// Copyright 2013 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 "mojo/public/cpp/bindings/binding.h"
#include "mojo/public/cpp/bindings/error_handler.h"
#include "mojo/public/cpp/bindings/strong_binding.h"
#include "mojo/public/cpp/environment/environment.h"
#include "mojo/public/cpp/utility/run_loop.h"
#include "mojo/public/interfaces/bindings/tests/math_calculator.mojom.h"
#include "mojo/public/interfaces/bindings/tests/sample_service.mojom.h"
#include "testing/gtest/include/gtest/gtest.h"

namespace mojo {
namespace test {
namespace {

class ErrorObserver : public ErrorHandler {
 public:
  ErrorObserver() : encountered_error_(false) {}

  bool encountered_error() const { return encountered_error_; }

  void OnConnectionError() override { encountered_error_ = true; }

 private:
  bool encountered_error_;
};

template <typename Method, typename Class>
class RunnableImpl {
 public:
  RunnableImpl(Method method, Class instance)
      : method_(method), instance_(instance) {}
  template <typename... Args>
  void Run(Args... args) const {
    (instance_->*method_)(args...);
  }

 private:
  Method method_;
  Class instance_;
};

template <typename Method, typename Class>
RunnableImpl<Method, Class> MakeRunnable(Method method, Class object) {
  return RunnableImpl<Method, Class>(method, object);
}

typedef mojo::Callback<void(double)> CalcCallback;

class MathCalculatorImpl : public InterfaceImpl<math::Calculator> {
 public:
  ~MathCalculatorImpl() override {}

  MathCalculatorImpl() : total_(0.0) {}

  void Clear(const CalcCallback& callback) override {
    total_ = 0.0;
    callback.Run(total_);
  }

  void Add(double value, const CalcCallback& callback) override {
    total_ += value;
    callback.Run(total_);
  }

  void Multiply(double value, const CalcCallback& callback) override {
    total_ *= value;
    callback.Run(total_);
  }

 private:
  double total_;
};

class MathCalculatorUI {
 public:
  explicit MathCalculatorUI(math::CalculatorPtr calculator)
      : calculator_(calculator.Pass()),
        output_(0.0),
        callback_(MakeRunnable(&MathCalculatorUI::Output, this)) {}

  bool WaitForIncomingMethodCall() {
    return calculator_.WaitForIncomingMethodCall();
  }

  bool encountered_error() const { return calculator_.encountered_error(); }

  void Add(double value) { calculator_->Add(value, callback_); }

  void Subtract(double value) { calculator_->Add(-value, callback_); }

  void Multiply(double value) { calculator_->Multiply(value, callback_); }

  void Divide(double value) { calculator_->Multiply(1.0 / value, callback_); }

  double GetOutput() const { return output_; }

 private:
  void Output(double output) { output_ = output; }

  math::CalculatorPtr calculator_;
  double output_;
  Callback<void(double)> callback_;
};

class SelfDestructingMathCalculatorUI {
 public:
  explicit SelfDestructingMathCalculatorUI(math::CalculatorPtr calculator)
      : calculator_(calculator.Pass()), nesting_level_(0) {
    ++num_instances_;
  }

  void BeginTest(bool nested) {
    nesting_level_ = nested ? 2 : 1;
    calculator_->Add(
        1.0, MakeRunnable(&SelfDestructingMathCalculatorUI::Output, this));
  }

  static int num_instances() { return num_instances_; }

  void Output(double value) {
    if (--nesting_level_ > 0) {
      // Add some more and wait for re-entrant call to Output!
      calculator_->Add(
          1.0, MakeRunnable(&SelfDestructingMathCalculatorUI::Output, this));
      RunLoop::current()->RunUntilIdle();
    } else {
      delete this;
    }
  }

 private:
  ~SelfDestructingMathCalculatorUI() { --num_instances_; }

  math::CalculatorPtr calculator_;
  int nesting_level_;
  static int num_instances_;
};

// static
int SelfDestructingMathCalculatorUI::num_instances_ = 0;

class ReentrantServiceImpl : public InterfaceImpl<sample::Service> {
 public:
  ~ReentrantServiceImpl() override {}

  ReentrantServiceImpl() : call_depth_(0), max_call_depth_(0) {}

  int max_call_depth() { return max_call_depth_; }

  void Frobinate(sample::FooPtr foo,
                 sample::Service::BazOptions baz,
                 sample::PortPtr port) override {
    max_call_depth_ = std::max(++call_depth_, max_call_depth_);
    if (call_depth_ == 1) {
      EXPECT_TRUE(WaitForIncomingMethodCall());
    }
    call_depth_--;
  }

  void GetPort(mojo::InterfaceRequest<sample::Port> port) override {}

 private:
  int call_depth_;
  int max_call_depth_;
};

class InterfacePtrTest : public testing::Test {
 public:
  ~InterfacePtrTest() override { loop_.RunUntilIdle(); }

  void PumpMessages() { loop_.RunUntilIdle(); }

 private:
  Environment env_;
  RunLoop loop_;
};

TEST_F(InterfacePtrTest, EndToEnd) {
  math::CalculatorPtr calc;
  BindToProxy(new MathCalculatorImpl(), &calc);

  // Suppose this is instantiated in a process that has pipe1_.
  MathCalculatorUI calculator_ui(calc.Pass());

  calculator_ui.Add(2.0);
  calculator_ui.Multiply(5.0);

  PumpMessages();

  EXPECT_EQ(10.0, calculator_ui.GetOutput());
}

TEST_F(InterfacePtrTest, EndToEnd_Synchronous) {
  math::CalculatorPtr calc;
  MathCalculatorImpl* impl = BindToProxy(new MathCalculatorImpl(), &calc);

  // Suppose this is instantiated in a process that has pipe1_.
  MathCalculatorUI calculator_ui(calc.Pass());

  EXPECT_EQ(0.0, calculator_ui.GetOutput());

  calculator_ui.Add(2.0);
  EXPECT_EQ(0.0, calculator_ui.GetOutput());
  impl->WaitForIncomingMethodCall();
  calculator_ui.WaitForIncomingMethodCall();
  EXPECT_EQ(2.0, calculator_ui.GetOutput());

  calculator_ui.Multiply(5.0);
  EXPECT_EQ(2.0, calculator_ui.GetOutput());
  impl->WaitForIncomingMethodCall();
  calculator_ui.WaitForIncomingMethodCall();
  EXPECT_EQ(10.0, calculator_ui.GetOutput());
}

TEST_F(InterfacePtrTest, Movable) {
  math::CalculatorPtr a;
  math::CalculatorPtr b;
  BindToProxy(new MathCalculatorImpl(), &b);

  EXPECT_TRUE(!a);
  EXPECT_FALSE(!b);

  a = b.Pass();

  EXPECT_FALSE(!a);
  EXPECT_TRUE(!b);
}

TEST_F(InterfacePtrTest, Resettable) {
  math::CalculatorPtr a;

  EXPECT_TRUE(!a);

  MessagePipe pipe;

  // Save this so we can test it later.
  Handle handle = pipe.handle0.get();

  a = MakeProxy<math::Calculator>(pipe.handle0.Pass());

  EXPECT_FALSE(!a);

  a.reset();

  EXPECT_TRUE(!a);
  EXPECT_FALSE(a.internal_state()->router_for_testing());

  // Test that handle was closed.
  EXPECT_EQ(MOJO_RESULT_INVALID_ARGUMENT, CloseRaw(handle));
}

TEST_F(InterfacePtrTest, EncounteredError) {
  math::CalculatorPtr proxy;
  MathCalculatorImpl* server = BindToProxy(new MathCalculatorImpl(), &proxy);

  MathCalculatorUI calculator_ui(proxy.Pass());

  calculator_ui.Add(2.0);
  PumpMessages();
  EXPECT_EQ(2.0, calculator_ui.GetOutput());
  EXPECT_FALSE(calculator_ui.encountered_error());

  calculator_ui.Multiply(5.0);
  EXPECT_FALSE(calculator_ui.encountered_error());

  // Close the server.
  server->internal_router()->CloseMessagePipe();

  // The state change isn't picked up locally yet.
  EXPECT_FALSE(calculator_ui.encountered_error());

  PumpMessages();

  // OK, now we see the error.
  EXPECT_TRUE(calculator_ui.encountered_error());
}

TEST_F(InterfacePtrTest, EncounteredErrorCallback) {
  math::CalculatorPtr proxy;
  MathCalculatorImpl* server = BindToProxy(new MathCalculatorImpl(), &proxy);

  ErrorObserver error_observer;
  proxy.set_error_handler(&error_observer);

  MathCalculatorUI calculator_ui(proxy.Pass());

  calculator_ui.Add(2.0);
  PumpMessages();
  EXPECT_EQ(2.0, calculator_ui.GetOutput());
  EXPECT_FALSE(calculator_ui.encountered_error());

  calculator_ui.Multiply(5.0);
  EXPECT_FALSE(calculator_ui.encountered_error());

  // Close the server.
  server->internal_router()->CloseMessagePipe();

  // The state change isn't picked up locally yet.
  EXPECT_FALSE(calculator_ui.encountered_error());

  PumpMessages();

  // OK, now we see the error.
  EXPECT_TRUE(calculator_ui.encountered_error());

  // We should have also been able to observe the error through the
  // ErrorHandler interface.
  EXPECT_TRUE(error_observer.encountered_error());
}

TEST_F(InterfacePtrTest, NoClientAttribute) {
  // This is a test to ensure the following compiles. The sample::Port interface
  // does not have an explicit Client attribute.
  sample::PortPtr port;
  MessagePipe pipe;
  port.Bind(pipe.handle0.Pass());
}

TEST_F(InterfacePtrTest, DestroyInterfacePtrOnClientMethod) {
  math::CalculatorPtr proxy;
  BindToProxy(new MathCalculatorImpl(), &proxy);

  EXPECT_EQ(0, SelfDestructingMathCalculatorUI::num_instances());

  SelfDestructingMathCalculatorUI* impl =
      new SelfDestructingMathCalculatorUI(proxy.Pass());
  impl->BeginTest(false);

  PumpMessages();

  EXPECT_EQ(0, SelfDestructingMathCalculatorUI::num_instances());
}

TEST_F(InterfacePtrTest, NestedDestroyInterfacePtrOnClientMethod) {
  math::CalculatorPtr proxy;
  BindToProxy(new MathCalculatorImpl(), &proxy);

  EXPECT_EQ(0, SelfDestructingMathCalculatorUI::num_instances());

  SelfDestructingMathCalculatorUI* impl =
      new SelfDestructingMathCalculatorUI(proxy.Pass());
  impl->BeginTest(true);

  PumpMessages();

  EXPECT_EQ(0, SelfDestructingMathCalculatorUI::num_instances());
}

TEST_F(InterfacePtrTest, ReentrantWaitForIncomingMethodCall) {
  sample::ServicePtr proxy;
  ReentrantServiceImpl* impl = BindToProxy(new ReentrantServiceImpl(), &proxy);

  proxy->Frobinate(nullptr, sample::Service::BAZ_OPTIONS_REGULAR, nullptr);
  proxy->Frobinate(nullptr, sample::Service::BAZ_OPTIONS_REGULAR, nullptr);

  PumpMessages();

  EXPECT_EQ(2, impl->max_call_depth());
}

class StrongMathCalculatorImpl : public math::Calculator, public ErrorHandler {
 public:
  StrongMathCalculatorImpl(ScopedMessagePipeHandle handle,
                           bool* error_received,
                           bool* destroyed)
      : error_received_(error_received),
        destroyed_(destroyed),
        binding_(this, handle.Pass()) {
    binding_.set_error_handler(this);
  }
  ~StrongMathCalculatorImpl() override { *destroyed_ = true; }

  // math::Calculator implementation.
  void Clear(const CalcCallback& callback) override { callback.Run(total_); }

  void Add(double value, const CalcCallback& callback) override {
    total_ += value;
    callback.Run(total_);
  }

  void Multiply(double value, const CalcCallback& callback) override {
    total_ *= value;
    callback.Run(total_);
  }

  // ErrorHandler implementation.
  void OnConnectionError() override { *error_received_ = true; }

 private:
  double total_ = 0.0;
  bool* error_received_;
  bool* destroyed_;

  StrongBinding<math::Calculator> binding_;
};

TEST(StrongConnectorTest, Math) {
  Environment env;
  RunLoop loop;

  bool error_received = false;
  bool destroyed = false;
  MessagePipe pipe;
  new StrongMathCalculatorImpl(pipe.handle0.Pass(), &error_received,
                               &destroyed);

  math::CalculatorPtr calc;
  calc.Bind(pipe.handle1.Pass());

  {
    // Suppose this is instantiated in a process that has the other end of the
    // message pipe.
    MathCalculatorUI calculator_ui(calc.Pass());

    calculator_ui.Add(2.0);
    calculator_ui.Multiply(5.0);

    loop.RunUntilIdle();

    EXPECT_EQ(10.0, calculator_ui.GetOutput());
    EXPECT_FALSE(error_received);
    EXPECT_FALSE(destroyed);
  }
  // Destroying calculator_ui should close the pipe and generate an error on the
  // other
  // end which will destroy the instance since it is strongly bound.

  loop.RunUntilIdle();
  EXPECT_TRUE(error_received);
  EXPECT_TRUE(destroyed);
}

class WeakMathCalculatorImpl : public math::Calculator, public ErrorHandler {
 public:
  WeakMathCalculatorImpl(ScopedMessagePipeHandle handle,
                         bool* error_received,
                         bool* destroyed)
      : error_received_(error_received),
        destroyed_(destroyed),
        binding_(this, handle.Pass()) {
    binding_.set_error_handler(this);
  }
  ~WeakMathCalculatorImpl() override { *destroyed_ = true; }

  void Clear(const CalcCallback& callback) override { callback.Run(total_); }

  void Add(double value, const CalcCallback& callback) override {
    total_ += value;
    callback.Run(total_);
  }

  void Multiply(double value, const CalcCallback& callback) override {
    total_ *= value;
    callback.Run(total_);
  }

  // ErrorHandler implementation.
  void OnConnectionError() override { *error_received_ = true; }

 private:
  double total_ = 0.0;
  bool* error_received_;
  bool* destroyed_;

  Binding<math::Calculator> binding_;
};

TEST(WeakConnectorTest, Math) {
  Environment env;
  RunLoop loop;

  bool error_received = false;
  bool destroyed = false;
  MessagePipe pipe;
  WeakMathCalculatorImpl impl(pipe.handle0.Pass(), &error_received, &destroyed);

  math::CalculatorPtr calc;
  calc.Bind(pipe.handle1.Pass());

  {
    // Suppose this is instantiated in a process that has the other end of the
    // message pipe.
    MathCalculatorUI calculator_ui(calc.Pass());

    calculator_ui.Add(2.0);
    calculator_ui.Multiply(5.0);

    loop.RunUntilIdle();

    EXPECT_EQ(10.0, calculator_ui.GetOutput());
    EXPECT_FALSE(error_received);
    EXPECT_FALSE(destroyed);
    // Destroying calculator_ui should close the pipe and generate an error on
    // the other
    // end which will destroy the instance since it is strongly bound.
  }

  loop.RunUntilIdle();
  EXPECT_TRUE(error_received);
  EXPECT_FALSE(destroyed);
}

}  // namespace
}  // namespace test
}  // namespace mojo