#ifndef MIGRAPHX_GUARD_OPERATORS_IF_OP_HPP
#define MIGRAPHX_GUARD_OPERATORS_IF_OP_HPP

#include <array>
#include <migraphx/check_shapes.hpp>
#include <migraphx/argument.hpp>
#include <migraphx/functional.hpp>
#include <migraphx/config.hpp>
#include <migraphx/module.hpp>
#include <cmath>
#include <utility>
#include <set>

namespace migraphx {
inline namespace MIGRAPHX_INLINE_NS {
namespace op {

struct if_op
{
    std::string name() const { return "if"; }

    shape compute_shape(const std::vector<shape>& inputs, std::vector<module_ref> mods) const
    {
        check_shapes{inputs, *this}.standard();
        if(mods.size() != 2)
        {
            MIGRAPHX_THROW("IF: operator should have two submodules.");
        }

        auto out_shapes0 = mods[0]->get_output_shapes();
        auto out_shapes1 = mods[1]->get_output_shapes();
        if(not std::equal(
               out_shapes1.begin(), out_shapes1.end(), out_shapes0.begin(), out_shapes0.end()))
        {
            MIGRAPHX_THROW("IF: output shapes of submodules must be the same.");
        }

        return shape(out_shapes0);
    }

    argument compute(const shape&,
                     const std::vector<argument>& args,
                     const std::vector<module_ref>& mods,
                     const std::function<std::vector<argument>(
                         module_ref&, const std::unordered_map<std::string, argument>&)>& run) const
    {
        auto cond      = args.front().at<bool>();
        module_ref mod = cond ? mods[0] : mods[1];
        std::unordered_map<std::string, argument> params;

        std::set<std::string> pnames;
        for(const auto& smod : mods)
        {
            auto names = smod->get_parameter_names();
            pnames.insert(names.begin(), names.end());
        }

        assert(pnames.size() < args.size());
        std::transform(pnames.begin(),
                       pnames.end(),
                       args.begin() + 1,
                       std::inserter(params, params.end()),
                       [](auto&& name, auto&& arg) { return std::make_pair(name, arg); });

        auto results = run(mod, params);
        return argument{results};
    }
};

} // namespace op
} // namespace MIGRAPHX_INLINE_NS
} // namespace migraphx

#endif
