#!/usr/bin/env python

"""
    lttree_postprocess.py
    This is a stand-alone python script which checks the files created by
    lttree.py to insure that the standard instance-variables ($variables)
    have all been defined.  This script performs a task which is very similar
    to the task performed by lttree_check.py.  This script attempts to detect
    mistakes in the names of $atom, $bond, $angle, $dihedral, $improper, & $mol
    variables.

"""

import sys

try:
    from .lttree_styles import *
    from .ttree_lex import ExtractCatName
except (SystemError, ValueError):
    # not installed as a package
    from lttree_styles import *
    from ttree_lex import ExtractCatName

g_program_name = __file__.split('/')[-1]  # = 'lttree_postprocess.py'
g_version_str = '0.5.0'
g_date_str = '2016-12-21'

def main():
    atom_style = 'full'
    ttree_assignments_fname = 'ttree_assignments.txt'

    defined_mols = set([])
    defined_atoms = set([])
    defined_bonds = set([])
    defined_angles = set([])
    defined_dihedrals = set([])
    defined_impropers = set([])

    g_no_check_msg = \
        '(To override this error, run moltemplate using the \"-nocheck\" argument.)\n'

    if len(sys.argv) > 1:
        for i in range(0, len(sys.argv)):
            if ((sys.argv[i].lower() == '-atomstyle') or
                    (sys.argv[i].lower() == '-atom-style') or
                    (sys.argv[i].lower() == '-atom_style')):
                if i + 1 >= len(sys.argv):
                    raise InputError('Error(' + g_program_name + '): The ' + sys.argv[i] + ' flag should be followed by a LAMMPS\n'
                                     '       atom_style name (or single quoted string containing a space-separated\n'
                                     '       list of column names such as: atom-ID atom-type q x y z molecule-ID.)\n')

                atom_style = sys.argv[i + 1]
            elif ((sys.argv[i].lower() == '-ttreeassignments') or
                  (sys.argv[i].lower() == '-ttree-assignments') or
                  (sys.argv[i].lower() == '-ttree_assignments')):
                if i + 1 >= len(sys.argv):
                    raise InputError('Error(' + g_program_name + '): The ' + sys.argv[i] + ' flag should be followed by \n'
                                     '       a file containing the variable bindings created by ttree/moltemplate.\n')
                ttree_assignments_fname = sys.argv[i + 1]
            else:
                pass  # ignore other arguments (they are intended for lttree.py)


    atom_column_names = AtomStyle2ColNames(atom_style)
    i_atomid = 0
    i_molid = -1
    for i in range(0, len(atom_column_names)):
        if atom_column_names[i].lower() == 'atom-id':
            i_atomid = i
        elif atom_column_names[i].lower() == 'molecule-id':
            i_molid = i
    i_max_column = max(i_atomid, i_molid)


    # The following variables are defined in "lttree_styles.py"
    #data_atoms="Data Atoms"
    #data_masses="Data Masses"
    #data_velocities="Data Velocities"
    #data_bonds="Data Bonds"
    #data_angles="Data Angles"
    #data_dihedrals="Data Dihedrals"
    #data_impropers="Data Impropers"


    sys.stderr.write(g_program_name + ' v' +
                     g_version_str + ' ' + g_date_str + '\n')

    try:
        # ------------ defined_atoms ------------
        try:
            f = open(data_atoms + '.template', 'r')
        except:
            raise InputError('Error(' + g_program_name + '): Unable to open file\n' +
                             '\"' + data_atoms + '.template\"\n'
                             '       for reading.  (Do your files lack a \"' +
                             data_atoms + '\" section?)\n'
                             + g_no_check_msg + '\n')

        for line_orig in f:
            ic = line_orig.find('#')
            if ic != -1:
                line = line_orig[:ic]
            else:
                line = line_orig.rstrip('\n')

            tokens = line.strip().split()
            if len(tokens) == 0:
                pass
            elif len(tokens) <= i_max_column:
                raise InputError('Error(' + g_program_name + '): The following line from\n'
                                 '     "\"' + data_atoms + '.template\" has bad format:\n\n'
                                 + line_orig + '\n'
                                 '     This my probably an internal error. (Feel free to contact the developer.)\n'
                                 + g_no_check_msg + '\n')
            else:
                defined_atoms.add(tokens[i_atomid])
                if i_molid != -1:
                    defined_mols.add(tokens[i_molid])

        f.close()

        # ------------ defined_bonds ------------
        try:
            f = open(data_bonds + '.template', 'r')

            for line_orig in f:
                ic = line_orig.find('#')
                if ic != -1:
                    line = line_orig[:ic]
                else:
                    line = line_orig.rstrip('\n')

                tokens = line.strip().split()
                if len(tokens) == 0:
                    pass
                elif len(tokens) < 4:
                    raise InputError('Error(' + g_program_name + '): The following line from\n'
                                     '     "\"' + data_bonds + '.template\" has bad format:\n\n'
                                     + line_orig + '\n'
                                     '     This my probably an internal error. (Feel free to contact the developer.)\n'
                                     + g_no_check_msg + '\n')
                else:
                    defined_bonds.add(tokens[0])
            f.close()
        except:
            pass  # Defining bonds (stored in the data_bonds file) is optional

        # ------------ defined_angles ------------
        try:
            f = open(data_angles + '.template', 'r')
            for line_orig in f:
                ic = line_orig.find('#')
                if ic != -1:
                    line = line_orig[:ic]
                else:
                    line = line_orig.rstrip('\n')

                tokens = line.strip().split()
                if len(tokens) == 0:
                    pass
                elif len(tokens) < 5:
                    raise InputError('Error(' + g_program_name + '): The following line from\n'
                                     '     "\"' + data_angles + '.template\" has bad format:\n\n'
                                     + line_orig + '\n'
                                     '     This my probably an internal error. (Feel free to contact the developer.)\n'
                                     + g_no_check_msg + '\n')
                else:
                    defined_angles.add(tokens[0])
            f.close()
        except:
            pass  # Defining angles (stored in the data_angles file) is optional

        # ------------ defined_dihedrals ------------
        try:
            f = open(data_dihedrals + '.template', 'r')
            for line_orig in f:
                ic = line_orig.find('#')
                if ic != -1:
                    line = line_orig[:ic]
                else:
                    line = line_orig.rstrip('\n')

                tokens = line.strip().split()
                if len(tokens) == 0:
                    pass
                elif len(tokens) < 6:
                    raise InputError('Error(' + g_program_name + '): The following line from\n'
                                     '     "\"' + data_dihedrals + '.template\" has bad format:\n\n'
                                     + line_orig + '\n'
                                     '     This my probably an internal error. (Feel free to contact the developer.)\n'
                                     + g_no_check_msg + '\n')
                else:
                    defined_dihedrals.add(tokens[0])
            f.close()
        except:
            # Defining dihedrals (stored in the data_dihedrals file) is optional
            pass

        # ------------ defined_impropers ------------
        try:
            f = open(data_impropers + '.template', 'r')

            for line_orig in f:
                ic = line_orig.find('#')
                if ic != -1:
                    line = line_orig[:ic]
                else:
                    line = line_orig.rstrip('\n')

                tokens = line.strip().split()
                if len(tokens) == 0:
                    pass
                elif len(tokens) < 6:
                    raise InputError('Error(' + g_program_name + '): The following line from\n'
                                     '     "\"' + data_impropers + '.template\" has bad format:\n\n'
                                     + line_orig + '\n'
                                     '     This my probably an internal error. (Feel free to contact the developer.)\n'
                                     + g_no_check_msg + '\n')
                else:
                    defined_impropers.add(tokens[0])
            f.close()
        except:
            # Defining impropers (stored in the data_impropers file) is optional
            pass

        # ---- Check ttree_assignments to make sure variables are defined ----

        try:
            f = open(ttree_assignments_fname, 'r')
        except:
            raise InputError('Error(' + g_program_name + '): Unable to open file\n' +
                             '\"' + ttree_assignments_fname + '\"\n'
                             '       for reading.  (Do your files lack a \"' +
                             data_atoms + '\" section?)\n'
                             + g_no_check_msg + '\n')

        for line_orig in f:

            ic = line_orig.find('#')
            if ic != -1:
                line = line_orig[:ic]
                usage_location_str = 'near ' + line_orig[ic + 1:]
            else:
                line = line_orig.rstrip('\n')
                usage_location_str = ''

            tokens = line.strip().split()
            if len(tokens) == 0:
                pass
            if len(tokens) > 0:
                # This file contains a list of variables of the form:
                #
                # @/atom:MoleculeType1:C    1
                # @/atom:MoleculeType1:H    2
                # @/atom:MoleculeType2:N    3
                # $/atom:molecule1:N1    1
                # $/atom:molecule1:C1    2
                #   :
                # $/atom:molecule1141:CH    13578
                # $/atom:molecule1142:N3    13579
                #   :
                # We only care about instance variables (which use the '$' prefix)
                # Lines corresponding to static variables (which use the '@' prefix)
                # are ignored during this pass.
                i_prefix = tokens[0].find('$')
                if i_prefix != -1:
                    descr_str = tokens[0][i_prefix + 1:]
                    cat_name = ExtractCatName(descr_str)

                    if ((cat_name == 'atom') and
                            (tokens[0] not in defined_atoms)):
                        raise InputError('Error(' + g_program_name + '): ' + usage_location_str + '\n' +
                                         '      Reference to undefined $atom:\n\n'
                                         '            ' + tokens[0] + '     (<--full name)\n\n' +
                                         '      (If that atom belongs to a molecule (or other subunit), make sure that\n' +
                                         '       you specified the correct path which leads to it (using / and ..))\n\n' +
                                         g_no_check_msg)

                    elif ((cat_name == 'bond') and
                          (tokens[0] not in defined_bonds)):
                        raise InputError('Error(' + g_program_name + '): ' + usage_location_str + '\n' +
                                         '      Reference to undefined $bond:\n\n'
                                         '            ' + tokens[0] + '     (<--full name)\n\n' +
                                         '      (If that bond belongs to a molecule (or other subunit), make sure that\n' +
                                         '       you specified the correct path which leads to it (using / and ..))\n\n' +
                                         g_no_check_msg)

                    elif ((cat_name == 'angle') and
                          (tokens[0] not in defined_angles)):
                        raise InputError('Error(' + g_program_name + '): ' + usage_location_str + '\n' +
                                         '      Reference to undefined $angle:\n\n' +
                                         '            ' + tokens[0] + '     (<--full name)\n\n' +
                                         '      (If that angle belongs to a molecule (or other subunit), make sure that\n' +
                                         '       you specified the correct path which leads to it (using / and ..))\n\n' +
                                         g_no_check_msg)

                    elif ((cat_name == 'dihedral') and
                          (tokens[0] not in defined_dihedrals)):
                        raise InputError('Error(' + g_program_name + '): ' + usage_location_str + '\n\n' +
                                         '      Reference to undefined $dihedral:\n\n'
                                         '            ' + tokens[0] + '     (<--full name)\n\n' +
                                         '    (If that dihedral belongs to a molecule (or other subunit), make sure that\n' +
                                         '     you specified the correct path which leads to it (using / and ..))\n\n' +
                                         g_no_check_msg)

                    elif ((cat_name == 'improper') and
                          (tokens[0] not in defined_impropers)):
                        raise InputError('Error(' + g_program_name + '): ' + usage_location_str + '\n' +
                                         '      Reference to undefined $improper:\n\n'
                                         '            ' + tokens[0] + '     (<--full name)\n\n' +
                                         '    (If that improper belongs to a molecule (or other subunit), make sure that\n' +
                                         '     you specified the correct path which leads to it (using / and ..))\n\n' +
                                         g_no_check_msg)

                    # I used to generate an error when a users defines a $mol
                    # variable but does not associate any atoms with it (or if the
                    # user systematically deletes all the atoms in that molecule),
                    # but I stopped this practice.
                    # I don't think there is any real need to complain if some
                    # molecule id numbers are undefined.  LAMMPS does not care.
                    #
                    # elif ((cat_name == 'mol') and
                    #    (tokens[0] not in defined_mols)):
                    #    raise InputError('Error('+g_program_name+'): '+usage_location_str+'\n'+
                    #                     '      Reference to undefined $mol (molecule-ID) variable:\n\n'
                    #                     '            '+tokens[0]+'     (<--full name)\n\n'+
                    #                     '    (If that molecule is part of a larger molecule, then make sure that\n'+
                    #                     '     you specified the correct path which leads to it (using / and ..))\n\n'+
                    #                     g_no_check_msg)

        f.close()

        sys.stderr.write(g_program_name + ': -- No errors detected. --\n')
        exit(0)


    except (ValueError, InputError) as err:
        sys.stderr.write('\n' + str(err) + '\n')
        sys.exit(1)

    return

if __name__ == '__main__':
    main()
