#==============================================================================
# Storage Boxes Addon: Item Thefts
#   by IMP1
#------------------------------------------------------------------------------
# THIS SCRIPT REQUIRES THE 'STORAGE BOXES' SCRIPT BY IMP1
#
# You can set a box's last accessed time to the current time by having the 
# following in an event's script command:
#
#   $game_boxes.touch(3)
# This will reset the last accessed time of box 3 to the current time.
#
# To stop an item from being stolen, add <not stealable> into its notebox.
#------------------------------------------------------------------------------
#   Compatability:
#
# Aliased Methods:
#   IMP1_Game_Boxes.initialize
#   Scene_ItemStorage.start
#   Scene_ItemStorage.terminate
#
# New Methods/Fields:
#   Game_BaseItem.maximum_price
#   IMP1_Game_Boxes.touch
#   Scene_ItemStorage.process_past_thefts
#   Scene_ItemStorage.calculate_item_theft
#   Scene_ItemStorage.calculate_box_theft
#   Scene_ItemStorage.calculate_theft_probability
#
# Overwritten Methods:
#   none.
#
#------------------------------------------------------------------------------
#   Version History:
# v1.2 [2015/07/01] : Updated to use refactored base code.
# v1.1 [2014/11/18] : Added option of having boxes only stealable after the 
#                     first time they're accessed.
# v1.0 [2014/11/16] : Initial release.
#==============================================================================

module IMP1_Storage_Boxes
#------------------------------------------------------------------------------
# CONFIGURATION BEGIN:
#------------------------------------------------------------------------------
  
  # This is the minimum amount of time (in seconds) that have to have passed
  # for there to be any chance of an item being stolen.
  MINIMUM_THEFT_TIME = 10

  # This is the default probability that items will be stolen from this box.
  # Setting it to 0 will mean items cannot be stolen, and 1 will mean the box 
  # offers no protection against theft.
  DEFAULT_BOX_PROBABILITY = 0.5
  
  # You can set a box to have a probability other than the default.
  BOX_THEFT_PROBABILITIES = { # Do not remove.
  
    # The first box will have a probability of 0.8
    0 => 0.8,
    
    # The third will be very safe because of its low value.
    2 => 0.1
  
  } # Do not remove.
  
  DEFAULT_ITEM_THEFT = lambda { |gold_value, max_gold_value, key_item|
    # This is the default probability that an item will be stolen.
    # You can use the following variables:
    #   gold_value     : the price of the item (in the database).
    #   max_gold_value : the maximum price of all items.
    #   key_item       : this is 1 if the item is a key item and 0 if not.
    
    return (gold_value / max_gold_value) ** 0.5
    
  } # Do not remove.
  
  # If this is true then key items cannot be stolen.
  KEY_ITEMS_UNSTEALABLE = true
  
  # This is true, then boxes can only have items stolen from them after they
  # have been accessed for the first time (this will include the .touch 
  # function).
  ONLY_STEALABLE_AFTER_FIRST_VISIT = false
  
#------------------------------------------------------------------------------
# CONFIGURATION END.
#------------------------------------------------------------------------------
end

#==============================================================================
# Game_BaseItem
#==============================================================================
class Game_BaseItem
  # A new variable to hold the maximum price of any item.
  @@imp_max_price = nil
  #--------------------------------------------------------------------------
  # Set the time last accessed for all the boxes to the time now.
  #--------------------------------------------------------------------------
  def self.maximum_price
    if @@imp_max_price.nil?
      max = 0
      $data_items.each { |i| max = i.price if i && i.price && i.price > max }
      $data_weapons.each { |i| max = i.price if i && i.price && i.price > max }
      $data_armors.each { |i| max = i.price if i && i.price && i.price > max }
      @@imp_max_price = max
    end
    return @@imp_max_price
  end
  
end # Game_BaseItem

#==============================================================================
# Game_Boxes
#==============================================================================
class IMP1_Game_Boxes
  # The array of last accessed times of the boxes.
  attr_accessor :last_accessed
  #--------------------------------------------------------------------------
  # Set the time last accessed for all the boxes to the time now.
  #--------------------------------------------------------------------------
  alias :sans_steal_initialize :initialize unless $@
  def initialize
    sans_steal_initialize
    time = nil
    if ONLY_STEALABLE_AFTER_FIRST_VISIT
      time = Graphics.frame_count.to_f / Graphics.frame_rate
    end
    @last_accessed = Array.new(BOXES.size, time)
  end
  #--------------------------------------------------------------------------
  # Set the time last accessed for a box to the time now.
  #--------------------------------------------------------------------------
  def touch(box_id)
    @last_accessed[box_id] = Graphics.frame_count.to_f / Graphics.frame_rate
  end
  
end # IMP1_Game_Boxes

#==============================================================================
# Scene_ItemStorage
#==============================================================================
class Scene_ItemStorage
  #--------------------------------------------------------------------------
  # Before starting, it performs any thefts.
  #--------------------------------------------------------------------------
  alias :sans_steal_start :start unless $@
  def start
    process_past_thefts
    sans_steal_start
  end
  #--------------------------------------------------------------------------
  # Calculates thefts to be performed and executes them.
  #--------------------------------------------------------------------------
  def process_past_thefts
    last_access = $game_boxes.last_accessed[@box_id]
    return if last_access == nil
    time_now = Graphics.frame_count.to_f / Graphics.frame_rate
    t = time_now - last_access
    b = calculate_box_theft(@box_id)
    $game_boxes.box(@box_id).each do |item, num|
      k = calculate_item_theft(item)
      thefts = 0
      num.times do
        stolen = rand() < calculate_theft_probability(t, k, b)
        thefts += 1 if stolen
      end
      $game_boxes.remove_item(item, thefts, @box_id)
    end
  end
  #--------------------------------------------------------------------------
  # Creates the necessary parameters, and calls the function to calculate
  # the item's theft probability.
  #--------------------------------------------------------------------------
  def evaluate_item_formula(item)
    value = item.price.to_f
    max_value = Game_BaseItem.maximum_price
    key_item = item.is_a?(RPG::Item) && item.key_item? ? 1 : 0
    args = [value, max_value, key_item]
    result = IMP1_Storage_Boxes::DEFAULT_ITEM_THEFT.call(*args)
    return [[0, result].max, 1].min
  end
  #--------------------------------------------------------------------------
  # Returns the liklihood that this item will be stolen.
  #--------------------------------------------------------------------------
  def calculate_item_theft(item)
    if item.note.include?("<not stealable>") || 
          (item.is_a?(RPG::Item) && item.key_item? && 
          IMP1_Storage_Boxes::KEY_ITEMS_UNSTEALABLE)
      return 0
    elsif item.note.include?("<theft probability:")
      return item.note.scan(/<theft probability: (.+)>/).flatten[0].to_f
    else
      return evaluate_item_formula(item)
    end
  end
  #--------------------------------------------------------------------------
  # Returns the liklihood that an item will be stolen from this box.
  #--------------------------------------------------------------------------
  def calculate_box_theft(box)
    if IMP1_Storage_Boxes::BOX_THEFT_PROBABILITIES.keys.include?(box)
      return IMP1_Storage_Boxes::BOX_THEFT_PROBABILITIES[box]
    else
      return IMP1_Storage_Boxes::DEFAULT_BOX_PROBABILITY
    end
  end
  #--------------------------------------------------------------------------
  # Returns the liklihood that this item will be stolen from this box, given
  # that this amount of time has passed.
  #--------------------------------------------------------------------------
  def calculate_theft_probability(time, item, box)
    return 0 if time < IMP1_Storage_Boxes::MINIMUM_THEFT_TIME
    time -= IMP1_Storage_Boxes::MINIMUM_THEFT_TIME
    return box * item * (time) / (time + 1)
  end
  #--------------------------------------------------------------------------
  # Sets the last accessed time to when the box is closed.
  #--------------------------------------------------------------------------
  alias :sans_steal_terminate :terminate unless $@
  def terminate
    time_now = Graphics.frame_count.to_f / Graphics.frame_rate
    $game_boxes.last_accessed[@box_id] = time_now
    sans_steal_terminate
  end
  
end # Scene_ItemStorage