Add Cast app availability tracker

This change ports the CastAppAvailabilityTracker from Chromium in
preparation for the app discovery service.

Bug: openscreen:60
Change-Id: Id450f6f616a35ae1c1959fa3326593370daf072c
Reviewed-on: https://chromium-review.googlesource.com/c/openscreen/+/2029249
Commit-Queue: Brandon Tolsch <btolsch@chromium.org>
Reviewed-by: Takumi Fujimoto <takumif@chromium.org>

1 files changed, 159 insertions, 0 deletions

diff --git a/cast/sender/cast_app_availability_tracker_unittest.cc b/cast/sender/cast_app_availability_tracker_unittest.cc
new file mode 100644
index 00000000..b45d3563
--- /dev/null
+++ b/cast/sender/cast_app_availability_tracker_unittest.cc
@@ -0,0 +1,159 @@
+// Copyright 2020 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "cast/sender/cast_app_availability_tracker.h"
+
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+#include "platform/test/fake_clock.h"
+
+namespace openscreen {
+namespace cast {
+namespace {
+
+using ::testing::UnorderedElementsAreArray;
+
+MATCHER_P(CastMediaSourcesEqual, expected, "") {
+  if (expected.size() != arg.size())
+    return false;
+  return std::equal(
+      expected.begin(), expected.end(), arg.begin(),
+      [](const CastMediaSource& source1, const CastMediaSource& source2) {
+        return source1.source_id() == source2.source_id();
+      });
+}
+
+}  // namespace
+
+class CastAppAvailabilityTrackerTest : public ::testing::Test {
+ public:
+  CastAppAvailabilityTrackerTest() : clock_(Clock::now()) {}
+  ~CastAppAvailabilityTrackerTest() override = default;
+
+  Clock::time_point Now() const { return clock_.now(); }
+
+ protected:
+  FakeClock clock_;
+  CastAppAvailabilityTracker tracker_;
+};
+
+TEST_F(CastAppAvailabilityTrackerTest, RegisterSource) {
+  CastMediaSource source1("cast:AAA?clientId=1", {"AAA"});
+  CastMediaSource source2("cast:AAA?clientId=2", {"AAA"});
+
+  std::vector<std::string> expected_app_ids = {"AAA"};
+  EXPECT_EQ(expected_app_ids, tracker_.RegisterSource(source1));
+
+  EXPECT_EQ(std::vector<std::string>{}, tracker_.RegisterSource(source1));
+  EXPECT_EQ(std::vector<std::string>{}, tracker_.RegisterSource(source2));
+
+  tracker_.UnregisterSource(source1);
+  tracker_.UnregisterSource(source2);
+
+  EXPECT_EQ(expected_app_ids, tracker_.RegisterSource(source1));
+  EXPECT_EQ(expected_app_ids, tracker_.GetRegisteredApps());
+}
+
+TEST_F(CastAppAvailabilityTrackerTest, RegisterSourceReturnsMultipleAppIds) {
+  CastMediaSource source1("urn:x-org.chromium.media:source:tab:1",
+                          {"0F5096E8", "85CDB22F"});
+
+  // Mirorring app ids.
+  std::vector<std::string> expected_app_ids = {"0F5096E8", "85CDB22F"};
+  EXPECT_THAT(tracker_.RegisterSource(source1),
+              UnorderedElementsAreArray(expected_app_ids));
+  EXPECT_THAT(tracker_.GetRegisteredApps(),
+              UnorderedElementsAreArray(expected_app_ids));
+}
+
+TEST_F(CastAppAvailabilityTrackerTest, MultipleAppIdsAlreadyTrackingOne) {
+  // One of the mirroring app IDs.
+  CastMediaSource source1("cast:0F5096E8?clientId=123", {"0F5096E8"});
+
+  std::vector<std::string> new_app_ids = {"0F5096E8"};
+  std::vector<std::string> registered_app_ids = {"0F5096E8"};
+  EXPECT_EQ(new_app_ids, tracker_.RegisterSource(source1));
+  EXPECT_EQ(registered_app_ids, tracker_.GetRegisteredApps());
+
+  CastMediaSource source2("urn:x-org.chromium.media:source:tab:1",
+                          {"0F5096E8", "85CDB22F"});
+
+  new_app_ids = {"85CDB22F"};
+  registered_app_ids = {"0F5096E8", "85CDB22F"};
+
+  EXPECT_EQ(new_app_ids, tracker_.RegisterSource(source2));
+  EXPECT_THAT(tracker_.GetRegisteredApps(),
+              UnorderedElementsAreArray(registered_app_ids));
+}
+
+TEST_F(CastAppAvailabilityTrackerTest, UpdateAppAvailability) {
+  CastMediaSource source1("cast:AAA?clientId=1", {"AAA"});
+  CastMediaSource source2("cast:AAA?clientId=2", {"AAA"});
+  CastMediaSource source3("cast:BBB?clientId=3", {"BBB"});
+
+  tracker_.RegisterSource(source3);
+
+  // |source3| not affected.
+  EXPECT_THAT(
+      tracker_.UpdateAppAvailability(
+          "deviceId1", "AAA", {AppAvailabilityResult::kAvailable, Now()}),
+      CastMediaSourcesEqual(std::vector<CastMediaSource>()));
+
+  std::vector<std::string> devices_1 = {"deviceId1"};
+  std::vector<std::string> devices_1_2 = {"deviceId1", "deviceId2"};
+  std::vector<CastMediaSource> sources_1 = {source1};
+  std::vector<CastMediaSource> sources_1_2 = {source1, source2};
+
+  // Tracker returns available devices even though sources aren't registered.
+  EXPECT_EQ(devices_1, tracker_.GetAvailableDevices(source1));
+  EXPECT_EQ(devices_1, tracker_.GetAvailableDevices(source2));
+  EXPECT_TRUE(tracker_.GetAvailableDevices(source3).empty());
+
+  tracker_.RegisterSource(source1);
+  // Only |source1| is registered for this app.
+  EXPECT_THAT(
+      tracker_.UpdateAppAvailability(
+          "deviceId2", "AAA", {AppAvailabilityResult::kAvailable, Now()}),
+      CastMediaSourcesEqual(sources_1));
+  EXPECT_THAT(tracker_.GetAvailableDevices(source1),
+              UnorderedElementsAreArray(devices_1_2));
+  EXPECT_THAT(tracker_.GetAvailableDevices(source2),
+              UnorderedElementsAreArray(devices_1_2));
+  EXPECT_TRUE(tracker_.GetAvailableDevices(source3).empty());
+
+  tracker_.RegisterSource(source2);
+  EXPECT_THAT(
+      tracker_.UpdateAppAvailability(
+          "deviceId2", "AAA", {AppAvailabilityResult::kUnavailable, Now()}),
+      CastMediaSourcesEqual(sources_1_2));
+  EXPECT_EQ(devices_1, tracker_.GetAvailableDevices(source1));
+  EXPECT_EQ(devices_1, tracker_.GetAvailableDevices(source2));
+  EXPECT_TRUE(tracker_.GetAvailableDevices(source3).empty());
+}
+
+TEST_F(CastAppAvailabilityTrackerTest, RemoveResultsForDevice) {
+  CastMediaSource source1("cast:AAA?clientId=1", {"AAA"});
+
+  tracker_.UpdateAppAvailability("deviceId1", "AAA",
+                                 {AppAvailabilityResult::kAvailable, Now()});
+  EXPECT_EQ(AppAvailabilityResult::kAvailable,
+            tracker_.GetAvailability("deviceId1", "AAA").availability);
+
+  std::vector<std::string> expected_device_ids = {"deviceId1"};
+  EXPECT_EQ(expected_device_ids, tracker_.GetAvailableDevices(source1));
+
+  // Unrelated device ID.
+  tracker_.RemoveResultsForDevice("deviceId2");
+  EXPECT_EQ(AppAvailabilityResult::kAvailable,
+            tracker_.GetAvailability("deviceId1", "AAA").availability);
+  EXPECT_EQ(expected_device_ids, tracker_.GetAvailableDevices(source1));
+
+  tracker_.RemoveResultsForDevice("deviceId1");
+  EXPECT_EQ(AppAvailabilityResult::kUnknown,
+            tracker_.GetAvailability("deviceId1", "AAA").availability);
+  EXPECT_EQ(std::vector<std::string>{}, tracker_.GetAvailableDevices(source1));
+}
+
+}  // namespace cast
+}  // namespace openscreen