import hashlib
import os
import uuid
from os.path import isfile, join

from django.db import models
from django.urls import reverse
from django.core.files import File
from django.utils.translation import gettext_lazy as _
from django.db.models import Q
from django.utils import timezone

from imagebot import settings


def get_hash(filepath):
    with open(filepath, 'rb') as file:
        # read contents of the file
        data = file.read()
        sha256 = hashlib.sha256(data).hexdigest()
        return sha256


class Image(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4, verbose_name=_('ID'))
    title = models.CharField(max_length=200,
                             help_text=_("Image title that will be posted"),
                             blank=True, null=True)
    alt_text = models.TextField(help_text=_("Describe the image"),
                                blank=True, null=True)
    file_path = models.CharField(max_length=1500)
    image = models.ImageField()
    file_hash = models.CharField(verbose_name=_('File hash'), max_length=64, blank=True, null=True, unique=True)
    last_posted = models.DateTimeField(blank=True, null=True)
    number_times_posted = models.IntegerField(default=0)

    def __str__(self):
        if self.title:
            return self.title
        else:
            return f"{self.file_hash}"

    def get_absolute_url(self):
        return reverse("image-update", args=[self.id])

    def set_image_posted(self):
        self.number_times_posted += 1
        self.last_posted = timezone.now()
        self.save()

    @staticmethod
    def consume():
        files = [f for f in settings.MEDIA_CONSUME_DIR.iterdir() if f.is_file()]

        for path in files:
            file_hash = get_hash(path)
            with open(path, 'rb') as f:
                django_file = File(f, name=settings.MEDIA_PROCESSED_DIR_RELATIVE / path.name)

                img = Image.objects.create(
                    file_path=str(path),
                    image=django_file,
                    file_hash=file_hash
                )
            os.remove(path)

    @staticmethod
    def get_image_for_descriptor():
        image = Image.objects.filter(Q(alt_text=None) | Q(title=None)).first()
        return image

    @staticmethod
    def get_image_to_post():
        image = Image.objects.filter(Q(alt_text__isnull=False) & Q(title__isnull=False)).order_by('last_posted').first()
        return image