/* Copyright (c) 2008 - 2021 Advanced Micro Devices, Inc.

 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
 in the Software without restriction, including without limitation the rights
 to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 copies of the Software, and to permit persons to whom the Software is
 furnished to do so, subject to the following conditions:

 The above copyright notice and this permission notice shall be included in
 all copies or substantial portions of the Software.

 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 THE SOFTWARE. */

#ifndef CONTEXT_HPP_
#define CONTEXT_HPP_

#include "top.hpp"
#include "device/device.hpp"
#include "platform/object.hpp"
#include "platform/agent.hpp"

#include <vector>
#include <unordered_map>

namespace amd {

/*! \addtogroup Runtime
 *  @{
 *
 *  \addtogroup Contexts
 *  @{
 */

class GLFunctions;
class DeviceQueue;

class Context : public RuntimeObject {
  std::vector<Device*> devices_;

 public:
  enum DeviceFlagIdx {
    GLDeviceKhrIdx = 0,   //!< GL
    D3D10DeviceKhrIdx,    //!< D3D10
    OfflineDevicesIdx,    //!< Offline devices
    CommandInterceptIdx,  //!< (Deprecated) Command intercept
    D3D11DeviceKhrIdx,    //!< D3D11
    InteropUserSyncIdx,   //!< Interop user sync enabled
    D3D9DeviceKhrIdx,     //!< d3d9 device
    D3D9DeviceEXKhrIdx,   //!< d3d9EX device
    D3D9DeviceVAKhrIdx,   //!< d3d9VA device
    EGLDeviceKhrIdx,      //!< EGL device
    LastDeviceFlagIdx
  };

  enum Flags {
    GLDeviceKhr = 1 << GLDeviceKhrIdx,            //!< GL
    D3D10DeviceKhr = 1 << D3D10DeviceKhrIdx,      //!< D3D10
    OfflineDevices = 1 << OfflineDevicesIdx,      //!< Offline devices
    D3D11DeviceKhr = 1 << D3D11DeviceKhrIdx,      //!< D3D11
    InteropUserSync = 1 << InteropUserSyncIdx,    //!< Interop user sync enabled
    D3D9DeviceKhr = 1 << D3D9DeviceKhrIdx,        //!< d3d9 device
    D3D9DeviceEXKhr = 1 << D3D9DeviceEXKhrIdx,    //!< d3d9EX device
    D3D9DeviceVAKhr = 1 << D3D9DeviceVAKhrIdx,    //!< d3d9VA device
    EGLDeviceKhr = 1 << EGLDeviceKhrIdx,          //!< EGL device
  };

  //! Context info structure
  struct Info {
    uint flags_;                     //!< Context info flags
    void* hDev_[LastDeviceFlagIdx];  //!< Device object reference
    void* hCtx_;                     //!< Context object reference
    size_t propertiesSize_;          //!< Size of the original properties in bytes
  };

  struct DeviceQueueInfo {
    DeviceQueue* defDeviceQueue_;  //!< Default device queue
    uint deviceQueueCnt_;          //!< The number of device queues
    DeviceQueueInfo() : defDeviceQueue_(NULL), deviceQueueCnt_(0) {}
  };

 private:
  // Copying a Context is not allowed
  Context(const Context&);
  Context& operator=(const Context&);

 protected:
  bool terminate() {
    if (Agent::shouldPostContextEvents()) {
      Agent::postContextFree(as_cl(this));
    }
    return true;
  }
  //! Context destructor
  ~Context();

 public:
  /*! \brief Helper function to check the context properties and initialize
   *  context info structure
   *
   *  \return An errcode if invalid, CL_SUCCESS if valid
   */
  static int checkProperties(const cl_context_properties* properties,  //!< Properties
                             Info* info                                //!< Info structure
                             );

  //! Default constructor
  Context(const std::vector<Device*>& devices,  //!< List of all devices
          const Info& info                      //!< Context info structure
          );

  //! Compare two Context instances.
  bool operator==(const Context& rhs) const { return this == &rhs; }
  bool operator!=(const Context& rhs) const { return !(*this == rhs); }

  /*! Creates the context
   *
   *  \return An errcode if runtime fails the context creation,
   *          CL_SUCCESS otherwise
   */
  int create(const intptr_t* properties  //!< Original context properties
             );

  /**
   * Allocate host memory using either a custom device allocator or a generic
   * OS allocator
   *
   * @param size Allocation size, in bytes
   * @param alignment Desired alignment, in bytes
   * @param atomics The buffer should support platform (SVM) atomics
   */
  void* hostAlloc(size_t size, size_t alignment, bool atomics = false) const;

  /**
   * Release host memory
   * @param ptr Pointer allocated using ::hostAlloc. If the pointer has been
   * allocated elsewhere, the behavior is undefined
   */
  void hostFree(void* ptr) const;

  /**
   * Allocate SVM buffer
   *
   * @param size Allocation size, in bytes
   * @param alignment Desired alignment, in bytes
   * @param flags The flags to create a svm space
   * @param curDev The current device
   */
  void* svmAlloc(size_t size, size_t alignment, cl_svm_mem_flags flags = CL_MEM_READ_WRITE,
                 const amd::Device* curDev = nullptr);

  /**
   * Release SVM buffer
   * @param ptr Pointer allocated using ::svmAlloc. If the pointer has been
   * allocated elsewhere, the behavior is undefined
   */
  void svmFree(void* ptr) const;

  //! Return the devices associated with this context.
  const std::vector<Device*>& devices() const { return devices_; }

  //! Return the SVM capable devices associated with this context.
  const std::vector<Device*>& svmDevices() const { return svmAllocDevice_; }

  //! Returns true if the given device is associated with this context.
  bool containsDevice(const Device* device) const;

  //! Returns the context info structure
  const Info& info() const { return info_; }

  void setInfo(Info info) {
    info_ = info;
    return;
  }

  //! Returns a pointer to the original properties
  const cl_context_properties* properties() const { return properties_; }

  //! Returns a pointer to the OpenGL context
  GLFunctions* glenv() const { return glenv_; }

  //! RTTI internal implementation
  virtual ObjectType objectType() const { return ObjectTypeContext; }

  //! Returns context lock for the serialized access to the context
  Monitor& lock() { return ctxLock_; }

  //! Returns TRUE if runtime succesfully added a device queue
  DeviceQueue* defDeviceQueue(const Device& dev) const;

  //! Returns TRUE if runtime succesfully added a device queue
  bool isDevQueuePossible(const Device& dev);

  //! Returns TRUE if runtime succesfully added a device queue
  void addDeviceQueue(const Device& dev,   //!< Device object
                      DeviceQueue* queue,  //!< Device queue
                      bool defDevQueue     //!< Added device queue will be the default queue
                      );

  //! Removes a device queue from the list of queues
  void removeDeviceQueue(const Device& dev,  //!< Device object
                         DeviceQueue* queue  //!< Device queue
                         );

  //! Set the default device queue
  void setDefDeviceQueue(const Device& dev, DeviceQueue* queue)
      { deviceQueues_[&dev].defDeviceQueue_ = queue; };

 private:
  Info info_;                            //!< Context info structure
  cl_context_properties* properties_;    //!< Original properties
  GLFunctions* glenv_;                   //!< OpenGL context
  Device* customHostAllocDevice_;        //!< Device responsible for host allocations
  std::vector<Device*> svmAllocDevice_;  //!< Devices can support SVM allocations
  std::unordered_map<const Device*, DeviceQueueInfo> deviceQueues_;  //!< Device queues mapping
  mutable Monitor ctxLock_;                                          //!< Lock for the context access
};

/*! @}
 *  @}
 */

}  // namespace amd

#endif /*CONTEXT_HPP_*/