from django.db import models
from django.utils.text import slugify
from wagtail import blocks
from wagtail.admin.panels import FieldPanel
from wagtail.fields import StreamField
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


class CompetenceProfilePage(Page):
    parent_page_types = ['course.CoursePage']
    subpage_types = ['competence.CompetencePage']

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

    def full_clean(self, *args, **kwargs):
        self.slug = find_available_slug(slugify(f"{self.get_parent().slug}-competence", allow_unicode=True))
        super(CompetenceProfilePage, 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 CompetencePage(Page):
    parent_page_types = ['competence.CompetenceProfilePage']
    subpage_types = ['competence.PerformanceCriteria']
    competence_id = models.TextField(default='A1')
    items = StreamField([
        ('item', blocks.TextBlock()),
    ], use_json_field=True)

    content_panels = [
        FieldPanel('title'),
        FieldPanel('competence_id'),
    ]

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

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


class PerformanceCriteria(Page):
    parent_page_types = ['competence.CompetenceProfilePage']
    competence_id = models.TextField(default='A1.1')
    learning_unit = models.ForeignKey(
        'learnpath.LearningUnit',
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
    )

    content_panels = [
        FieldPanel('title'),
        FieldPanel('competence_id'),
        FieldPanel('learning_unit'),
    ]

    def full_clean(self, *args, **kwargs):
        profile_parent = self.get_ancestors().exact_type(CompetenceProfilePage).last()
        if self.learning_unit and self.learning_unit.course_category:
            self.slug = find_available_slug(slugify(f"{profile_parent.slug}-crit-{self.competence_id}-{self.learning_unit.course_category.title}", allow_unicode=True))
        else:
            self.slug = find_available_slug(slugify(f"{profile_parent.slug}-crit-{self.competence_id}", allow_unicode=True))
        super(PerformanceCriteria, self).full_clean(*args, **kwargs)

    @classmethod
    def get_serializer_class(cls):
        from vbv_lernwelt.competence.serializers import PerformanceCriteriaSerializer
        return PerformanceCriteriaSerializer

    def get_admin_display_title(self):
        if self.learning_unit and self.learning_unit.course_category:
            return f'{self.competence_id} ({self.learning_unit.course_category.title}) {self.draft_title[:30]}'
        else:
            return f'{self.competence_id} {self.draft_title[:30]}'