from __future__ import print_function

import os, sys, json, re

script_directory = os.path.dirname(os.path.abspath(__file__))
template_directory = os.path.abspath(os.path.join(script_directory,
                                                  'template'))
test_root_directory = os.path.abspath(os.path.join(script_directory,
                                                   '..', '..', '..'))


def get_template(basename):
    with open(os.path.join(template_directory, basename), "r") as f:
        return f.read()


def write_file(filename, contents):
    with open(filename, "w") as f:
        f.write(contents)


def read_nth_line(fp, line_number):
  fp.seek(0)
  for i, line in enumerate(fp):
    if (i + 1) == line_number:
      return line


def load_spec_json(path_to_spec):
    re_error_location = re.compile('line ([0-9]+) column ([0-9]+)')
    with open(path_to_spec, "r") as f:
        try:
          return json.load(f)
        except ValueError as ex:
          print(ex.message)
          match = re_error_location.search(ex.message)
          if match:
            line_number, column = int(match.group(1)), int(match.group(2))
            print(read_nth_line(f, line_number).rstrip())
            print(" " * (column - 1) + "^")
          sys.exit(1)