from django.db import models
from django.utils.text import slugify
from wagtail import fields
from wagtail.admin.panels import FieldPanel, StreamFieldPanel
from wagtail.documents.models import AbstractDocument, Document
from wagtail.models import Page

from vbv_lernwelt.core.model_utils import find_available_slug
from vbv_lernwelt.learnpath.serializer_helpers import get_it_serializer_class
from vbv_lernwelt.media_library.content_blocks import MediaContentCollection


class MediaLibraryPage(Page):
    parent_page_types = ['course.CoursePage']
    subpage_types = ['media_library.MediaCategoryPage']

    content_panels = [
        FieldPanel('title', classname="full title"),
    ]

    def full_clean(self, *args, **kwargs):
        self.slug = find_available_slug(slugify(f"{self.get_parent().slug}-media", allow_unicode=True))
        super(MediaLibraryPage, self).full_clean(*args, **kwargs)

    @classmethod
    def get_serializer_class(cls):
        return get_it_serializer_class(
            cls, [
                'id', 'title', 'slug', 'type', 'translation_key',
                'course',
                'children',
            ]
        )


class MediaCategoryPage(Page):
    """
    Handlungsfeld. zB. Fahrzeug
    """
    course_category = models.ForeignKey('course.CourseCategory', on_delete=models.CASCADE)
    parent_page_types = ['media_library.MediaLibraryPage']
    introduction_text = models.TextField(default='')
    description = fields.RichTextField(default='')

    body = fields.StreamField(
        [('content_collection', MediaContentCollection())],
        use_json_field=True,
        null=True
    )

    content_panels = [
        FieldPanel('title', classname="full title"),
        FieldPanel('course_category'),
        FieldPanel('introduction_text', classname="introduction text"),
        FieldPanel('description', classname="introduction text"),
        StreamFieldPanel('body')
    ]

    def full_clean(self, *args, **kwargs):
        self.slug = find_available_slug(slugify(f"{self.get_parent()}-cat-{self.title}", allow_unicode=True))
        super(MediaCategoryPage, self).full_clean(*args, **kwargs)

    @classmethod
    def get_serializer_class(cls):
        return get_it_serializer_class(
            cls, field_names=[
                'id', 'title', 'slug', 'type', 'translation_key',
                'course_category',
                'introduction_text', 'description', 'body',
            ]
        )


class LibraryDocument(AbstractDocument):
    # Todo: check https://filepreviews.io/

    # Custom field example:
    display_text = models.CharField(max_length=1024, default='')
    description = models.TextField(default='')
    link_display_text = models.CharField(max_length=1024, default='')
    thumbnail = models.URLField()

    admin_form_fields = Document.admin_form_fields + (
        'display_text', 'description', 'link_display_text', 'thumbnail'
    )