# $Id$
##
##  This file is part of pyFormex 1.0.5  (Sat Feb 16 10:40:32 CET 2019)
##  pyFormex is a tool for generating, manipulating and transforming 3D
##  geometrical models by sequences of mathematical operations.
##  Home page: http://pyformex.org
##  Project page:  http://savannah.nongnu.org/projects/pyformex/
##  Copyright 2004-2018 (C) Benedict Verhegghe (benedict.verhegghe@ugent.be)
##  Distributed under the GNU General Public License version 3 or later.
##
##  This program is free software: you can redistribute it and/or modify
##  it under the terms of the GNU 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 General Public License for more details.
##
##  You should have received a copy of the GNU General Public License
##  along with this program.  If not, see http://www.gnu.org/licenses/.
##

"""
Interface with Abaqus/Calculix FE input files (.inp).


"""
from __future__ import absolute_import, division, print_function

#
# DEVS: Try to do this without importing from pyformex
#

import re
import numpy as np
from pyformex import utils
from pyformex.coords import concatenate

re_eltypeB = re.compile("^(?P<type>B)(?P<ndim>[23])(?P<degree>\d)?(?P<mod>(OS)?H*)$")
re_eltype = re.compile("^(?P<type>.*?)(?P<ndim>[23]D)?(?P<nplex>\d+)?(?P<mod>[HIMRSW]*)$")

#
# List of known Abaqus/Calculix element type
#
#

abq_elems = [
    'SPRINGA',
    'CONN3D2', 'CONN2D2',
    'FRAME3D', 'FRAME2D',
    'T2D2', 'T2D2H', 'T2D3', 'T2D3H',
    'T3D2', 'T3D2H', 'T3D3', 'T3D3H',
    'B21', 'B21H', 'B22', 'B22H', 'B23', 'B23H',
    'B31', 'B31H', 'B32', 'B32H', 'B33', 'B33H',
    'M3D3',
    'M3D4', 'M3D4R',
    'M3D6', 'M3D8',
    'M3D8R',
    'M3D9', 'M3D9R',
    'CPS3',
    'CPS4', 'CPS4I', 'CPS4R',
    'CPS6', 'CPS6M',
    'CPS8', 'CPS8R', 'CPS8M',
    'CPE3', 'CPE3H',
    'CPE4', 'CPE4H', 'CPE4I', 'CPE4IH', 'CPE4R', 'CPE4RH',
    'CPE6', 'CPE6H', 'CPE6M', 'CPE6MH',
    'CPE8', 'CPE8H', 'CPE8R', 'CPE8RH',
    'CPEG3', 'CPEG3H',
    'CPEG4', 'CPEG4H', 'CPEG4I', 'CPEG4IH', 'CPEG4R', 'CPEG4RH',
    'CPEG6', 'CPEG6H', 'CPEG6M', 'CPEG6MH',
    'CPEG8', 'CPEG8H', 'CPEG8R', 'CPEG8RH',
    'CAX6', 'CAX8', 'CAX8R',
    'S3', 'S3R', 'S3RS',
    'S4', 'S4R', 'S4RS', 'S4RSW', 'S4R5',
    'S8R', 'S8R5',
    'S9R5',
    'STRI3',
    'STRI65',
    'SC8R',
    'SFM3D3',
    'SFM3D4', 'SFM3D4R',
    'SFM3D6',
    'SFM3D8', 'SFM3D8R',
    'C3D4', 'C3D4H',
    'C3D6', 'C3D6H',
    'C3D8', 'C3D8I', 'C3D8H', 'C3D8R', 'C3D8RH', 'C3D10',
    'C3D10H', 'C3D10M', 'C3D10MH',
    'C3D15', 'C3D15H',
    'C3D20', 'C3D20H', 'C3D20R', 'C3D20RH',
    'R2D2', 'RB2D2', 'RB3D2', 'RAX2', 'R3D3', 'R3D4',
    ]


def abq_eltype(eltype):
    """Analyze an Abaqus element type and return eltype characteristics.

    Returns a dictionary with:

    - type: the element base type
    - ndim: the dimensionality of the element
    - nplex: the plexitude (number of nodes)
    - mod: a modifier string

    Currently, all these fields are returned as strings. We should probably
    change ndim and nplex to an int.
    """
    if eltype.startswith('B'):
        m = re_eltypeB.match(eltype)
    else:
        m = re_eltype.match(eltype)
    if m:
        d = m.groupdict()
        try:
            nplex = int(d['nplex'])
        except:
            if 'degree' in d:
                degree = int(m.group('degree'))
                if degree == 2:
                    nplex = 3
                else:
                    nplex = 2
            elif d['type'] == 'FRAME':
                nplex = 2
            elif d['type'] == 'SPRINGA':
                nplex = 1
            else:
                nplex = 0
        d['nplex'] = nplex
        if 'ndim' not in d or d['ndim'] is None:
            if d['type'][:2] in ['CP', 'CA'] :
                d['ndim'] = '2'
        if d['type'] in ['R'] and d['nplex']==4:
            d['ndim'] = '2'
        try:
            ndim = int(d['ndim'][0])
        except:
            ndim = 3
        d['ndim'] = ndim
        if 'mod' not in d or d['mod'] is None:
            d['mod'] = ''
        d['avail'] = 'A'   # Available in Abaqus
        d['pyf'] = pyf_eltype(d)
    else:
        d = {}
    return d


known_eltypes = {
    1: { 'point': [ 'SPRINGA', ] },
    2: { 'line2': [ 'CONN', 'FRAME', 'T', 'B', 'RB', 'RAX',] },
    3: { 'line3': [ 'B', ],
         'tri3':  [ 'M', 'CPS', 'CPE', 'CPEG', 'S', 'SFM', 'R', ] },
    4: { 'quad4': [ 'M', 'CPS', 'CPE', 'CPEG', 'S', 'SFM', 'R', ],
         'tet4':  [ 'C', ] },
    6: { '':  [ 'M', 'CPS', 'CPE', 'CPEG', 'SFM', ],
         'wedge6':[ 'C', ] },
    8: { 'quad8': [ 'M', 'CPS', 'CPE', 'CPEG', 'CAX', 'S', 'SFM', ],
         'hex8':  [ 'C', ] },
    9: { 'quad9': [ 'M', 'S' ] },
    10: { 'tet10': [ 'C', ] },
    15: { '': [ 'C', ] },
    20: { 'hex20': [ 'C', ] },
    }

pyf_eltypes = {
    1:  'point',
    2:  'line2',
    3:  { 2: 'line3', 3: 'tri3'   },
    4:  { 2: 'quad4', 3: 'tet4'   },
    6:  { 2: ''     , 3: 'wedge6' },
    8:  { 2: 'quad8', 3: 'hex8'   },
    9:  'quad9',
    10: 'tet10',
    15: '',
    20: 'hex20',
    }


def pyf_eltype(d):
    """Return the best matching pyFormex element type for an abq/ccx element

    d is an element groupdict obtained by scanning the element name.
    """
    eltype = pyf_eltypes.get(d['nplex'], '')
    if isinstance(eltype, dict):
        eltype = eltype[d['ndim']]
    return eltype


def print_catalog():
    for el in abq_elems:
        d = abq_eltype(el)
        if d:
            print("Eltype %s = Type %s, ndim %s, nplex %s, mod %s, pyf_type %s" % (el, d['type'], d['ndim'], d['nplex'], d['mod'], d['pyf']))
        else:
            print("No match: %s" % el)


#print_catalog()
#
#  TODO: S... and RAX elements are still scanned wrongly
#

class InpModel(object):
    pass

model = None
system = None
skip_unknown_eltype = False
log = None
part = None


def startPart(name):
    """Start a new part."""
    global part
    print("Start part %s" % name)
    model.parts.append({'name':name})
    part = model.parts[-1]


def readCommand(line):
    """Read a command line, return the command and a dict with options"""
    if line[0] == '*':
        line = line[1:]
    s = line.split(',')
    s = [si.strip() for si in s]
    cmd = s[0]
    opts = {}
    for si in s[1:]:
        kv = si.split('=')
        k = kv[0]
        if len(kv) > 1:
            v = kv[1]
        else:
            v = True
        opts[k] = v
    return cmd, opts


def do_HEADING(opts, data):
    """Read the nodal data"""
    model.heading = '\n'.join(data)


def do_PART(opts, data):
    """Set the part name"""
    startPart(opts['NAME'])


def do_SYSTEM(opts, data):
    """Read the system data"""
    global system
    if len(data) == 0:
        system = None
        return

    s = data[0].split(',')
    A = [float(v) for v in s[:3]]
    try:
        B = [float(v) for v in s[3:]]
    except:
        B, C = None, None
    if len(data) > 1:
        C = [float(v) for v in data[1].split('')]
    else:
        B[2] = 0.
        C = [ -B[1], B[0], 0. ]
    t = array(A)
    if B is None:
        r = None
    else:
        r = rotmat(array([A, B, C]))
    system = (t, r)


def do_NODE(opts, data):
    """Read the nodal data"""
    nnodes = len(data)
    print("Read %s nodes" % nnodes)
    ndata = len(data[0].split())
    data = ','.join(data)
    with open('%s-NODE.data'%part['name'], 'w') as f:
        f.write(data)

    x = np.fromstring(data, dtype=np.float32, count=ndata*nnodes, sep=',').reshape(-1, ndata)
    nodid = x[:, 0].astype(np.int32)
    coords = x[:, 1:]

    if system:
        t, r = system
        if r is not None:
            coords = dot(coords, r)
        coords += t

    if 'coords' in part:
        part['nodid'] = concatenate([part['nodid'], nodid])
        part['coords'] = concatenate([part['coords'], coords], axis=0)
    else:
        part['nodid'] = nodid
        part['coords'] = coords


def do_ELEMENT(opts, data):
    """Read element data"""
    d = abq_eltype(opts['TYPE'])
    eltype = d['pyf']
    if not eltype:
        if skip_unknown_eltype:
            return
        else:
            raise ValueError("Element type '%s' can not yet be imported" % opts['TYPE'])
    nplex = d['nplex']
    nelems = len(data)
    print("Read %s elements of type %s, plexitude %s" % (nelems, eltype, nplex))
    ndata = nplex+1
    data = ','.join(data)
    with open('%s-ELEMENT.data'%part['name'], 'w') as f:
        f.write(data)
    e = np.fromstring(data, dtype=np.int32, count=ndata*nelems, sep=',').reshape(-1, ndata)
    elid = e[:, 0]
    elems = e[:, 1:]
    if not 'elems' in part:
        part['elems'] = []
    if not 'elid' in part:
        part['elid'] = []
    part['elems'].append((eltype, elems))
    part['elid'].append(elid)


def endCommand(cmd, opts, data):
    global log
    func = 'do_%s' % cmd
    if func in globals():
        globals()[func](opts, data)
    else:
        #print("Data %s" % data)
        log.write("Don't know how to handle keyword '%s'\n" % cmd)


def readInput(fn):
    """Read an input file (.inp)

    Returns an object with the following attributes:

    - `heading`: the heading read from the .inp file
    - `parts`: a list with parts.

    A part is a dict and can contain the following keys:

    - `name`: string: the part name
    - `coords`: float (nnod,3) array: the nodal coordinates
    - `nodid`: int (nnod,) array: node numbers; default is arange(nnod)
    - `elems`: int (nelems,nplex) array: element connectivity
    - `elid`: int (nelems,) array: element numbers; default is arange(nelems)
    """
    global line, part, log, model
    dirname, basename, ext = utils.splitFilename(fn,['.inp'])
    logname = utils.buildFilename(dirname,basename+'_ccxinp.log')
    model = InpModel()
    model.parts = []
    startPart('DEFAULT')
    cmd = ''
    with open(logname, 'w') as log:
        with open(fn) as fil:
            data_cont = False
            data = []
            for line in fil:
                if len(line) == 0:
                    break
                line = line.upper()
                if line.startswith('*'):
                    if cmd:
                        endCommand(cmd, opts, data)
                        cmd = ''
                    if line[1] != '*':
                        data = []
                        cmd, opts = readCommand(line[1:])
                        log.write("Keyword %s; Options %s\n" % (cmd, opts))
                        data_cont = False
                else:
                    line = line.strip()
                    if data_cont:
                        data[-1] += line
                    else:
                        data.append(line)
                    data_cont = line.endswith(',')

    print("Number of parts in model: %s" % len(model.parts))
    return model


# End
