import django_filters

from .models import (
    Article,
    Magazine,
    MagazineCategory,
    Organize,
    OrganizeCategory,
    Professor,
    Subject,
    WorkGroup,
    WorkGroupTerm,
)


class NumberInFilter(django_filters.BaseInFilter, django_filters.NumberFilter):
    """支持 ?year=2023,2024 或多值 in 查询。"""


class ArticleFilter(django_filters.FilterSet):
    type = NumberInFilter(field_name="type")
    year = NumberInFilter(field_name="year")
    year_gte = django_filters.NumberFilter(field_name="year", lookup_expr="gte")
    year_lte = django_filters.NumberFilter(field_name="year", lookup_expr="lte")
    organize = NumberInFilter(field_name="organizes")
    magazine = NumberInFilter(field_name="magazines")
    subject = NumberInFilter(field_name="subjects")
    search = django_filters.CharFilter(field_name="title", lookup_expr="icontains")
    ordering = django_filters.OrderingFilter(
        fields=(
            ("score", "score"),
            ("year", "year"),
            ("rank", "rank"),
            ("push_date", "push_date"),
            ("created_at", "created_at"),
        )
    )

    class Meta:
        model = Article
        fields = ["type", "year", "is_disabled"]


class OrganizeFilter(django_filters.FilterSet):
    search = django_filters.CharFilter(field_name="name", lookup_expr="icontains")
    category = django_filters.NumberFilter(field_name="category_id")

    class Meta:
        model = Organize
        fields = ["category", "is_disabled"]


class MagazineFilter(django_filters.FilterSet):
    search = django_filters.CharFilter(field_name="name", lookup_expr="icontains")
    subject = django_filters.NumberFilter(field_name="subjects")
    category = django_filters.NumberFilter(field_name="category_id")

    class Meta:
        model = Magazine
        fields = ["category", "is_disabled"]


class ProfessorFilter(django_filters.FilterSet):
    search = django_filters.CharFilter(field_name="name", lookup_expr="icontains")
    term = django_filters.NumberFilter(method="filter_term_tree")
    workgroup = django_filters.NumberFilter(field_name="terms__workgroup")

    class Meta:
        model = Professor
        fields = ["type", "is_disabled"]

    def filter_term_tree(self, queryset, name, value):
        """包含该届及其同届下级分委会。"""
        ids = {int(value)}
        frontier = [int(value)]
        while frontier:
            children = list(
                WorkGroupTerm.objects.filter(parent_id__in=frontier).values_list(
                    "id", flat=True
                )
            )
            frontier = [cid for cid in children if cid not in ids]
            ids.update(frontier)
        return queryset.filter(terms__in=ids).distinct()


class WorkGroupFilter(django_filters.FilterSet):
    class Meta:
        model = WorkGroup
        fields = ["parent", "is_disabled"]


class WorkGroupTermFilter(django_filters.FilterSet):
    class Meta:
        model = WorkGroupTerm
        fields = ["workgroup", "parent", "is_current", "is_disabled"]


class SubjectFilter(django_filters.FilterSet):
    class Meta:
        model = Subject
        fields = ["parent", "is_disabled"]


class OrganizeCategoryFilter(django_filters.FilterSet):
    class Meta:
        model = OrganizeCategory
        fields = ["parent", "is_disabled"]


class MagazineCategoryFilter(django_filters.FilterSet):
    class Meta:
        model = MagazineCategory
        fields = ["parent", "is_disabled"]