ITEM DROPED BASED ON ANOTHER ITEM HOW?

module TRI
  module REGEX
    ITEM_REQ = /<item_req:[ ]*(.+?)>/i
  end
end

module DataManager
  class << self
    alias_method(:tri_load_database, :load_database)
  end
  def self.load_database
    tri_load_database
    load_prereq_notetags
  end
  
  def self.load_prereq_notetags
    for obj in $data_enemies
      next if obj.nil?
      obj.load_prereq_notetags
    end
    puts "Read: Item prerequisite notetags"
  end
end

class Game_Enemy < Game_Battler
  def get_prereq(index)
    if enemy.item_req[index]
      enemy.item_req[index]
    else
      0
    end
  end
  
  #--------------------------------------------------------------------------
  # * Create Array of Dropped Items
  #--------------------------------------------------------------------------
  def make_drop_items
    index = 0
    enemy.drop_items.inject([]) do |r, di|
      if di.kind > 0 && rand * di.denominator < drop_item_rate && (get_prereq(index) == 0 || $game_party.has_item?($data_items[get_prereq(index)]))
        index += 1
        r.push(item_object(di.kind, di.data_id))
      else
        index += 1
        r
      end
    end
  end
end

class RPG::Enemy < RPG::BaseItem
  attr_accessor :item_req
  
  def load_prereq_notetags
    @note.split(/[\r\n]+/).each do |line|
      case line
      when TRI::REGEX::ITEM_REQ
        @item_req = []
        @item_req |= $1.scan(/\d+/).collect { |id| id.to_i }
      end
    end
  end
end