text: //  Copyright (c) 2019 Jonas Ellert
  //
  //  Permission is hereby granted, free of charge, to any person obtaining a copy
  //  of this software and associated documentation files (the "Software"), to
  //  deal in the Software without restriction, including without limitation the
  //  rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
  //  sell copies of the Software, and to permit persons to whom the Software is
  //  furnished to do so, subject to the following conditions:
  //
  //  The above copyright notice and this permission notice shall be included in
  //  all copies or substantial portions of the Software.
  //
  //  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  //  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  //  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  //  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  //  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  //  FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
  //  IN THE SOFTWARE.
  
  #pragma once
  
  #include <cmath>
  #include <executable/generator/alphabet.hpp>
  #include <util/common.hpp>
  
  static void ror_internal(uint8_t* result,
                           const uint64_t length,
                           const uint64_t repetitions,
                           const uint64_t char_idx) {
  
    if (length < repetitions) {
      for (uint64_t i = 0; i < repetitions; ++i) {
        result[i] = gen_alphabet[char_idx];
      }
      return;
    }
  
    uint64_t len_per_rep = length / repetitions;
    result[0] = gen_alphabet[char_idx];
    ror_internal(&(result[1]), len_per_rep - 1, repetitions, char_idx + 1);
  
    for (uint64_t i = len_per_rep; i < length; ++i) {
      result[i] = result[i - len_per_rep];
    }
  }
  
  [[maybe_unused]] static std::vector<uint8_t>
  gen_run_of_runs(const uint64_t length, const uint64_t repetitions) {
  
    std::vector<uint8_t> result(length);
    ror_internal(result.data(), length, repetitions, 0);
  
    return result;
  }