// =================================================================================================
// This file is part of the CLBlast project. The project is licensed under Apache Version 2.0. This
// project loosely follows the Google C++ styleguide and uses a tab-size of two spaces and a max-
// width of 100 characters per line.
//
// Author(s):
//   Cedric Nugteren <www.cedricnugteren.nl>
//
// This file uses the auto-tuner to tune the invert OpenCL kernels.
//
// =================================================================================================

#include <string>
#include <vector>

#include "utilities/utilities.hpp"
#include "tuning/tuning.hpp"

namespace clblast {
// =================================================================================================

// Settings for this kernel (default command-line arguments)
TunerDefaults InvertGetTunerDefaults(const int) {
  auto settings = TunerDefaults();
  settings.options = {kArgN, kArgM, kArgK};
  settings.default_n = 128; // dimension of input matrix 'n'
  settings.default_m = 64; // block size
  settings.default_k = 16; // current size
  return settings;
}

// Settings for this kernel (general)
template <typename T>
TunerSettings InvertGetTunerSettings(const int, const Arguments<T> &args) {
  auto settings = TunerSettings();

  // Identification of the kernel
  settings.kernel_family = "invert";
  settings.kernel_name = "TripleMatMul16Part1Lower";
  settings.sources =
"#define ROUTINE_INVERT"
#include "../src/kernels/level3/invert_diagonal_blocks_part1.opencl"
#include "../src/kernels/level3/invert_diagonal_blocks_part2.opencl"
  ;

  // Buffer sizes
  settings.size_a = args.n * args.n + args.a_offset;
  settings.size_b = Ceil(args.n, args.m) * args.m; // Ceil(n, block_size) * block_size

  // Inputs and outputs IDs (X:0, Y:1, A:2, B:3, C:4, temp:5)
  settings.inputs = {2, 3};
  settings.outputs = {3};

  // Sets the base thread configuration
  const auto num_pages = CeilDiv(args.n, args.k * 2); // CeilDiv(n, current_size*2)
  settings.global_size = {args.k / 4, num_pages * (args.k / 16) * 4};
  settings.global_size_ref = settings.global_size;
  settings.local_size = {1, 1};
  settings.local_size_ref = {4, 4};

  // Transforms the thread configuration based on the parameters
  settings.mul_local = {{"TMMWGSX", "TMMWGSY"}};
  settings.div_global = {{}};

  // Sets the tuning parameters and their possible values
  // TODO: Make these actually tunable, apart from LOCALPAD
  settings.parameters = {
    {"INTERNAL_BLOCK_SIZE", {16}},
    {"LOCALPAD", {0, 1}},
    {"TMMWGSX", {4}},
    {"TMMWGSY", {4}},
  };

  // Describes how to compute the performance metrics
  settings.metric_amount = 1 * GetBytes(args.precision);
  settings.performance_unit = "N/A";

  return settings;
}

// Tests for valid arguments
template <typename T>
void InvertTestValidArguments(const int, const Arguments<T> &args) {
  if (!(args.k == 16)) {
    throw std::runtime_error("'TripleMatMul16Part1Lower' requires 'k' to be 16");
  }
}
std::vector<Constraint> InvertSetConstraints(const int) { return {}; }
template <typename T>
LocalMemSizeInfo InvertComputeLocalMemSize(const int) {
  return {
      [] (std::vector<size_t> v) -> size_t {
          return GetBytes(PrecisionValue<T>()) * (16 + v[0]) * 16;
      },
      {"LOCALPAD"}
  };
}

// Sets the kernel's arguments
template <typename T>
void InvertSetArguments(const int, Kernel &kernel, const Arguments<T> &args, std::vector<Buffer<T>>& buffers) {
  const auto num_pages = CeilDiv(args.n, args.k * 2); // CeilDiv(n, current_size*2)
  kernel.SetArgument(0, static_cast<int>(args.n)); // n
  kernel.SetArgument(1, buffers[2]()); // 2 == A matrix
  kernel.SetArgument(2, 0); // a_offset
  kernel.SetArgument(3, static_cast<int>(args.n)); // a_ld
  kernel.SetArgument(4, buffers[3]()); // 3 == B matrix
  kernel.SetArgument(5, static_cast<int>(args.k)); // current_size
  kernel.SetArgument(6, static_cast<int>(num_pages)); // num_pages
  kernel.SetArgument(7, static_cast<int>(args.m)); // block_size
}

// =================================================================================================
} // namespace clblast