indexing
	description: "[
		Objects that query the current installation directory of the tour.
		]"
	legal: "See notice at end of class."
	status: "See notice at end of class."
	author: ""
	date: "$Date$"
	revision: "$Revision$"

class
	INSTALLATION_LOCATOR

inherit
	EIFFEL_LAYOUT
		export
			{NONE} all
		end

feature -- Access

	installation_location: STRING is
			-- Location of installation.
			-- `Void' if environment variables not correctly set.
		local
			file_location: STRING
			directory_name: DIRECTORY_NAME
		do
			directory_name := eiffel_layout.eiffel_installation_dir_name.twin
			directory_name.extend ("vision2_tour")
			if not valid_installation (directory_name.out) then
				directory_name := Void
			end
			if directory_name /= Void then
				Result := directory_name.out
			end
		end

feature {NONE} -- Implementation

	valid_installation (root_location: STRING): BOOLEAN is
			-- Ensure that the Environment variables if found, are correct.
			-- To do this, we sample a few of the files required by the system.
			-- If they are not available, then the installation is not
			-- considered to be valid.
		local
			filename: FILE_NAME
			directory: DIRECTORY
		do
			Result := True
			create filename.make_from_string (root_location)
			filename.extend ("bitmaps")
			filename.extend ("png")
			create directory.make (filename)
			if not directory.exists then
				Result := False
			end

			create filename.make_from_string (root_location)
			filename.extend ("flatshort")
			create directory.make (filename)
			if not directory.exists then
				Result := False
			end

			create filename.make_from_string (root_location)
			filename.extend ("templates")
			create directory.make (filename)
			if not directory.exists then
				Result := False
			end

			create filename.make_from_string (root_location)
			filename.extend ("tests")
			create directory.make (filename)
			if not directory.exists then
				Result := False
			end
		end

	image_extension: STRING is
			-- Extension type of image formats on current platform.
			-- either "png" or "ico"
		once
			Result := "png"
		ensure
			Result_valid: Result.is_equal ("png")
		end

indexing
	copyright:	"Copyright (c) 1984-2006, Eiffel Software and others"
	license:	"Eiffel Forum License v2 (see http://www.eiffel.com/licensing/forum.txt)"
	source: "[
			 Eiffel Software
			 356 Storke Road, Goleta, CA 93117 USA
			 Telephone 805-685-1006, Fax 805-685-6869
			 Website http://www.eiffel.com
			 Customer support http://support.eiffel.com
		]"


end -- class INSTALLATION_LOCATOR