Implement Fast Pair UI broker

PiperOrigin-RevId: 525184851

fastpair/ui/BUILD

@@ -5,12 +5,15 @@ cc_library(
     srcs = [
         "fast_pair/fast_pair_notification_controller.cc",
         "fast_pair/fast_pair_presenter_impl.cc",
+        "ui_broker_impl.cc",
     ],
     hdrs = [
         "actions.h",
         "fast_pair/fast_pair_notification_controller.h",
         "fast_pair/fast_pair_presenter.h",
         "fast_pair/fast_pair_presenter_impl.h",
+        "ui_broker.h",
+        "ui_broker_impl.h",
     ],
     compatible_with = ["//buildenv/target:non_prod"],
     visibility = [
@@ -23,7 +26,6 @@ cc_library(
         "//internal/base",
         "//internal/platform:logging",
         "@com_google_absl//absl/functional:any_invocable",
-        "@com_google_absl//absl/log:check",
         "@com_google_absl//absl/strings",
     ],
 )
@@ -48,6 +50,7 @@ cc_test(
     srcs = [
         "fast_pair/fast_pair_notification_controller_test.cc",
         "fast_pair/fast_pair_presenter_impl_test.cc",
+        "ui_broker_impl_test.cc",
     ],
     deps = [
         ":fake_fast_pair_ui",

fastpair/ui/ui_broker.h

@@ -0,0 +1,50 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef THIRD_PARTY_NEARBY_FASTPAIR_UI_UI_BROKER_H_
+#define THIRD_PARTY_NEARBY_FASTPAIR_UI_UI_BROKER_H_
+
+#include "fastpair/common/fast_pair_device.h"
+#include "fastpair/ui/actions.h"
+#include "fastpair/ui/fast_pair/fast_pair_notification_controller.h"
+
+namespace nearby {
+namespace fastpair {
+
+// The UIBroker is the entry point for the UI component in the FastPair system.
+// It is responsible for brokering the 'show UI' calls to the correct Presenter
+// implementation, and exposing user actions taken on that UI.
+class UIBroker {
+ public:
+  class Observer {
+   public:
+    virtual ~Observer() = default;
+    virtual void OnDiscoveryAction(const FastPairDevice& device,
+                                   DiscoveryAction action) = 0;
+  };
+
+  virtual ~UIBroker() = default;
+
+  virtual void AddObserver(Observer* observer) = 0;
+  virtual void RemoveObserver(Observer* observer) = 0;
+
+  virtual void ShowDiscovery(
+      const FastPairDevice& device,
+      FastPairNotificationController& notification_controller) = 0;
+};
+
+}  // namespace fastpair
+}  // namespace nearby
+
+#endif  // THIRD_PARTY_NEARBY_FASTPAIR_UI_UI_BROKER_H_

fastpair/ui/ui_broker_impl.cc

@@ -0,0 +1,69 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "fastpair/ui/ui_broker_impl.h"
+
+#include <memory>
+
+#include "fastpair/common/fast_pair_device.h"
+#include "fastpair/common/protocol.h"
+#include "fastpair/ui/actions.h"
+#include "fastpair/ui/fast_pair/fast_pair_presenter.h"
+#include "fastpair/ui/fast_pair/fast_pair_presenter_impl.h"
+#include "internal/platform/logging.h"
+
+namespace nearby {
+namespace fastpair {
+
+UIBrokerImpl::UIBrokerImpl()
+    : fast_pair_presenter_(FastPairPresenterImpl::Factory::Create()) {}
+
+void UIBrokerImpl::AddObserver(Observer* observer) {
+  observers_.AddObserver(observer);
+}
+
+void UIBrokerImpl::RemoveObserver(Observer* observer) {
+  observers_.RemoveObserver(observer);
+}
+
+void UIBrokerImpl::ShowDiscovery(
+    const FastPairDevice& device,
+    FastPairNotificationController& notification_controller) {
+  switch (device.GetProtocol()) {
+    case Protocol::kFastPairInitialPairing:
+    case Protocol::kFastPairSubsequentPairing:
+      fast_pair_presenter_->ShowDiscovery(
+          device, notification_controller,
+          [&device, this](DiscoveryAction action) {
+            NEARBY_LOGS(INFO)
+                << __func__ << ": Notify discovery action to all observers.";
+            NotifyDiscoveryAction(device, action);
+          });
+      break;
+    case Protocol::kFastPairRetroactivePairing:
+      NEARBY_LOGS(ERROR)
+          << __func__
+          << ": Retroactive Pairing should not show discovery Halfsheet.";
+      break;
+  }
+}
+
+void UIBrokerImpl::NotifyDiscoveryAction(const FastPairDevice& device,
+                                         DiscoveryAction action) {
+  for (auto& observer : observers_.GetObservers())
+    observer->OnDiscoveryAction(device, action);
+}
+
+}  // namespace fastpair
+}  // namespace nearby

fastpair/ui/ui_broker_impl.h

@@ -0,0 +1,52 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#ifndef THIRD_PARTY_NEARBY_FASTPAIR_UI_BROKER_IMPL_H_
+#define THIRD_PARTY_NEARBY_FASTPAIR_UI_BROKER_IMPL_H_
+
+#include <memory>
+
+#include "fastpair/common/fast_pair_device.h"
+#include "fastpair/ui/actions.h"
+#include "fastpair/ui/fast_pair/fast_pair_presenter.h"
+#include "fastpair/ui/ui_broker.h"
+#include "internal/base/observer_list.h"
+
+namespace nearby {
+namespace fastpair {
+
+class UIBrokerImpl : public UIBroker {
+ public:
+  UIBrokerImpl();
+  UIBrokerImpl(const UIBrokerImpl &) = delete;
+  UIBrokerImpl &operator=(const UIBrokerImpl &) = delete;
+
+  void AddObserver(Observer *observer) override;
+  void RemoveObserver(Observer *observer) override;
+  void ShowDiscovery(
+      const FastPairDevice &device,
+      FastPairNotificationController &notification_controller) override;
+
+ private:
+  void NotifyDiscoveryAction(const FastPairDevice &device,
+                             DiscoveryAction action);
+
+  std::unique_ptr<FastPairPresenter> fast_pair_presenter_;
+  ObserverList<Observer> observers_;
+};
+
+}  // namespace fastpair
+}  // namespace nearby
+
+#endif  // THIRD_PARTY_NEARBY_FASTPAIR_UI_BROKER_IMPL_H_

fastpair/ui/ui_broker_impl_test.cc

@@ -0,0 +1,76 @@
+// Copyright 2023 Google LLC
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     https://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+#include "fastpair/ui/ui_broker_impl.h"
+
+#include <memory>
+#include <string>
+
+#include "gtest/gtest.h"
+#include "fastpair/ui/actions.h"
+#include "fastpair/ui/fast_pair/fake_fast_pair_presenter.h"
+#include "fastpair/ui/fast_pair/fast_pair_notification_controller.h"
+#include "fastpair/ui/ui_broker.h"
+
+namespace nearby {
+namespace fastpair {
+namespace {
+
+constexpr absl::string_view kModelId = "718C17";
+constexpr absl::string_view kAddress = "74:74:46:01:6C:21";
+
+class UIBrokerImplTest : public ::testing::Test, public UIBroker::Observer {
+ protected:
+  UIBrokerImplTest() {
+    presenter_factory_ = std::make_unique<FakeFastPairPresenterFactory>();
+    FastPairPresenterImpl::Factory::SetFactoryForTesting(
+        presenter_factory_.get());
+    ui_broker_ = std::make_unique<UIBrokerImpl>();
+    ui_broker_->AddObserver(this);
+  }
+
+  void OnDiscoveryAction(const FastPairDevice& device,
+                         DiscoveryAction action) override {
+    on_discovery_action_notified_ = true;
+    discovery_action_ = action;
+  }
+
+  std::unique_ptr<UIBroker> ui_broker_;
+  FastPairNotificationController notification_controller_;
+  std::unique_ptr<FakeFastPairPresenterFactory> presenter_factory_;
+  DiscoveryAction discovery_action_;
+  bool on_discovery_action_notified_ = false;
+};
+
+TEST_F(UIBrokerImplTest, ShowDiscovery) {
+  FastPairDevice device(kModelId, kAddress, Protocol::kFastPairInitialPairing);
+  ui_broker_->ShowDiscovery(device, notification_controller_);
+  EXPECT_TRUE(
+      presenter_factory_->fake_fast_pair_presenter()->show_deiscovery());
+  EXPECT_TRUE(on_discovery_action_notified_);
+  EXPECT_EQ(DiscoveryAction::kPairToDevice, discovery_action_);
+}
+
+TEST_F(UIBrokerImplTest, ShowDiscoveryWithoutObserver) {
+  FastPairDevice device(kModelId, kAddress, Protocol::kFastPairInitialPairing);
+  ui_broker_->RemoveObserver(this);
+  ui_broker_->ShowDiscovery(device, notification_controller_);
+  EXPECT_TRUE(
+      presenter_factory_->fake_fast_pair_presenter()->show_deiscovery());
+  EXPECT_FALSE(on_discovery_action_notified_);
+}
+
+}  // namespace
+}  // namespace fastpair
+}  // namespace nearby