/*
 * Copyright (C) 2010 Google Inc. All rights reserved.
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 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
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 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
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// Tests for the red-black tree class.

#include "third_party/blink/renderer/platform/wtf/pod_red_black_tree.h"

#include "testing/gtest/include/gtest/gtest.h"
#include "third_party/blink/renderer/platform/wtf/pod_tree_test_helpers.h"
#include "third_party/blink/renderer/platform/wtf/vector.h"

namespace blink {

using tree_test_helpers::InitRandom;
using tree_test_helpers::NextRandom;

TEST(PodRedBlackTreeTest, TestSingleElementInsertion) {
  PodRedBlackTree<int> tree;
  tree.Add(5);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(5));
}

TEST(PodRedBlackTreeTest, TestMultipleElementInsertion) {
  PodRedBlackTree<int> tree;
  tree.Add(4);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(4));
  tree.Add(3);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(3));
  tree.Add(5);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(5));
  EXPECT_TRUE(tree.Contains(4));
  EXPECT_TRUE(tree.Contains(3));
}

TEST(PodRedBlackTreeTest, TestDuplicateElementInsertion) {
  PodRedBlackTree<int> tree;
  tree.Add(3);
  ASSERT_TRUE(tree.CheckInvariants());
  tree.Add(3);
  ASSERT_TRUE(tree.CheckInvariants());
  tree.Add(3);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(3));
}

TEST(PodRedBlackTreeTest, TestSingleElementInsertionAndDeletion) {
  PodRedBlackTree<int> tree;
  tree.Add(5);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(5));
  tree.Remove(5);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_FALSE(tree.Contains(5));
}

TEST(PodRedBlackTreeTest, TestMultipleElementInsertionAndDeletion) {
  PodRedBlackTree<int> tree;
  tree.Add(4);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(4));
  tree.Add(3);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(3));
  tree.Add(5);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(5));
  EXPECT_TRUE(tree.Contains(4));
  EXPECT_TRUE(tree.Contains(3));
  tree.Remove(4);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(3));
  EXPECT_FALSE(tree.Contains(4));
  EXPECT_TRUE(tree.Contains(5));
  tree.Remove(5);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(3));
  EXPECT_FALSE(tree.Contains(4));
  EXPECT_FALSE(tree.Contains(5));
}

TEST(PodRedBlackTreeTest, TestDuplicateElementInsertionAndDeletion) {
  PodRedBlackTree<int> tree;
  tree.Add(3);
  ASSERT_TRUE(tree.CheckInvariants());
  tree.Add(3);
  ASSERT_TRUE(tree.CheckInvariants());
  tree.Add(3);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(3));
  tree.Remove(3);
  ASSERT_TRUE(tree.CheckInvariants());
  tree.Remove(3);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_TRUE(tree.Contains(3));
  tree.Remove(3);
  ASSERT_TRUE(tree.CheckInvariants());
  EXPECT_FALSE(tree.Contains(3));
}

TEST(PodRedBlackTreeTest, FailingInsertionRegressionTest1) {
  // These numbers came from a previously-failing randomized test run.
  PodRedBlackTree<int> tree;
  tree.Add(5113);
  ASSERT_TRUE(tree.CheckInvariants());
  tree.Add(4517);
  ASSERT_TRUE(tree.CheckInvariants());
  tree.Add(3373);
  ASSERT_TRUE(tree.CheckInvariants());
  tree.Add(9307);
  ASSERT_TRUE(tree.CheckInvariants());
  tree.Add(7077);
  ASSERT_TRUE(tree.CheckInvariants());
}

namespace {
void InsertionAndDeletionTest(const int32_t seed, const int tree_size) {
  InitRandom(seed);
  const int maximum_value = tree_size;
  // Build the tree.
  PodRedBlackTree<int> tree;
  Vector<int> values;
  for (int i = 0; i < tree_size; i++) {
    int value = NextRandom(maximum_value);
    tree.Add(value);
    ASSERT_TRUE(tree.CheckInvariants()) << "Test failed for seed " << seed;
    values.push_back(value);
  }
  // Churn the tree's contents.
  for (int i = 0; i < tree_size; i++) {
    // Pick a random value to remove.
    int index = NextRandom(tree_size);
    int value = values[index];
    // Remove this value.
    tree.Remove(value);
    ASSERT_TRUE(tree.CheckInvariants()) << "Test failed for seed " << seed;
    // Replace it with a new one.
    value = NextRandom(maximum_value);
    values[index] = value;
    tree.Add(value);
    ASSERT_TRUE(tree.CheckInvariants()) << "Test failed for seed " << seed;
  }
}
}  // anonymous namespace

TEST(PodRedBlackTreeTest, RandomDeletionAndInsertionRegressionTest1) {
  InsertionAndDeletionTest(12311, 100);
}

}  // namespace blink