# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Library General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
#
# Copyright 2006 Dan Williams <dcbw@redhat.com> and Red Hat, Inc.

import threading
import URLopener
import time



FT_RESULT_SUCCESS = 'success'
FT_RESULT_FAILED = 'failed'
FT_RESULT_CANCELED = 'canceled'


class FileTransfer(threading.Thread):
    def __init__(self, certs=None):
        self._callback = None
        self._cb_data = None
        self._cancel = False
        self._tries = 5
        self._opener = None

        if certs:
            if type(certs) is not type({}):
                raise ValueError("Certs must be a dict of certificate paths.")
        self._certs = certs

        self._opener = URLopener.PlgURLopener(self._certs, 20)

        threading.Thread.__init__(self)

    def set_tries(self, tries):
        if tries <= 0:
            raise ValueError("Tries must be larger than 0")
        self._tries = tries

    def set_callback(self, callback, cb_data):
        self._callback = callback
        self._cb_data = cb_data

    def cancel(self):
        self._cancel = True

    def _action(self, data=None):
        # Should be implemented by subclasses
        return (False, "_action should be implemented by subclass")

    def _process_one_transfer(self, data=None):
        """Retries a transfer for a specified number of times before failing."""
        status = FT_RESULT_FAILED
        result = msg = filed_msg = None
        for attempt in range(1, self._tries + 1):
            try:
                (result, msg) = self._action(data)
            except ValueError, exc:
                result = None
                failed_msg = str(exc)
            if result:
                status = FT_RESULT_SUCCESS
                break
            if self._cancel:
                status = FT_RESULT_CANCELED
                break
            time.sleep(5)
            failed_msg = "Transfer timed out."
        if status == FT_RESULT_FAILED:
            msg = failed_msg
        return (status, msg)

    def run(self):
        (status, msg) = self._process_one_transfer()
        if self._callback:
            self._callback(status, self._cb_data, msg)