-module(blc_armor).

-include("tacticians/attributes.hrl").

-define
(
   SPENDABLE_ARMOR_POINTS,
   (
      (
         ?ATTRIBUTE_DAMAGE_MODIFIER_COST
         * (?ATTRIBUTE_DAMAGE_MODIFIER_DEFAULT - ?ATTRIBUTE_DAMAGE_MODIFIER_MIN)
      )
      +
      (
         ?ATTRIBUTE_DODGE_CHANCE_COST
         * (?ATTRIBUTE_DODGE_CHANCE_DEFAULT - ?ATTRIBUTE_DODGE_CHANCE_MIN)
      )
      +
      (
         ?ATTRIBUTE_MOVEMENT_POINTS_COST
         * (?ATTRIBUTE_MOVEMENT_POINTS_DEFAULT - ?ATTRIBUTE_MOVEMENT_POINTS_MIN)
      )
      +
      (
         ?ATTRIBUTE_HEALTH_COST
         * (?ATTRIBUTE_HEALTH_DEFAULT - ?ATTRIBUTE_HEALTH_MIN)
      )
      +
      (
         ?ATTRIBUTE_DEFENSE_SCORE_COST
         * (?ATTRIBUTE_DEFENSE_SCORE_DEFAULT - ?ATTRIBUTE_DEFENSE_SCORE_MIN)
      )
   )
).

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% TYPES %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-record
(
   proto_armor,
   {
      omnimods :: shr_omnimods:type(),
      defense_coef :: list(blc_damage_type:coefficient()),
      defense_score :: non_neg_integer(),
      remaining_points :: non_neg_integer()
   }
).

-opaque type() :: #proto_armor{}.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% EXPORTS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-export_type([type/0]).

-export
(
   [
      increase_health_by/2,
      increase_damage_modifier_by/2,
      increase_dodge_chance_by/2,
      increase_defense_score_by/2,
      increase_movement_points_by/2,
      increase_health_for/2,
      increase_damage_modifier_for/2,
      increase_dodge_chance_for/2,
      increase_movement_points_for/2,
      increase_defense_score_for/2,
      set_defense_coefficients/2
   ]
).

-export
(
   [
      new/1,
      get_remaining_points/1
   ]
).

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% LOCAL FUNCTIONS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-spec increase_attribute_by
   (
      shr_attributes:enum(),
      non_neg_integer(),
      type()
   )
   -> ({ok, type()} | blc_error:type()).
increase_attribute_by (Attribute, S0Amount, Armor) ->
   CurrentOmnimods = Armor#proto_armor.omnimods,
   CurrentValue =
      shr_omnimods:get_attribute_modifier(Attribute, CurrentOmnimods),

   {_AttMin, _AttDef, AttMax, AttCost} = blc_attribute:get_info(Attribute),

   S1Amount =
      case ((CurrentValue + S0Amount) > AttMax) of
         true -> (AttMax - CurrentValue);
         false -> S0Amount
      end,

   Cost = (S1Amount * AttCost),
   RemainingPoints = Armor#proto_armor.remaining_points,

   case (Cost > RemainingPoints) of
      true -> {error, balance, RemainingPoints, Cost};
      false ->
         {
            ok,
            Armor#proto_armor
            {
               remaining_points = (RemainingPoints - Cost),
               omnimods =
                  shr_omnimods:mod_attribute_modifier
                  (
                     Attribute,
                     S1Amount,
                     Armor#proto_armor.omnimods
                  )
            }
         }
   end.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% EXPORTED FUNCTIONS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-spec increase_health_by
   (
      non_neg_integer(),
      type()
   )
   -> ({ok, type()} | blc_error:type()).
increase_health_by (Amount, Armor) ->
   increase_attribute_by(?ATTRIBUTE_HEALTH, Amount, Armor).

-spec increase_damage_modifier_by
   (
      non_neg_integer(),
      type()
   )
   -> ({ok, type()} | blc_error:type()).
increase_damage_modifier_by (Amount, Armor) ->
   increase_attribute_by(?ATTRIBUTE_DAMAGE_MODIFIER, Amount, Armor).

-spec increase_dodge_chance_by
   (
      non_neg_integer(),
      type()
   )
   -> ({ok, type()} | blc_error:type()).
increase_dodge_chance_by (Amount, Armor) ->
   increase_attribute_by(?ATTRIBUTE_DODGE_CHANCE, Amount, Armor).

-spec increase_movement_points_by
   (
      non_neg_integer(),
      type()
   )
   -> ({ok, type()} | blc_error:type()).
increase_movement_points_by (Amount, Armor) ->
   increase_attribute_by(?ATTRIBUTE_MOVEMENT_POINTS, Amount, Armor).

-spec increase_defense_score_by
   (
      non_neg_integer(),
      type()
   )
   -> ({ok, type()} | blc_error:type()).
increase_defense_score_by (S0Amount, Armor) ->
   CurrentValue = Armor#proto_armor.defense_score,
   S0NewValue = CurrentValue + S0Amount,
   {S1Amount, S1NewValue} =
      case (S0NewValue > ?ATTRIBUTE_DEFENSE_SCORE_MAX) of
         false -> {S0Amount, S0NewValue};
         true ->
            {
               (?ATTRIBUTE_DEFENSE_SCORE_MAX - CurrentValue),
               ?ATTRIBUTE_DEFENSE_SCORE_MAX
            }
      end,

   Cost = (S1Amount * ?ATTRIBUTE_DEFENSE_SCORE_COST),
   RemainingPoints = Armor#proto_armor.remaining_points,

   case (Cost > RemainingPoints) of
      true -> {error, balance, RemainingPoints, Cost};
      false ->
         {
            ok,
            Armor#proto_armor
            {
               remaining_points = (RemainingPoints - Cost),
               defense_score = S1NewValue,
               omnimods =
                  shr_omnimods:set_defense_modifiers
                  (
                     blc_damage_type:generate_entries_from_score
                     (
                        S1NewValue,
                        Armor#proto_armor.defense_coef
                     ),
                     Armor#proto_armor.omnimods
                  )
            }
         }
   end.

-spec set_defense_coefficients
   (
      list(blc_damage_type:coefficient()),
      type()
   )
   -> type().
set_defense_coefficients (Coefficients, Armor) ->
   NewCoefs = blc_damage_type:sort_entries(Coefficients),

   Armor#proto_armor
   {
      defense_coef = NewCoefs,
      omnimods =
         shr_omnimods:set_defense_modifiers
         (
            blc_damage_type:generate_entries_from_score
            (
               Armor#proto_armor.defense_score,
               NewCoefs
            ),
            Armor#proto_armor.omnimods
         )
   }.


-spec new (list(blc_damage_type:coefficient())) -> type().
new (Coefficients) ->
   SortedCoefficients = blc_damage_type:sort_entries(Coefficients),

   #proto_armor
   {
      omnimods =
         shr_omnimods:new
         (
            [
               {?ATTRIBUTE_HEALTH, ?ATTRIBUTE_HEALTH_MIN},
               {?ATTRIBUTE_DAMAGE_MODIFIER, ?ATTRIBUTE_DAMAGE_MODIFIER_MIN},
               {?ATTRIBUTE_DODGE_CHANCE, ?ATTRIBUTE_DODGE_CHANCE_MIN},
               {?ATTRIBUTE_MOVEMENT_POINTS, ?ATTRIBUTE_MOVEMENT_POINTS_MIN}
            ],
            [],
            blc_damage_type:generate_entries_from_score
            (
               ?ATTRIBUTE_DEFENSE_SCORE_MIN,
               SortedCoefficients
            )
         ),

      defense_coef = SortedCoefficients,
      defense_score = ?ATTRIBUTE_DEFENSE_SCORE_MIN,
      remaining_points = ?SPENDABLE_ARMOR_POINTS
   }.

-spec increase_health_for
   (
      non_neg_integer(),
      type()
   )
   -> ({ok, type()} | blc_error:type()).
increase_health_for (GivenPoints, Armor) ->
   AmountOfIncrease = trunc(GivenPoints / ?ATTRIBUTE_HEALTH_COST),
   increase_health_by(AmountOfIncrease, Armor).

-spec increase_damage_modifier_for
   (
      non_neg_integer(),
      type()
   )
   -> ({ok, type()} | blc_error:type()).
increase_damage_modifier_for (GivenPoints, Armor) ->
   AmountOfIncrease = trunc(GivenPoints / ?ATTRIBUTE_DAMAGE_MODIFIER_COST),
   increase_damage_modifier_by(AmountOfIncrease, Armor).

-spec increase_dodge_chance_for
   (
      non_neg_integer(),
      type()
   )
   -> ({ok, type()} | blc_error:type()).
increase_dodge_chance_for (GivenPoints, Armor) ->
   AmountOfIncrease = trunc(GivenPoints / ?ATTRIBUTE_DODGE_CHANCE_COST),
   increase_dodge_chance_by(AmountOfIncrease, Armor).

-spec increase_movement_points_for
   (
      non_neg_integer(),
      type()
   )
   -> ({ok, type()} | blc_error:type()).
increase_movement_points_for (GivenPoints, Armor) ->
   AmountOfIncrease = trunc(GivenPoints / ?ATTRIBUTE_MOVEMENT_POINTS_COST),
   increase_movement_points_by(AmountOfIncrease, Armor).

-spec increase_defense_score_for
   (
      non_neg_integer(),
      type()
   )
   -> ({ok, type()} | blc_error:type()).
increase_defense_score_for (GivenPoints, Armor) ->
   AmountOfIncrease = trunc(GivenPoints / ?ATTRIBUTE_DEFENSE_SCORE_COST),
   increase_defense_score_by(AmountOfIncrease, Armor).

-spec get_remaining_points (type()) -> non_neg_integer().
get_remaining_points (Armor) -> Armor#proto_armor.remaining_points.