/*
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 */

#pragma once

#include "FN_multi_function.hh"

namespace blender::bke {

using fn::CPPType;

struct ConversionFunctions {
  const fn::MultiFunction *multi_function;
  void (*convert_single_to_initialized)(const void *src, void *dst);
  void (*convert_single_to_uninitialized)(const void *src, void *dst);
};

class DataTypeConversions {
 private:
  Map<std::pair<fn::MFDataType, fn::MFDataType>, ConversionFunctions> conversions_;

 public:
  void add(fn::MFDataType from_type,
           fn::MFDataType to_type,
           const fn::MultiFunction &fn,
           void (*convert_single_to_initialized)(const void *src, void *dst),
           void (*convert_single_to_uninitialized)(const void *src, void *dst))
  {
    conversions_.add_new({from_type, to_type},
                         {&fn, convert_single_to_initialized, convert_single_to_uninitialized});
  }

  const ConversionFunctions *get_conversion_functions(fn::MFDataType from, fn::MFDataType to) const
  {
    return conversions_.lookup_ptr({from, to});
  }

  const ConversionFunctions *get_conversion_functions(const CPPType &from, const CPPType &to) const
  {
    return this->get_conversion_functions(fn::MFDataType::ForSingle(from),
                                          fn::MFDataType::ForSingle(to));
  }

  const fn::MultiFunction *get_conversion_multi_function(fn::MFDataType from,
                                                         fn::MFDataType to) const
  {
    const ConversionFunctions *functions = this->get_conversion_functions(from, to);
    return functions ? functions->multi_function : nullptr;
  }

  bool is_convertible(const CPPType &from_type, const CPPType &to_type) const
  {
    return conversions_.contains(
        {fn::MFDataType::ForSingle(from_type), fn::MFDataType::ForSingle(to_type)});
  }

  void convert_to_uninitialized(const CPPType &from_type,
                                const CPPType &to_type,
                                const void *from_value,
                                void *to_value) const;

  void convert_to_initialized_n(fn::GSpan from_span, fn::GMutableSpan to_span) const;

  fn::GVArray try_convert(fn::GVArray varray, const CPPType &to_type) const;

  fn::GVMutableArray try_convert(fn::GVMutableArray varray, const CPPType &to_type) const;
};

const DataTypeConversions &get_implicit_type_conversions();

}  // namespace blender::bke