#==============================================================================
# ** Cache
#------------------------------------------------------------------------------
#  This module loads each of graphics, creates a Bitmap object, and retains it.
# To speed up load times and conserve memory, this module holds the created
# Bitmap object in the internal hash, allowing the program to return
# preexisting objects when the same bitmap is requested again.
#==============================================================================

module Cache
  #--------------------------------------------------------------------------
  # * Get Animation Graphic
  #    filename : Filename
  #    hue      : Hue change value
  #--------------------------------------------------------------------------
  def self.animation(filename, hue)
    load_bitmap("Graphics/Animations/", filename, hue)
  end
  #--------------------------------------------------------------------------
  # * Get Battler Graphic
  #    filename : Filename
  #    hue      : Hue change value
  #--------------------------------------------------------------------------
  def self.battler(filename, hue)
    load_bitmap("Graphics/Battlers/", filename, hue)
  end
  #--------------------------------------------------------------------------
  # * Get Character Graphic
  #    filename : Filename
  #--------------------------------------------------------------------------
  def self.character(filename)
    load_bitmap("Graphics/Characters/", filename)
  end
  #--------------------------------------------------------------------------
  # * Get Face Graphic
  #    filename : Filename
  #--------------------------------------------------------------------------
  def self.face(filename)
    load_bitmap("Graphics/Faces/", filename)
  end
  #--------------------------------------------------------------------------
  # * Get Parallax Background Graphic
  #    filename : Filename
  #--------------------------------------------------------------------------
  def self.parallax(filename)
    load_bitmap("Graphics/Parallaxes/", filename)
  end
  #--------------------------------------------------------------------------
  # * Get Picture Graphic
  #    filename : Filename
  #--------------------------------------------------------------------------
  def self.picture(filename)
    load_bitmap("Graphics/Pictures/", filename)
  end
  #--------------------------------------------------------------------------
  # * Get System Graphic
  #    filename : Filename
  #--------------------------------------------------------------------------
  def self.system(filename)
    load_bitmap("Graphics/System/", filename)
  end
  #--------------------------------------------------------------------------
  # * Clear Cache
  #--------------------------------------------------------------------------
  def self.clear
    @cache = {} if @cache == nil
    @cache.clear
    GC.start
  end
  #--------------------------------------------------------------------------
  # * Load Bitmap
  #--------------------------------------------------------------------------
  def self.load_bitmap(folder_name, filename, hue = 0)
    @cache = {} if @cache == nil
    path = folder_name + filename
    if not @cache.include?(path) or @cache[path].disposed?
      if filename.empty?
        @cache[path] = Bitmap.new(32, 32)
      else
        @cache[path] = Bitmap.new(path)
      end
    end
    if hue == 0
      return @cache[path]
    else
      key = [path, hue]
      if not @cache.include?(key) or @cache[key].disposed?
        @cache[key] = @cache[path].clone
        @cache[key].hue_change(hue)
      end
      return @cache[key]
    end
  end
end