#! /usr/local/bin/python2.7

"""
This program is the GUI incarnation of parmed.py.  It depends on the Tkinter
package, which is the Tcl/Tk interface with Python, as the GUI toolkit. This is
the most common GUI toolkit in Python (and is included in the stdlib).

All it really does is give users a point-and-click, guided tour through 
everything parmed can do
"""

import sys
from os.path import exists, split
from optparse import OptionParser
from ParmedTools.exceptions import ParmError
from chemistry.amber.readparm import AmberParm, ChamberParm, AmberFormat
from ParmedTools import ParmedActions
from ParmedTools import __version__
import Tkinter as tk
from ParmedTools.gui.guitools import ParmedApp
from ParmedTools.gui.guifiletools import file_chooser
from tkMessageBox import showerror
from ParmedTools.logos import Logo
from ParmedTools.ParmedActions import Action
from ParmedTools.parmlist import ParmList

debug = False

def excepthook(exception_type, exception_value, tb):
   """ Default exception handler """
   import traceback
   if debug: traceback.print_tb(tb)
   showerror('Fatal Error','%s: %s' % (exception_type.__name__,exception_value))
   sys.exit(1)

def main():
   """ The main function """
   global excepthook, debug
   # Launch the root window
   root = tk.Tk()
   root.resizable(True, True)

   # Replace the default excepthook with mine
   sys.excepthook = excepthook

   # See if we were provided a topology file on the command-line
   parser = OptionParser(usage = '%prog [<prmtop>]')
   parser.add_option('-d', '--debug', dest='debug', default=False, 
                     action='store_true', help='Show detailed tracebacks ' +
                     'when an error is detected.')
   opt, args = parser.parse_args()

   debug = opt.debug

   # If the user provided a CL argument, that is the prmtop_name. Otherwise,
   # open up a file choosing dialog box to get the input from the user
   if len(args) == 0:
      prmtop_name = file_chooser('Topology')
   elif len(args) == 1:
      prmtop_name = args[0]
   else:
      print >> sys.stderr, 'Unknown command-line options. Ignoring'
      prmtop_name = file_chooser('Topology')

   # If we chose no prmtop file, 
   if not prmtop_name: raise ParmError('No prmtop chosen!')

   # Load the amber prmtop and check for errors
   amber_prmtop = ParmList()
   parm = AmberFormat(prmtop_name)
   if 'CTITLE' in parm.flag_list:
      parm = parm.view(ChamberParm)
   else:
      parm = parm.view(AmberParm)
   amber_prmtop.add_parm(parm)

   # Make this overwritable -- the all of the file save boxes will ask the user
   # for verification before saving over an existing file. There's no need for
   # the AmberParm security layer.
   Action.overwrite = True

   fname = split(prmtop_name)[1]
   root.title('xParmED: Editing/viewing [%s] Choose an operation' % fname)

   # Make sure our topology file is valid
   if not amber_prmtop.parm.valid:
      raise ParmError('Bad (or non-existent) topology file [%s]' % prmtop_name)

   # Now build the action list on root
   app = ParmedApp(root, amber_prmtop)
   app.pack(fill=tk.BOTH, expand=1)
   root.mainloop()

   print 'Thank you for using xParmEd!\n%s' % Logo()

if __name__ == '__main__': main()