# Create your models here.

from django.utils.text import slugify
from wagtail.core.blocks import StreamBlock
from wagtail.core.fields import StreamField
from wagtail.core.models import Page, Orderable
from wagtail.api import APIField

from vbv_lernwelt.learnpath.models_competences import *
from vbv_lernwelt.learnpath.models_learning_unit_content import WebBasedTrainingBlock, VideoBlock
from grapple.helpers import register_query_field
from collections import OrderedDict
import graphene

from grapple.models import (
    GraphQLString, GraphQLPage,
    GraphQLStreamfield, GraphQLBoolean, GraphQLInt, GraphQLForeignKey, GraphQLField
)


@register_query_field("learning_path")
class LearningPath(Page):
    # PageChooserPanel('related_page', 'demo.PublisherPage'),

    content_panels = Page.content_panels + [
        InlinePanel('topics', label="Topics"),
    ]

    subpage_types = ['learnpath.Circle']


    class Meta:
        verbose_name = "Learning Path"

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


class Topic(Orderable):
    title = models.TextField(default='')
    is_visible = models.BooleanField(default=True)

    learning_path = ParentalKey('learnpath.LearningPath',
                                null=True,
                                blank=True,
                                on_delete=models.CASCADE,
                                related_name='topics',
                                )

    panels = [FieldPanel('title'),
              FieldPanel('is_visible'),
              ]

    api_fields = [
        APIField('title'),
        APIField('is_visible'),
    ]


    # content_panels = Page.content_panels + [
    #     FieldPanel('is_visible', classname="full"),
    #     PageChooserPanel('learning_path',  'learnpath.LearningPath'),
    # ]

    # parent_page_types = ['learnpath.LearningPath']
    # subpage_types = ['learnpath.Circle']


    def full_clean(self, *args, **kwargs):
        self.slug = find_available_slug(Topic, slugify(self.title, allow_unicode=True))
        super(Topic, self).full_clean(*args, **kwargs)

    class Meta:
        verbose_name = "Topic"

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


class Circle(Page, Orderable):
    description = models.TextField(default="", blank=True)
    goals = models.TextField(default="", blank=True)
    topic = models.ForeignKey(
        'learnpath.Topic',
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name='circles'
    )

    parent_page_types = ['learnpath.Learningpath']
    subpage_types = ['learnpath.LearningUnit']

    content_panels = Page.content_panels + [
        FieldPanel('description'),
        FieldPanel('goals'),
        InlinePanel('learning_sequences', label="Learning Sequences"),
    ]

    # Export fields over the API
    api_fields = [
        APIField('title'),
        APIField('description'),
        APIField('topic'),
        APIField('content_structure'),
    ]

    @property
    def content_structure(self):
        learning_sequences = LearningSequence.objects.filter(circle_id=self.id).values()
        learning_packages = LearningPackage.objects.filter(learning_sequence__circle_id=self.id).values()
        learning_units = LearningUnit.objects.filter(learning_package__learning_sequence__circle_id=self.id).values('learning_package_id', 'title')

        content = OrderedDict()
        content['learning_sequences'] = []

        for learning_sequence in learning_sequences:
            this_learning_packages = []
            related_learning_packages = [lp for lp in learning_packages if lp['learning_sequence_id'] == learning_sequence['id']]
            for learning_package in related_learning_packages:
                related_learning_units = [lu for lu in learning_units if
                                             lu['learning_package_id'] == learning_package['id']]
                this_learning_units = [learning_unit for learning_unit in related_learning_units]
                learning_package['learning_units'] = this_learning_units
                this_learning_packages.append(learning_package)
            learning_sequence['learning_packages'] = this_learning_packages
            content['learning_sequences'].append(learning_sequence)

        return content




    def full_clean(self, *args, **kwargs):
        self.slug = find_available_slug(Circle, slugify(self.title, allow_unicode=True))
        super(Circle, self).full_clean(*args, **kwargs)

    class Meta:
        verbose_name = "Circle"

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


IN_CIRCLE = 'INCIRCLE'
START = 'START'
END = 'END'

LEARNING_SEQUENCE_CATEGORIES = [
    (IN_CIRCLE, 'In Circle'),
    (START, 'Start'),
    (END, 'End')
]


class LearningSequence(Orderable):
    # TODO: How to do a icon choice field?
    title = models.CharField(max_length=256, default='')
    category = models.CharField(max_length=16, choices=LEARNING_SEQUENCE_CATEGORIES, default=IN_CIRCLE)

    circle = ParentalKey(
        'learnpath.Circle',
        null=True,
        blank=True,
        on_delete=models.CASCADE,
        related_name='learning_sequences',
    )

    panels = [FieldPanel('title'), FieldPanel('category'), FieldPanel('circle')]


    api_fields = [
        APIField('title'),
        APIField('category'),
        APIField('learning_packages'),
    ]



    class Meta:
        verbose_name = "Learning Sequence"

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

    def full_clean(self, *args, **kwargs):
        self.slug = find_available_slug(LearningSequence, slugify(self.title, allow_unicode=True))
        super(LearningSequence, self).full_clean(*args, **kwargs)



class LearningPackage(Orderable):
    title = models.CharField(max_length=256, default='')

    learning_sequence = models.ForeignKey(
        'learnpath.LearningSequence',
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name='learning_packages',
    )
    panels = [FieldPanel('title')]

    api_fields = [
        APIField('title'),
        APIField('my_title'),
    ]

    @property
    def my_title(self):
        return self.title


    def full_clean(self, *args, **kwargs):
        self.slug = find_available_slug(LearningPackage, slugify(self.title, allow_unicode=True))
        super(LearningPackage, self).full_clean(*args, **kwargs)


class LearningUnit(Page, Orderable):
    """
    This is a group of contents, with the übung and test it is one unit. ... more of a structural charactacter.

    """
    # TODO: Review model architecture, is the stream field the right thing here?
    parent_page_types = ['learnpath.Circle']
    learning_package = models.ForeignKey(
        'learnpath.LearningPackage',
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name='learning_units',
    )

    content_blocks = [
        ('web_based_training', WebBasedTrainingBlock()),
        ('video', VideoBlock()),
    ]

    contents = StreamField(StreamBlock(content_blocks),
                           null=True, blank=True, min_num=1, max_num=1)

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

    api_fields = [
        APIField('title'),
        APIField('contents'),
        APIField('content_blocks'),
    ]

    subpage_types = []

    class Meta:
        verbose_name = "Learning Unit"

    def full_clean(self, *args, **kwargs):
        self.slug = find_available_slug(LearningUnit, slugify(self.title, allow_unicode=True))
        super(LearningUnit, self).full_clean(*args, **kwargs)

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



def find_available_slug(model, requested_slug, ignore_page_id=None):
    """
    Finds an available slug within the specified parent.

    If the requested slug is not available, this adds a number on the end, for example:

     - 'requested-slug'
     - 'requested-slug-1'
     - 'requested-slug-2'

    And so on, until an available slug is found.

    The `ignore_page_id` keyword argument is useful for when you are updating a page,
    you can pass the page being updated here so the page's current slug is not
    treated as in use by another page.
    """

    # TODO: In comparison ot wagtails own function, I look for the same model  instead of the parent
    pages = model.objects.filter(slug__startswith=requested_slug)

    if ignore_page_id:
        pages = pages.exclude(id=ignore_page_id)

    existing_slugs = set(pages.values_list("slug", flat=True))
    slug = requested_slug
    number = 1

    while slug in existing_slugs:
        slug = requested_slug + "-" + str(number)
        number += 1

    return slug