#  This file is part of ReportTool

# ReportTool (Felicity) is copyright 2004-8 Steve Butterfill.
# 
# ReportTool 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.
# 
# ReportTool 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 General Public License for more details.
# 
# You should have received a copy of the GNU General Public License
# along with ReportTool.  If not, see <http://www.gnu.org/licenses/>.
# 
# If you want to use ReportTool under a difference licence, email 
# s.butterfill@warwick.ac.uk.  

#!/usr/bin/env python

# --------------------------
# threads for uploading
# partly based on
# http://groups.google.com/group/turbogears/browse_thread/thread/2be56c7df244f837/98eb9e9b4efa36a
# --------------------------

import sys, threading, traceback
from felicity.hacks import safe_str
from felicity.model import hub, Job, UploadDataSet
from sqlobject.util.threadinglocal import local as threading_local

#global lock -- only one upload runs at once
upload_mutex = threading.Lock()

def start_upload_thread(file, delimiter, dataset, upload_function, job):
    """threaded version of omr upload
    """
    dataset_id = None
    if dataset is not None:
        dataset_id = dataset.id
    ult = UploadThread(file=file, delimiter=delimiter, dataset_id=dataset_id,
                       upload_function = upload_function, job_id=job.id)
    job.update_progress("Waiting in queue for processing to start.")
    ult.start()


class UploadThread(threading.Thread):
    def __init__(self, file, delimiter, dataset_id, upload_function, job_id):
        self.file = file
        self.delimiter = delimiter
        self.dataset_id = dataset_id
        self.upload_function = upload_function
        self.job_id = job_id
        threading.Thread.__init__(self)
    
    def run(self):
        # This part is important, it gives us a new connection for this
        # thread, otherwise your thread will get messy db access
        try:
            hub.threadingLocal = threading_local()
            hub.begin()
            job = Job.get(self.job_id)
            dataset = None
            if self.dataset_id is not None:
                dataset = UploadDataSet.get(self.dataset_id)
            upload_mutex.acquire()
            result = self.upload_function(file=self.file, delimiter=self.delimiter,
                                          dataset=dataset, job=job)
        except:
            try:
                exc_info = sys.exc_info()
                error_msg = traceback.format_exception(*exc_info)
                hub.rollback()
                hub.begin()
                job.failed(safe_str(error_msg))
                hub.commit()
                raise exc_info[0], exc_info[1], exc_info[2]
            except:
                print >> sys.stderr, "Error in UploadThread exception handler"
                traceback.print_exc()
        else:
            hub.commit()
            hub.begin()
            job.done(result)
            hub.commit()
        upload_mutex.release()