/*
 * Copyright (C) 2008, Google Inc.
 * 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
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 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
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package org.eclipse.jgit.treewalk;

import static org.eclipse.jgit.lib.FileMode.REGULAR_FILE;
import static org.eclipse.jgit.lib.FileMode.TREE;
import static org.junit.Assert.assertEquals;
import static org.junit.Assert.assertFalse;
import static org.junit.Assert.assertTrue;

import org.eclipse.jgit.dircache.DirCache;
import org.eclipse.jgit.dircache.DirCacheBuilder;
import org.eclipse.jgit.dircache.DirCacheEntry;
import org.eclipse.jgit.dircache.DirCacheIterator;
import org.eclipse.jgit.junit.RepositoryTestCase;
import org.eclipse.jgit.lib.FileMode;
import org.junit.Test;

public class PostOrderTreeWalkTest extends RepositoryTestCase {
	@Test
	public void testInitialize_NoPostOrder() throws Exception {
		try (final TreeWalk tw = new TreeWalk(db)) {
			assertFalse(tw.isPostOrderTraversal());
		}
	}

	@Test
	public void testInitialize_TogglePostOrder() throws Exception {
		try (final TreeWalk tw = new TreeWalk(db)) {
			assertFalse(tw.isPostOrderTraversal());
			tw.setPostOrderTraversal(true);
			assertTrue(tw.isPostOrderTraversal());
			tw.setPostOrderTraversal(false);
			assertFalse(tw.isPostOrderTraversal());
		}
	}

	@Test
	public void testResetDoesNotAffectPostOrder() throws Exception {
		try (final TreeWalk tw = new TreeWalk(db)) {
			tw.setPostOrderTraversal(true);
			assertTrue(tw.isPostOrderTraversal());
			tw.reset();
			assertTrue(tw.isPostOrderTraversal());

			tw.setPostOrderTraversal(false);
			assertFalse(tw.isPostOrderTraversal());
			tw.reset();
			assertFalse(tw.isPostOrderTraversal());
		}
	}

	@Test
	public void testNoPostOrder() throws Exception {
		final DirCache tree = db.readDirCache();
		final DirCacheBuilder b = tree.builder();

		b.add(makeFile("a"));
		b.add(makeFile("b/c"));
		b.add(makeFile("b/d"));
		b.add(makeFile("q"));

		b.finish();
		assertEquals(4, tree.getEntryCount());

		try (final TreeWalk tw = new TreeWalk(db)) {
			tw.setPostOrderTraversal(false);
			tw.addTree(new DirCacheIterator(tree));

			assertModes("a", REGULAR_FILE, tw);
			assertModes("b", TREE, tw);
			assertTrue(tw.isSubtree());
			assertFalse(tw.isPostChildren());
			tw.enterSubtree();
			assertModes("b/c", REGULAR_FILE, tw);
			assertModes("b/d", REGULAR_FILE, tw);
			assertModes("q", REGULAR_FILE, tw);
		}
	}

	@Test
	public void testWithPostOrder_EnterSubtree() throws Exception {
		final DirCache tree = db.readDirCache();
		final DirCacheBuilder b = tree.builder();

		b.add(makeFile("a"));
		b.add(makeFile("b/c"));
		b.add(makeFile("b/d"));
		b.add(makeFile("q"));

		b.finish();
		assertEquals(4, tree.getEntryCount());

		try (final TreeWalk tw = new TreeWalk(db)) {
			tw.setPostOrderTraversal(true);
			tw.addTree(new DirCacheIterator(tree));

			assertModes("a", REGULAR_FILE, tw);

			assertModes("b", TREE, tw);
			assertTrue(tw.isSubtree());
			assertFalse(tw.isPostChildren());
			tw.enterSubtree();
			assertModes("b/c", REGULAR_FILE, tw);
			assertModes("b/d", REGULAR_FILE, tw);

			assertModes("b", TREE, tw);
			assertTrue(tw.isSubtree());
			assertTrue(tw.isPostChildren());

			assertModes("q", REGULAR_FILE, tw);
		}
	}

	@Test
	public void testWithPostOrder_NoEnterSubtree() throws Exception {
		final DirCache tree = db.readDirCache();
		final DirCacheBuilder b = tree.builder();

		b.add(makeFile("a"));
		b.add(makeFile("b/c"));
		b.add(makeFile("b/d"));
		b.add(makeFile("q"));

		b.finish();
		assertEquals(4, tree.getEntryCount());

		try (final TreeWalk tw = new TreeWalk(db)) {
			tw.setPostOrderTraversal(true);
			tw.addTree(new DirCacheIterator(tree));

			assertModes("a", REGULAR_FILE, tw);

			assertModes("b", TREE, tw);
			assertTrue(tw.isSubtree());
			assertFalse(tw.isPostChildren());

			assertModes("q", REGULAR_FILE, tw);
		}
	}

	private DirCacheEntry makeFile(final String path) throws Exception {
		return createEntry(path, REGULAR_FILE);
	}

	private static void assertModes(final String path, final FileMode mode0,
			final TreeWalk tw) throws Exception {
		assertTrue("has " + path, tw.next());
		assertEquals(path, tw.getPathString());
		assertEquals(mode0, tw.getFileMode(0));
	}
}