/* SPDX-License-Identifier: GPL-2.0-or-later
 * Copyright 2011 Blender Foundation. */

#pragma once

#include "COM_MultiThreadedOperation.h"

namespace blender::compositor {

class MapUVOperation : public MultiThreadedOperation {
 private:
  static constexpr int IMAGE_INPUT_INDEX = 0;
  static constexpr int UV_INPUT_INDEX = 1;
  /**
   * Cached reference to the input_program
   */
  SocketReader *inputUVProgram_;
  SocketReader *input_color_program_;

  int uv_width_;
  int uv_height_;
  int image_width_;
  int image_height_;

  float alpha_;

  std::function<void(float x, float y, float *out)> uv_input_read_fn_;

 public:
  MapUVOperation();

  /**
   * we need a 3x3 differential filter for UV Input and full buffer for the image
   */
  bool determine_depending_area_of_interest(rcti *input,
                                            ReadBufferOperation *read_operation,
                                            rcti *output) override;

  /**
   * The inner loop of this operation.
   */
  void execute_pixel_sampled(float output[4], float x, float y, PixelSampler sampler) override;

  void pixel_transform(const float xy[2], float r_uv[2], float r_deriv[2][2], float &r_alpha);

  void init_data() override;

  /**
   * Initialize the execution
   */
  void init_execution() override;

  /**
   * Deinitialize the execution
   */
  void deinit_execution() override;

  void set_alpha(float alpha)
  {
    alpha_ = alpha;
  }

  void get_area_of_interest(int input_idx, const rcti &output_area, rcti &r_input_area) override;
  void update_memory_buffer_started(MemoryBuffer *output,
                                    const rcti &area,
                                    Span<MemoryBuffer *> inputs) override;
  void update_memory_buffer_partial(MemoryBuffer *output,
                                    const rcti &area,
                                    Span<MemoryBuffer *> inputs) override;

 private:
  bool read_uv(float x, float y, float &r_u, float &r_v, float &r_alpha);
};

}  // namespace blender::compositor