import abc
from typing import List

from auto_labeling_pipeline.labels import Labels
from django.contrib.auth.models import User

from api.models import Project
from examples.models import Example
from label_types.models import CategoryType, SpanType
from labels.models import Label, Category, Span, TextLabel


class LabelCollection(abc.ABC):
    label_type = None
    model = None

    def __init__(self, labels):
        self.labels = labels

    def transform(self, project: Project, example: Example, user: User) -> List[Label]:
        mapping = {
            c.text: c for c in self.label_type.objects.filter(project=project)
        }
        annotations = []
        for label in self.labels:
            if label['label'] not in mapping:
                continue
            label['example'] = example
            label['label'] = mapping[label['label']]
            label['user'] = user
            annotations.append(self.model(**label))
        return annotations

    def save(self, project: Project, example: Example, user: User):
        labels = self.transform(project, example, user)
        labels = self.model.objects.filter_annotatable_labels(labels, project)
        self.model.objects.bulk_create(labels)


class Categories(LabelCollection):
    label_type = CategoryType
    model = Category


class Spans(LabelCollection):
    label_type = SpanType
    model = Span


class Texts(LabelCollection):
    model = TextLabel

    def transform(self, project: Project, example: Example, user: User) -> List[Label]:
        annotations = []
        for label in self.labels:
            label['example'] = example
            label['user'] = user
            annotations.append(self.model(**label))
        return annotations


def create_labels(task_type: str, labels: Labels) -> LabelCollection:
    return {
        'Category': Categories,
        'Span': Spans,
        'Text': Texts
    }[task_type](labels.dict())