import logging;
from .common import State
from taskdatabase.models import Task, Activity

logger = logging.getLogger(__name__)

def calculate_ingested_fraction(this_task):
    """
    This 'property' of a task returns the fraction of queued/ingested tasks per SAS_ID
    and a list of statusses of other tasks belonging to the same SAS_ID.
    It is implemented as 'property', because then it can be used in html pages like this:
       <td>{{ task.sasid_ingested_fraction.status }}</td>
       <td>{{ task.sasid_ingested_fraction.completion }}%</td>

    A selection of statusses are considered 'queued', and another selection is considered 'ingested'.
    The division of those 2 are returned as a 'completed %'.
    A limited list of statusses for the other tasks that belong to this SAS_ID is also returned.

    """
    result = {}
    statusses = {'scrubbed': 0, 'archiving': 0, 'archived': 0, 'finishing': 0, 'finished': 0,
                 'suspended': 0, 'discarded': 0, 'archived_failed': 0, 'finished_failed': 0}

    tasks = Task.objects.filter(sas_id=this_task.sas_id)

    for task in tasks:
        try:
            statusses[task.status] += 1
        except:
            pass

    incomplete = int(statusses['scrubbed']) + int(statusses['archiving']) + int(statusses['finishing']) + \
                 int(statusses['suspended']) + int(statusses['archived_failed']) + int(statusses['finished_failed'])
    complete = int(statusses['archived']) + int(statusses['finished'])
    completion = round(complete / (incomplete + complete) * 100)

    non_zero_statusses = {key: value for key, value in statusses.items() if value != 0}

    result['status'] = non_zero_statusses
    result['completion'] = completion
    return result


def associate_activity(task, save_task=True):

    if not task.activity:

        try:
            activity = Activity.objects.get(sas_id=task.sas_id)
        except:
            # no activity exists yet, create it
            logger.info(f'create new activity for sas_id {task.sas_id}')

            activity = Activity(sas_id=task.sas_id,
                                workflow=task.workflow,
                                project=task.project,
                                filter=task.filter,
                                priority=task.priority,
                                archive=task.archive)
            activity.save()

        task.activity = activity
        if save_task:
            task.save()

    return task.activity

def update_activity(task):
    """
    The activity (SAS_ID level) is updated whenever a task change status.
    Depending on the type of status change, certain calculations and updates are performed.
    Doing this on status change, instead of on-the-fly when a user enters a page, balances the load.

    - to '???'                                   : check for incoming 'archive' json from archiver
    - to STORED                                  : calculate quality
    - to ???                                     : calculate finished_fraction
    - to SCRUBBED, ARCHIVING, ARCHIVED, FINISHED : calculate ingested_fraction

    """
    logger.info(f'update_activity for task {task.id} with sas_id {task.sas_id} and status {task.status}')

    # do not save the task,
    # because this function is called from signals where the task.save is delayed on purpose to avoid recursion
    activity = associate_activity(task, save_task=False)

    # depending on the status transition, perform calculations
    if task.status == State.STORED.value:
        logger.info(f'- calculate_qualities')
        # quality is calculated per task and per sas_id, reget the quality per sas_id
        try:
            activity.calculated_quality = task.calculated_qualities['per_sasid']
            activity.save()
        except:
            pass

    # calculate the fraction and list of statusses of ingested tasks of this SAS_ID
    if task.status in [State.SCRUBBED.value, State.ARCHIVING.value, State.ARCHIVED.value, State.FINISHING.value]:
        logger.info(f'- calculate_ingested_fraction')
        result = calculate_ingested_fraction(task)
        activity.ingested_fraction = result['completion']
        activity.ingestq_status = result['status']
        activity.save()


    # check of any task of this activity already has LTA information. If so, copy to the activity level
    if task.status in [State.ARCHIVING.value, State.ARCHIVED.value, State.FINISHING.value]:
        logger.info(f'- add archive json')
        for t in Task.objects.filter(sas_id=task.sas_id):
            try:
                if t.archive['sas_id_archived']:
                    activity.archive = t.archive
                    break
            except:
                pass

        activity.save()