from datetime import datetime, timedelta, date
from datetime import time as dtime
import logging
from django.db import models, transaction
from django.utils import timezone
from boards import utils
from boards.mdx_neboard import Parser
from boards.models import PostImage
import boards.models

__author__ = 'vurdalak'


NO_IP = '0.0.0.0'
POSTS_PER_DAY_RANGE = 7


class PostManager(models.Manager):
    @transaction.atomic
    def create_post(self, title: str, text: str, image=None, thread=None,
                    ip=NO_IP, tags: list=None, opening_posts: list=None):
        """
        Creates new post
        """

        is_banned = boards.models.Ban.objects.filter(ip=ip).exists()

        # TODO Raise specific exception and catch it in the views
        if is_banned:
            raise Exception("This user is banned")

        if not tags:
            tags = []
        if not opening_posts:
            opening_posts = []

        posting_time = timezone.now()
        new_thread = False
        if not thread:
            thread = boards.models.thread.Thread.objects.create(
                bump_time=posting_time, last_edit_time=posting_time)
            list(map(thread.tags.add, tags))
            boards.models.thread.Thread.objects.process_oldest_threads()
            new_thread = True

        pre_text = Parser().preparse(text)

        post = self.create(title=title,
                           text=pre_text,
                           pub_time=posting_time,
                           poster_ip=ip,
                           thread=thread,
                           last_edit_time=posting_time)
        post.threads.add(thread)

        post.set_global_id()

        logger = logging.getLogger('boards.post.create')

        logger.info('Created post {} by {}'.format(post, post.poster_ip))

        if image:
            post.images.add(PostImage.objects.create_with_hash(image))

        if not new_thread:
            thread.last_edit_time = posting_time
            thread.bump()
            thread.save()

        post.build_url()
        post.connect_replies()
        post.connect_threads(opening_posts)
        post.connect_notifications()

        return post

    @transaction.atomic
    def import_post(self, title: str, text: str, pub_time: str,
                    opening_post=None, tags=list()):
        if opening_post is None:
            thread = boards.models.thread.Thread.objects.create(
                bump_time=pub_time, last_edit_time=pub_time)
            list(map(thread.tags.add, tags))
        else:
            thread = opening_post.get_thread()

        post = self.create(title=title, text=text,
                           pub_time=pub_time,
                           poster_ip=NO_IP,
                           last_edit_time=pub_time,
                           thread_id=thread.id)

        post.build_url()
        post.connect_replies()
        post.connect_notifications()

        return post

    def delete_posts_by_ip(self, ip):
        """
        Deletes all posts of the author with same IP
        """

        posts = self.filter(poster_ip=ip)
        for post in posts:
            post.delete()

    @utils.cached_result()
    def get_posts_per_day(self) -> float:
        """
        Gets average count of posts per day for the last 7 days
        """

        day_end = date.today()
        day_start = day_end - timedelta(POSTS_PER_DAY_RANGE)

        day_time_start = timezone.make_aware(datetime.combine(
            day_start, dtime()), timezone.get_current_timezone())
        day_time_end = timezone.make_aware(datetime.combine(
            day_end, dtime()), timezone.get_current_timezone())

        posts_per_period = float(self.filter(
            pub_time__lte=day_time_end,
            pub_time__gte=day_time_start).count())

        ppd = posts_per_period / POSTS_PER_DAY_RANGE

        return ppd