-module(sh_weapon).

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% TYPES %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-opaque id() :: non_neg_integer().

-type range_type() :: 'ranged' | 'melee'.
-type range_modifier() :: 'long' | 'short'.
-type damage_type() :: 'slash' | 'pierce' | 'blunt'.
-type damage_modifier() :: 'heavy' | 'light'.

-record
(
   weapon,
   {
      id :: id(),
      name :: binary(),
      range_type :: range_type(),
      range_mod :: range_modifier(),
      damage_type :: damage_type(),
      damage_mod :: damage_modifier(),
      coef :: float()
   }
).

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

-export_type([type/0, id/0]).
-export_type
(
   [
      range_type/0,
      range_modifier/0,
      damage_type/0,
      damage_modifier/0
   ]
).

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% EXPORTS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%% Accessors
-export
(
   [
      get_id/1,
      get_name/1,
      get_range_type/1,
      get_range_modifier/1,
      get_damage_type/1,
      get_damage_modifier/1,
      get_coefficient/1,
      get_ranges/1,
      get_damages/1
   ]
).

-export
(
   [
      random_id/0,
      from_id/1,
      can_parry/1,
      apply_to_attributes/2
   ]
).

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% LOCAL FUNCTIONS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
-spec ranges_of_type
   (
      range_type(),
      range_modifier()
   )
   -> {non_neg_integer(), non_neg_integer()}.
ranges_of_type (ranged, long) -> {2, 6};
ranges_of_type (ranged, short) -> {1, 4};
ranges_of_type (melee, long) -> {0, 2};
ranges_of_type (melee, short) -> {0, 1}.

-spec damages_of_type
   (
      range_type(),
      damage_modifier()
   )
   -> {non_neg_integer(), non_neg_integer()}.
damages_of_type (ranged, heavy) -> {10, 25};
damages_of_type (ranged, light) -> {5, 20};
damages_of_type (melee, heavy) -> {20, 35};
damages_of_type (melee, light) -> {15, 30}.

%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%% EXPORTED FUNCTIONS %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
%%%% Accessors
-spec get_id (type()) -> id().
get_id (Wp) -> Wp#weapon.id.

-spec get_name (type()) -> binary().
get_name (Wp) -> Wp#weapon.name.

-spec get_range_type (type()) -> range_type().
get_range_type (Wp) -> Wp#weapon.range_type.

-spec get_range_modifier (type()) -> range_modifier().
get_range_modifier (Wp) -> Wp#weapon.range_mod.

-spec get_damage_type (type()) -> damage_type().
get_damage_type (Wp) -> Wp#weapon.damage_type.

-spec get_damage_modifier (type()) -> damage_modifier().
get_damage_modifier (Wp) -> Wp#weapon.damage_mod.

-spec get_coefficient (type()) -> float().
get_coefficient (Wp) -> Wp#weapon.coef.

-spec get_ranges (type()) -> {non_neg_integer(), non_neg_integer()}.
get_ranges (Wp) ->
   ranges_of_type(Wp#weapon.range_type, Wp#weapon.range_mod).

-spec get_damages (type()) -> {non_neg_integer(), non_neg_integer()}.
get_damages (Wp) ->
   Coef = Wp#weapon.coef,
   {Min, Max} = damages_of_type(Wp#weapon.range_type, Wp#weapon.damage_mod),
   {sh_math_util:ceil(Min * Coef), sh_math_util:ceil(Max * Coef)}.

-spec can_parry (type()) -> boolean().
can_parry (Wp) -> (Wp#weapon.range_type == melee).

-spec from_id (id()) -> type().
from_id (0) ->
   #weapon{
      id = 0,
      name = <<"None">>,
      range_type = melee,
      range_mod = short,
      damage_type = blunt,
      damage_mod = light,
      coef = 1.0
   };
from_id (1) ->
   #weapon{
      id = 1,
      name = <<"Dagger">>,
      range_type = melee,
      range_mod = short,
      damage_type = slash,
      damage_mod = light,
      coef = 1.0
   };
from_id (2) ->
   #weapon{
      id = 2,
      name = <<"Sword">>,
      range_type = melee,
      range_mod = short,
      damage_type = slash,
      damage_mod = heavy,
      coef = 1.0
   };
from_id (3) ->
   #weapon{
      id = 3,
      name = <<"Claymore">>,
      range_type = melee,
      range_mod = long,
      damage_type = slash,
      damage_mod = light,
      coef = 1.0
   };
from_id (4) ->
   #weapon{
      id = 4,
      name = <<"Bardiche">>,
      range_type = melee,
      range_mod = long,
      damage_type = slash,
      damage_mod = heavy,
      coef = 1.0
   };
from_id (5) ->
   #weapon{
      id = 5,
      name = <<"Stiletto">>,
      range_type = melee,
      range_mod = short,
      damage_type = pierce,
      damage_mod = light,
      coef = 1.0
   };
from_id (6) ->
   #weapon{
      id = 6,
      name = <<"Pickaxe">>,
      range_type = melee,
      range_mod = short,
      damage_type = pierce,
      damage_mod = heavy,
      coef = 1.0
   };
from_id (7) ->
   #weapon{
      id = 7,
      name = <<"Rapier">>,
      range_type = melee,
      range_mod = long,
      damage_type = pierce,
      damage_mod = light,
      coef = 1.0
   };
from_id (8) ->
   #weapon{
      id = 8,
      name = <<"Pike">>,
      range_type = melee,
      range_mod = long,
      damage_type = pierce,
      damage_mod = heavy,
      coef = 1.0
   };
from_id (9) ->
   #weapon{
      id = 9,
      name = <<"Club">>,
      range_type = melee,
      range_mod = short,
      damage_type = blunt,
      damage_mod = light,
      coef = 1.0
   };
from_id (10) ->
   #weapon{
      id = 10,
      name = <<"Mace">>,
      range_type = melee,
      range_mod = short,
      damage_type = blunt,
      damage_mod = heavy,
      coef = 1.0
   };
from_id (11) ->
   #weapon{
      id = 11,
      name = <<"Staff">>,
      range_type = melee,
      range_mod = long,
      damage_type = blunt,
      damage_mod = light,
      coef = 1.0
   };
from_id (12) ->
   #weapon{
      id = 12,
      name = <<"War Hammer">>,
      range_type = melee,
      range_mod = long,
      damage_type = blunt,
      damage_mod = heavy,
      coef = 1.0
   };
from_id (13) ->
   #weapon{
      id = 13,
      name = <<"Short Bow (Broadhead)">>,
      range_type = ranged,
      range_mod = short,
      damage_type = slash,
      damage_mod = light,
      coef = 1.0
   };
from_id (14) ->
   #weapon{
      id = 14,
      name = <<"Short Bow (Blunt)">>,
      range_type = ranged,
      range_mod = short,
      damage_type = blunt,
      damage_mod = light,
      coef = 1.0
   };
from_id (15) ->
   #weapon{
      id = 15,
      name = <<"Short Bow (Bodkin Point)">>,
      range_type = ranged,
      range_mod = short,
      damage_type = pierce,
      damage_mod = light,
      coef = 1.0
   };
from_id (16) ->
   #weapon{
      id = 16,
      name = <<"Long Bow (Broadhead)">>,
      range_type = ranged,
      range_mod = long,
      damage_type = slash,
      damage_mod = light,
      coef = 1.0
   };
from_id (17) ->
   #weapon{
      id = 17,
      name = <<"Long Bow (Blunt)">>,
      range_type = ranged,
      range_mod = long,
      damage_type = blunt,
      damage_mod = light,
      coef = 1.0
   };
from_id (18) ->
   #weapon{
      id = 18,
      name = <<"Long Bow (Bodkin Point)">>,
      range_type = ranged,
      range_mod = long,
      damage_type = pierce,
      damage_mod = light,
      coef = 1.0
   };
from_id (19) ->
   #weapon{
      id = 19,
      name = <<"Crossbow (Broadhead)">>,
      range_type = ranged,
      range_mod = short,
      damage_type = slash,
      damage_mod = heavy,
      coef = 1.0
   };
from_id (20) ->
   #weapon{
      id = 20,
      name = <<"Crossbow (Blunt)">>,
      range_type = ranged,
      range_mod = short,
      damage_type = blunt,
      damage_mod = heavy,
      coef = 1.0
   };
from_id (21) ->
   #weapon{
      id = 21,
      name = <<"Crossbow (Bodkin Point)">>,
      range_type = ranged,
      range_mod = short,
      damage_type = pierce,
      damage_mod = heavy,
      coef = 1.0
   };
from_id (22) ->
   #weapon{
      id = 22,
      name = <<"Arbalest (Broadhead)">>,
      range_type = ranged,
      range_mod = long,
      damage_type = slash,
      damage_mod = heavy,
      coef = 1.0
   };
from_id (23) ->
   #weapon{
      id = 23,
      name = <<"Arbalest (Blunt)">>,
      range_type = ranged,
      range_mod = long,
      damage_type = blunt,
      damage_mod = heavy,
      coef = 1.0
   };
from_id (24) ->
   #weapon{
      id = 24,
      name = <<"Arbalest (Bodkin Point)">>,
      range_type = ranged,
      range_mod = long,
      damage_type = pierce,
      damage_mod = heavy,
      coef = 1.0
   }.

-spec random_id () -> id().
random_id () -> sh_roll:between(0, 24).

-spec apply_to_attributes
   (
      type(),
      sh_attributes:type()
   )
   -> sh_attributes:type().
apply_to_attributes (Weapon, Attributes) ->
   Dexterity = sh_attributes:get_dexterity(Attributes),
   Speed = sh_attributes:get_speed(Attributes),
   RangeModifier = Weapon#weapon.range_mod,
   DamageModifier = Weapon#weapon.damage_mod,

   Impact = (20.0 * Weapon#weapon.coef),
   FullImpact = sh_math_util:ceil(Impact),
   QuarterImpact = sh_math_util:ceil(Impact / 4.0),

   ResultingDexterity =
      case RangeModifier of
         long -> (Dexterity - FullImpact);
         short -> (Dexterity - QuarterImpact)
      end,
   ResultingSpeed =
      case DamageModifier of
         heavy -> (Speed - FullImpact);
         light -> (Speed - QuarterImpact)
      end,

   S0Attributes = sh_attributes:set_speed(ResultingSpeed, Attributes),
   S1Attributes = sh_attributes:set_dexterity(ResultingDexterity, S0Attributes),

   S1Attributes.