/*
 * Copyright 2016 The Chromium OS Authors. All rights reserved.
 * Use of this source code is governed by a BSD-style license that can be
 * found in the LICENSE file.
 */

#ifndef CAMERA_HAL_ADAPTER_CAMERA_DEVICE_ADAPTER_H_
#define CAMERA_HAL_ADAPTER_CAMERA_DEVICE_ADAPTER_H_

#include <deque>
#include <map>
#include <memory>
#include <string>
#include <unordered_map>
#include <utility>
#include <vector>

#include <hardware/camera3.h>

#include <base/containers/flat_map.h>
#include <base/files/scoped_file.h>
#include <base/synchronization/lock.h>
#include <base/threading/thread.h>
#include <base/timer/timer.h>
#include <camera/camera_metadata.h>
#include <mojo/public/cpp/bindings/binding.h>
#include <system/camera_metadata.h>

#include "common/utils/common_types.h"
#include "common/utils/cros_camera_mojo_utils.h"
#include "cros-camera/camera_buffer_manager.h"
#include "cros-camera/camera_metrics.h"
#include "hal_adapter/camera_metadata_inspector.h"
#include "hal_adapter/frame_number_mapper.h"
#include "hal_adapter/scoped_yuv_buffer_handle.h"
#include "hal_adapter/zsl_helper.h"
#include "mojo/camera3.mojom.h"

namespace cros {

class Camera3DeviceOpsDelegate;

class Camera3CallbackOpsDelegate;

// Flattened capture request
class Camera3CaptureRequest : public camera3_capture_request_t {
 public:
  explicit Camera3CaptureRequest(const camera3_capture_request_t& req);

  ~Camera3CaptureRequest() = default;

 private:
  android::CameraMetadata settings_;

  camera3_stream_buffer_t input_buffer_;

  std::vector<camera3_stream_buffer_t> output_stream_buffers_;
};

class CameraDeviceAdapter : public camera3_callback_ops_t {
 public:
  explicit CameraDeviceAdapter(camera3_device_t* camera_device,
                               const camera_metadata_t* static_info,
                               base::Callback<void()> close_callback);

  ~CameraDeviceAdapter();

  using HasReprocessEffectVendorTagCallback =
      base::Callback<bool(const camera_metadata_t&)>;
  using ReprocessEffectCallback =
      base::Callback<int32_t(const camera_metadata_t&,
                             ScopedYUVBufferHandle*,
                             uint32_t,
                             uint32_t,
                             android::CameraMetadata*,
                             ScopedYUVBufferHandle*)>;
  using AllocatedBuffers =
      base::flat_map<uint64_t, std::vector<mojom::Camera3StreamBufferPtr>>;
  // Starts the camera device adapter.  This method must be called before all
  // the other methods are called.
  bool Start(HasReprocessEffectVendorTagCallback
                 has_reprocess_effect_vendor_tag_callback,
             ReprocessEffectCallback reprocess_effect_callback);

  // Bind() is called by CameraHalAdapter in OpenDevice() on the mojo IPC
  // handler thread in |module_delegate_|.
  void Bind(mojom::Camera3DeviceOpsRequest device_ops_request);

  // Callback interface for Camera3DeviceOpsDelegate.
  // These methods are callbacks for |device_ops_delegate_| and are executed on
  // the mojo IPC handler thread in |device_ops_delegate_|.

  int32_t Initialize(mojom::Camera3CallbackOpsPtr callback_ops);

  int32_t ConfigureStreams(
      mojom::Camera3StreamConfigurationPtr config,
      mojom::Camera3StreamConfigurationPtr* updated_config);

  mojom::CameraMetadataPtr ConstructDefaultRequestSettings(
      mojom::Camera3RequestTemplate type);

  int32_t ProcessCaptureRequest(mojom::Camera3CaptureRequestPtr request);

  void Dump(mojo::ScopedHandle fd);

  int32_t Flush();

  int32_t RegisterBuffer(uint64_t buffer_id,
                         mojom::Camera3DeviceOps::BufferType type,
                         std::vector<mojo::ScopedHandle> fds,
                         uint32_t drm_format,
                         mojom::HalPixelFormat hal_pixel_format,
                         uint32_t width,
                         uint32_t height,
                         const std::vector<uint32_t>& strides,
                         const std::vector<uint32_t>& offsets);

  int32_t Close();

  int32_t ConfigureStreamsAndGetAllocatedBuffers(
      mojom::Camera3StreamConfigurationPtr config,
      mojom::Camera3StreamConfigurationPtr* updated_config,
      AllocatedBuffers* allocated_buffers);

 private:
  // Implementation of camera3_callback_ops_t.
  static void ProcessCaptureResult(const camera3_callback_ops_t* ops,
                                   const camera3_capture_result_t* result);

  static void Notify(const camera3_callback_ops_t* ops,
                     const camera3_notify_msg_t* msg);

  // Allocates buffers for given |streams|. Returns true and the allocated
  // buffers will be put in |allocated_buffers| if the allocation succeeds.
  // Otherwise, false is returned.
  bool AllocateBuffersForStreams(
      const std::vector<mojom::Camera3StreamPtr>& streams,
      AllocatedBuffers* allocated_buffers);

  // Frees all allocated stream buffers that are allocated locally.
  void FreeAllocatedStreamBuffers();

  int32_t RegisterBufferLocked(uint64_t buffer_id,
                               mojom::Camera3DeviceOps::BufferType type,
                               std::vector<mojo::ScopedHandle> fds,
                               uint32_t drm_format,
                               mojom::HalPixelFormat hal_pixel_format,
                               uint32_t width,
                               uint32_t height,
                               const std::vector<uint32_t>& strides,
                               const std::vector<uint32_t>& offsets);
  int32_t RegisterBufferLocked(mojom::CameraBufferHandlePtr buffer);

  // NOTE: All the fds in |result| (e.g. fences and buffer handles) will be
  // closed after the function returns.  The caller needs to dup a fd in
  // |result| if the fd will be accessed after calling ProcessCaptureResult.
  mojom::Camera3CaptureResultPtr PrepareCaptureResult(
      const camera3_capture_result_t* result);

  void PreprocessNotifyMsg(const camera3_notify_msg_t* msg,
                           std::vector<camera3_notify_msg_t>* msgs);

  mojom::Camera3NotifyMsgPtr PrepareNotifyMsg(const camera3_notify_msg_t* msg);

  // Caller must hold |buffer_handles_lock_|.
  void RemoveBufferLocked(const camera3_stream_buffer_t& buffer);

  // Waits until |release_fence| is signaled and then deletes |buffer|.
  void RemoveBufferOnFenceSyncThread(
      base::ScopedFD release_fence,
      std::unique_ptr<camera_buffer_handle_t> buffer);

  void ReprocessEffectsOnReprocessEffectThread(
      std::unique_ptr<Camera3CaptureRequest> req);

  void ProcessReprocessRequestOnDeviceOpsThread(
      std::unique_ptr<Camera3CaptureRequest> req,
      base::Callback<void(int32_t)> callback);

  void NotifyAddedFrameError(
      camera3_capture_request_t req,
      std::vector<camera3_stream_buffer_t> output_buffers);

  void NotifyAddedFrameErrorOnNotifyErrorThread(
      camera3_capture_request_t req,
      std::vector<camera3_stream_buffer_t> output_buffers);

  void ResetDeviceOpsDelegateOnThread();
  void ResetCallbackOpsDelegateOnThread();

  void MonitorTimeout(const std::string& name);

  // The thread that all the camera3 device ops operate on.
  base::Thread camera_device_ops_thread_;

  // The thread that all the Mojo communications of camera3 callback ops operate
  // on.
  base::Thread camera_callback_ops_thread_;

  // A thread to asynchronously wait for release fences and destroy
  // corresponding buffer handles.
  base::Thread fence_sync_thread_;

  // A thread to apply reprocessing effects
  base::Thread reprocess_effect_thread_;

  // A thread to notify errors in added requests.
  base::Thread notify_error_thread_;

  // A thread that handles timeouts of request/response monitors.
  base::Thread monitor_thread_;

  // The delegate that handles the Camera3DeviceOps mojo IPC.
  std::unique_ptr<Camera3DeviceOpsDelegate> device_ops_delegate_;

  // The delegate that handles the Camera3CallbackOps mojo IPC.
  std::unique_ptr<Camera3CallbackOpsDelegate> callback_ops_delegate_;
  // Lock to protect |callback_ops_delegate_| as it is accessed on multiple
  // threads.
  base::Lock callback_ops_delegate_lock_;

  // The callback to run when the device is closed.
  base::Callback<void()> close_callback_;

  // Set when the camera device is closed.  No more calls to the device APIs may
  // be made once |device_closed_| is set.
  bool device_closed_;

  // The real camera device.
  camera3_device_t* camera_device_;

  // The non-owning read-only view of the static camera characteristics of this
  // device.
  const camera_metadata_t* static_info_;

  // A helper class that includes various functions for the mechanisms of ZSL.
  ZslHelper zsl_helper_;

  // The stream configured for ZSL requests.
  camera3_stream_t* zsl_stream_;

  // A mapping from Andoird HAL for all the configured streams.
  internal::ScopedStreams streams_;

  // A mutex to guard |streams_|.
  base::Lock streams_lock_;

  // A mapping from the locally created buffer handle to the handle ID of the
  // imported buffer.  We need to return the correct handle ID in
  // ProcessCaptureResult so the camera client, which allocated the imported
  // buffer, can restore the buffer handle in the capture result before passing
  // up to the upper layer.
  std::unordered_map<uint64_t, std::unique_ptr<camera_buffer_handle_t>>
      buffer_handles_;

  // A mapping that stores all buffer handles that are allocated when streams
  // are configured locally. When the session is over, all of these handles
  // should be freed.
  std::map<uint64_t, buffer_handle_t> allocated_stream_buffers_;

  // A queue of reprocessing buffers.
  std::deque<ScopedYUVBufferHandle> reprocess_handles_;

  // A queue of original input buffer handles replaced by reprocessing ones.
  std::deque<uint64_t> input_buffer_handle_ids_;

  // A mapping from the frame number to the result metadata generated by
  // reprocessing effects
  std::unordered_map<uint32_t, android::CameraMetadata>
      reprocess_result_metadata_;

  // A pending reprocessing request task for HAL to run.
  base::OnceClosure process_reprocess_request_callback_;
  base::Lock process_reprocess_request_callback_lock_;

  // A mutex to guard |buffer_handles_|.
  base::Lock buffer_handles_lock_;

  // A mutex to guard |reprocess_handles_| and |input_buffer_handle_ids_|.
  base::Lock reprocess_handles_lock_;

  // A mutex to guard |reprocess_result_metadata_|.
  base::Lock reprocess_result_metadata_lock_;

  // The callback to check reprocessing effect vendor tags.
  HasReprocessEffectVendorTagCallback has_reprocess_effect_vendor_tag_callback_;

  // The callback to handle reprocessing effect.
  ReprocessEffectCallback reprocess_effect_callback_;

  // The metadata inspector to dump capture requests / results in realtime
  // for debugging if enabled.
  std::unique_ptr<CameraMetadataInspector> camera_metadata_inspector_;

  // Metrics for camera service.
  std::unique_ptr<CameraMetrics> camera_metrics_;

  // Utility for mapping framework and HAL frame numbers.
  FrameNumberMapper frame_number_mapper_;

  // ANDROID_PARTIAL_RESULT_COUNT from static metadata.
  int32_t partial_result_count_;

  // Monitors for capture requests and capture results. If there is no capture
  // requests/responses for a while the monitors will output a log to indicate
  // this situation.
  base::OneShotTimer capture_request_monitor_;
  base::OneShotTimer capture_result_monitor_;

  DISALLOW_IMPLICIT_CONSTRUCTORS(CameraDeviceAdapter);
};

}  // namespace cros

#endif  // CAMERA_HAL_ADAPTER_CAMERA_DEVICE_ADAPTER_H_