indexing
	description: "[
					This abstract class represents objects that are actions.
					See SHOW_SCNENE, SHOW_CLOSEUP, HIDE_CLOSEUP, PICKUP, REMOVE
					and CHANGE_SETTING

					This class is part of the XAE Extended Adventure Engine Project.
				  ]"

	author: "Adrian Rabenseifner, radrian@student.ethz.ch"
	date: "$Date$"
	revision: "$Revision$"

deferred class
	ACTION
inherit
	CONDITIONED

feature -- Access

	context_item: ITEM

	-- only used by engine
	perform(e: EVENT; g: GAME) is
			-- used by engine to perform action on a GAME object
		deferred
		end

	performable(context: CONTEXT): BOOLEAN is
			-- check performability
		local
			item_check: boolean
			c: BOOLEAN
		do
			-- action is performable if
			--		> conditions hold
			--		> context_item is corect
			item_check := ((context_item = context.context_item) or (context_item = void))
			--print ("   item check: " + item_check.out + "%N")
			c := check_conditions(context)
			--print ("   conditions: " + c.out + "%N")
			Result := c and item_check

			-- debug output
			-- io.put_string("performability check: ")
			-- io.put_boolean(Result)
			-- io.put_new_line
		end

	set_context_item(item: ITEM) is
			-- set context item
		do
			context_item := item
		end

end -- class ACTION