# -*- coding: utf-8 -*-
from __future__ import absolute_import, division, unicode_literals
from logging import getLogger

from . import common, sections
from ..plex_db import PlexDB
from .. import backgroundthread, app

LOG = getLogger('PLEX.sync.process_metadata')

COMMIT_TO_DB_EVERY_X_ITEMS = 500


class ProcessMetadataThread(common.LibrarySyncMixin,
                            backgroundthread.KillableThread):
    """
    Invoke once in order to process the received PMS metadata xmls
    """
    def __init__(self, current_time, processing_queue, update_progressbar):
        self.current_time = current_time
        self.processing_queue = processing_queue
        self.update_progressbar = update_progressbar
        self.last_section = sections.Section()
        self.successful = True
        super(ProcessMetadataThread, self).__init__()

    def start_section(self, section):
        if section != self.last_section:
            if self.last_section:
                self.finish_last_section()
            LOG.debug('Start or continue processing section %s', section)
            self.last_section = section
            # Warn the user for this new section if we cannot access a file
            app.SYNC.path_verified = False
        else:
            LOG.debug('Resume processing section %s', section)

    def finish_last_section(self):
        if (not self.should_cancel() and self.last_section and
                self.last_section.sync_successful):
            # Check for should_cancel() because we cannot be sure that we
            # processed every item of the section
            with PlexDB() as plexdb:
                # Set the new time mark for the next delta sync
                plexdb.update_section_last_sync(self.last_section.section_id,
                                                self.current_time)
            LOG.info('Finished processing section successfully: %s',
                     self.last_section)
        elif self.last_section and not self.last_section.sync_successful:
            LOG.warn('Sync not successful for section %s', self.last_section)
            self.successful = False

    def _get(self):
        item = {'xml': None}
        while not self.should_cancel() and item and item['xml'] is None:
            item = self.processing_queue.get()
            self.processing_queue.task_done()
        return item

    def run(self):
        LOG.debug('Starting %s thread', self.__class__.__name__)
        app.APP.register_thread(self)
        try:
            self._run()
        except Exception:
            from .. import utils
            utils.ERROR(notify=True)
        finally:
            app.APP.deregister_thread(self)
            LOG.debug('##===---- %s Stopped ----===##', self.__class__.__name__)

    def _run(self):
        # There are 2 sentinels: None for aborting/ending this thread, the dict
        # {'section': section, 'xml': None} for skipped/invalid items
        item = self._get()
        if item:
            section = item['section']
            processed = 0
            self.start_section(section)
        while not self.should_cancel():
            if item is None:
                break
            elif item['section'] != section:
                # We received an entirely new section
                self.start_section(item['section'])
                section = item['section']
            with section.context(self.current_time) as context:
                while not self.should_cancel():
                    if item is None or item['section'] != section:
                        break
                    self.update_progressbar(section,
                                            item['xml'][0].get('title'),
                                            section.count)
                    context.add_update(item['xml'][0],
                                       section_name=section.name,
                                       section_id=section.section_id,
                                       children=item['children'])
                    processed += 1
                    section.count += 1
                    if processed == COMMIT_TO_DB_EVERY_X_ITEMS:
                        processed = 0
                        context.commit()
                    item = self._get()
        self.finish_last_section()