class Element
	include MicroChunkUser
	
	Ruleset_CUSX_base = $ruleset_CUSX_base
	Ruleset_GRPX = $ruleset_GRPX
	mcAccessorsFromRuleset(Ruleset_CUSX_base)
	mcAccessorsFromRuleset(Ruleset_GRPX)
	
	# TODO merge ruleset_GRPX and ElementGroupInfo with Element properly

	# IMPORTANT TODO the attribute list of elements in group element should be "gelement"
	# instead of "element"
	
	def tokenName
		# element token used in config files
		EL.token_name(@id)
	end
	def className
		# element class used in config files
		EL.class_name(@id)
	end
	def editorDescription(@id)
		# pre-defined description for level editor
		EL.editor_description(@id)
	end
	
#   char *custom_description;     /* alternative description from config file */
# 
#   /* ---------- graphic and sound definitions ---------- */
# 
#   int graphic[NUM_ACTIONS];     /* default graphics for several actions */
#   int direction_graphic[NUM_ACTIONS][NUM_DIRECTIONS_FULL];
#                                 /* special graphics for left/right/up/down */
# 
#   int crumbled[NUM_ACTIONS];    /* crumbled graphics for several actions */
#   int direction_crumbled[NUM_ACTIONS][NUM_DIRECTIONS_FULL];
#                                 /* crumbled graphics for left/right/up/down */
# 
#   int special_graphic[NUM_SPECIAL_GFX_ARGS];
#                                 /* special graphics for certain screens */
# 
#   int sound[NUM_ACTIONS];       /* default sounds for several actions */
# 
#   /* ---------- special element property values ---------- */
# 
#   unsigned long properties[NUM_EP_BITFIELDS];   /* element base properties */
# 
#   struct ElementChangeInfo *change_page; /* actual list of change pages */
#   struct ElementChangeInfo *change;      /* pointer to current change page */
# 
#   int num_change_pages;         /* actual number of change pages */
#   int current_change_page;      /* currently edited change page */
# 
#   struct ElementGroupInfo *group;       /* pointer to element group info */
# 
#   /* ---------- internal values used in level editor ---------- */
# 
#   int access_type;              /* walkable or passable */
#   int access_layer;             /* accessible over/inside/under */
#   int access_protected;         /* protection against deadly elements */
#   int walk_to_action;           /* diggable/collectible/pushable */
#   int smash_targets;            /* can smash player/enemies/everything */
#   int deadliness;               /* deadly when running/colliding/touching */
# 
#   boolean can_explode_by_fire;  /* element explodes by fire */
#   boolean can_explode_smashed;  /* element explodes when smashed */
#   boolean can_explode_impact;   /* element explodes on impact */
# 
#   boolean modified_settings;    /* set for all modified custom elements */
	
	def defaultDescription
		@custom_description ? @custom_description : @editor_description
	end
	
	def copyTo(ei_to)
		# TODO: probably use '@' instead of 'self' (where possible)
		mcCopyValuesTo(ei_to, Ruleset_CUSX_base)
	
		# ---------- reinitialize and copy change pages ----------
	
		ei_to.numChangePages = self.numChangePages
		ei_to.currentChangePage = self.currentChangePage
	
		ei_to.numChangePages.times do |i|
			ei_to.changePage[i] = self.changePage[i].dup
		end
	
		# mark this custom element as modified
		ei_to.modifiedSettings = true
		
		ei_to
	end
	
	def copy
		copyTo(Element.new)
	end
	
	# FIXME @deprecated! Use changePage.length instead.
	def numChangePages=(val)
		@changePage.length = val
	end
	def numChangePages
		@changePage.length
	end
	
	def currentChangePage
		@currentChangePage = 0 if !@currentChangePage
		@currentChangePage = @changePage.length-1 if @currentChangePage >= @changePage.length
		@currentChangePage
	end
	
	# TODO this should probably be renamed
	def change
		@changePage[currentChangePage]
	end
	
	def initialize(elementId)
		mcSetToDefaults(Ruleset_CUSX_base)
		mcSetToDefaults(Ruleset_GRPX)
		
		if IS_CUSTOM_ELEMENT(elementId) || IS_GROUP_ELEMENT(elementId) || IS_INTERNAL_ELEMENT(elementId)
			mcSetToDefaults(Ruleset_CUSX_base)
		end

		@changePage = Array.new
		@changePage.setDefault { ChangePage.new }
		@changePage.length = 1

		if IS_CUSTOM_ELEMENT(elementId) || IS_GROUP_ELEMENT(elementId) || IS_INTERNAL_ELEMENT(elementId)
			@description = defaultDescription
			@modified_settings = false
		end

		if IS_CUSTOM_ELEMENT(elementId) || IS_INTERNAL_ELEMENT(elementId)
			# internal values used in level editor
			# TODO: maybe these aren't needed? (And virtual attributes can be used instead?)

			@access_type = 0
			@access_layer = 0
			@access_protected = 0
			@walk_to_action = 0
			@smash_targets = 0
			@deadliness = 0

			@can_explode_by_fire = false
			@can_explode_smashed = false
			@can_explode_impact = false

			@current_change_page = 0
		end
	end
	
	#
	# 'content' is stored as TYPE_CONTENT_LIST (struct Content[] in C) in
	# ruleset_CUSX_base. That's because microchunks don't have a 'TYPE_CONTENT'.
	# In C, it didn't make any difference, because a pointer to array of structs
	# Content ('struct Content*') is the same as a pointer to one struct Content
	# ('struct Content*'). However, in Ruby it does make a difference. So I'm
	# using these helper functions. If the program tries to set content to array
	# of Contents, it uses only the first (and probably only) item from it, and
	# similarly if the program tries to get the array of contents, it returns an
	# array that contains only @content.
	#
	def mcGet_content(index)
		return @content if index
		return [@content]
	end
	def mcSet_content(val,index)
		@content = val if index
		@content = val[0] if !index
	end
	
	def defaultDescription
		@customDescription ? @customDescription : editorDescription
	end
end