#include <clippy/project_list.hpp>
#include <filesystem>
#include <utils/lock_file.hpp>

#include <fstream>
#include <mutex>
#include <random>
#include <chrono>

Config ProjectList::GetNewConfig(
    const std::filesystem::path& config_directory) {
  std::lock_guard guard(lock_file_);

  LoadWithouLock();

  std::mt19937 rnd(std::chrono::system_clock::now().time_since_epoch().count());

  auto RandomSymbol = [&rnd]() {
    int n = rnd() % (26 + 26 + 10);
    if (n < 26) {
      return 'a' + n;
    } else if (n < 26 + 26) {
      return 'A' + n - 26;
    } else {
      return '0' + n - 26 - 26;
    }
  };

  auto GenerateFilename = [&rnd, &RandomSymbol]() {
    std::string filename;
    for (size_t i = 0; i < 6; ++i) {
      filename += RandomSymbol();
    }

    return filename;
  };

  auto filename = GenerateFilename();
  while (true) {
    bool exist_config = false;
    for (auto& project : projects_) {
      if (filename == project.configuration_file.filename()) {
        exist_config = true;
        break;
      }
    }
    if (!exist_config) {
      break;
    }

    filename = GenerateFilename();
  }

  auto path_to_config = config_directory / filename;

  std::ofstream out(path_, std::ios::ate);
  out << std::filesystem::current_path() << " " << path_to_config << std::endl;
  out.close();

  projects_.emplace_back(std::filesystem::current_path(), path_to_config);

  return {path_to_config};
}

void ProjectList::Load() {
  std::lock_guard guard(lock_file_);

  LoadWithouLock();
}

void ProjectList::LoadWithouLock() {
  std::ifstream in(path_);

  Project current;

  while (in >> current.root_project >> current.configuration_file) {
    projects_.push_back(current);
  }
}

std::optional<Project> ProjectList::GetCurrentProject() {
  auto current_path = std::filesystem::current_path();

  std::optional<Project> result;
  auto UpdateResult = [&result](Project p) {
    if (!result.has_value()) {
      result = p;
    } else {
      result = std::max(p, result.value());
    }
  };

  for (auto& project : projects_) {
    auto prefix_current_path = current_path;

    if (project.root_project == "/") {
      UpdateResult(project);
      continue;
    }

    while (prefix_current_path != "/") {
      if (prefix_current_path == project.root_project) {
        UpdateResult(project);
      }
      prefix_current_path = prefix_current_path.parent_path();
    }
  }

  return result;
}