// Copyright 2023 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef SERVICES_DEVICE_GENERIC_SENSOR_VIRTUAL_PLATFORM_SENSOR_PROVIDER_H_
#define SERVICES_DEVICE_GENERIC_SENSOR_VIRTUAL_PLATFORM_SENSOR_PROVIDER_H_

#include "base/containers/flat_map.h"
#include "base/memory/weak_ptr.h"
#include "services/device/generic_sensor/platform_sensor_provider.h"
#include "services/device/public/mojom/sensor_provider.mojom-forward.h"

namespace device {

// OS-agnostic PlatformSensorProvider implementation used in (web) tests. Used
// together with SensorProviderImpl in order to override one or more sensor
// types. Calls to GetSensor() will, upon success, always create
// VirtualPlatformSensor instances.
class VirtualPlatformSensorProvider : public PlatformSensorProvider {
 public:
  VirtualPlatformSensorProvider();
  ~VirtualPlatformSensorProvider() override;

  base::WeakPtr<PlatformSensorProvider> AsWeakPtr() override;

  // Starts causing GetSensor() calls with |type| to return
  // VirtualPlatformSensor instances with the properties specified in
  // |metadata|.
  //
  // Returns false if the given |type| is already being overridden (in which
  // case RemoveSensorOverride() must be called first).
  bool AddSensorOverride(mojom::SensorType type,
                         mojom::VirtualSensorMetadataPtr metadata);

  // Stops overriding sensors of type |type|, that is, GetSensor() calls with
  // |type| will no longer a VirtualPlatformSensor instance. Existing instances
  // will behave as if a hardware sensor had been removed (i.e. possibly notify
  // clients of an error).
  //
  // Does nothing if |type| is not being overridden.
  void RemoveSensorOverride(mojom::SensorType type);

  bool IsOverridingSensor(mojom::SensorType type) const;

  // Adds a new reading to the VirtualPlatformSensor instance associated with
  // |type|.
  //
  // If a VirtualPlatformSensor for |type| has not been created yet, the
  // reading is stashed and passed on to the VirtualPlatformSensor instance
  // once it is created. Multiple calls will override the stashed value.
  //
  // Note: The new reading still goes through
  // PlatformSensor::UpdateSharedBufferAndNotifyClients(), so it may end up not
  // being stored (for example, if a threshold check fails).
  void AddReading(mojom::SensorType type, const SensorReading&);

 private:
  struct TypeMetadata;

  // PlatformSensorProvider overrides.
  void CreateSensorInternal(mojom::SensorType type,
                            CreateSensorCallback callback) override;

  base::flat_map<mojom::SensorType, std::unique_ptr<TypeMetadata>>
      type_metadata_;

  base::WeakPtrFactory<VirtualPlatformSensorProvider> weak_factory_{this};
};

}  // namespace device

#endif  // SERVICES_DEVICE_GENERIC_SENSOR_VIRTUAL_PLATFORM_SENSOR_PROVIDER_H_