#!/usr/bin/env python
# -*- coding: utf-8 -*-
"""\
Material database.
"""
__author__ = "Daniel Weschke"
__copyright__ = "Copyright 2019 Daniel Weschke"
__credits__ = ["Daniel Weschke"]
__license__ = "MIT"
__version__ = "2019.02.03"
__maintainer__ = "Daniel Weschke"
__email__ = "daniel.weschke@directbox.de"
__status__ = "Production"  # "Prototype", "Development", "Production"

VERSION = """\
%(prog)s version {version} {copyright}
""".format(
  version=__version__, copyright=__copyright__)

EPILOG = """\
"""

def list_files():
  """\
  List all materials
  """
  from os import listdir

  for data in listdir("./data"):
    file_name = data.split('.')[0]
    if file_name != "INFO":
      print(file_name)

def read(input_file, search_keys=None):
  """\
  Read json file
  """
  import os
  import json
  from pprint import pprint

  def find_values(key, json_repr):
    results = []

    def _decode_dict(a_dict):
      try:
        results.append(a_dict[key])
      except KeyError:
        pass
      return a_dict

    json.loads(json_repr, object_hook=_decode_dict)  # return value ignored
    return results

  try:
    with open(os.path.join('data', input_file + '.json')) as data_file:
      if search_keys is not None:
        data = data_file.read()
        for search_key in search_keys:
          found_values = find_values(search_key, data)
          #print(found_values)
          for value in found_values:
            #print('%-5s' % value[0] + ' ' + value[1])
            print(search_key + ' = ' + '%s' % value[0] + ' ' + value[1])

        #def getLength(element):
        #  try:
        #    element.__iter__
        #    return sum([getLength(i) for i in element])
        #  except:
        #    return 1
        #print(len(data))
        #print(getLength(json.loads(data)))

      else:
        data = json.load(data_file)
        pprint(data)

  except (OSError, IOError) as err:
    print(str(err))
    sys.exit(2)


def main():
  """\
  Main function
  """
  import argparse

  parser = argparse.ArgumentParser(
    description=__doc__, prefix_chars='-', epilog=EPILOG,
    #usage="%(prog)s [OPTION]... NAME",
    formatter_class=argparse.RawTextHelpFormatter,
  )
  parser.add_argument('-v', '--verbose', action="store_true", help="Verbose output")
  parser.add_argument('-V', '--version', action='version', version=VERSION)
  parser.add_argument('-D', '--debug', dest='debug', action='store_true', help=argparse.SUPPRESS)

  subparsers = parser.add_subparsers(help='commands', dest='command')

  # list materials
  parser_list = subparsers.add_parser('list',
                                      description='List materials.',
                                      help='list all available materials')

  # material
  parser_material = subparsers.add_parser('material',
                                          help='the material to get information from')
  parser_material.add_argument('materialname', action='store',
                               help='list available material information')
  parser_material.add_argument('-r', '--rho', dest='const_collection',
                               action='append_const', const="rho",
                               help='get density from material')
  parser_material.add_argument('-T', '--Tm', dest='const_collection',
                               action='append_const', const="T_m",
                               help='get melting point temperature')

  args = parser.parse_args()

  if args.debug:
    print(args)

  if args.command == 'list':
    list_files()

  elif args.command == 'material':
    if args.const_collection:
      read(args.materialname, search_keys=args.const_collection)
    else:
      read(args.materialname)

  return 0

if __name__ == "__main__":
  import sys
  sys.exit(main())