[RGSS3] Geomancy skill

##
# Copyright (c) 2016 Zeriab
#
# This software is provided 'as-is', without any express or implied
# warranty. In no event will the authors be held liable for any damages
# arising from the use of this software.
#
# Permission is granted to anyone to use this software for any purpose,
# including commercial applications, and to alter it and redistribute it
# freely, subject to the following restrictions:
#
# 1. The origin of this software must not be misrepresented; you must not
#    claim that you wrote the original software. If you use this software
#    in a product, an acknowledgement in the product documentation would be
#    appreciated but is not required.
# 2. Altered source versions must be plainly marked as such, and must not be
#    misrepresented as being the original software.
# 3. This notice may not be removed or altered from any source distribution.
#
##
# Interpreter command
#
# Use in a script call to set current geomancy tag:
#   set_geomancy_tag(1)
#
# To disable geomancy use
#   set_geomancy_tag(0)
#
def set_geomancy_tag(tag)
  $game_player.geomancy_tag = tag
end

##
# Add geomancy tags to skills
#
class RPG::Skill < RPG::UsableItem
  attr_writer :geomancy_tags
  def geomancy_tags
    @geomancy_tags ||= []
    return @geomancy_tags
  end

  def add_tag(tag)
    self.geomancy_tags << tag
  end

  def geomancy?
    !geomancy_tags.empty?
  end
end

##
# Player has a specific geomancy tag
#
class Game_Player < Game_Character
  attr_accessor :geomancy_tag
  def geomancy?
    return geomancy_tag != nil && geomancy_tag > 0
  end

  ##
  # Clear geomancy tag upon transfer
  #
  alias_method :geomancy_clear_transfer_info, :clear_transfer_info
  def clear_transfer_info
    geomancy_clear_transfer_info
    self.geomancy_tag = 0
  end

end

##
# Geomancy skill check
#
class Game_BattlerBase
  alias_method :geomancy_skill_conditions_met?, :skill_conditions_met?
  def skill_conditions_met?(skill)
    enabled = geomancy_skill_conditions_met?(skill)
    # Geomancy conditions check
    if enabled && skill.geomancy? && $game_player.geomancy?
      enabled = skill.geomancy_tags.include?($game_player.geomancy_tag)
    end
    return enabled
  end
end

##
# Setup skill geomancy as post-processing part of loading the database
#
module DataManager
  class << self
    alias_method :geomancy_load_database, :load_database
    def load_database(*args)
      geomancy_load_database(*args)
      database_post_process
    end

    def database_post_process
      setup_geomancy
    end

    ##
    # User interface for adding geomancy tags
    #
    def add_geomancy_tag(hash)
      skill_id = hash[:skill_id]
      tag = hash[:tag]
      skill = $data_skills[skill_id]
      unless skill.nil? || tag.nil?
        skill.add_tag(tag)
      end
    end
  end
end

__END__
# Configuration section - I recommend putting this code in a different section of the script editor
module DataManager
  module_function
  def setup_geomancy
    # Specify geomancy tags here
    # Note: Tags using 0 will be ignored
    add_geomancy_tag(:skill_id => 80, :tag => 1)
    add_geomancy_tag(:skill_id => 81, :tag => 2)
  end
end