/*
 *  Copyright (c) 2022 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#include "test/pc/e2e/analyzer/video/names_collection.h"

#include <cstddef>
#include <optional>
#include <string>
#include <vector>

#include "test/gmock.h"
#include "test/gtest.h"

namespace webrtc {
namespace {

using ::testing::Eq;
using ::testing::Ne;

TEST(NamesCollectionTest, NamesFromCtorHasUniqueIndexes) {
  NamesCollection collection(std::vector<std::string>{"alice", "bob"});

  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(2)));
  EXPECT_TRUE(collection.HasName("alice"));
  EXPECT_THAT(collection.name(collection.index("alice")), Eq("alice"));

  EXPECT_TRUE(collection.HasName("bob"));
  EXPECT_THAT(collection.name(collection.index("bob")), Eq("bob"));

  EXPECT_THAT(collection.index("bob"), Ne(collection.index("alice")));
}

TEST(NamesCollectionTest, AddedNamesHasIndexes) {
  NamesCollection collection(std::vector<std::string>{});
  collection.AddIfAbsent("alice");

  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(1)));
  EXPECT_TRUE(collection.HasName("alice"));
  EXPECT_THAT(collection.name(collection.index("alice")), Eq("alice"));
}

TEST(NamesCollectionTest, AddBobDoesNotChangeAliceIndex) {
  NamesCollection collection(std::vector<std::string>{"alice"});

  size_t alice_index = collection.index("alice");

  collection.AddIfAbsent("bob");

  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(2)));
  EXPECT_THAT(collection.index("alice"), Eq(alice_index));
  EXPECT_THAT(collection.index("bob"), Ne(alice_index));
}

TEST(NamesCollectionTest, AddAliceSecondTimeDoesNotChangeIndex) {
  NamesCollection collection(std::vector<std::string>{"alice"});

  size_t alice_index = collection.index("alice");

  EXPECT_THAT(collection.AddIfAbsent("alice"), Eq(alice_index));

  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(1)));
  EXPECT_THAT(collection.index("alice"), Eq(alice_index));
}

TEST(NamesCollectionTest, RemoveRemovesFromCollectionButNotIndex) {
  NamesCollection collection(std::vector<std::string>{"alice", "bob"});

  size_t bob_index = collection.index("bob");

  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(2)));

  EXPECT_THAT(collection.RemoveIfPresent("bob"),
              Eq(std::optional<size_t>(bob_index)));

  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(1)));
  EXPECT_FALSE(collection.HasName("bob"));

  EXPECT_THAT(collection.index("bob"), Eq(bob_index));
  EXPECT_THAT(collection.name(bob_index), Eq("bob"));
}

TEST(NamesCollectionTest, RemoveOfAliceDoesNotChangeBobIndex) {
  NamesCollection collection(std::vector<std::string>{"alice", "bob"});

  size_t alice_index = collection.index("alice");
  size_t bob_index = collection.index("bob");

  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(2)));

  EXPECT_THAT(collection.RemoveIfPresent("alice"),
              Eq(std::optional<size_t>(alice_index)));

  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(1)));
  EXPECT_THAT(collection.index("bob"), Eq(bob_index));
  EXPECT_THAT(collection.name(bob_index), Eq("bob"));
}

TEST(NamesCollectionTest, RemoveSecondTimeHasNoEffect) {
  NamesCollection collection(std::vector<std::string>{"bob"});

  size_t bob_index = collection.index("bob");

  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(1)));
  EXPECT_THAT(collection.RemoveIfPresent("bob"),
              Eq(std::optional<size_t>(bob_index)));

  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(0)));
  EXPECT_THAT(collection.RemoveIfPresent("bob"), Eq(std::nullopt));
}

TEST(NamesCollectionTest, RemoveOfNotExistingHasNoEffect) {
  NamesCollection collection(std::vector<std::string>{"bob"});

  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(1)));
  EXPECT_THAT(collection.RemoveIfPresent("alice"), Eq(std::nullopt));
  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(1)));
}

TEST(NamesCollectionTest, AddRemoveAddPreserveTheIndex) {
  NamesCollection collection(std::vector<std::string>{});

  size_t alice_index = collection.AddIfAbsent("alice");
  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(1)));

  EXPECT_THAT(collection.RemoveIfPresent("alice"),
              Eq(std::optional<size_t>(alice_index)));
  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(0)));

  EXPECT_THAT(collection.AddIfAbsent("alice"), Eq(alice_index));
  EXPECT_THAT(collection.index("alice"), Eq(alice_index));
  EXPECT_THAT(collection.size(), Eq(static_cast<size_t>(1)));
}

TEST(NamesCollectionTest, GetKnownSizeReturnsForRemovedNames) {
  NamesCollection collection(std::vector<std::string>{});

  size_t alice_index = collection.AddIfAbsent("alice");
  EXPECT_THAT(collection.GetKnownSize(), Eq(static_cast<size_t>(1)));

  EXPECT_THAT(collection.RemoveIfPresent("alice"),
              Eq(std::optional<size_t>(alice_index)));
  EXPECT_THAT(collection.GetKnownSize(), Eq(static_cast<size_t>(1)));
}

}  // namespace
}  // namespace webrtc