//============================================================================//
//                                                                            //
//                       artichoke programming language                       //
//                                                                            //
//      Copyright (C) 2025 Erick Saul Guzman Ramos, whoami.artichoke.dev      //
//                                                                            //
//                                                                            //
//  This program is free software: you can redistribute it and/or modify      //
//  it under the terms of the GNU Affero General Public License as published  //
//  by the Free Software Foundation, either version 3 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 Affero General Public License for more details.                       //
//                                                                            //
//  You should have received a copy of the GNU Affero General Public License  //
//  along with this program.  If not, see <https://www.gnu.org/licenses/>.    //
//                                                                            //
//============================================================================//

#pragma once

#include <random>
#include <ranges>

#include <artichoke/Coroutine/Generator.hpp>

template <std::ranges::range R1, std::ranges::range R2>
requires(
  std::is_convertible_v<std::ranges::range_value_t<R1>, std::string_view> and
  std::is_same_v<std::ranges::range_value_t<R1>, std::ranges::range_value_t<R2>>
)
arti::lang::Generator<std::ranges::range_value_t<R1>>
InterleaveRanges(R1 &&r1, R2 &&r2) {
  auto it1 = std::ranges::begin(r1);
  auto end1 = std::ranges::end(r1);

  auto it2 = std::ranges::begin(r2);
  auto end2 = std::ranges::end(r2);

  while (it1 != end1 && it2 != end2) {
    yield *it1;
    ++it1;
    yield *it2;
    ++it2;
  }
}

static arti::lang::Generator<std::string_view>
WhitespaceGenerator(uint32_t maxLen = 5) {
  constexpr std::array<char, 3> spaceChars{ ' ', '\t', '\n' };

  std::string str;
  std::random_device device;
  std::mt19937 engine(device());
  std::uniform_int_distribution<uint32_t> dist(1, maxLen);
  std::uniform_int_distribution<uint32_t> distChars(0, 2);

  str.reserve(maxLen);

  while (true) {
    str.resize(0);

    auto sz = dist(engine);

    for (uint32_t i = 0; i < sz; ++i) {
      str += spaceChars[distChars(engine)];
    }

    yield str;
  }
}

template <std::ranges::range R>
requires(std::is_same_v<std::ranges::range_value_t<R>, std::string_view>)
static std::string SourceFromTokens(R &&tokens) {
  return InterleaveRanges(tokens, WhitespaceGenerator(10)) | std::views::join |
         std::ranges::to<std::string>();
}