advdata.c

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/***********************************************************************
 Freeciv - Copyright (C) 2002 - The Freeciv Project
   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, 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 General Public License for more details.
***********************************************************************/
 
#ifdef HAVE_CONFIG_H
#include <fc_config.h>
#endif
 
/* utility */
#include "log.h"
#include "mem.h"
 
/* common */
#include "actions.h"
#include "ai.h"
#include "city.h"
#include "effects.h"
#include "game.h"
#include "government.h"
#include "map.h"
#include "movement.h"
#include "research.h"
#include "unit.h"
#include "unitlist.h"
 
/* common/aicore */
#include "aisupport.h"
#include "path_finding.h"
#include "pf_tools.h"
 
/* server */
#include "cityturn.h"
#include "diplhand.h"
#include "maphand.h"
#include "plrhand.h"
#include "srv_log.h"
#include "unittools.h"
 
/* server/advisors */
#include "advbuilding.h"
#include "advcity.h"
#include "advtools.h"
#include "autosettlers.h"
 
/* ai */
#include "handicaps.h"
 
#include "advdata.h"
 
static void adv_dipl_new(const struct player *plr1,
                         const struct player *plr2);
static void adv_dipl_free(const struct player *plr1,
                          const struct player *plr2);
static struct adv_dipl *adv_dipl_get(const struct player *plr1,
                                     const struct player *plr2);
 
/**********************************************************************/
static void adv_data_city_impr_calc(struct player *pplayer,
                                    struct adv_data *adv)
{
  int count[ADV_IMPR_LAST];
 
  memset(count, 0, sizeof(count));
 
  improvement_iterate(pimprove) {
    struct universal source = {
      .kind = VUT_IMPROVEMENT,
      .value = {.building = pimprove}
    };
 
    adv->impr_calc[improvement_index(pimprove)] = ADV_IMPR_ESTIMATE;
 
    /* Find largest extension */
    effect_list_iterate(get_req_source_effects(&source), peffect) {
      switch (peffect->type) {
#if 0
      /* TODO */
      case EFT_FORCE_CONTENT:
      case EFT_FORCE_CONTENT_PCT:
      case EFT_MAKE_CONTENT:
      case EFT_MAKE_CONTENT_MIL:
      case EFT_MAKE_CONTENT_MIL_PER:
      case EFT_MAKE_CONTENT_PCT:
      case EFT_MAKE_HAPPY:
#endif
      case EFT_CAPITAL_CITY:
      case EFT_POLLU_POP_PCT:
      case EFT_POLLU_POP_PCT_2:
      case EFT_POLLU_PROD_PCT:
      case EFT_OUTPUT_BONUS:
      case EFT_OUTPUT_BONUS_2:
      case EFT_OUTPUT_WASTE_PCT:
      case EFT_UPKEEP_FREE:
        requirement_vector_iterate(&peffect->reqs, preq) {
          if (VUT_IMPROVEMENT == preq->source.kind
              && preq->source.value.building == pimprove) {
            if (adv->impr_calc[improvement_index(pimprove)] != ADV_IMPR_CALCULATE_FULL) {
              adv->impr_calc[improvement_index(pimprove)] = ADV_IMPR_CALCULATE;
            }
            if (preq->range > adv->impr_range[improvement_index(pimprove)]) {
              adv->impr_range[improvement_index(pimprove)] = preq->range;
            }
          }
        } requirement_vector_iterate_end;
        break;
      case EFT_OUTPUT_ADD_TILE:
      case EFT_OUTPUT_PER_TILE:
      case EFT_OUTPUT_INC_TILE:
        requirement_vector_iterate(&peffect->reqs, preq) {
          if (VUT_IMPROVEMENT == preq->source.kind
              && preq->source.value.building == pimprove) {
            adv->impr_calc[improvement_index(pimprove)] = ADV_IMPR_CALCULATE_FULL;
            if (preq->range > adv->impr_range[improvement_index(pimprove)]) {
              adv->impr_range[improvement_index(pimprove)] = preq->range;
            }
          }
        } requirement_vector_iterate_end;
      break;
      default:
      /* Nothing! */
      break;
      }
    } effect_list_iterate_end;
  } improvement_iterate_end;
}
 
/**********************************************************************/
static bool player_has_really_useful_tech_parasite(struct player* pplayer)
{
  struct research *presearch, *aresearch;
  int players_needed = get_player_bonus(pplayer, EFT_TECH_PARASITE);
 
  if (players_needed == 0) {
    return FALSE;
  }
 
  presearch = research_get(pplayer);
  advance_index_iterate(A_FIRST, tech) {
    int players_having;
 
    if (!research_invention_gettable(presearch, tech,
                                     game.info.tech_parasite_allow_holes)
        || TECH_KNOWN == research_invention_state(presearch, tech)) {
      continue;
    }
 
    players_having = 0;
 
    players_iterate_alive(aplayer) {
      if (aplayer == pplayer) {
        continue;
      }
 
      aresearch = research_get(aplayer);
      if (TECH_KNOWN == research_invention_state(aresearch, tech)
          || aresearch->researching == tech) {
        players_having++;
        if (players_having >= players_needed) {
          return TRUE;
        }
      }
    } players_iterate_alive_end;
  } advance_index_iterate_end;
  return FALSE;
}
 
/**********************************************************************/
void adv_data_analyze_rulesets(struct player *pplayer)
{
  struct adv_data *adv = pplayer->server.adv;
 
  fc_assert_ret(adv != NULL);
 
  adv_data_city_impr_calc(pplayer, adv);
}
 
/**********************************************************************/
static void count_my_units(struct player *pplayer)
{
  struct adv_data *adv = adv_data_get(pplayer, NULL);
 
  memset(&adv->stats.units, 0, sizeof(adv->stats.units));
 
  unit_list_iterate(pplayer->units, punit) {
    struct unit_class *pclass = unit_class_get(punit);
 
    adv->stats.units.byclass[uclass_index(pclass)]++;
 
    if (unit_has_type_flag(punit, UTYF_COAST_STRICT)) {
      adv->stats.units.coast_strict++;
    }
    if (utype_can_do_action(unit_type_get(punit), ACTION_SUICIDE_ATTACK)) {
      adv->stats.units.suicide_attackers++;
    }
    if (unit_can_do_action(punit, ACTION_PARADROP)
        || unit_can_do_action(punit, ACTION_PARADROP_CONQUER)
        || unit_can_do_action(punit, ACTION_PARADROP_FRIGHTEN)
        || unit_can_do_action(punit, ACTION_PARADROP_FRIGHTEN_CONQUER)
        || unit_can_do_action(punit, ACTION_PARADROP_ENTER)
        || unit_can_do_action(punit, ACTION_PARADROP_ENTER_CONQUER)) {
      adv->stats.units.paratroopers++;
    }
    if (utype_can_do_action(punit->utype, ACTION_AIRLIFT)) {
      adv->stats.units.airliftable++;
    }
    if (can_upgrade_unittype(pplayer, unit_type_get(punit)) >= 0) {
      adv->stats.units.upgradeable++;
    }
  } unit_list_iterate_end;
}
 
/**********************************************************************/
bool is_adv_data_phase_open(struct player *pplayer)
{
  struct adv_data *adv = pplayer->server.adv;
 
  return adv->phase_is_initialized;
}
 
/**********************************************************************/
bool adv_data_phase_init(struct player *pplayer, bool is_new_phase)
{
  struct adv_data *adv = pplayer->server.adv;
  bool danger_of_nukes;
  action_id nuke_actions[MAX_NUM_ACTIONS];
 
  {
    int i = 0;
 
    /* Conventional nukes */
    action_list_add_all_by_result(nuke_actions, &i, ACTRES_NUKE);
    action_list_add_all_by_result(nuke_actions, &i, ACTRES_NUKE_UNITS);
    /* TODO: worry about spy nuking too? */
    action_list_end(nuke_actions, i);
  }
 
  fc_assert_ret_val(adv != NULL, FALSE);
 
  if (adv->phase_is_initialized) {
    return FALSE;
  }
  adv->phase_is_initialized = TRUE;
 
  TIMING_LOG(AIT_AIDATA, TIMER_START);
 
  danger_of_nukes = FALSE;
 
  /*** Threats ***/
 
  adv->num_continents    = wld.map.num_continents;
  adv->num_oceans        = wld.map.num_oceans;
  adv->threats.continent = fc_calloc(adv->num_continents + 1, sizeof(bool));
  adv->threats.invasions = FALSE;
  adv->threats.nuclear   = 0; /* none */
  adv->threats.ocean     = fc_calloc(adv->num_oceans + 1, sizeof(bool));
  adv->threats.igwall    = FALSE;
 
  players_iterate(aplayer) {
    if (!adv_is_player_dangerous(pplayer, aplayer)) {
      continue;
    }
 
    /* The idea is that if there aren't any hostile cities on
     * our continent, the danger of land attacks is not big
     * enough to warrant city walls. Concentrate instead on 
     * coastal fortresses and hunting down enemy transports. */
    city_list_iterate(aplayer->cities, acity) {
      Continent_id continent = tile_continent(acity->tile);
      if (continent >= 0) {
        adv->threats.continent[continent] = TRUE;
      }
    } city_list_iterate_end;
 
    unit_list_iterate(aplayer->units, punit) {
      const struct unit_class *pclass = unit_class_get(punit);
 
      if (unit_type_get(punit)->adv.igwall) {
        adv->threats.igwall = TRUE;
      }
 
      if (pclass->adv.sea_move != MOVE_NONE) {
        /* If the enemy has not started sailing yet, or we have total
         * control over the seas, don't worry, keep attacking. */
        if (unit_can_take_over(punit)) {
          /* Enemy represents a cross-continental threat! */
          adv->threats.invasions = TRUE;
        } else if (get_transporter_capacity(punit) > 0) {
          unit_type_iterate(cargotype) {
            if (can_unit_type_transport(unit_type_get(punit),
                                        cargotype->uclass)
                && utype_can_take_over(cargotype)) {
              /* Enemy can transport some threatening units! */
              adv->threats.invasions = TRUE;
              break;
            }
          } unit_type_iterate_end;
        }
 
        /* The idea is that while our enemies don't have any offensive
         * seaborne units, we don't have to worry. Go on the offensive! */
        if (unit_type_get(punit)->attack_strength > 1) {
          if (is_ocean_tile(unit_tile(punit))) {
            Continent_id continent = tile_continent(unit_tile(punit));
 
            adv->threats.ocean[-continent] = TRUE;
          } else {
            adjc_iterate(&(wld.map), unit_tile(punit), tile2) {
              if (is_ocean_tile(tile2)) {
                Continent_id continent = tile_continent(tile2);
 
                adv->threats.ocean[-continent] = TRUE;
              }
            } adjc_iterate_end;
          }
        }
        continue;
      }
 
      /* If our enemy builds missiles, worry about missile defense. */
      if (utype_can_do_action(unit_type_get(punit), ACTION_SUICIDE_ATTACK)
          && unit_type_get(punit)->attack_strength > 1) {
        adv->threats.suicide_attack = TRUE;
      }
 
      /* If they build nukes, worry a lot. */
      action_array_iterate(nuke_actions, act_id) {
        if (unit_can_do_action(punit, act_id)) {
          danger_of_nukes = TRUE;
        }
      } action_array_iterate_end;
    } unit_list_iterate_end;
 
    /* Check for nuke capability */
    action_array_iterate(nuke_actions, act_id) {
      int i;
      int nuke_units = num_role_units(action_id_get_role(act_id));
 
      for (i = 0; i < nuke_units; i++) {
        struct unit_type *nuke =
            get_role_unit(action_id_get_role(act_id), i);
 
        if (can_player_build_unit_direct(aplayer, nuke)) {
          adv->threats.nuclear = 1;
        }
      }
    } action_array_iterate_end;
  } players_iterate_end;
 
  /* Increase from fear to terror if opponent actually has nukes */
  if (danger_of_nukes) {
    adv->threats.nuclear++; /* sum of both fears */
  }
 
  /*** Exploration ***/
 
  adv->explore.land_done = TRUE;
  adv->explore.sea_done = TRUE;
  adv->explore.continent = fc_calloc(adv->num_continents + 1, sizeof(bool));
  adv->explore.ocean = fc_calloc(adv->num_oceans + 1, sizeof(bool));
 
  whole_map_iterate(&(wld.map), ptile) {
    Continent_id continent = tile_continent(ptile);
 
    if (is_ocean_tile(ptile)) {
      if (adv->explore.sea_done && has_handicap(pplayer, H_TARGETS) 
          && !map_is_known(ptile, pplayer)) {
        /* We're not done there. */
        adv->explore.sea_done = FALSE;
        adv->explore.ocean[-continent] = TRUE;
      }
      /* skip rest, which is land only */
      continue;
    }
    if (adv->explore.continent[tile_continent(ptile)]) {
      /* we don't need more explaining, we got the point */
      continue;
    }
    if (hut_on_tile(ptile) 
        && (!has_handicap(pplayer, H_HUTS)
             || map_is_known(ptile, pplayer))) {
      adv->explore.land_done = FALSE;
      adv->explore.continent[continent] = TRUE;
      continue;
    }
    if (has_handicap(pplayer, H_TARGETS) && !map_is_known(ptile, pplayer)) {
      /* this AI must explore */
      adv->explore.land_done = FALSE;
      adv->explore.continent[continent] = TRUE;
    }
  } whole_map_iterate_end;
 
  /*** Statistics ***/
 
  adv->stats.cities = fc_calloc(adv->num_continents + 1, sizeof(int));
  adv->stats.ocean_cities = fc_calloc(adv->num_oceans + 1, sizeof(int));
  adv->stats.average_production = 0;
  city_list_iterate(pplayer->cities, pcity) {
    Continent_id continent = tile_continent(pcity->tile);
 
    if (continent >= 0) {
      adv->stats.cities[continent]++;
    } else {
      adv->stats.ocean_cities[-continent]++;
    }
    adv->stats.average_production += pcity->surplus[O_SHIELD];
  } city_list_iterate_end;
  adv->stats.average_production /= MAX(1, city_list_size(pplayer->cities));
 
  /*** Diplomacy ***/
 
  players_iterate(aplayer) {
    struct adv_dipl *dip = adv_dipl_get(pplayer, aplayer);
 
    dip->allied_with_enemy = FALSE;
    players_iterate(check_pl) {
      if (pplayers_allied(aplayer, check_pl)
          && player_diplstate_get(pplayer, check_pl)->type == DS_WAR) {
        dip->allied_with_enemy = TRUE;
      }
    } players_iterate_end;
  } players_iterate_end;
 
  adv->dipl.spacerace_leader = player_leading_spacerace();
 
  adv->dipl.production_leader = NULL;
  players_iterate(aplayer) {
    if (adv->dipl.production_leader == NULL
        || adv->dipl.production_leader->score.mfg < aplayer->score.mfg) {
      adv->dipl.production_leader = aplayer;
    }
  } players_iterate_end;
 
  adv->dipl.tech_leader = NULL;
  players_iterate(aplayer) {
    if (adv->dipl.tech_leader == NULL
        || adv->dipl.tech_leader->score.techs < aplayer->score.techs) {
      adv->dipl.tech_leader = aplayer;
    }
  } players_iterate_end;
 
  /*** Priorities ***/
 
  /* NEVER set these to zero! Weight values are usually multiplied by 
   * these values, so be careful with them. They are used in city 
   * and government calculations, and food and shields should be 
   * slightly bigger because we only look at surpluses there. They
   * are all WAGs. */
  adv->food_priority = FOOD_WEIGHTING;
  adv->shield_priority = SHIELD_WEIGHTING;
  if (adv_wants_science(pplayer)) {
    adv->luxury_priority = 1;
    adv->science_priority = TRADE_WEIGHTING * 1.2;
  } else {
    adv->luxury_priority = TRADE_WEIGHTING;
    adv->science_priority = 1;
  }
  adv->gold_priority = TRADE_WEIGHTING;
  adv->happy_priority = 1;
  adv->unhappy_priority = TRADE_WEIGHTING; /* danger */
  adv->angry_priority = TRADE_WEIGHTING * 3; /* grave danger */
  adv->pollution_priority = POLLUTION_WEIGHTING;
  adv->infra_priority = INFRA_WEIGHTING;
 
  /* Research want */
  if (is_future_tech(research_get(pplayer)->researching)
      || player_has_really_useful_tech_parasite(pplayer)) {
    adv->wants_science = FALSE;
  } else {
    adv->wants_science = TRUE;
  }
  
  /* max num cities
   * The idea behind this code is that novice players don't understand that
   * expansion is critical and find it very annoying.
   * With the following code AI players will try to be only a bit better 
   * than the best human players. This should lead to more exciting games
   * for the beginners.
   */
  if (has_handicap(pplayer, H_EXPANSION)) {
    bool found_human = FALSE;
    adv->max_num_cities = 3;
    players_iterate_alive(aplayer) {
      if (aplayer == pplayer || is_ai(aplayer)) {
        continue;
      }
      adv->max_num_cities = MAX(adv->max_num_cities,
                                city_list_size(aplayer->cities) + 3);
      found_human = TRUE;
    } players_iterate_alive_end;
    if (!found_human) {
      adv->max_num_cities = MAP_INDEX_SIZE;
    }
  } else {
    adv->max_num_cities = MAP_INDEX_SIZE;
  }
 
  count_my_units(pplayer);
 
  TIMING_LOG(AIT_AIDATA, TIMER_STOP);
 
  /* Government */
  TIMING_LOG(AIT_GOVERNMENT, TIMER_START);
  adv_best_government(pplayer);
  TIMING_LOG(AIT_GOVERNMENT, TIMER_STOP);
 
  return TRUE;
}
 
/**********************************************************************/
void adv_data_phase_done(struct player *pplayer)
{
  struct adv_data *adv = pplayer->server.adv;
 
  fc_assert_ret(adv != NULL);
 
  if (!adv->phase_is_initialized) {
    return;
  }
 
  free(adv->explore.ocean);
  adv->explore.ocean = NULL;
 
  free(adv->explore.continent);
  adv->explore.continent = NULL;
 
  free(adv->threats.continent);
  adv->threats.continent = NULL;
 
  free(adv->threats.ocean);
  adv->threats.ocean = NULL;
 
  free(adv->stats.cities);
  adv->stats.cities = NULL;
 
  free(adv->stats.ocean_cities);
  adv->stats.ocean_cities = NULL;
 
  adv->num_continents = 0;
  adv->num_oceans     = 0;
 
  adv->phase_is_initialized = FALSE;
}
 
/**********************************************************************/
struct adv_data *adv_data_get(struct player *pplayer, bool *caller_closes)
{
  struct adv_data *adv = pplayer->server.adv;
 
  fc_assert_ret_val(adv != NULL, NULL);
 
  /* It's certainly indication of bug causing problems
     if this adv_data_get() gets called between adv_data_phase_done() and
     adv_data_phase_init(), since we may end up calling those
     functions if number of known continents has changed.
 
     Consider following case:
       Correct call order would be:
       a) adv_data_phase_init()
       b)   adv_data_get() -> adv_data_phase_done()
       c)   adv_data_get() -> adv_data_phase_init()
       d) adv_data_phase_done()
       e) do something
       f) adv_data_phase_init()
 
       In (e) data phase would be closed and data would be
       correctly initialized at (f), which is probably beginning
       next turn.
 
       Buggy version where adv_data_get() (b&c) gets called after (d):
       a) adv_data_phase_init()
       d) adv_data_phase_done()
       b)   adv_data_get() -> adv_data_phase_done()
       c)   adv_data_get() -> adv_data_phase_init()
       e) do something
       f) adv_data_phase_init()
 
       Now in (e) data phase would be open. When adv_data_phase_init()
       then finally gets called and it really should recreate data
       to match situation of new turn, it detects that data phase
       is already initialized and does nothing.
 
       So, this assertion is here for a reason!
 
       Code below tries to fix the situation best it can if such a bug is
       encountered. Since we are probably going to trust that to be enough
       instead of making intrusive fixes for actual bug in stable branch,
       do not assert for non-debug builds of stable versions. */
#if defined(FREECIV_DEBUG) || defined(IS_DEVEL_VERSION)
  fc_assert(caller_closes != NULL || adv->phase_is_initialized);
#endif
 
  if (caller_closes != NULL) {
    *caller_closes = FALSE;
  }
 
  if (adv->num_continents != wld.map.num_continents
      || adv->num_oceans != wld.map.num_oceans) {
    /* we discovered more continents, recalculate! */
 
    if (adv->phase_is_initialized) {
      /* Only call these in this order if inside data phase.
         This is blanket "fix" for all cases where adv_data_get() is called
         at illegal time. This at least minimize bad effects of such calls. */
      adv_data_phase_done(pplayer);
      adv_data_phase_init(pplayer, FALSE);
    } else {
      /* Call them in "wrong" order so we return recalculated data to caller,
         but leave data phase closed.
         This is blanket "fix" for all cases where adv_data_get() is called
         at illegal time. This at least minimize bad effects of such calls.
 
         Arguably this is not buggy at all but works just as designed in
         case of being called in alternate movement mode for players
         other than currently moving one (for diplomacy between the two,
         for example) */
      log_debug("%s advisor data phase closed when adv_data_get() called",
                player_name(pplayer));
      adv_data_phase_init(pplayer, FALSE);
      if (caller_closes != NULL) {
        *caller_closes = TRUE;
      } else {
        adv_data_phase_done(pplayer);
      }
    }
  } else {
    if (!adv->phase_is_initialized && caller_closes != NULL) {
      adv_data_phase_init(pplayer, FALSE);
      *caller_closes = TRUE;
    }
  }
 
  return adv;
}
 
/**********************************************************************/
void adv_data_init(struct player *pplayer)
{
  struct adv_data *adv;
 
  if (pplayer->server.adv == NULL) {
    pplayer->server.adv = fc_calloc(1, sizeof(*pplayer->server.adv));
  }
  adv = pplayer->server.adv;
 
  adv->government_want = NULL;
 
  adv->dipl.adv_dipl_slots = fc_calloc(player_slot_count(),
                                       sizeof(*adv->dipl.adv_dipl_slots));
  player_slots_iterate(pslot) {
    struct adv_dipl **dip_slot =
      adv->dipl.adv_dipl_slots + player_slot_index(pslot);
    *dip_slot = NULL;
  } player_slots_iterate_end;
 
  players_iterate(aplayer) {
    adv_dipl_new(pplayer, aplayer);
    if (aplayer != pplayer) {
      adv_dipl_new(aplayer, pplayer);
    }
  } players_iterate_end;
 
  adv_data_default(pplayer);
}
 
/**********************************************************************/
void adv_data_default(struct player *pplayer)
{
  struct adv_data *adv = pplayer->server.adv;
 
  fc_assert_ret(adv != NULL);
 
  adv->govt_reeval = 0;
  adv->government_want = fc_realloc(adv->government_want,
                                   (government_count() + 1)
                                    * sizeof(*adv->government_want));
  memset(adv->government_want, 0,
         (government_count() + 1) * sizeof(*adv->government_want));
 
  adv->wonder_city = 0;
 
  adv->wants_science = TRUE;
  adv->celebrate = FALSE;
  adv->max_num_cities = 10000;
}
 
/**********************************************************************/
void adv_data_close(struct player *pplayer)
{
  struct adv_data *adv = pplayer->server.adv;
 
  fc_assert_ret(NULL != adv);
 
  adv_data_phase_done(pplayer);
 
  if (adv->government_want != NULL) {
    free(adv->government_want);
  }
 
  if (adv->dipl.adv_dipl_slots != NULL) {
    players_iterate(aplayer) {
      adv_dipl_free(pplayer, aplayer);
      if (aplayer != pplayer) {
        adv_dipl_free(aplayer, pplayer);
      }
    } players_iterate_end;
    FC_FREE(adv->dipl.adv_dipl_slots);
  }
 
  if (adv != NULL) {
    free(adv);
  }
 
  pplayer->server.adv = NULL;
}
 
/**********************************************************************/
static void adv_dipl_new(const struct player *plr1,
                         const struct player *plr2)
{
  struct adv_dipl **dip_slot =
    plr1->server.adv->dipl.adv_dipl_slots + player_index(plr2);
 
  *dip_slot = fc_calloc(1, sizeof(struct adv_dipl));
}
 
/**********************************************************************/
static void adv_dipl_free(const struct player *plr1,
                          const struct player *plr2)
{
  struct adv_dipl **dip_slot =
    plr1->server.adv->dipl.adv_dipl_slots + player_index(plr2);
 
  if (*dip_slot != NULL) {
    FC_FREE(*dip_slot);
    *dip_slot = NULL;
  }
}
 
/**********************************************************************/
static struct adv_dipl *adv_dipl_get(const struct player *plr1,
                                     const struct player *plr2)
{
  struct adv_dipl **dip_slot =
    plr1->server.adv->dipl.adv_dipl_slots + player_index(plr2);
 
  return *dip_slot;
}
 
/**********************************************************************/
adv_want adv_gov_action_immunity_want(struct government *gov)
{
  adv_want bonus = 0;
 
  /* TODO: Individual and well balanced value. */
  action_iterate(act) {
    struct action *paction = action_by_number(act);
 
    if (!action_immune_government(gov, act)) {
      /* This government doesn't provide immunity against this
       * action. */
      continue;
    }
 
    switch (paction->result) {
    case ACTRES_ATTACK:
    case ACTRES_SPY_INCITE_CITY:
    case ACTRES_CONQUER_CITY:
      bonus += 4;
      break;
    case ACTRES_SPY_BRIBE_UNIT:
      bonus += 2;
      break;
    case ACTRES_TRANSFORM_TERRAIN:
      bonus += 1.5;
      break;
    case ACTRES_CULTIVATE:
    case ACTRES_PLANT:
      bonus += 0.3;
      break;
    case ACTRES_CONQUER_EXTRAS:
    case ACTRES_PILLAGE:
      bonus += 0.2;
      break;
    case ACTRES_HUT_ENTER:
    case ACTRES_HUT_FRIGHTEN:
      /* It is mine. My own. My precious. */
      bonus += 0.1;
      break;
    case ACTRES_SPY_INVESTIGATE_CITY:
    case ACTRES_SPY_POISON:
    case ACTRES_SPY_SPREAD_PLAGUE:
    case ACTRES_SPY_STEAL_GOLD:
    case ACTRES_SPY_SABOTAGE_CITY:
    case ACTRES_SPY_TARGETED_SABOTAGE_CITY:
    case ACTRES_SPY_SABOTAGE_CITY_PRODUCTION:
    case ACTRES_SPY_STEAL_TECH:
    case ACTRES_SPY_TARGETED_STEAL_TECH:
    case ACTRES_SPY_SABOTAGE_UNIT:
    case ACTRES_CAPTURE_UNITS:
    case ACTRES_STEAL_MAPS:
    case ACTRES_BOMBARD:
    case ACTRES_SPY_NUKE:
    case ACTRES_NUKE:
    case ACTRES_NUKE_UNITS:
    case ACTRES_DESTROY_CITY:
    case ACTRES_EXPEL_UNIT:
    case ACTRES_STRIKE_BUILDING:
    case ACTRES_STRIKE_PRODUCTION:
    case ACTRES_SPY_ATTACK:
      /* Being a target of this is usually undesirable */
      /* TODO: Individual and well balanced values. */
      bonus += 0.1;
      break;
 
    case ACTRES_UNIT_MOVE:
    case ACTRES_MARKETPLACE:
    case ACTRES_FOUND_CITY:
    case ACTRES_DISBAND_UNIT:
    case ACTRES_PARADROP:
    case ACTRES_PARADROP_CONQUER:
    case ACTRES_FORTIFY:
      /* Wants the ability to do this to it self. Don't want others
       * to target it. Do nothing since action_immune_government()
       * doesn't separate based on who the actor is. */
      break;
 
    case ACTRES_NONE:
      /* Ruleset defined */
      break;
 
    case ACTRES_ESTABLISH_EMBASSY:
    case ACTRES_TRADE_ROUTE:
    case ACTRES_JOIN_CITY:
    case ACTRES_HELP_WONDER:
    case ACTRES_DISBAND_UNIT_RECOVER:
    case ACTRES_HOME_CITY:
    case ACTRES_HOMELESS:
    case ACTRES_UPGRADE_UNIT:
    case ACTRES_AIRLIFT:
    case ACTRES_HEAL_UNIT:
    case ACTRES_ROAD:
    case ACTRES_CONVERT:
    case ACTRES_BASE:
    case ACTRES_MINE:
    case ACTRES_IRRIGATE:
    case ACTRES_CLEAN_POLLUTION:
    case ACTRES_CLEAN_FALLOUT:
    case ACTRES_TRANSPORT_ALIGHT:
    case ACTRES_TRANSPORT_UNLOAD:
    case ACTRES_TRANSPORT_DISEMBARK:
    case ACTRES_TRANSPORT_BOARD:
    case ACTRES_TRANSPORT_EMBARK:
      /* Could be good. An embassy gives permanent contact. A trade
       * route gives gold per turn. Join city gives population. Help
       * wonder gives shields. */
      /* TODO: Individual and well balanced values. */
      break;
    }
  } action_iterate_end;
 
  return bonus;
}
 
/**********************************************************************/
adv_want adv_gov_player_bonus_want(struct player *pplayer)
{
  adv_want bonus = 0;
 
  /* Bonuses for non-economic abilities. We increase val by
   * a very small amount here to choose govt in cases where
   * we have no cities yet. */
  bonus += get_player_bonus(pplayer, EFT_VETERAN_BUILD) > 0 ? 3 : 0;
  bonus += get_player_bonus(pplayer, EFT_INSPIRE_PARTISANS) > 0 ? 3 : 0;
  bonus += get_player_bonus(pplayer, EFT_RAPTURE_GROW) > 0 ? 2 : 0;
  bonus += get_player_bonus(pplayer, EFT_FANATICS) > 0 ? 3 : 0;
  bonus += get_player_bonus(pplayer, EFT_OUTPUT_INC_TILE) * 8;
 
  return bonus;
}
 
/**********************************************************************/
void adv_best_government(struct player *pplayer)
{
  struct adv_data *adv = adv_data_get(pplayer, NULL);
  int best_val = 0;
  struct government *current_gov = government_of_player(pplayer);
 
  adv->goal.govt.gov = current_gov;
  adv->goal.govt.val = 0;
  adv->goal.govt.req = A_UNSET;
  adv->goal.revolution = current_gov;
 
  if (has_handicap(pplayer, H_AWAY) || !pplayer->is_alive) {
    return;
  }
 
  if (adv->govt_reeval == 0) {
    const struct research *presearch = research_get(pplayer);
 
    governments_iterate(gov) {
      adv_want val = 0;
      bool override = FALSE;
 
      if (gov == game.government_during_revolution) {
        continue; /* pointless */
      }
      if (gov->ai.better
          && can_change_to_government(pplayer, gov->ai.better)) {
        continue; /* we have better governments available */
      }
 
      CALL_PLR_AI_FUNC(gov_value, pplayer, pplayer, gov, &val, &override);
 
      if (!override) {
        int dist;
        adv_want bonus = 0; /* in percentage */
        int revolution_turns;
 
        pplayer->government = gov;
        /* Ideally we should change tax rates here, but since
         * this is a rather big CPU operation, we'd rather not. */
        check_player_max_rates(pplayer);
        city_list_iterate(pplayer->cities, acity) {
          auto_arrange_workers(acity);
        } city_list_iterate_end;
        city_list_iterate(pplayer->cities, pcity) {
          val += adv_eval_calc_city(pcity, adv);
        } city_list_iterate_end;
 
        bonus += adv_gov_action_immunity_want(gov);
        bonus += adv_gov_player_bonus_want(pplayer);
 
        revolution_turns = get_player_bonus(pplayer, EFT_REVOLUTION_UNHAPPINESS);
        if (revolution_turns > 0) {
          bonus -= 6 / revolution_turns;
        }
 
        val += (val * bonus) / 100;
 
        /* FIXME: handle reqs other than technologies. */
        dist = 0;
        requirement_vector_iterate(&gov->reqs, preq) {
          if (VUT_ADVANCE == preq->source.kind) {
            int gut = research_goal_unknown_techs(presearch,
                                      advance_number(preq->source.value.advance));
 
            dist += MAX(1, gut);
          }
        } requirement_vector_iterate_end;
        val = amortize(val, dist);
      }
 
      adv->government_want[government_index(gov)] = val; /* Save want */
    } governments_iterate_end;
    /* Now reset our gov to it's real state. */
    pplayer->government = current_gov;
    city_list_iterate(pplayer->cities, acity) {
      auto_arrange_workers(acity);
    } city_list_iterate_end;
    if (player_is_cpuhog(pplayer)) {
      adv->govt_reeval = 1;
    } else {
      adv->govt_reeval = CLIP(5, city_list_size(pplayer->cities), 20);
    }
  }
  adv->govt_reeval--;
 
  /* Figure out which government is the best for us this turn. */
  governments_iterate(gov) {
    int gi = government_index(gov);
    if (adv->government_want[gi] > best_val 
        && can_change_to_government(pplayer, gov)) {
      best_val = adv->government_want[gi];
      adv->goal.revolution = gov;
    }
    if (adv->government_want[gi] > adv->goal.govt.val) {
      adv->goal.govt.gov = gov;
      adv->goal.govt.val = adv->government_want[gi];
 
      /* FIXME: handle reqs other than technologies. */
      adv->goal.govt.req = A_NONE;
      requirement_vector_iterate(&gov->reqs, preq) {
        if (VUT_ADVANCE == preq->source.kind) {
          adv->goal.govt.req = advance_number(preq->source.value.advance);
          break;
        }
      } requirement_vector_iterate_end;
    }
  } governments_iterate_end;
  /* Goodness of the ideal gov is calculated relative to the goodness of the
   * best of the available ones. */
  adv->goal.govt.val -= best_val;
}
 
/**********************************************************************/
bool adv_wants_science(struct player *pplayer)
{
  return adv_data_get(pplayer, NULL)->wants_science;
}
 
/**********************************************************************/
bool adv_is_player_dangerous(struct player *pplayer,
                             struct player *aplayer)
{
  struct adv_dipl *dip;
  enum diplstate_type ds;
  enum override_bool dang = NO_OVERRIDE;
 
  if (is_ai(pplayer)) {
    /* Give AI code possibility to decide itself */
    CALL_PLR_AI_FUNC(consider_plr_dangerous, pplayer, pplayer, aplayer, &dang);
  }
 
  if (dang == OVERRIDE_FALSE) {
    return FALSE;
  }
 
  if (dang == OVERRIDE_TRUE) {
    return TRUE;
  }
 
  if (pplayer == aplayer) {
    /* We always trust ourself */
    return FALSE;
  }
  
  ds = player_diplstate_get(pplayer, aplayer)->type;
  
  if (ds == DS_WAR || ds == DS_CEASEFIRE) {
    /* It's already a war or aplayer can declare it soon */
    return TRUE;
  }
 
  dip = adv_dipl_get(pplayer, aplayer);
 
  if (dip->allied_with_enemy) {
    /* Don't trust someone who will declare war on us soon */
    return TRUE;
  }
 
  if (player_diplstate_get(pplayer, aplayer)->has_reason_to_cancel > 0) {
    return TRUE;
  }
 
  if (pplayer->ai_common.love[player_index(aplayer)] < MAX_AI_LOVE / 10) {
    /* We don't trust players who we don't like. Note that 
     * aplayer's units inside pplayer's borders decreases AI's love */
    return TRUE;
  }
  
  return FALSE;
}