path: root/src/openvic-simulation/country/CountryInstance.cpp

#include "CountryInstance.hpp"

#include "openvic-simulation/country/CountryDefinition.hpp"
#include "openvic-simulation/history/CountryHistory.hpp"
#include "openvic-simulation/map/MapInstance.hpp"
#include "openvic-simulation/misc/Define.hpp"
#include "openvic-simulation/politics/Ideology.hpp"
#include "openvic-simulation/research/Invention.hpp"
#include "openvic-simulation/research/Technology.hpp"

using namespace OpenVic;

using enum CountryInstance::country_status_t;

static constexpr colour_t ERROR_COLOUR = colour_t::from_integer(0xFF0000);

CountryInstance::CountryInstance(
   CountryDefinition const* new_country_definition,
   decltype(technologies)::keys_t const& technology_keys,
   decltype(inventions)::keys_t const& invention_keys,
   decltype(upper_house)::keys_t const& ideology_keys,
   decltype(government_flag_overrides)::keys_t const& government_type_keys,
   decltype(pop_type_distribution)::keys_t const& pop_type_keys,
   decltype(unlocked_regiment_types)::keys_t const& unlocked_regiment_types_keys,
   decltype(unlocked_ship_types)::keys_t const& unlocked_ship_types_keys
) : /* Main attributes */
   country_definition { new_country_definition },
   colour { ERROR_COLOUR },
   capital { nullptr },
   country_flags {},
   releasable_vassal { true },
   country_status { COUNTRY_STATUS_UNCIVILISED },
   lose_great_power_date {},
   total_score { 0 },
   total_rank { 0 },
   owned_provinces {},
   controlled_provinces {},
   core_provinces {},
   states {},

   /* Production */
   industrial_power { 0 },
   industrial_power_from_states {},
   industrial_power_from_investments {},
   industrial_rank { 0 },
   foreign_investments {},

   /* Budget */
   cash_stockpile { 0 },

   /* Technology */
   technologies { &technology_keys },
   inventions { &invention_keys },
   current_research { nullptr },
   invested_research_points { 0 },
   expected_completion_date {},
   research_point_stockpile { 0 },
   daily_research_points { 0 },
   national_literacy { 0 },
   tech_school { nullptr },

   /* Politics */
   national_value { nullptr },
   government_type { nullptr },
   last_election {},
   ruling_party { nullptr },
   upper_house { &ideology_keys },
   reforms {},
   government_flag_overrides { &government_type_keys },
   flag_government_type { nullptr },
   suppression_points { 0 },
   infamy { 0 },
   plurality { 0 },
   revanchism { 0 },

   /* Population */
   primary_culture { nullptr },
   accepted_cultures {},
   religion { nullptr },
   total_population { 0 },
   national_consciousness { 0 },
   national_militancy { 0 },
   pop_type_distribution { &pop_type_keys },
   national_focus_capacity { 0 },

   /* Trade */

   /* Diplomacy */
   prestige { 0 },
   prestige_rank { 0 },
   diplomatic_points { 0 },

   /* Military */
   military_power { 0 },
   military_power_from_land { 0 },
   military_power_from_sea { 0 },
   military_power_from_leaders { 0 },
   military_rank { 0 },
   generals {},
   admirals {},
   armies {},
   navies {},
   regiment_count { 0 },
   max_supported_regiment_count { 0 },
   mobilisation_potential_regiment_count { 0 },
   mobilisation_max_regiment_count { 0 },
   mobilisation_impact { 0 },
   supply_consumption { 1 },
   ship_count { 0 },
   total_consumed_ship_supply { 0 },
   max_ship_supply { 0 },
   leadership_points { 0 },
   war_exhaustion { 0 },
   mobilised { false },
   disarmed { false },
   unlocked_regiment_types { &unlocked_regiment_types_keys },
   allowed_regiment_cultures { RegimentType::allowed_cultures_t::NO_CULTURES },
   unlocked_ship_types { &unlocked_ship_types_keys } {

   for (RegimentType const& regiment_type : *unlocked_regiment_types.get_keys()) {
      if (regiment_type.is_active()) {
         unlock_unit_type(regiment_type);
      }
   }

   for (ShipType const& ship_type : *unlocked_ship_types.get_keys()) {
      if (ship_type.is_active()) {
         unlock_unit_type(ship_type);
      }
   }
}

std::string_view CountryInstance::get_identifier() const {
   return country_definition->get_identifier();
}

bool CountryInstance::exists() const {
   return !owned_provinces.empty();
}

bool CountryInstance::is_civilised() const {
   return country_status <= COUNTRY_STATUS_CIVILISED;
}

bool CountryInstance::can_colonise() const {
   return country_status <= COUNTRY_STATUS_SECONDARY_POWER;
}

bool CountryInstance::is_great_power() const {
   return country_status == COUNTRY_STATUS_GREAT_POWER;
}

bool CountryInstance::is_secondary_power() const {
   return country_status == COUNTRY_STATUS_SECONDARY_POWER;
}

bool CountryInstance::set_country_flag(std::string_view flag, bool warn) {
   if (flag.empty()) {
      Logger::error("Attempted to set empty country flag for country ", get_identifier());
      return false;
   }
   if (!country_flags.emplace(flag).second && warn) {
      Logger::warning(
         "Attempted to set country flag \"", flag, "\" for country ", get_identifier(), ": already set!"
      );
   }
   return true;
}

bool CountryInstance::clear_country_flag(std::string_view flag, bool warn) {
   if (flag.empty()) {
      Logger::error("Attempted to clear empty country flag from country ", get_identifier());
      return false;
   }
   if (country_flags.erase(flag) == 0 && warn) {
      Logger::warning(
         "Attempted to clear country flag \"", flag, "\" from country ", get_identifier(), ": not set!"
      );
   }
   return true;
}

#define ADD_AND_REMOVE(item) \
   bool CountryInstance::add_##item(std::remove_pointer_t<decltype(item##s)::value_type>& new_item) { \
      if (!item##s.emplace(&new_item).second) { \
         Logger::error( \
            "Attempted to add " #item " \"", new_item.get_identifier(), "\" to country ", get_identifier(), \
            ": already present!" \
         ); \
         return false; \
      } \
      return true; \
   } \
   bool CountryInstance::remove_##item(std::remove_pointer_t<decltype(item##s)::value_type>& item_to_remove) { \
      if (item##s.erase(&item_to_remove) == 0) { \
         Logger::error( \
            "Attempted to remove " #item " \"", item_to_remove.get_identifier(), "\" from country ", get_identifier(), \
            ": not present!" \
         ); \
         return false; \
      } \
      return true; \
   }

ADD_AND_REMOVE(owned_province)
ADD_AND_REMOVE(controlled_province)
ADD_AND_REMOVE(core_province)
ADD_AND_REMOVE(state)
ADD_AND_REMOVE(accepted_culture)

#undef ADD_AND_REMOVE

bool CountryInstance::set_upper_house(Ideology const* ideology, fixed_point_t popularity) {
   if (ideology != nullptr) {
      upper_house[*ideology] = popularity;
      return true;
   } else {
      Logger::error("Trying to set null ideology in upper house of ", get_identifier());
      return false;
   }
}

bool CountryInstance::add_reform(Reform const* new_reform) {
   if (std::find(reforms.begin(), reforms.end(), new_reform) != reforms.end()) {
      Logger::warning(
         "Attempted to add reform \"", new_reform, "\" to country ", get_identifier(), ": already present!"
      );
      return false;
   }
   reforms.push_back(new_reform);
   return true;
}

bool CountryInstance::remove_reform(Reform const* reform_to_remove) {
   auto existing_entry = std::find(reforms.begin(), reforms.end(), reform_to_remove);
   if (existing_entry == reforms.end()) {
      Logger::warning(
         "Attempted to remove reform \"", reform_to_remove, "\" from country ", get_identifier(), ": not present!"
      );
      return false;
   }
   reforms.erase(existing_entry);
   return true;
}

template<UnitType::branch_t Branch>
bool CountryInstance::add_unit_instance_group(UnitInstanceGroup<Branch>& group) {
   if (get_unit_instance_groups<Branch>().emplace(static_cast<UnitInstanceGroupBranched<Branch>*>(&group)).second) {
      return true;
   } else {
      Logger::error(
         "Trying to add already-existing ", Branch == UnitType::branch_t::LAND ? "army" : "navy", " ",
         group.get_name(), " to country ", get_identifier()
      );
      return false;
   }
}

template<UnitType::branch_t Branch>
bool CountryInstance::remove_unit_instance_group(UnitInstanceGroup<Branch>& group) {
   if (get_unit_instance_groups<Branch>().erase(static_cast<UnitInstanceGroupBranched<Branch>*>(&group)) > 0) {
      return true;
   } else {
      Logger::error(
         "Trying to remove non-existent ", Branch == UnitType::branch_t::LAND ? "army" : "navy", " ",
         group.get_name(), " from country ", get_identifier()
      );
      return false;
   }
}

template bool CountryInstance::add_unit_instance_group(UnitInstanceGroup<UnitType::branch_t::LAND>&);
template bool CountryInstance::add_unit_instance_group(UnitInstanceGroup<UnitType::branch_t::NAVAL>&);
template bool CountryInstance::remove_unit_instance_group(UnitInstanceGroup<UnitType::branch_t::LAND>&);
template bool CountryInstance::remove_unit_instance_group(UnitInstanceGroup<UnitType::branch_t::NAVAL>&);

template<UnitType::branch_t Branch>
void CountryInstance::add_leader(LeaderBranched<Branch>&& leader) {
   get_leaders<Branch>().emplace(std::move(leader));
}

template<UnitType::branch_t Branch>
bool CountryInstance::remove_leader(LeaderBranched<Branch> const* leader) {
   plf::colony<LeaderBranched<Branch>>& leaders = get_leaders<Branch>();
   const auto it = leaders.get_iterator(leader);
   if (it != leaders.end()) {
      leaders.erase(it);
      return true;
   }

   Logger::error(
      "Trying to remove non-existent ", Branch == UnitType::branch_t::LAND ? "general" : "admiral", " ",
      leader != nullptr ? leader->get_name() : "NULL", " from country ", get_identifier()
   );
   return false;
}

template void CountryInstance::add_leader(LeaderBranched<UnitType::branch_t::LAND>&&);
template void CountryInstance::add_leader(LeaderBranched<UnitType::branch_t::NAVAL>&&);
template bool CountryInstance::remove_leader(LeaderBranched<UnitType::branch_t::LAND> const*);
template bool CountryInstance::remove_leader(LeaderBranched<UnitType::branch_t::NAVAL> const*);

template<UnitType::branch_t Branch>
void CountryInstance::unlock_unit_type(UnitTypeBranched<Branch> const& unit_type) {
   IndexedMap<UnitTypeBranched<Branch>, bool>& unlocked_unit_types = get_unlocked_unit_types<Branch>();

   decltype(unlocked_regiment_types)::value_ref_t unlock_value = unlocked_unit_types[unit_type];

   if (unlock_value) {
      Logger::warning(
         "Attempted to unlock already-unlocked unit type \"", unit_type.get_identifier(),
         "\" for country ", get_identifier()
      );
      return;
   }

   unlock_value = true;

   if constexpr (Branch == UnitType::branch_t::LAND) {
      allowed_regiment_cultures = RegimentType::allowed_cultures_get_most_permissive(
         allowed_regiment_cultures, unit_type.get_allowed_cultures()
      );
   }
}

template void CountryInstance::unlock_unit_type(UnitTypeBranched<UnitType::branch_t::LAND> const&);
template void CountryInstance::unlock_unit_type(UnitTypeBranched<UnitType::branch_t::NAVAL> const&);

bool CountryInstance::is_primary_culture(Culture const& culture) const {
   return &culture == primary_culture;
}

bool CountryInstance::is_accepted_culture(Culture const& culture) const {
   return accepted_cultures.contains(&culture);
}

bool CountryInstance::is_primary_or_accepted_culture(Culture const& culture) const {
   return is_primary_culture(culture) || is_accepted_culture(culture);
}

void CountryInstance::apply_foreign_investments(
   fixed_point_map_t<CountryDefinition const*> const& investments, CountryInstanceManager const& country_instance_manager
) {
   for (auto const& [country, money_invested] : investments) {
      foreign_investments[&country_instance_manager.get_country_instance_from_definition(*country)] = money_invested;
   }
}

bool CountryInstance::apply_history_to_country(
   CountryHistoryEntry const& entry, MapInstance& map_instance, CountryInstanceManager const& country_instance_manager
) {
   constexpr auto set_optional = []<typename T>(T& target, std::optional<T> const& source) {
      if (source) {
         target = *source;
      }
   };

   bool ret = true;

   set_optional(primary_culture, entry.get_primary_culture());
   for (Culture const* culture : entry.get_accepted_cultures()) {
      ret &= add_accepted_culture(*culture);
   }
   set_optional(religion, entry.get_religion());
   set_optional(ruling_party, entry.get_ruling_party());
   set_optional(last_election, entry.get_last_election());
   ret &= upper_house.copy(entry.get_upper_house());
   if (entry.get_capital()) {
      capital = &map_instance.get_province_instance_from_definition(**entry.get_capital());
   }
   set_optional(government_type, entry.get_government_type());
   set_optional(plurality, entry.get_plurality());
   set_optional(national_value, entry.get_national_value());
   if (entry.is_civilised()) {
      country_status = *entry.is_civilised() ? COUNTRY_STATUS_CIVILISED : COUNTRY_STATUS_UNCIVILISED;
   }
   set_optional(prestige, entry.get_prestige());
   for (Reform const* reform : entry.get_reforms()) {
      ret &= add_reform(reform);
   }
   set_optional(tech_school, entry.get_tech_school());
   constexpr auto set_bool_map_to_indexed_map =
      []<typename T>(IndexedMap<T, bool>& target, ordered_map<T const*, bool> source) {
         for (auto const& [key, value] : source) {
            target[*key] = value;
         }
      };
   set_bool_map_to_indexed_map(technologies, entry.get_technologies());
   set_bool_map_to_indexed_map(inventions, entry.get_inventions());
   apply_foreign_investments(entry.get_foreign_investment(), country_instance_manager);

   // These need to be applied to pops
   // entry.get_consciousness();
   // entry.get_nonstate_consciousness();
   // entry.get_literacy();
   // entry.get_nonstate_culture_literacy();

   set_optional(releasable_vassal, entry.is_releasable_vassal());
   // entry.get_colonial_points();
   for (std::string const& flag : entry.get_country_flags()) {
      ret &= set_country_flag(flag, true);
   }
   for (std::string const& flag : entry.get_global_flags()) {
      // TODO - set global flag
   }
   government_flag_overrides.write_non_empty_values(entry.get_government_flag_overrides());
   for (Decision const* decision : entry.get_decisions()) {
      // TODO - take decision
   }

   return ret;
}

void CountryInstance::_update_production(DefineManager const& define_manager) {
   // Calculate industrial power from states and foreign investments
   industrial_power = 0;
   industrial_power_from_states.clear();
   industrial_power_from_investments.clear();

   for (State const* state : states) {
      const fixed_point_t state_industrial_power = state->get_industrial_power();
      if (state_industrial_power != 0) {
         industrial_power += state_industrial_power;
         industrial_power_from_states.emplace_back(state, state_industrial_power);
      }
   }

   for (auto const& [country, money_invested] : foreign_investments) {
      if (country->exists()) {
         const fixed_point_t investment_industrial_power =
            money_invested * define_manager.get_country_investment_industrial_score_factor() / 100;

         if (investment_industrial_power != 0) {
            industrial_power += investment_industrial_power;
            industrial_power_from_investments.emplace_back(country, investment_industrial_power);
         }
      }
   }

   std::sort(
      industrial_power_from_states.begin(), industrial_power_from_states.end(),
      [](auto const& a, auto const& b) -> bool { return a.second > b.second; }
   );
   std::sort(
      industrial_power_from_investments.begin(), industrial_power_from_investments.end(),
      [](auto const& a, auto const& b) -> bool { return a.second > b.second; }
   );
}

void CountryInstance::_update_budget() {

}

void CountryInstance::_update_technology() {

}

void CountryInstance::_update_politics() {

}

void CountryInstance::_update_population() {
   total_population = 0;
   national_literacy = 0;
   national_consciousness = 0;
   national_militancy = 0;
   pop_type_distribution.clear();

   for (State const* state : states) {
      total_population += state->get_total_population();

      // TODO - change casting if Pop::pop_size_t changes type
      const fixed_point_t state_population = fixed_point_t::parse(state->get_total_population());
      national_literacy += state->get_average_literacy() * state_population;
      national_consciousness += state->get_average_consciousness() * state_population;
      national_militancy += state->get_average_militancy() * state_population;

      pop_type_distribution += state->get_pop_type_distribution();
   }

   if (total_population > 0) {
      national_literacy /= total_population;
      national_consciousness /= total_population;
      national_militancy /= total_population;
   }

   // TODO - update national focus capacity
}

void CountryInstance::_update_trade() {
   // TODO - update total amount of each good exported and imported
}

void CountryInstance::_update_diplomacy() {
   // TODO - add prestige from modifiers
   // TODO - update diplomatic points and colonial power
}

void CountryInstance::_update_military(DefineManager const& define_manager, UnitTypeManager const& unit_type_manager) {
   regiment_count = 0;

   for (ArmyInstance const* army : armies) {
      regiment_count += army->get_unit_count();
   }

   ship_count = 0;
   total_consumed_ship_supply = 0;

   for (NavyInstance const* navy : navies) {
      ship_count += navy->get_unit_count();
      total_consumed_ship_supply += navy->get_total_consumed_supply();
   }

   // Calculate military power from land, sea, and leaders

   size_t deployed_non_mobilised_regiments = 0;
   for (ArmyInstance const* army : armies) {
      for (RegimentInstance const* regiment : army->get_units()) {
         if (!regiment->is_mobilised()) {
            deployed_non_mobilised_regiments++;
         }
      }
   }

   max_supported_regiment_count = 0;
   for (State const* state : states) {
      max_supported_regiment_count += state->get_max_supported_regiments();
   }

   // TODO - apply country/tech modifiers to supply consumption
   supply_consumption = 1;

   const size_t regular_army_size = std::min(4 * deployed_non_mobilised_regiments, max_supported_regiment_count);

   fixed_point_t sum_of_regiment_type_stats = 0;
   for (RegimentType const& regiment_type : unit_type_manager.get_regiment_types()) {
      // TODO - apply country/tech modifiers to regiment stats
      sum_of_regiment_type_stats += (
         regiment_type.get_attack() + regiment_type.get_defence() /*+ land_attack_modifier + land_defense_modifier*/
      ) * regiment_type.get_discipline();
   }

   military_power_from_land = supply_consumption * fixed_point_t::parse(regular_army_size) * sum_of_regiment_type_stats
      / fixed_point_t::parse(7 * (1 + unit_type_manager.get_regiment_type_count()));

   if (disarmed) {
      military_power_from_land *= define_manager.get_disarmed_penalty();
   }

   military_power_from_sea = 0;
   for (NavyInstance const* navy : navies) {
      for (ShipInstance const* ship : navy->get_units()) {
         ShipType const& ship_type = ship->get_unit_type();

         if (ship_type.is_capital()) {

            // TODO - include gun power and hull modifiers + naval attack and defense modifiers

            military_power_from_sea += (ship_type.get_gun_power() /*+ naval_attack_modifier*/)
               * (ship_type.get_hull() /* + naval_defense_modifier*/);
         }
      }
   }
   military_power_from_sea /= 250;

   military_power_from_leaders = fixed_point_t::parse(
      std::min(generals.size() + admirals.size(), deployed_non_mobilised_regiments)
   );

   military_power = military_power_from_land + military_power_from_sea + military_power_from_leaders;

   // Mobilisation calculations
   mobilisation_impact = 0; // TODO - apply ruling party's war policy

   mobilisation_max_regiment_count =
      ((fixed_point_t::_1() + mobilisation_impact) * fixed_point_t::parse(regiment_count)).to_int64_t();

   mobilisation_potential_regiment_count = 0; // TODO - calculate max regiments from poor citizens
   if (mobilisation_potential_regiment_count > mobilisation_max_regiment_count) {
      mobilisation_potential_regiment_count = mobilisation_max_regiment_count;
   }

   // TODO - update max_ship_supply, leadership_points, war_exhaustion
}

void CountryInstance::update_gamestate(DefineManager const& define_manager, UnitTypeManager const& unit_type_manager) {
   // Order of updates might need to be changed/functions split up to account for dependencies
   _update_production(define_manager);
   _update_budget();
   _update_technology();
   _update_politics();
   _update_population();
   _update_trade();
   _update_diplomacy();
   _update_military(define_manager, unit_type_manager);

   total_score = prestige + industrial_power + military_power;

   if (country_definition != nullptr) {
      const CountryDefinition::government_colour_map_t::const_iterator it =
         country_definition->get_alternative_colours().find(government_type);

      if (it != country_definition->get_alternative_colours().end()) {
         colour = it->second;
      } else {
         colour = country_definition->get_colour();
      }
   } else {
      colour = ERROR_COLOUR;
   }

   if (government_type != nullptr) {
      flag_government_type = government_flag_overrides[*government_type];

      if (flag_government_type == nullptr) {
         flag_government_type = government_type;
      }
   } else {
      flag_government_type = nullptr;
   }
}

void CountryInstance::tick() {

}

void CountryInstanceManager::update_rankings(Date today, DefineManager const& define_manager) {
   total_ranking.clear();

   for (CountryInstance& country : country_instances.get_items()) {
      if (country.exists()) {
         total_ranking.push_back(&country);
      }
   }

   prestige_ranking = total_ranking;
   industrial_power_ranking = total_ranking;
   military_power_ranking = total_ranking;

   std::sort(
      total_ranking.begin(), total_ranking.end(),
      [](CountryInstance const* a, CountryInstance const* b) -> bool {
         const bool a_civilised = a->is_civilised();
         const bool b_civilised = b->is_civilised();
         return a_civilised != b_civilised ? a_civilised : a->get_total_score() > b->get_total_score();
      }
   );
   std::sort(
      prestige_ranking.begin(), prestige_ranking.end(),
      [](CountryInstance const* a, CountryInstance const* b) -> bool {
         return a->get_prestige() > b->get_prestige();
      }
   );
   std::sort(
      industrial_power_ranking.begin(), industrial_power_ranking.end(),
      [](CountryInstance const* a, CountryInstance const* b) -> bool {
         return a->get_industrial_power() > b->get_industrial_power();
      }
   );
   std::sort(
      military_power_ranking.begin(), military_power_ranking.end(),
      [](CountryInstance const* a, CountryInstance const* b) -> bool {
         return a->get_military_power() > b->get_military_power();
      }
   );

   for (size_t index = 0; index < total_ranking.size(); ++index) {
      const size_t rank = index + 1;
      total_ranking[index]->total_rank = rank;
      prestige_ranking[index]->prestige_rank = rank;
      industrial_power_ranking[index]->industrial_rank = rank;
      military_power_ranking[index]->military_rank = rank;
   }

   const size_t max_great_power_rank = define_manager.get_great_power_rank();
   const size_t max_secondary_power_rank = define_manager.get_secondary_power_rank();
   const Timespan lose_great_power_grace_days = define_manager.get_lose_great_power_grace_days();

   // Demote great powers who have been below the max great power rank for longer than the demotion grace period and
   // remove them from the list. We don't just demote them all and clear the list as when rebuilding we'd need to look
   // ahead for countries below the max great power rank but still within the demotion grace period.
   for (CountryInstance* great_power : great_powers) {
      if (great_power->get_total_rank() > max_great_power_rank && great_power->get_lose_great_power_date() < today) {
         great_power->country_status = COUNTRY_STATUS_CIVILISED;
      }
   }
   std::erase_if(great_powers, [](CountryInstance const* country) -> bool {
      return country->get_country_status() != COUNTRY_STATUS_GREAT_POWER;
   });

   // Demote all secondary powers and clear the list. We will rebuilt the whole list from scratch, so there's no need to
   // keep countries which are still above the max secondary power rank (they might become great powers instead anyway).
   for (CountryInstance* secondary_power : secondary_powers) {
      secondary_power->country_status = COUNTRY_STATUS_CIVILISED;
   }
   secondary_powers.clear();

   // Calculate the maximum number of countries eligible for great or secondary power status. This accounts for the
   // possibility of the max secondary power rank being higher than the max great power rank or both being zero, just
   // in case someone wants to experiment with only having secondary powers when some great power slots are filled by
   // countries in the demotion grace period, or having no great or secondary powers at all.
   const size_t max_power_index = std::clamp(max_secondary_power_rank, max_great_power_rank, total_ranking.size());

   for (size_t index = 0; index < max_power_index; index++) {
      CountryInstance* country = total_ranking[index];

      if (!country->is_civilised()) {
         // All further countries are civilised and so ineligible for great or secondary power status.
         break;
      }

      if (country->is_great_power()) {
         // The country already has great power status and is in the great powers list.
         continue;
      }

      if (great_powers.size() < max_great_power_rank && country->get_total_rank() <= max_great_power_rank) {
         // The country is eligible for great power status and there are still slots available,
         // so it is promoted and added to the list.
         country->country_status = COUNTRY_STATUS_GREAT_POWER;
         great_powers.push_back(country);
      } else if (country->get_total_rank() <= max_secondary_power_rank) {
         // The country is eligible for secondary power status and so is promoted and added to the list.
         country->country_status = COUNTRY_STATUS_SECONDARY_POWER;
         secondary_powers.push_back(country);
      }
   }

   // Sort the great powers list by total rank, as pre-existing great powers may have changed rank order and new great
   // powers will have beeen added to the end of the list regardless of rank.
   std::sort(great_powers.begin(), great_powers.end(), [](CountryInstance const* a, CountryInstance const* b) -> bool {
      return a->get_total_rank() < b->get_total_rank();
   });

   // Update the lose great power date for all great powers which are above the max great power rank.
   const Date new_lose_great_power_date = today + lose_great_power_grace_days;
   for (CountryInstance* great_power : great_powers) {
      if (great_power->get_total_rank() <= max_great_power_rank) {
         great_power->lose_great_power_date = new_lose_great_power_date;
      }
   }
}

CountryInstance& CountryInstanceManager::get_country_instance_from_definition(CountryDefinition const& country) {
   return country_instances.get_items()[country.get_index()];
}

CountryInstance const& CountryInstanceManager::get_country_instance_from_definition(CountryDefinition const& country) const {
   return country_instances.get_items()[country.get_index()];
}

bool CountryInstanceManager::generate_country_instances(
   CountryDefinitionManager const& country_definition_manager,
   decltype(CountryInstance::technologies)::keys_t const& technology_keys,
   decltype(CountryInstance::inventions)::keys_t const& invention_keys,
   decltype(CountryInstance::upper_house)::keys_t const& ideology_keys,
   decltype(CountryInstance::government_flag_overrides)::keys_t const& government_type_keys,
   decltype(CountryInstance::pop_type_distribution)::keys_t const& pop_type_keys,
   decltype(CountryInstance::unlocked_regiment_types)::keys_t const& unlocked_regiment_types_keys,
   decltype(CountryInstance::unlocked_ship_types)::keys_t const& unlocked_ship_types_keys
) {
   reserve_more(country_instances, country_definition_manager.get_country_definition_count());

   for (CountryDefinition const& country_definition : country_definition_manager.get_country_definitions()) {
      country_instances.add_item({
         &country_definition, technology_keys, invention_keys, ideology_keys, government_type_keys, pop_type_keys,
         unlocked_regiment_types_keys, unlocked_ship_types_keys
      });
   }

   return true;
}

bool CountryInstanceManager::apply_history_to_countries(
   CountryHistoryManager const& history_manager, Date date, UnitInstanceManager& unit_instance_manager,
   MapInstance& map_instance
) {
   bool ret = true;

   for (CountryInstance& country_instance : country_instances.get_items()) {
      if (!country_instance.get_country_definition()->is_dynamic_tag()) {
         CountryHistoryMap const* history_map =
            history_manager.get_country_history(country_instance.get_country_definition());

         if (history_map != nullptr) {
            CountryHistoryEntry const* oob_history_entry = nullptr;

            for (auto const& [entry_date, entry] : history_map->get_entries()) {
               if (entry_date <= date) {
                  ret &= country_instance.apply_history_to_country(*entry, map_instance, *this);

                  if (entry->get_inital_oob()) {
                     oob_history_entry = entry.get();
                  }
               } else {
                  // All foreign investments are applied regardless of the bookmark's date
                  country_instance.apply_foreign_investments(entry->get_foreign_investment(), *this);
               }
            }

            if (oob_history_entry != nullptr) {
               ret &= unit_instance_manager.generate_deployment(
                  map_instance, country_instance, *oob_history_entry->get_inital_oob()
               );
            }
         } else {
            Logger::error("Country ", country_instance.get_identifier(), " has no history!");
            ret = false;
         }
      }
   }

   return ret;
}

void CountryInstanceManager::update_gamestate(
   Date today, DefineManager const& define_manager, UnitTypeManager const& unit_type_manager
) {
   for (CountryInstance& country : country_instances.get_items()) {
      country.update_gamestate(define_manager, unit_type_manager);
   }

   update_rankings(today, define_manager);
}

void CountryInstanceManager::tick() {
   for (CountryInstance& country : country_instances.get_items()) {
      country.tick();
   }
}