#include <migraphx/tf/op_parser.hpp>
#include <migraphx/tf/tf_parser.hpp>
#include <migraphx/instruction.hpp>
#include <migraphx/ranges.hpp>
#include <migraphx/make_op.hpp>

namespace migraphx {
inline namespace MIGRAPHX_INLINE_NS {
namespace tf {

struct parse_pad : op_parser<parse_pad>
{
    bool transpose() const { return true; }
    std::vector<op_desc> operators() const { return {{"Pad"}}; }

    instruction_ref parse(const op_desc& /*opd*/,
                          const tf_parser& parser,
                          const tf_parser::node_info& info,
                          std::vector<instruction_ref> args) const
    {
        int ndims = args.front()->get_shape().lens().size();

        // in tf, the paddings are arranged as a 2d shape (ndims, 2),
        // the last dim contains the left padding and right padding respectively
        std::vector<std::pair<int32_t, int32_t>> pad_per_dim(ndims);
        auto tf_padding = args[1]->eval().get<int32_t>().to_vector();
        for(int i = 0; i < 2 * ndims; i += 2)
        {
            pad_per_dim[i / 2].first  = tf_padding[i];
            pad_per_dim[i / 2].second = tf_padding[i + 1];
        }
        parser.reorder_data(pad_per_dim);

        std::vector<int64_t> pads(ndims * 2);
        for(int i = 0; i < ndims; i++)
        {
            pads[i]         = pad_per_dim[i].first;
            pads[i + ndims] = pad_per_dim[i].second;
        }
        return info.add_instruction(make_op("pad", {{"pads", pads}}), args.front());
    }
};

} // namespace tf
} // namespace MIGRAPHX_INLINE_NS
} // namespace migraphx