from django.db import models
from django.conf import settings

from functools import cached_property
from pathlib import Path
from urllib.parse import quote
import mimetypes
import uuid
import shlex


class Torrent(models.Model):
    id = models.CharField(max_length=40, primary_key=True)
    name = models.CharField(max_length=255)
    date_created = models.DateTimeField(auto_now_add=True)
    date_modified = models.DateTimeField(auto_now=True)
    user = models.ForeignKey("user.User", on_delete=models.CASCADE, related_name="torrents")
    shared_users = models.ManyToManyField("user.User", related_name="torrents_shares", blank=True, through="SharedUser")
    size = models.PositiveBigIntegerField()
    transmission_data = models.JSONField(default=dict)

    @cached_property
    def len_files(self):
        if hasattr(self, "_len_files"):
            return self._len_files
        else:
            return File.objects.filter(torrent_id=self.id).count()

    @property
    async def alen_files(self):
        if hasattr(self, "_len_files"):
            return self._len_files
        else:
            return await File.objects.filter(torrent_id=self.id).acount()

    @cached_property
    def related_users(self):
        return [
            self.user_id,
            *self.shared_users.values_list("id", flat=True)
        ]


class SharedUser(models.Model):
    user = models.ForeignKey("user.User", models.CASCADE)
    torrent = models.ForeignKey("Torrent", models.CASCADE)
    date_created = models.DateTimeField(auto_now_add=True)

    class Meta:
        unique_together = ("user", "torrent")



class File(models.Model):
    id = models.UUIDField(primary_key=True, default=uuid.uuid4)
    torrent = models.ForeignKey("Torrent", models.CASCADE, related_name="files")
    rel_name = models.TextField()
    size = models.BigIntegerField()

    @property
    def pathname(self):
        return Path(self.rel_name)

    @property
    def filename(self):
        return self.pathname.name

    @property
    def abs_pathname(self):
        return settings.DOWNLOAD_BASE_DIR / self.pathname

    @property
    def mime_types(self):
        mime = mimetypes.guess_type(self.pathname)
        if mime:
            return mime
        else:
            return "application/octet-stream"

    @property
    def is_stream_video(self):
        return self.pathname.stem in ["mp4", "flv", "webm"]

    @property
    def is_video(self):
        return self.pathname.stem in ["mp4", "flv", "webm", "avi", "mkv"]

    @property
    def accel_redirect(self):
        return shlex.quote(f"{settings.NGINX_ACCEL_BASE}/{self.pathname}")

    @property
    def disposition(self):
        return f'attachment; filename="{quote(self.filename)}"; filename*="{quote(self.filename)}"'