"""Main entry data"""
import os
from django.conf import settings
from django.db import models
from django.utils import timezone
from django.utils.html import format_html

from pulseapi.tags.models import Tag
from pulseapi.issues.models import Issue
from pulseapi.helptypes.models import HelpType
from pulseapi.users.models import EmailUser


def entry_thumbnail_path(instance, filename):
    return 'images/entries/{timestamp}{ext}'.format(
        timestamp=str(timezone.now()),
        ext=os.path.splitext(filename)[1]
    )


# Create your models here.
class ModerationState(models.Model):
    name = models.CharField(max_length=100)

    def __str__(self):
        return str(self.name)


def get_default_moderation_state():
    """
    Helper function to ensure there is a default
    ModerationState that can be tacked onto Entries.
    """

    states = ModerationState.objects.all()
    if len(states) == 0:
        return -1

    default_state = states[0].id
    return default_state


class EntryQuerySet(models.query.QuerySet):
    """
    A queryset for entries which returns all entries
    """

    def public(self):
        """
        Return all entries that have been approved
        """
        return self.filter(moderation_state__name='Approved')

    def with_related(self):
        """
        Return all entries with their related data as separate queries
        """

        return self.prefetch_related(
            'tags',
            'issues',
            'help_types',
            'published_by',
            'bookmarked_by',
            'bookmarked_by__profile__related_user',
            'published_by__profile',
            'moderation_state',
            'related_entry_creators__profile__related_user',
        )

    def by_active_profile(self):
        """
        Return all entries that have been created by pulse users who's profiles are set to "Active" by moderator.
        """
        return self.filter(published_by__profile__is_active=True)


class Entry(models.Model):
    """
    A pulse entry
    """
    ENTRY_TYPES = (
        ('base', 'base'),
        ('project', 'project'),
        ('news', 'news'),
        ('curriculum', 'curriculum'),
        ('research', 'research'),
        ('session', 'session'),
    )

    # required fields
    entry_type = models.CharField(
        max_length=20,
        choices=ENTRY_TYPES,
        default=ENTRY_TYPES[0][0],
    )
    title = models.CharField(max_length=140)
    content_url = models.URLField(
        blank=True,
    )

    # optional fields
    description = models.CharField(max_length=600, blank=True)
    get_involved = models.CharField(max_length=300, blank=True)
    get_involved_url = models.URLField(blank=True)
    interest = models.CharField(max_length=600, blank=True)
    featured = models.BooleanField(default=False)
    internal_notes = models.TextField(blank=True)
    published_by_creator = models.BooleanField(default=False)

    # thumbnail image
    thumbnail = models.ImageField(
        max_length=2048,
        upload_to=entry_thumbnail_path,
        blank=True
    )

    def thumbnail_image_tag(self):
        if not self.thumbnail:
            return format_html('<span>No image to preview</span>')

        media_url = settings.MEDIA_URL

        if settings.USE_S3:
            media_url = 'https://{domain}/{bucket}/'.format(
                domain=settings.AWS_S3_CUSTOM_DOMAIN,
                bucket=settings.AWS_LOCATION
            )

        html = '<img src="{media_url}{src}" style="width:25%">'.format(
            media_url=media_url,
            src=self.thumbnail
        )

        return format_html(html)

    thumbnail_image_tag.short_description = 'Thumbnail preview'

    # crosslink fields
    tags = models.ManyToManyField(
        Tag,
        related_name='entries',
        blank=True
    )
    issues = models.ManyToManyField(
        Issue,
        related_name='entries',
        blank=True
    )
    help_types = models.ManyToManyField(
        HelpType,
        related_name='entries',
        blank=True
    )

    # automatically managed fields
    published_by = models.ForeignKey(
        EmailUser,
        related_name='entries',
        on_delete=models.CASCADE
    )
    created = models.DateTimeField(
        default=timezone.now
    )

    # moderation information
    moderation_state = models.ForeignKey(
        ModerationState,
        related_name='entries',
        default=get_default_moderation_state,
        on_delete=models.PROTECT
    )

    def set_moderation_state(self, state_name):
        (moderation_state, created) = ModerationState.objects.get_or_create(
            name=state_name
        )
        self.moderation_state = moderation_state

    def is_approved(self):
        return self.moderation_state.name == 'Approved'

    objects = EntryQuerySet.as_manager()

    def frontend_entry_url(self):
        return '{frontend_url}/entry/{pk}'.format(frontend_url=settings.PULSE_FRONTEND_HOSTNAME, pk=self.id)

    class Meta:
        """
        Make plural not be wrong
        """
        verbose_name_plural = "entries"
        ordering = ['-id']
        permissions = (
            ('change_creators', 'Can change the creators for entries'),
        )

    def __str__(self):
        return str(self.title)