
	 * @return true if the object directly pointed by a non-advertised ref is
	 *         valid
	 */
	protected abstract boolean isUnadvertisedTipCommitValid();

	// UploadPack doesn't allow to ask for blobs when there is no
	// bitmap. Test both cases separately.
	/**
	 * @return true if a reachable blob is valid (and the repo has bitmaps)
	 */
	protected abstract boolean isReachableBlobValid_withBitmaps();

	/**
	 * @return true if a reachable blob is valid (and the repo does NOT have
	 *         bitmaps)
	 */
	protected abstract boolean isReachableBlobValid_withoutBitmaps();

	/**
	 * @return true if a blob unreachable from any tip is valid
	 */
	protected abstract boolean isUnreachableBlobValid();

	@Test
	public void validateReachableCommitWithBitmaps()
			throws PackProtocolException, IOException {
		if (!isReachableCommitValid()) {
			thrown.expect(TransportException.class);
			thrown.expectMessage(Matchers
					.containsString(
							"want " + reachableCommit.name() + " not valid"));

		}
		createValidator().checkWants(getUploadPack(getRepoWithBitmaps()),
				Arrays.asList(reachableCommit));
	}

	@Test
	public void validateReachableCommitWithoutBitmaps()
			throws PackProtocolException, IOException {
		if (!isReachableCommitValid()) {
			thrown.expect(TransportException.class);
			thrown.expectMessage(Matchers.containsString(
					"want " + reachableCommit.name() + " not valid"));

		}
		createValidator().checkWants(getUploadPack(getRepoWithoutBitmaps()),
				Arrays.asList(reachableCommit));
	}

	@Test
	public void validateAdvertisedTipWithBitmaps()
			throws PackProtocolException, IOException {
		if (!isAdvertisedTipValid()) {
			thrown.expect(TransportException.class);
			thrown.expectMessage(Matchers.containsString(
					"want " + tipAdvertisedCommit.name() + " not valid"));

		}
		createValidator().checkWants(getUploadPack(getRepoWithBitmaps()),
				Arrays.asList(tipAdvertisedCommit));
	}

	@Test
	public void validateAdvertisedTipWithoutBitmaps()
			throws PackProtocolException, IOException {
		if (!isAdvertisedTipValid()) {
			thrown.expect(TransportException.class);
			thrown.expectMessage(Matchers.containsString(
					"want " + tipAdvertisedCommit.name() + " not valid"));

		}
		createValidator().checkWants(getUploadPack(getRepoWithoutBitmaps()),
				Arrays.asList(tipAdvertisedCommit));
	}

	@Test
	public void validateUnadvertisedTipWithBitmaps()
			throws PackProtocolException, IOException {
		if (!isUnadvertisedTipCommitValid()) {
			thrown.expect(TransportException.class);
			thrown.expectMessage(Matchers.containsString(
					"want " + tipUnadvertisedCommit.name() + " not valid"));

		}
		createValidator().checkWants(getUploadPack(getRepoWithBitmaps()),
				Arrays.asList(tipUnadvertisedCommit));
	}

	@Test
	public void validateUnadvertisedTipWithoutBitmaps()
			throws PackProtocolException, IOException {
		if (!isUnadvertisedTipCommitValid()) {
			thrown.expect(TransportException.class);
			thrown.expectMessage(Matchers.containsString(
					"want " + tipUnadvertisedCommit.name() + " not valid"));

		}
		createValidator().checkWants(getUploadPack(getRepoWithoutBitmaps()),
				Arrays.asList(tipUnadvertisedCommit));
	}

	@Test
	public void validateUnreachableCommitWithBitmaps()
			throws PackProtocolException, IOException {
		if (!isUnreachableCommitValid()) {
			thrown.expect(TransportException.class);
			thrown.expectMessage(Matchers.containsString(
					"want " + unreachableCommit.name() + " not valid"));

		}
		createValidator().checkWants(getUploadPack(getRepoWithBitmaps()),
				Arrays.asList(unreachableCommit));
	}

	@Test
	public void validateUnreachableCommitWithoutBitmaps()
			throws PackProtocolException, IOException {
		if (!isUnreachableCommitValid()) {
			thrown.expect(TransportException.class);
			thrown.expectMessage(Matchers.containsString(
					"want " + unreachableCommit.name() + " not valid"));

		}
		createValidator().checkWants(getUploadPack(getRepoWithoutBitmaps()),
				Arrays.asList(unreachableCommit));
	}

	@Test
	public void validateReachableBlobWithBitmaps()
			throws PackProtocolException, IOException {
		if (!isReachableBlobValid_withBitmaps()) {
			thrown.expect(TransportException.class);
			thrown.expectMessage(Matchers.containsString(
					"want " + reachableBlob.name() + " not valid"));
		}
		createValidator().checkWants(getUploadPack(getRepoWithBitmaps()),
				Arrays.asList(reachableBlob));
	}

	@Test
	public void validateReachableBlobWithoutBitmaps()
			throws PackProtocolException, IOException {
		if (!isReachableBlobValid_withoutBitmaps()) {
			thrown.expect(TransportException.class);
			thrown.expectMessage(Matchers.containsString(
					"want " + reachableBlob.name() + " not valid"));
		}
		createValidator().checkWants(getUploadPack(getRepoWithoutBitmaps()),
				Arrays.asList(reachableBlob));
	}

	@Test
	public void validateUnreachableBlobWithBitmaps()
			throws PackProtocolException, IOException {
		if (!isUnreachableBlobValid()) {
			thrown.expect(TransportException.class);
			thrown.expectMessage(Matchers.containsString(
					"want " + unreachableBlob.name() + " not valid"));
		}
		createValidator().checkWants(getUploadPack(getRepoWithBitmaps()),
				Arrays.asList(unreachableBlob));
	}

	@Test
	public void validateUnreachableBlobWithoutBitmaps()
			throws PackProtocolException, IOException {
		if (!isUnreachableBlobValid()) {
			thrown.expect(TransportException.class);
			thrown.expectMessage(Matchers.containsString(
					"want " + unreachableBlob.name() + " not valid"));
		}
		createValidator().checkWants(getUploadPack(getRepoWithoutBitmaps()),
				Arrays.asList(unreachableBlob));
	}

	private UploadPack getUploadPack(Repository repository) throws IOException {
		UploadPack uploadPack = new UploadPack(repository);

		Ref advertisedRef = repo.getRefDatabase().findRef("advertised");
		Map<String, Ref> advertisedRefs = new HashMap<>();
		advertisedRefs.put(advertisedRef.getName(), advertisedRef);

		uploadPack.setAdvertisedRefs(advertisedRefs);
		return uploadPack;
	}

	private Repository getRepoWithBitmaps() throws IOException {
		new DfsGarbageCollector(repo).pack(null);
		repo.scanForRepoChanges();
		return repo;
	}

	private Repository getRepoWithoutBitmaps() {
		return repo;
	}
}