"""An object-oriented interface to .netrc files."""

# Module and documentation by Eric S. Raymond, 21 Dec 1998

import os, shlex, stat

__all__ = ["netrc", "NetrcParseError"]


class NetrcParseError(Exception):
 """Exception raised on syntax errors in the .netrc file."""
 def __init__(self, msg, filename=None, lineno=None):
 self.filename = filename
 self.lineno = lineno
 self.msg = msg
 Exception.__init__(self, msg)

 def __str__(self):
 return "%s (%s, line %s)" % (self.msg, self.filename, self.lineno)


class netrc:
 def __init__(self, file=None):
 default_netrc = file is None
 if file is None:
 file = os.path.join(os.path.expanduser("~"), ".netrc")
 self.hosts = {}
 self.macros = {}
 with open(file) as fp:
 self._parse(file, fp, default_netrc)

 def _parse(self, file, fp, default_netrc):
 lexer = shlex.shlex(fp)
 lexer.wordchars += r"""!"#$%&'()*+,-./:;<=>?@[\]^_`{|}~"""
 lexer.commenters = lexer.commenters.replace('#', '')
 while 1:
 # Look for a machine, default, or macdef top-level keyword
 saved_lineno = lexer.lineno
 toplevel = tt = lexer.get_token()
 if not tt:
 break
 elif tt[0] == '#':
 if lexer.lineno == saved_lineno and len(tt) == 1:
 lexer.instream.readline()
 continue
 elif tt == 'machine':
 entryname = lexer.get_token()
 elif tt == 'default':
 entryname = 'default'
 elif tt == 'macdef': # Just skip to end of macdefs
 entryname = lexer.get_token()
 self.macros[entryname] = []
 lexer.whitespace = ' \t'
 while 1:
 line = lexer.instream.readline()
 if not line or line == '012円':
 lexer.whitespace = ' \t\r\n'
 break
 self.macros[entryname].append(line)
 continue
 else:
 raise NetrcParseError(
 "bad toplevel token %r" % tt, file, lexer.lineno)

 # We're looking at start of an entry for a named machine or default.
 login = ''
 account = password = None
 self.hosts[entryname] = {}
 while 1:
 tt = lexer.get_token()
 if (tt.startswith('#') or
 tt in {'', 'machine', 'default', 'macdef'}):
 if password:
 self.hosts[entryname] = (login, account, password)
 lexer.push_token(tt)
 break
 else:
 raise NetrcParseError(
 "malformed %s entry %s terminated by %s"
 % (toplevel, entryname, repr(tt)),
 file, lexer.lineno)
 elif tt == 'login' or tt == 'user':
 login = lexer.get_token()
 elif tt == 'account':
 account = lexer.get_token()
 elif tt == 'password':
 if os.name == 'posix' and default_netrc:
 prop = os.fstat(fp.fileno())
 if prop.st_uid != os.getuid():
 import pwd
 try:
 fowner = pwd.getpwuid(prop.st_uid)[0]
 except KeyError:
 fowner = 'uid %s' % prop.st_uid
 try:
 user = pwd.getpwuid(os.getuid())[0]
 except KeyError:
 user = 'uid %s' % os.getuid()
 raise NetrcParseError(
 ("~/.netrc file owner (%s) does not match"
 " current user (%s)") % (fowner, user),
 file, lexer.lineno)
 if (prop.st_mode & (stat.S_IRWXG | stat.S_IRWXO)):
 raise NetrcParseError(
 "~/.netrc access too permissive: access"
 " permissions must restrict access to only"
 " the owner", file, lexer.lineno)
 password = lexer.get_token()
 else:
 raise NetrcParseError("bad follower token %r" % tt,
 file, lexer.lineno)

 def authenticators(self, host):
 """Return a (user, account, password) tuple for given host."""
 if host in self.hosts:
 return self.hosts[host]
 elif 'default' in self.hosts:
 return self.hosts['default']
 else:
 return None

 def __repr__(self):
 """Dump the class data in the format of a .netrc file."""
 rep = ""
 for host in self.hosts.keys():
 attrs = self.hosts[host]
 rep += f"machine {host}\n\tlogin {attrs[0]}\n"
 if attrs[1]:
 rep += f"\taccount {attrs[1]}\n"
 rep += f"\tpassword {attrs[2]}\n"
 for macro in self.macros.keys():
 rep += f"macdef {macro}\n"
 for line in self.macros[macro]:
 rep += line
 rep += "\n"
 return rep

if __name__ == '__main__':
 print(netrc())