# Xpose 4
# An R-based population pharmacokinetic/
# pharmacodynamic model building aid for NONMEM.
# Copyright (C) 1998-2004 E. Niclas Jonsson and Mats Karlsson.
# Copyright (C) 2005-2008 Andrew C. Hooker, Justin J. Wilkins, 
# Mats O. Karlsson and E. Niclas Jonsson.
# Copyright (C) 2009-2010 Andrew C. Hooker, Mats O. Karlsson and 
# E. Niclas Jonsson.

# This file is a part of Xpose 4.
# Xpose 4 is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public License
# as published by the Free Software Foundation, either version 3
# of the License, or (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Lesser General Public License for more details.

# You should have received a copy of the GNU Lesser General Public License
# along with this program.  A copy can be cound in the R installation
# directory under \share\licenses. If not, see http://www.gnu.org/licenses/.


#' Classic menu system for Xpose 4
#' 
#' @return NULL
#' @author Andrew Hooker
#' @keywords methods
#' @examples
#' 
#' \dontrun{
#' xpose4()
#' }
#' 
#' @export
#' @family classic functions 
#' @importFrom utils menu

xpose4 <- function() {
  
  ## check that classes are present
  # if (length(findClass("xpose.data")) < 1) {
  #   createXposeClasses()
  # }
  if (!isClass("xpose.data") || !isClass("xpose.prefs")) {
    createXposeClasses()
  }


  ##
  ## THIS messes up menu system!  Leave it out!
  ##
  ## Set error handling options such that it always return to the main
  ## menu. This may not necessarily be the best and a more elaborate
  ## error handling may be needed. See help for 'stop', 'try' and
  ## 'invokeRestart'.
  ##oldopts <- options(error=main.menu)
  ##on.exit(options(oldopts))
          
  cat("
              Welcome to Xpose!

       Xpose is a population analysis model
       building aid for NONMEM developed by:

       Andrew C. Hooker, Justin J. Wilkins,
       Mats O. Karlsson and E. Niclas Jonsson

       Pharmacometrics research group, 
       Department of Pharmaceutical Biosciences,
       Uppsala University, Sweden.
		                        
Version: Xpose ")
  cat(packageDescription("xpose4",fields=c("Version")),".","\n\n",sep="")
  cat(packageDescription("xpose4",fields=c("URL")),"\n\n")
  cat("Please report bugs at",  packageDescription("xpose4",fields=c("BugReports")),"\n\n")
  cat("Xpose, Copyright (C)", packageDescription("xpose4",fields=c("Copyright")),"\n\n")
cat("Xpose is free software and comes with ABSOLUTELY NO WARRANTY.
Xpose is made available under the terms of the GNU Lesser General
Public License (LGPL), version 3 or later. You are welcome to redistribute
it under the conditions described therein.  http://www.gnu.org/licenses/

")
  
  ## Get the data
  change.xp.obj()

  ## Start the menus
  main.menu()
  
  ##return()
}