#!/usr/bin/env python

__author__ = "Jan Pokorny <jpokorny at redhat dot com>"
__license__ = "GPLv2"


# couple of observations:
# - function name placeholder:
#   - <signal handler called>
# - single argument placeholder:
#   - how=how@entry=0
# + totally skewed by Python-aware annotations :-/


from sys import stdin, stderr
from re import compile
from textwrap import fill, wrap

DEF_PATH = '[A-Za-z0-9._/-]+'
DEF_IDENT = '[A-Za-z_][A-Za-z0-9_]*'
# incl. C++ stuff
DEF_IDENT_FUNC = '%(DEF_IDENT)s(?:(?: |::)%(DEF_IDENT)s)*' % locals()
# incl. "how=how@entry" in how=how@entry=0 and the like
DEF_IDENT_ARG = '(?P<atnotation>[A-Za-z_][A-Za-z0-9_]*)(=(?P=atnotation)@[A-Za-z0-9_]+)?'

DEF_UNKNOWN = '[?]{2}'
DEF_HEX = '0x[0-9A-Fa-f]+'
DEF_NUM = '[+-]?(?:[0-9]+(?:[.][0-9]*)?|[.][0-9]+)(?:[eE][0-9]+)?'
DEF_MSG = '(?:%(DEF_HEX)s\s+)?[<][ A-Za-z0-9_.]+[>]' % locals()
DEF_STR = '(?:%(DEF_HEX)s\s+)?["][^"]*["]' % locals()
DEF_STR2 = "(?:%(DEF_HEX)s\s+)?['][^']*[']" % locals()
DEF_STRUCT = '(?:%(DEF_HEX)s\s+=\s+)?[{][^}]*[}]' % locals()
DEF_PYTHONFRAME = 'Frame %(DEF_HEX)s, for file %(DEF_PATH)s, line \d+, in %(DEF_IDENT)s [(][^)]*[)]' % locals()

RE_BT = compile(
    '(?P<init>^\#[0-9]+\s+)'
    '(?:(?P<hex>%(DEF_HEX)s) in )?'
    '(?P<where>%(DEF_IDENT_FUNC)s|(?P<unknown>%(DEF_UNKNOWN)s|%(DEF_MSG)s))'
    '(?: (?P<args>[(](?:(?<=[( ])%(DEF_IDENT_ARG)s=(?:%(DEF_IDENT)s|%(DEF_MSG)s|%(DEF_PYTHONFRAME)s|%(DEF_HEX)s|%(DEF_NUM)s|%(DEF_STR)s|%(DEF_STR2)s|%(DEF_STRUCT)s)(?:, )?)*[)])'
    '(?(unknown)| at (?P<path>%(DEF_PATH)s):(?P<line>[1-9][0-9]*)))?'
    % locals())


class BtLineError(Exception):
    def __init__(self, string):
        self._string = string

    def __str__(self):
        return self._string


class BtLine(object):

    def __init__(self, line, space=' ' * 4):
        self._space = space
        self._line = line
        self._found = RE_BT.search(self._line)
        if self._found:
            for k, v in self._found.groupdict().iteritems():
                #print >>stderr, "\t{0}: {1}".format(k, v)
                setattr(self, k, v if v is not None else '')
        else:
            raise BtLineError(fill(line.strip(), initial_indent=self._space * 2,
                                   subsequent_indent=self._space * 3))

    def __str__(self):
        if self._found:
            args = wrap(self.args, subsequent_indent=self._space)
            space = '\n' + self._space
            res = self.init + self.where
            if args and args[0] != '()':
                res += space + '\n'.join(args)
            if self.path:
                res += space + 'at ' + self.path + ':' + self.line
            return res


def main(**kwargs):
    line = '__dummy__'
    firstline = True
    cnt = 1
    while line != '':
        cnt += 1
        line = stdin.readline()
        if not line.strip():
            # unfortunately, textwrap.fill would alias, e.g., '\n' and '' cases
            print line
            continue
        try:
            btline = BtLine(line, **kwargs)
            print ('' if firstline else '\n') + str(btline)
        except BtLineError as ble:
            line = str(ble)
            print >>stderr, ">> bad line:%i" % cnt
            print line
        finally:
            firstline = False


if __name__ == '__main__':
    main()