[RGSS3] L'James Skill Traits

#==============================================================================
#
#
#                           L'James Skill Traits
#
#
# Requires L'James Notetag System
#==============================================================================
#                                Description
#==============================================================================
# Script allows to assign special traits to skills and items and then choose
# behaviour in reaction to them, namely:
#
# * Set damage rate recieved from skills/items with specified trait
# * Set damage rate dealt by skills/items with specified trait
# * Allow states to be removed in reaction to skills/items with specified
#   traits, like FFX Nul-spells
# * Restrict usage of skills/items with specified traits
#
#==============================================================================
#                                Instruction
#==============================================================================
# Insert this script between L'J Notetag System and Main
# Set list of traits
module LJ
  module SKILL_TRAITS
    TRAITS = [
      :physical,
      :magical,
      :fire,
      :ice,
      :lightning,
      :heal,
    ]
  end
end
# Use notetags to change game behaviour
#
# Note:
# some tags have multiple versions that can be written like
#     <tag arg1, arg2, arg3>
# or
#     <tag>
#       arg1
#       arg2
#       arg3
#     </tag>
#
#------------------------------------------------------------------------------
#                         Skill and Item notetags
#------------------------------------------------------------------------------
# These notetags go in the skill or item notebox in the database.
#
# * <<x>> assigns trait x to skill/item. E.g. <<fire>>
#
# * <take x> assigns trait x to skill/item but only if user of this skill/item
#     has feature <give x>. Also: <take x1, x2...>
#
# * <<take all>> same as <take x> but applied for all traits
#
#------------------------------------------------------------------------------
#                             State notetags
#------------------------------------------------------------------------------
# This notetag go in the state notebox in the database.
#
# * <removed by x> - state with this tag will be removed when skill/item with
#     trait x is applied to character with this state. Also <removed by x1, x2>
# * <added by x> - state with this tag will be added when skill/item with
#     trait x is applied to character with this state. Also <added by x1, x2>
#------------------------------------------------------------------------------
#                             Feature notetags
#------------------------------------------------------------------------------
# These notetag go in the actor, class, equipment, enemy or state notebox in
# the database. The behave like features of RPG Maker VXA
#
# * <give x> - assigns trait x to skills/items which take trait x.

# * <power x y%> - battler with this tag will deal y% damage when using
#     skills/items with trait x. y may be negative. Also <power x1 y1%, x2 y2%>
#
# * <damage x y%> - battler with this tag will receive y% damage from
#     skills/items with trait x. y may be negative. Also <damage x1 y1%, x2 y2%>
#
# * <ignore x> - battler with this tag will not be affected by skills/items
#     with trait x. Different from <damage x 0%> in that battler also ignores
#     state modifications, not only damage
#
# * <seal x> - battler can't use skills/items with trait x
#==============================================================================
#                                Terms of use
#==============================================================================
# Free to use in commercial and non-commercial projects as long as you give
# credit to L'James
#==============================================================================
#                             Notetag editing
#==============================================================================
# Here you can rename notetags if you prefer other names or these names
# are used in other scripts
module LJ
  module SKILL_TRAITS

    # Skills:
    # Parameter that takes selected given traits
    TAKE = :take
    # Parameter that takes all possible given traits
    TAKE_ALL = :take_all


    # States:
    # List of traits that remove this state
    REMOVED_BY = :removed_by

    # List of traits that add this state
    ADDED_BY = :added_by


    # Features:
    # List of traits that will be applied on skills/items with TAKE
    GIVE = :give

    # Damage multiplier for attacker
    POWER = :power

    # Damage multiplier for defender
    DAMAGE = :damage

    # List of traits that will make skills/items have no effect
    IGNORE = :ignore

    # List of traits that will make skills/items unusable
    SEAL = :seal

  end
end
module LJ
  module SKILL_TRAITS
    LJ::NOTETAGS.extension do
      # Here you can specify extension styling if you know how


#==============================================================================
#                  Don't touch unless you really want it
#==============================================================================

      declare_usableitem do
        TRAITS.each do |t|
          register t, trait
        end
        register TAKE, array(:sym).set_limit(*TRAITS)
        register TAKE_ALL, trait
      end

      declare_state do
        register REMOVED_BY, array(:sym).set_limit(*TRAITS)
        register ADDED_BY, array(:sym).set_limit(*TRAITS)
      end

      declare_features do
        register GIVE, array(:sym).set_limit(*TRAITS)
        register SEAL, array(:sym).set_limit(*TRAITS)
        register IGNORE, array(:sym).set_limit(*TRAITS)
        register POWER, hash(:percent).set_key_limit(*TRAITS)
        register DAMAGE, hash(:percent).set_key_limit(*TRAITS)
      end
    end
  end
end

class RPG::UsableItem::Damage
  attr_writer :multiplier

  alias eval_ljskilltraits eval
  def eval(a,b,v)
    @multiplier ||= 1
    res = @multiplier*eval_ljskilltraits(a,b,v)
    @multiplier = 1
    res
  end
end

class RPG::UsableItem < RPG::BaseItem
  def get_all_skill_traits(user)
    res = LJ::SKILL_TRAITS::TRAITS.select {|tr| get_param(tr)}
    if get_param(LJ::SKILL_TRAITS::TAKE_ALL)
      res += user.get_feature(LJ::SKILL_TRAITS::GIVE)
    else
      res += user.get_feature(LJ::SKILL_TRAITS::GIVE) &
        get_param(LJ::SKILL_TRAITS::TAKE)
    end
    res
  end
end

class Game_Battler < Game_BattlerBase

  alias make_damage_value_ljskilltraits make_damage_value
  def make_damage_value(user, item)
    item.damage.multiplier = item.get_all_skill_traits(user).inject(1) do
      |acc, tr|
      acc * user.get_feature(LJ::SKILL_TRAITS::POWER)[tr]
    end
    make_damage_value_ljskilltraits(user, item)
  end

  alias item_element_rate_ljskilltraits item_element_rate
  def item_element_rate(user, item)
    res = item_element_rate_ljskilltraits(user,item) *
      item.get_all_skill_traits(user).inject(1) do
        |acc, tr|
        acc * get_feature(LJ::SKILL_TRAITS::DAMAGE)[tr]
      end
  end

  alias item_test_ljskilltraits item_test
  def item_test(user, item)
    return false unless (item.get_all_skill_traits(user) &
      get_feature(LJ::SKILL_TRAITS::IGNORE)).empty?
    item_test_ljskilltraits(user, item)
  end

  alias item_apply_ljskilltraits item_apply
  def item_apply(user, item)
    item_apply_ljskilltraits(user, item)
    if @result.hit?
      traits = item.get_all_skill_traits(user)
      states.each do
        |state|
        remove_state(state.id) unless
          (state.get_param(LJ::SKILL_TRAITS::REMOVED_BY) & traits).empty?
      end
      $data_states.each do |state|
        add_state(state.id) unless state.nil? ||
          (state.get_param(LJ::SKILL_TRAITS::ADDED_BY) & traits).empty?

      end
    end
  end

  #overload
  def usable?(item)
    return false if item.is_a?(RPG::UsableItem) &&
    !(item.get_all_skill_traits(self) &
      get_feature(LJ::SKILL_TRAITS::SEAL)).empty?
    super(item)
  end

end