#

# Dblatex Error Handler wrapper providing:

# - The ErrorHandler class definition, that must be the parent of any actual

#   error handler.

# - A general API.

#

from __future__ import print_function

import sys

import traceback

class ErrorHandler(object):

    """

    Object in charge to handle any error occured during the dblatex

    transformation process. The first mandatory argument is the <object>

    that signaled the error.

    """

    def __init__(self):

        pass

    def signal(self, object, *args, **kwargs):

        failure_track("Unexpected error occured")

_current_handler = None

_dump_stack = False

#

# Dblatex Error Handler API

#

# In a complex use of the API, a locking mechanism (thread.lock) should

# be used. The current implementation assumes that setup is done before

# any get().

#

def get_errhandler():

    global _current_handler

    # If nothing set, use a default handler that does nothing

    if not(_current_handler):

        _current_handler = ErrorHandler()

    return _current_handler

def set_errhandler(handler):

    global _current_handler

    if not(isinstance(handler, ErrorHandler)):

        raise ValueError("%s is not an ErrorHandler" % handler)

    _current_handler = handler

def signal_error(*args, **kwargs):

    get_errhandler().signal(*args, **kwargs)

def failure_track(msg):

    global _dump_stack

    print((msg), file=sys.stderr)

    if _dump_stack:

        traceback.print_exc()

def failed_exit(msg, rc=1):

    failure_track(msg)

    sys.exit(rc)

def dump_stack():

    global _dump_stack

    _dump_stack = True