Camp takeovers

data/json/effects_on_condition/misc_effect_on_condition.json

@@ -162,5 +162,35 @@
     "id": "morale_dislikes_sewer",
     "type": "morale_type",
     "text": "Dislikes being in sewer"
+  },
+  {
+    "type": "effect_on_condition",
+    "id": "EOC_TOOK_OVER_CAMP_NOTICE",
+    "eoc_type": "EVENT",
+    "required_event": "camp_taken_over",
+    "condition": { "expects_vars": [ "old_owner", "new_owner", "camp_name", "was_violent" ] },
+    "effect": [
+      {
+        "if": { "compare_string": [ "your_followers", { "context_val": "new_owner" } ] },
+        "then": {
+          "queue_eocs": {
+            "id": "EOC_camp_rumor_spread",
+            "effect": { "u_message": "Rumors of your takeover of <context_val:camp_name> have begun to spread…", "type": "mixed" }
+          },
+          "time_in_future": [ "7 days", "14 days" ]
+        },
+        "else": [
+          {
+            "//": "Don't bother player unless they even have a camp.",
+            "if": "u_has_camp",
+            "then": {
+              "u_message": "While you've been out of contact with the powers of <context_val:camp_name> it's been taken over by its enemies.",
+              "popup": true,
+              "type": "bad"
+            }
+          }
+        ]
+      }
+    ]
   }
 ]

src/basecamp.cpp

@@ -19,6 +19,7 @@
 #include "clzones.h"
 #include "color.h"
 #include "debug.h"
+#include "event_bus.h"
 #include "faction.h"
 #include "faction_camp.h"
 #include "game.h"
@@ -28,6 +29,7 @@
 #include "map.h"
 #include "map_iterator.h"
 #include "mapdata.h"
+#include "messages.h"
 #include "npc.h"
 #include "output.h"
 #include "overmap.h"
@@ -841,6 +843,76 @@ faction_id basecamp::get_owner()
     return owner;
 }
 
+void basecamp::handle_takeover_by( faction_id new_owner, bool violent_takeover )
+{
+    get_event_bus().send<event_type::camp_taken_over>( get_owner(), new_owner, name, violent_takeover );
+
+    // If anyone was somehow assigned here, they aren't any longer.
+    assigned_npcs.clear();
+    camp_workers.clear();
+
+    add_msg_debug( debugmode::DF_CAMPS, "Camp %s owned by %s is being taken over by %s!",
+                   name, fac()->name, new_owner->name );
+
+    if( !violent_takeover ) {
+        set_owner( new_owner );
+        return;
+    }
+
+    // Since it was violent, the old owner is going to be upset.
+    // Currently only handles player faction, and very bluntly.
+    if( new_owner == get_player_character().get_faction()->id ) {
+        fac()->likes_u -= 100;
+        fac()->trusts_u -= 100;
+    }
+
+    int num_of_owned_camps = 0;
+    // Go over all camps in existence and count the ones belonging to current owner
+    // TODO: Remove this when camps stop being stored on the player
+    for( tripoint_abs_omt camp_loc : get_player_character().camps ) {
+        std::optional<basecamp *> bcp = overmap_buffer.find_camp( camp_loc.xy() );
+        if( !bcp ) {
+            continue;
+        }
+        basecamp *checked_camp = *bcp;
+        // Note: Will count current basecamp object as well
+        if( checked_camp->get_owner() == get_owner() ) {
+            add_msg_debug( debugmode::DF_CAMPS,
+                           "Camp %s at %s is owned by %s, adding it to plunder calculations.",
+                           checked_camp->name, checked_camp->camp_omt_pos().to_string(), get_owner()->name );
+            num_of_owned_camps++;
+        }
+    }
+
+    if( num_of_owned_camps < 1 ) {
+        debugmsg( "Tried to take over a camp owned by %s, but they somehow own no camps!  Is the owner's faction id no longer valid?",
+                  get_owner().c_str() );
+        // Also abort the rest
+        set_owner( new_owner );
+        return;
+    }
+
+    // The faction taking over also seizes resources proportional to the number of camps the previous owner had
+    // e.g. a single-camp faction has its entire stockpile plundered, a 10-camp faction has 10% transferred
+    nutrients captured_with_camp = fac()->food_supply / num_of_owned_camps;
+    nutrients taken_from_camp = -captured_with_camp;
+    camp_food_supply( taken_from_camp );
+    add_msg_debug( debugmode::DF_CAMPS,
+                   "Food supplies of %s plundered by %d kilocalories! Total food supply reduced to %d kilocalories after losing %.1f%% of their camps.",
+                   fac()->name, captured_with_camp.kcal(), fac()->food_supply.kcal(),
+                   1.0 / static_cast<double>( num_of_owned_camps ) * 100.0 );
+    set_owner( new_owner );
+    int previous_days_of_food = camp_food_supply_days( MODERATE_EXERCISE );
+    camp_food_supply( captured_with_camp );
+    add_msg_debug( debugmode::DF_CAMPS,
+                   "Food supply of new owner %s has increased to %d kilocalories due to takeover of camp %s!",
+                   fac()->name, new_owner->food_supply.kcal(), name );
+    if( new_owner == get_player_character().get_faction()->id ) {
+        popup( _( "Through your looting of %s you found %d days worth of food and other resources." ),
+               name, camp_food_supply_days( MODERATE_EXERCISE ) - previous_days_of_food );
+    }
+}
+
 void basecamp::form_crafting_inventory()
 {
     map &here = get_camp_map();

src/basecamp.h

@@ -275,6 +275,10 @@ class basecamp
         int camp_morale( int change = 0 ) const;
 
         bool allowed_access_by( Character &guy, bool water_request = false ) const;
+        /* Transfers ownership of a camp and send an event signalling it. If violent_takeover, also applies relation
+        * maluses and transfers a proportional amount of the previous owner's food/resources to the new owner.
+        */
+        void handle_takeover_by( faction_id new_owner, bool violent_takeover );
         // recipes, gathering, and craft support functions
         // from a direction
         std::map<recipe_id, translation> recipe_deck( const point &dir ) const;

src/iexamine.cpp

@@ -1984,6 +1984,28 @@ void iexamine::bulletin_board( Character &you, const tripoint &examp )
     if( bcp ) {
         basecamp *temp_camp = *bcp;
         if( !temp_camp->allowed_access_by( you ) ) {
+            if( !you.is_avatar() ) {
+                return; // One day, NPCs may be able to use bulletin boards
+            }
+            // Checks the reality bubble for NPCs
+            std::vector<shared_ptr_fast<npc>> nearby_npcs = overmap_buffer.get_npcs_near_player( HALF_MAPSIZE );
+            bool unoccupied_camp = true;
+            for( npc_ptr &some_guy : nearby_npcs ) {
+                if( !some_guy ) {
+                    continue;
+                } else if( some_guy->get_faction()->id == temp_camp->get_owner() ) {
+                    unoccupied_camp = false;
+                }
+            }
+            if( unoccupied_camp &&
+                query_yn( _( "There's nobody here to protect %s.  Do you want to claim ownership?" ),
+                          temp_camp->camp_name() ) ) {
+                bool plunder = query_yn(
+                                   _( "Take whatever you can find from the stores?  This may anger %s and their allies." ),
+                                   temp_camp->get_owner()->name );
+                temp_camp->handle_takeover_by( you.get_faction()->id, plunder );
+                return;
+            }
             you.add_msg_if_player( _( "You don't run this camp, the board is useless to you." ) );
             return;
         }