Working on Attacks of Opportunity.

5 files changed, 252 insertions, 57 deletions

diff --git a/src/battle/mechanic/btl_turn_actions_management.erl b/src/battle/mechanic/btl_turn_actions_management.erl
index d33fbad..eefe812 100644
--- a/src/battle/mechanic/btl_turn_actions_management.erl
+++ b/src/battle/mechanic/btl_turn_actions_management.erl
@@ -37,17 +37,48 @@ deactivate_character (Update) ->
 
    S1Update.
 
--spec handle_action
-(
-   btl_action:type(),
-   btl_character_turn_update:type()
-)
--> btl_character_turn_update:type().
-handle_action (BattleAction, Update) ->
-   case btl_action:get_category(BattleAction) of
-      move -> btl_turn_actions_move:handle(BattleAction, Update);
-      switch_weapon -> btl_turn_actions_switch_weapon:handle(Update);
-      attack -> btl_turn_actions_attack:handle(BattleAction, Update)
+-spec main_character_is_alive
+   (
+      btl_character_turn_update:type()
+   )
+   -> {boolean(), btl_character_turn_update:type()}.
+main_character_is_alive (Update) ->
+   {S0Update, MainCharacter} = btl_character_turn_update:get_character(Update),
+   {btl_character:get_is_alive(MainCharacter), S0Update}.
+
+-spec handle_actions
+   (
+      list(btl_action:type()),
+      btl_character_turn_update:type()
+   )
+   -> btl_character_turn_update:type().
+handle_actions ([], Update) -> Update;
+handle_actions ([BattleAction|FutureBattleActions], Update) ->
+   {MainCharacterIsAlive, S0Update} = main_character_is_alive(Update),
+
+   ActionResult =
+      case {MainCharacterIsAlive, btl_action:get_category(BattleAction)} of
+         {false, _} -> {ok, S0Update};
+         {true, move} -> btl_turn_actions_move:handle(BattleAction, S0Update);
+         {true, switch_weapon} ->
+            btl_turn_actions_switch_weapon:handle(S0Update);
+         {true, attack} ->
+            btl_turn_actions_attack:handle(BattleAction, S0Update);
+         {true, interrupted_move} ->
+            btl_turn_actions_move:handle(BattleAction, S0Update);
+         {true, defend} ->
+            % TODO: Attack of Opportunity
+            Update
+      end,
+
+   case ActionResult of
+      {ok, NewUpdate} -> handle_actions(FutureBattleActions, NewUpdate);
+      {events, NewEvents, NewUpdate} ->
+         handle_actions
+         (
+            (NewEvents ++ FutureBattleActions),
+            NewUpdate
+         )
    end.
 
 -spec update_timeline
@@ -98,7 +129,7 @@ update_timeline (Update) ->
 handle (Update, Request) ->
    Actions = btl_character_turn_request:get_actions(Request),
 
-   S0Update = lists:foldl(fun handle_action/2, Update, Actions),
+   S0Update = handle_actions(Actions, Update),
    S1Update = deactivate_character(S0Update),
    S2Update = update_timeline(S1Update),
    S3Update = btl_turn_progression:handle(S2Update),
diff --git a/src/battle/mechanic/turn_action/btl_turn_actions_attack.erl b/src/battle/mechanic/turn_action/btl_turn_actions_attack.erl
index e36c7e3..af4c53b 100644
--- a/src/battle/mechanic/turn_action/btl_turn_actions_attack.erl
+++ b/src/battle/mechanic/turn_action/btl_turn_actions_attack.erl
@@ -151,7 +151,7 @@ get_attack_sequence (Character, TargetCharacter) ->
       btl_action:type(),
       btl_character_turn_update:type()
    )
-   -> btl_character_turn_update:type().
+   -> {ok, btl_character_turn_update:type()}.
 handle (BattleAction, Update) ->
    {S0Update, Battle} = btl_character_turn_update:get_battle(Update),
    {S1Update, Character} = btl_character_turn_update:get_character(S0Update),
@@ -336,4 +336,4 @@ handle (BattleAction, Update) ->
             )
       end,
 
-   S6Update.
+   {ok, S6Update}.
diff --git a/src/battle/mechanic/turn_action/btl_turn_actions_move.erl b/src/battle/mechanic/turn_action/btl_turn_actions_move.erl
index a0cd138..70b42c9 100644
--- a/src/battle/mechanic/turn_action/btl_turn_actions_move.erl
+++ b/src/battle/mechanic/turn_action/btl_turn_actions_move.erl
@@ -18,16 +18,23 @@
 %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
 -spec cross
    (
+      non_neg_integer(),
       shr_map:type(),
       list(shr_location:type()),
       list(shr_direction:enum()),
       non_neg_integer(),
       shr_location:type()
    )
-   -> {shr_location:type(), non_neg_integer()}.
-cross (_Map, _ForbiddenLocations, [], Cost, Location) ->
-   {Location, Cost};
-cross (Map, ForbiddenLocations, [Step|NextSteps], Cost, Location) ->
+   ->
+   {
+      shr_location:type(),
+      list(shr_direction:type()),
+      non_neg_integer(),
+      list(shr_map_marker:type())
+   }.
+cross (_PlayerIX, _Map, _ForbiddenLocations, [], Cost, Location) ->
+   {Location, [], Cost, []};
+cross (PlayerIX, Map, ForbiddenLocations, [Step|NextSteps], Cost, Location) ->
    NextLocation = shr_location:apply_direction(Step, Location),
    NextTileInstance = shr_map:get_tile_instance(NextLocation, Map),
    NextTileClassID = shr_tile_instance:get_tile_id(NextTileInstance),
@@ -43,20 +50,60 @@ cross (Map, ForbiddenLocations, [Step|NextSteps], Cost, Location) ->
          ForbiddenLocations
       ),
 
-   IsForbidden = false,
+   false = IsForbidden,
+
+   Interruptions =
+      list:foldl
+      (
+         fun (MarkerName, CurrentInterruptions) ->
+            case shr_map:get_marker(MarkerName, Map) of
+               {ok, Marker} ->
+                  case shr_map_marker:interrupts_movement(PlayerIX, Marker) of
+                     true -> [Marker|CurrentInterruptions];
+                     _ -> CurrentInterruptions
+                  end;
+
+               error ->
+                  %% TODO: Error.
+                  CurrentInterruptions
+            end
+         end,
+         [],
+         shr_tile_instance:get_triggers(NextTileInstance)
+      ),
+
+   case Interruptions of
+      [] ->
+         cross
+         (
+            PlayerIX,
+            Map,
+            ForbiddenLocations,
+            NextSteps,
+            NextCost,
+            NextLocation
+         );
 
-   cross(Map, ForbiddenLocations, NextSteps, NextCost, NextLocation).
+      _ -> {NextLocation, NextSteps, NextCost, Interruptions}
+   end.
 
 -spec cross
    (
+      non_neg_integer(),
       shr_map:type(),
       list(shr_location:type()),
       list(shr_direction:enum()),
       shr_location:type()
    )
-   -> {shr_location:type(), non_neg_integer()}.
-cross (Map, ForbiddenLocations, Path, Location) ->
-   cross(Map, ForbiddenLocations, Path, 0, Location).
+   ->
+   {
+      shr_location:type(),
+      list(shr_direction:type()),
+      non_neg_integer(),
+      list(shr_map_marker:type())
+   }.
+cross (PlayerIX, Map, ForbiddenLocations, Path, Location) ->
+   cross(PlayerIX, Map, ForbiddenLocations, Path, 0, Location).
 
 -spec get_path_cost_and_destination
    (
@@ -67,6 +114,8 @@ cross (Map, ForbiddenLocations, Path, Location) ->
    {
       non_neg_integer(),
       shr_location:type(),
+      list(shr_direction:type()),
+      list(shr_map_marker:type()),
       btl_character_turn_update:type()
    }.
 get_path_cost_and_destination (Update, Path) ->
@@ -75,6 +124,9 @@ get_path_cost_and_destination (Update, Path) ->
    CharacterIX = btl_character_turn_update:get_character_ix(S1Update),
    Map = btl_battle:get_map(Battle),
 
+   % FIXME: This is recalculated at every move action, despite there be no need
+   % to: The client will not allow the character to go somewhere that would
+   % only be freed because of an event.
    ForbiddenLocations =
       orddict:fold
       (
@@ -91,42 +143,35 @@ get_path_cost_and_destination (Update, Path) ->
          btl_battle:get_characters(Battle)
       ),
 
-   {NewLocation, Cost} =
+   {NewLocation, RemainingPath, Cost, Interruptions} =
       cross
       (
+         btl_character:get_player_index(Character),
          Map,
          ForbiddenLocations,
          Path,
          btl_character:get_location(Character)
       ),
 
-   {Cost, NewLocation, S1Update}.
+   {Cost, NewLocation, RemainingPath, Interruptions, S1Update}.
 
--spec assert_character_can_move
+-spec get_movement_points
    (
-      btl_character:type(),
-      non_neg_integer()
+      btl_action:type(),
+      btl_character:type()
    )
-   -> ('ok' | 'error').
-assert_character_can_move (Char, Cost) ->
-   CharacterMovementPoints =
-      shr_statistics:get_movement_points
-      (
-         shr_character:get_statistics
+   -> non_neg_integer().
+get_movement_points (Action, Char) ->
+   case btl_action:get_category(Action) of
+      interrupted_move -> btl_action:get_movement_points(Action);
+      _ ->
+         shr_statistics:get_movement_points
          (
-            btl_character:get_base_character(Char)
+            shr_character:get_statistics
+            (
+               btl_character:get_base_character(Char)
+            )
          )
-      ),
-
-   case (Cost =< CharacterMovementPoints) of
-      true -> ok;
-      false ->
-         io:format
-         (
-            "~n[E] Character trying to move ~p dist with ~p points.~n",
-            [Cost, CharacterMovementPoints]
-         ),
-         error
    end.
 
 -spec commit_move
@@ -183,14 +228,51 @@ commit_move (Character, Update, Path, NewLocation) ->
       btl_action:type(),
       btl_character_turn_update:type()
    )
-   -> btl_character_turn_update:type().
+   ->
+   (
+      {'ok', btl_character_turn_update:type()}
+      | {'events', list(btl_action:type()), btl_character_turn_update:type()}
+   ).
 handle (BattleAction, Update) ->
    {S0Update, Character} = btl_character_turn_update:get_character(Update),
+
    Path = btl_action:get_path(BattleAction),
 
-   {PathCost, NewLocation, S1Update} =
+   {PathCost, NewLocation, RemainingPath, Interruptions, S1Update} =
       get_path_cost_and_destination(S0Update, Path),
 
-   ok = assert_character_can_move(Character, PathCost),
+   MovementPoints = get_movement_points(BattleAction, Character),
+
+   true = (MovementPoints >= PathCost),
+
+   S2Update = commit_move(Character, S1Update, Path, NewLocation),
 
-   commit_move(Character, S1Update, Path, NewLocation).
+   case RemainingPath of
+      [] -> {ok, S2Update};
+      _ ->
+         {events,
+            (
+               lists:foldl
+               (
+                  fun (Marker, CurrentActions) ->
+                     (
+                        btl_action:from_map_marker(Character, Marker)
+                        ++
+                        CurrentActions
+                     )
+                  end,
+                  [],
+                  Interruptions
+               )
+               ++
+               [
+                  btl_action:new_interrupted_move
+                  (
+                     RemainingPath,
+                     (MovementPoints - PathCost)
+                  )
+               ]
+            ),
+            S2Update
+         }
+   end.
diff --git a/src/battle/mechanic/turn_action/btl_turn_actions_switch_weapon.erl b/src/battle/mechanic/turn_action/btl_turn_actions_switch_weapon.erl
index 24b361a..8e4aeab 100644
--- a/src/battle/mechanic/turn_action/btl_turn_actions_switch_weapon.erl
+++ b/src/battle/mechanic/turn_action/btl_turn_actions_switch_weapon.erl
@@ -24,7 +24,7 @@
    (
       btl_character_turn_update:type()
    )
-   -> btl_character_turn_update:type().
+   -> {'ok', btl_character_turn_update:type()}.
 handle (Update) ->
    {S0Update, Character} = btl_character_turn_update:get_character(Update),
    CharacterIX = btl_character_turn_update:get_character_ix(S0Update),
@@ -52,4 +52,4 @@ handle (Update) ->
          S1Update
       ),
 
-   S2Update.
+   {ok, S2Update}.
diff --git a/src/battle/struct/btl_action.erl b/src/battle/struct/btl_action.erl
index 34dd46e..52f41d8 100644
--- a/src/battle/struct/btl_action.erl
+++ b/src/battle/struct/btl_action.erl
@@ -13,6 +13,15 @@
 
 -record
 (
+   interrupted_move,
+   {
+      path :: list(shr_direction:enum()),
+      movement_points :: non_neg_integer()
+   }
+).
+
+-record
+(
    switch_weapon,
    {
    }
@@ -26,8 +35,32 @@
    }
 ).
 
--type category() :: ('move' | 'switch_weapon' | 'attack' | 'nothing').
--opaque type() :: (#move{} | #switch_weapon{} | #attack{}).
+-record
+(
+   defend,
+   {
+      target_ix :: non_neg_integer()
+   }
+).
+
+
+-type category() ::
+   (
+      'move'
+      | 'interrupted_move'
+      | 'switch_weapon'
+      | 'attack'
+      | 'defend'
+      | 'nothing'
+   ).
+-opaque type() ::
+   (
+      #move{}
+      | #interrupted_move{}
+      | #switch_weapon{}
+      | #attack{}
+      | #defend{}
+   ).
 
 -export_type([category/0, type/0]).
 
@@ -37,6 +70,7 @@
 -export
 (
    [
+      from_map_marker/2,
       maybe_decode_move/1,
       maybe_decode_weapon_switch/1,
       maybe_decode_attack/1,
@@ -47,7 +81,15 @@
 -export
 (
    [
+      new_interrupted_move/2
+   ]
+).
+
+-export
+(
+   [
       get_path/1,
+      get_movement_points/1,
       get_target_ix/1,
       get_category/1
    ]
@@ -86,17 +128,57 @@ can_follow (_, _) -> false.
 -spec get_path (type()) -> list(shr_direction:type()).
 get_path (Action) when is_record(Action, move) ->
    Action#move.path;
+get_path (Action) when is_record(Action, interrupted_move) ->
+   Action#interrupted_move.path;
 get_path (_) ->
    [].
 
+-spec get_movement_points (type()) -> non_neg_integer().
+get_movement_points (Action) when is_record(Action, interrupted_move) ->
+   Action#interrupted_move.movement_points;
+get_movement_points (_) -> 0.
+
 -spec get_target_ix (type()) -> non_neg_integer().
 get_target_ix (Action) when is_record(Action, attack) ->
    Action#attack.target_ix;
+get_target_ix (Action) when is_record(Action, defend) ->
+   Action#defend.target_ix;
 get_target_ix (_) ->
-   [].
+   0.
+
+-spec new_interrupted_move
+   (
+      list(shr_direction:type()),
+      non_neg_integer()
+   )
+   -> type().
+new_interrupted_move (Path, MovementPoints) ->
+   #interrupted_move{ path = Path, movement_points = MovementPoints }.
 
 -spec get_category (type()) -> category().
 get_category (Action) when is_record(Action, attack) -> attack;
 get_category (Action) when is_record(Action, move) -> move;
-get_category (Action) when is_record(Action, switch_weapon) -> switch_weapon.
-
+get_category (Action) when is_record(Action, switch_weapon) -> switch_weapon;
+get_category (Action) when is_record(Action, interrupted_move) ->
+   interrupted_move;
+get_category (Action) when is_record(Action, defend) ->
+  defend.
+
+-spec from_map_marker
+   (
+      btl_character:type(),
+      shr_map_marker:type()
+   )
+   -> list(type()).
+from_map_marker (_Character, Marker) ->
+   case shr_map_marker:get_category(Marker) of
+      matk ->
+         [
+            #defend
+            {
+               target_ix = shr_map_marker:get_character_index(Marker)
+            }
+         ];
+
+      _ -> []
+   end.