
#include "update_ops_cpp.hpp"
#include "utility.hpp"

void reversible_boolean_gate(const UINT* target_qubit_index_list,
    UINT target_qubit_index_count,
    std::function<ITYPE(ITYPE, ITYPE)> function_ptr, CTYPE* state, ITYPE dim) {
    // matrix dim, mask, buffer
    const ITYPE matrix_dim = 1ULL << target_qubit_index_count;
    const ITYPE* matrix_mask_list = create_matrix_mask_list(
        target_qubit_index_list, target_qubit_index_count);

    // insert index
    const UINT* sorted_insert_index_list = create_sorted_ui_list(
        target_qubit_index_list, target_qubit_index_count);

    // loop variables
    const ITYPE loop_dim = dim >> target_qubit_index_count;

    CTYPE* buffer = (CTYPE*)malloc((size_t)(sizeof(CTYPE) * matrix_dim));
    ITYPE state_index;
    for (state_index = 0; state_index < loop_dim; ++state_index) {
        // create base index
        ITYPE basis_0 = state_index;
        for (UINT cursor = 0; cursor < target_qubit_index_count; cursor++) {
            UINT insert_index = sorted_insert_index_list[cursor];
            basis_0 = insert_zero_to_basis_index(
                basis_0, 1ULL << insert_index, insert_index);
        }

        // compute matrix-vector multiply

        for (ITYPE x = 0; x < matrix_dim; ++x) {
            ITYPE y = function_ptr(x, matrix_dim);
            buffer[y] = state[basis_0 ^ matrix_mask_list[x]];
        }

        // set result
        for (ITYPE y = 0; y < matrix_dim; ++y) {
            state[basis_0 ^ matrix_mask_list[y]] = buffer[y];
        }
    }
    free(buffer);
    free((UINT*)sorted_insert_index_list);
    free((ITYPE*)matrix_mask_list);
}
