Implement receiving remote task.

Test: atest RemoteAccessServiceUnitTest
Bug: 241483300
Change-Id: I3d7f54f154beebba1bb1bdb7640dfe973ad012e4
diff --git a/automotive/remoteaccess/impl/default/client/include/RemoteAccessService.h b/automotive/remoteaccess/impl/default/client/include/RemoteAccessService.h
index f060b6c..806440a 100644
--- a/automotive/remoteaccess/impl/default/client/include/RemoteAccessService.h
+++ b/automotive/remoteaccess/impl/default/client/include/RemoteAccessService.h
@@ -19,6 +19,7 @@
 #include <aidl/android/hardware/automotive/remoteaccess/ApState.h>
 #include <aidl/android/hardware/automotive/remoteaccess/BnRemoteAccess.h>
 #include <aidl/android/hardware/automotive/remoteaccess/IRemoteTaskCallback.h>
+#include <android-base/thread_annotations.h>
 #include <wakeup_client.grpc.pb.h>
 
 #include <string>
@@ -32,7 +33,9 @@
 class RemoteAccessService
     : public aidl::android::hardware::automotive::remoteaccess::BnRemoteAccess {
   public:
-    RemoteAccessService(WakeupClient::StubInterface* grpcStub);
+    explicit RemoteAccessService(WakeupClient::StubInterface* grpcStub);
+
+    ~RemoteAccessService();
 
     ndk::ScopedAStatus getDeviceId(std::string* deviceId) override;
 
@@ -49,12 +52,29 @@
             const aidl::android::hardware::automotive::remoteaccess::ApState& newState) override;
 
   private:
-    WakeupClient::StubInterface* mGrpcStub;
-    std::shared_ptr<aidl::android::hardware::automotive::remoteaccess::IRemoteTaskCallback>
-            mRemoteTaskCallback;
-    std::thread mThread;
+    // For testing.
+    friend class RemoteAccessServiceUnitTest;
 
-    void taskLoop();
+    WakeupClient::StubInterface* mGrpcStub;
+    std::thread mThread;
+    std::mutex mLock;
+    std::condition_variable mCv;
+    std::shared_ptr<aidl::android::hardware::automotive::remoteaccess::IRemoteTaskCallback>
+            mRemoteTaskCallback GUARDED_BY(mLock);
+    std::unique_ptr<grpc::ClientContext> mGetRemoteTasksContext GUARDED_BY(mLock);
+    // Associated with mCv to notify the task loop to stop waiting and exit.
+    bool mTaskWaitStopped GUARDED_BY(mLock);
+    // A mutex to make sure startTaskLoop does not overlap with stopTaskLoop.
+    std::mutex mStartStopTaskLoopLock;
+    bool mTaskLoopRunning GUARDED_BY(mStartStopTaskLoopLock);
+    // Default wait time before retry connecting to remote access client is 10s.
+    size_t mRetryWaitInMs = 10'000;
+
+    void runTaskLoop();
+    void maybeStartTaskLoop();
+    void maybeStopTaskLoop();
+
+    void setRetryWaitInMs(size_t retryWaitInMs) { mRetryWaitInMs = retryWaitInMs; }
 };
 
 }  // namespace remoteaccess
diff --git a/automotive/remoteaccess/impl/default/client/src/RemoteAccessService.cpp b/automotive/remoteaccess/impl/default/client/src/RemoteAccessService.cpp
index f567113..6b97840 100644
--- a/automotive/remoteaccess/impl/default/client/src/RemoteAccessService.cpp
+++ b/automotive/remoteaccess/impl/default/client/src/RemoteAccessService.cpp
@@ -31,23 +31,111 @@
 
 using ::aidl::android::hardware::automotive::remoteaccess::ApState;
 using ::aidl::android::hardware::automotive::remoteaccess::IRemoteTaskCallback;
+using ::android::base::ScopedLockAssertion;
 using ::grpc::ClientContext;
-using ::grpc::ClientReader;
+using ::grpc::ClientReaderInterface;
 using ::grpc::Status;
 using ::grpc::StatusCode;
 using ::ndk::ScopedAStatus;
 
 const std::string WAKEUP_SERVICE_NAME = "com.google.vehicle.wakeup";
 
+std::vector<uint8_t> stringToBytes(const std::string& s) {
+    const char* data = s.data();
+    return std::vector<uint8_t>(data, data + s.size());
+}
+
+ScopedAStatus rpcStatusToScopedAStatus(const Status& status, const std::string& errorMsg) {
+    return ScopedAStatus::fromServiceSpecificErrorWithMessage(
+            status.error_code(), (errorMsg + ", error: " + status.error_message()).c_str());
+}
+
 }  // namespace
 
 RemoteAccessService::RemoteAccessService(WakeupClient::StubInterface* grpcStub)
-    : mGrpcStub(grpcStub) {
-    // mThread = std::thread([this]() { taskLoop(); });
+    : mGrpcStub(grpcStub){};
+
+RemoteAccessService::~RemoteAccessService() {
+    maybeStopTaskLoop();
 }
 
-void RemoteAccessService::taskLoop() {
-    // TODO(b/241483300): handle remote tasks.
+void RemoteAccessService::maybeStartTaskLoop() {
+    std::lock_guard<std::mutex> lockGuard(mStartStopTaskLoopLock);
+    if (mTaskLoopRunning) {
+        return;
+    }
+
+    mThread = std::thread([this]() { runTaskLoop(); });
+
+    mTaskLoopRunning = true;
+}
+
+void RemoteAccessService::maybeStopTaskLoop() {
+    std::lock_guard<std::mutex> lockGuard(mStartStopTaskLoopLock);
+    if (!mTaskLoopRunning) {
+        return;
+    }
+
+    {
+        std::lock_guard<std::mutex> lockGuard(mLock);
+        // Try to stop the reading stream.
+        if (mGetRemoteTasksContext) {
+            mGetRemoteTasksContext->TryCancel();
+            mGetRemoteTasksContext.reset();
+        }
+        mTaskWaitStopped = true;
+        mCv.notify_all();
+    }
+    if (mThread.joinable()) {
+        mThread.join();
+    }
+
+    mTaskLoopRunning = false;
+}
+
+void RemoteAccessService::runTaskLoop() {
+    GetRemoteTasksRequest request = {};
+    std::unique_ptr<ClientReaderInterface<GetRemoteTasksResponse>> reader;
+    while (true) {
+        {
+            std::lock_guard<std::mutex> lockGuard(mLock);
+            mGetRemoteTasksContext.reset(new ClientContext());
+            reader = mGrpcStub->GetRemoteTasks(mGetRemoteTasksContext.get(), request);
+        }
+        GetRemoteTasksResponse response;
+        while (reader->Read(&response)) {
+            std::shared_ptr<IRemoteTaskCallback> callback;
+            {
+                std::lock_guard<std::mutex> lockGuard(mLock);
+                callback = mRemoteTaskCallback;
+            }
+            if (callback == nullptr) {
+                continue;
+            }
+            ScopedAStatus callbackStatus = callback->onRemoteTaskRequested(
+                    response.clientid(), stringToBytes(response.data()));
+            if (!callbackStatus.isOk()) {
+                ALOGE("Failed to call onRemoteTaskRequested callback, status: %d, message: %s",
+                      callbackStatus.getStatus(), callbackStatus.getMessage());
+            }
+        }
+        Status status = reader->Finish();
+
+        ALOGE("GetRemoteTasks stream breaks, code: %d, message: %s, sleeping for 10s and retry",
+              status.error_code(), status.error_message().c_str());
+        // The long lasting connection should not return. But if the server returns, retry after
+        // 10s.
+        {
+            std::unique_lock lk(mLock);
+            if (mCv.wait_for(lk, std::chrono::milliseconds(mRetryWaitInMs), [this] {
+                    ScopedLockAssertion lockAssertion(mLock);
+                    return mTaskWaitStopped;
+                })) {
+                // If the stopped flag is set, we are quitting, exit the loop.
+                break;
+            }
+        }
+    }
 }
 
 ScopedAStatus RemoteAccessService::getDeviceId(std::string* deviceId) {
@@ -62,16 +150,32 @@
 
 ScopedAStatus RemoteAccessService::setRemoteTaskCallback(
         [[maybe_unused]] const std::shared_ptr<IRemoteTaskCallback>& callback) {
+    std::lock_guard<std::mutex> lockGuard(mLock);
     mRemoteTaskCallback = callback;
     return ScopedAStatus::ok();
 }
 
 ScopedAStatus RemoteAccessService::clearRemoteTaskCallback() {
+    std::lock_guard<std::mutex> lockGuard(mLock);
     mRemoteTaskCallback.reset();
     return ScopedAStatus::ok();
 }
 
-ScopedAStatus RemoteAccessService::notifyApStateChange([[maybe_unused]] const ApState& newState) {
+ScopedAStatus RemoteAccessService::notifyApStateChange(const ApState& newState) {
+    ClientContext context;
+    NotifyWakeupRequiredRequest request = {};
+    request.set_iswakeuprequired(newState.isWakeupRequired);
+    NotifyWakeupRequiredResponse response = {};
+    Status status = mGrpcStub->NotifyWakeupRequired(&context, request, &response);
+    if (!status.ok()) {
+        return rpcStatusToScopedAStatus(status, "Failed to notify isWakeupRequired");
+    }
+
+    if (newState.isReadyForRemoteTask) {
+        maybeStartTaskLoop();
+    } else {
+        maybeStopTaskLoop();
+    }
     return ScopedAStatus::ok();
 }
 
diff --git a/automotive/remoteaccess/impl/default/test/RemoteAccessServiceUnitTest.cpp b/automotive/remoteaccess/impl/default/test/RemoteAccessServiceUnitTest.cpp
index de25927..11523f6 100644
--- a/automotive/remoteaccess/impl/default/test/RemoteAccessServiceUnitTest.cpp
+++ b/automotive/remoteaccess/impl/default/test/RemoteAccessServiceUnitTest.cpp
@@ -16,15 +16,25 @@
 
 #include "RemoteAccessService.h"
 
+#include <aidl/android/hardware/automotive/remoteaccess/ApState.h>
+#include <aidl/android/hardware/automotive/remoteaccess/BnRemoteTaskCallback.h>
 #include <gmock/gmock.h>
+#include <grpcpp/test/mock_stream.h>
 #include <gtest/gtest.h>
 #include <wakeup_client.grpc.pb.h>
+#include <chrono>
+#include <thread>
 
 namespace android {
 namespace hardware {
 namespace automotive {
 namespace remoteaccess {
 
+using ::android::base::ScopedLockAssertion;
+
+using ::aidl::android::hardware::automotive::remoteaccess::ApState;
+using ::aidl::android::hardware::automotive::remoteaccess::BnRemoteTaskCallback;
+
 using ::grpc::ClientAsyncReaderInterface;
 using ::grpc::ClientAsyncResponseReaderInterface;
 using ::grpc::ClientContext;
@@ -32,8 +42,12 @@
 using ::grpc::ClientReaderInterface;
 using ::grpc::CompletionQueue;
 using ::grpc::Status;
-
+using ::grpc::testing::MockClientReader;
 using ::ndk::ScopedAStatus;
+using ::testing::_;
+using ::testing::DoAll;
+using ::testing::Return;
+using ::testing::SetArgPointee;
 
 class MockGrpcClientStub : public WakeupClient::StubInterface {
   public:
@@ -59,9 +73,37 @@
                  CompletionQueue* cq));
 };
 
+class FakeRemoteTaskCallback : public BnRemoteTaskCallback {
+  public:
+    ScopedAStatus onRemoteTaskRequested(const std::string& clientId,
+                                        const std::vector<uint8_t>& data) override {
+        std::lock_guard<std::mutex> lockGuard(mLock);
+        mDataByClientId[clientId] = data;
+        mTaskCount++;
+        mCv.notify_all();
+        return ScopedAStatus::ok();
+    }
+
+    std::vector<uint8_t> getData(const std::string& clientId) { return mDataByClientId[clientId]; }
+
+    bool wait(size_t taskCount, size_t timeoutInSec) {
+        std::unique_lock<std::mutex> lock(mLock);
+        return mCv.wait_for(lock, std::chrono::seconds(timeoutInSec), [taskCount, this] {
+            ScopedLockAssertion lockAssertion(mLock);
+            return mTaskCount >= taskCount;
+        });
+    }
+
+  private:
+    std::mutex mLock;
+    std::unordered_map<std::string, std::vector<uint8_t>> mDataByClientId GUARDED_BY(mLock);
+    size_t mTaskCount GUARDED_BY(mLock) = 0;
+    std::condition_variable mCv;
+};
+
 class RemoteAccessServiceUnitTest : public ::testing::Test {
   public:
-    RemoteAccessServiceUnitTest() {
+    virtual void SetUp() override {
         mGrpcWakeupClientStub = std::make_unique<MockGrpcClientStub>();
         mService = ndk::SharedRefBase::make<RemoteAccessService>(mGrpcWakeupClientStub.get());
     }
@@ -70,9 +112,12 @@
 
     RemoteAccessService* getService() { return mService.get(); }
 
+    void setRetryWaitInMs(size_t retryWaitInMs) { mService->setRetryWaitInMs(retryWaitInMs); }
+
   private:
     std::unique_ptr<MockGrpcClientStub> mGrpcWakeupClientStub;
     std::shared_ptr<RemoteAccessService> mService;
+    MockClientReader<GetRemoteTasksResponse>* mMockTaskReader;
 };
 
 TEST_F(RemoteAccessServiceUnitTest, TestGetWakeupServiceName) {
@@ -84,6 +129,159 @@
     EXPECT_EQ(serviceName, "com.google.vehicle.wakeup");
 }
 
+TEST_F(RemoteAccessServiceUnitTest, TestNotifyApStateChangeWakeupRequired) {
+    bool isWakeupRequired = false;
+    EXPECT_CALL(*getGrpcWakeupClientStub(), NotifyWakeupRequired)
+            .WillOnce([&isWakeupRequired]([[maybe_unused]] ClientContext* context,
+                                          const NotifyWakeupRequiredRequest& request,
+                                          [[maybe_unused]] NotifyWakeupRequiredResponse* response) {
+                isWakeupRequired = request.iswakeuprequired();
+                return Status();
+            });
+
+    ApState newState = {
+            .isWakeupRequired = true,
+    };
+    ScopedAStatus status = getService()->notifyApStateChange(newState);
+
+    EXPECT_TRUE(status.isOk());
+    EXPECT_TRUE(isWakeupRequired);
+}
+
+TEST_F(RemoteAccessServiceUnitTest, TestGetRemoteTasks) {
+    GetRemoteTasksResponse response1;
+    std::vector<uint8_t> testData = {0xde, 0xad, 0xbe, 0xef};
+    response1.set_clientid("1");
+    response1.set_data(testData.data(), testData.size());
+    GetRemoteTasksResponse response2;
+    response2.set_clientid("2");
+    std::shared_ptr<FakeRemoteTaskCallback> callback =
+            ndk::SharedRefBase::make<FakeRemoteTaskCallback>();
+
+    ON_CALL(*getGrpcWakeupClientStub(), GetRemoteTasksRaw)
+            .WillByDefault(
+                    [response1, response2]([[maybe_unused]] ClientContext* context,
+                                           [[maybe_unused]] const GetRemoteTasksRequest& request) {
+                        // mockReader ownership will be transferred to the client so we don't own it
+                        // here.
+                        MockClientReader<GetRemoteTasksResponse>* mockClientReader =
+                                new MockClientReader<GetRemoteTasksResponse>();
+                        EXPECT_CALL(*mockClientReader, Finish()).WillOnce(Return(Status::OK));
+                        EXPECT_CALL(*mockClientReader, Read(_))
+                                .WillOnce(DoAll(SetArgPointee<0>(response1), Return(true)))
+                                .WillOnce(DoAll(SetArgPointee<0>(response2), Return(true)))
+                                .WillRepeatedly(Return(false));
+                        return mockClientReader;
+                    });
+
+    getService()->setRemoteTaskCallback(callback);
+    // Start the long live connection to receive tasks.
+    ApState newState = {
+            .isReadyForRemoteTask = true,
+    };
+    ASSERT_TRUE(getService()->notifyApStateChange(newState).isOk());
+
+    ASSERT_TRUE(callback->wait(/*taskCount=*/2, /*timeoutInSec=*/10))
+            << "Did not receive enough tasks";
+    EXPECT_EQ(callback->getData("1"), testData);
+    EXPECT_EQ(callback->getData("2"), std::vector<uint8_t>());
+}
+
+TEST_F(RemoteAccessServiceUnitTest, TestGetRemoteTasksRetryConnection) {
+    GetRemoteTasksResponse response;
+    std::shared_ptr<FakeRemoteTaskCallback> callback =
+            ndk::SharedRefBase::make<FakeRemoteTaskCallback>();
+
+    ON_CALL(*getGrpcWakeupClientStub(), GetRemoteTasksRaw)
+            .WillByDefault([response]([[maybe_unused]] ClientContext* context,
+                                      [[maybe_unused]] const GetRemoteTasksRequest& request) {
+                // mockReader ownership will be transferred to the client so we don't own it here.
+                MockClientReader<GetRemoteTasksResponse>* mockClientReader =
+                        new MockClientReader<GetRemoteTasksResponse>();
+                EXPECT_CALL(*mockClientReader, Finish()).WillOnce(Return(Status::OK));
+                // Connection fails after receiving one task. Should retry after some time.
+                EXPECT_CALL(*mockClientReader, Read(_))
+                        .WillOnce(DoAll(SetArgPointee<0>(response), Return(true)))
+                        .WillRepeatedly(Return(false));
+                return mockClientReader;
+            });
+
+    getService()->setRemoteTaskCallback(callback);
+    setRetryWaitInMs(100);
+    // Start the long live connection to receive tasks.
+    ApState newState = {
+            .isReadyForRemoteTask = true,
+    };
+    ASSERT_TRUE(getService()->notifyApStateChange(newState).isOk());
+
+    ASSERT_TRUE(callback->wait(/*taskCount=*/2, /*timeoutInSec=*/10))
+            << "Did not receive enough tasks";
+}
+
+TEST_F(RemoteAccessServiceUnitTest, TestGetRemoteTasksDefaultNotReady) {
+    GetRemoteTasksResponse response1;
+    std::vector<uint8_t> testData = {0xde, 0xad, 0xbe, 0xef};
+    response1.set_clientid("1");
+    response1.set_data(testData.data(), testData.size());
+    GetRemoteTasksResponse response2;
+    response2.set_clientid("2");
+    std::shared_ptr<FakeRemoteTaskCallback> callback =
+            ndk::SharedRefBase::make<FakeRemoteTaskCallback>();
+
+    EXPECT_CALL(*getGrpcWakeupClientStub(), GetRemoteTasksRaw).Times(0);
+
+    // Default state is not ready for remote tasks, so no callback will be called.
+    getService()->setRemoteTaskCallback(callback);
+
+    std::this_thread::sleep_for(std::chrono::milliseconds(100));
+}
+
+TEST_F(RemoteAccessServiceUnitTest, TestGetRemoteTasksNotReadyAfterReady) {
+    GetRemoteTasksResponse response1;
+    std::vector<uint8_t> testData = {0xde, 0xad, 0xbe, 0xef};
+    response1.set_clientid("1");
+    response1.set_data(testData.data(), testData.size());
+    GetRemoteTasksResponse response2;
+    response2.set_clientid("2");
+    std::shared_ptr<FakeRemoteTaskCallback> callback =
+            ndk::SharedRefBase::make<FakeRemoteTaskCallback>();
+
+    ON_CALL(*getGrpcWakeupClientStub(), GetRemoteTasksRaw)
+            .WillByDefault(
+                    [response1, response2]([[maybe_unused]] ClientContext* context,
+                                           [[maybe_unused]] const GetRemoteTasksRequest& request) {
+                        // mockReader ownership will be transferred to the client so we don't own it
+                        // here.
+                        MockClientReader<GetRemoteTasksResponse>* mockClientReader =
+                                new MockClientReader<GetRemoteTasksResponse>();
+                        EXPECT_CALL(*mockClientReader, Finish()).WillOnce(Return(Status::OK));
+                        EXPECT_CALL(*mockClientReader, Read(_))
+                                .WillOnce(DoAll(SetArgPointee<0>(response1), Return(true)))
+                                .WillOnce(DoAll(SetArgPointee<0>(response2), Return(true)))
+                                .WillRepeatedly(Return(false));
+                        return mockClientReader;
+                    });
+    // Should only be called once when is is ready for remote task.
+    EXPECT_CALL(*getGrpcWakeupClientStub(), GetRemoteTasksRaw).Times(1);
+
+    getService()->setRemoteTaskCallback(callback);
+    setRetryWaitInMs(100);
+    // Start the long live connection to receive tasks.
+    ApState newState = {
+            .isReadyForRemoteTask = true,
+    };
+    ASSERT_TRUE(getService()->notifyApStateChange(newState).isOk());
+    ASSERT_TRUE(callback->wait(/*taskCount=*/2, /*timeoutInSec=*/10))
+            << "Did not receive enough tasks";
+
+    // Stop the long live connection.
+    newState.isReadyForRemoteTask = false;
+    ASSERT_TRUE(getService()->notifyApStateChange(newState).isOk());
+
+    // Wait for the retry delay, but the loop should already exit.
+    std::this_thread::sleep_for(std::chrono::milliseconds(150));
+}
+
 }  // namespace remoteaccess
 }  // namespace automotive
 }  // namespace hardware