from typing import Union

from fastapi import HTTPException, status

from app.models import Author as AuthorDB
from app.models import Book as BookDB
from app.serializers.book import CreateBook, CreateRemoteBook
from app.services.common import (
    TRGMSearchService,
    MeiliSearchService,
    GetRandomService,
    BaseFilterService,
)


GET_OBJECT_IDS_QUERY = """
SELECT ARRAY(
    WITH filtered_books AS (
        SELECT id, similarity(title, :query) as sml FROM books
        WHERE books.title % :query AND books.is_deleted = 'f'
              AND books.lang = ANY(:langs ::text[])
    )
    SELECT fbooks.id FROM filtered_books as fbooks
    ORDER BY fbooks.sml DESC, fbooks.id
    LIMIT 210
);
"""


class BookTGRMSearchService(TRGMSearchService):
    MODEL_CLASS = BookDB
    PREFETCH_RELATED = ["source"]
    SELECT_RELATED = ["authors", "translators", "annotations"]
    GET_OBJECT_IDS_QUERY = GET_OBJECT_IDS_QUERY


class BookFilterService(BaseFilterService):
    MODEL_CLASS = BookDB
    PREFETCH_RELATED = ["source"]
    SELECT_RELATED = ["authors", "translators", "annotations"]


class BookCreator:
    @classmethod
    def _raise_bad_request(cls):
        raise HTTPException(status.HTTP_404_NOT_FOUND)

    @classmethod
    async def _create_book(cls, data: CreateBook) -> BookDB:
        data_dict = data.dict()

        author_ids = data_dict.pop("authors", [])
        authors = await AuthorDB.objects.filter(id__in=author_ids).all()

        if len(author_ids) != len(authors):
            cls._raise_bad_request()

        book = await BookDB.objects.create(**data_dict)

        for author in authors:
            await book.authors.add(author)

        return book

    @classmethod
    async def _create_remote_book(cls, data: CreateRemoteBook) -> BookDB:
        data_dict = data.dict()

        author_ids = data_dict.pop("remote_authors", [])
        authors = await AuthorDB.objects.filter(
            source__id=data.source, remote_id__in=author_ids
        ).all()

        if len(author_ids) != len(authors):
            cls._raise_bad_request()

        book = await BookDB.objects.create(**data_dict)

        for author in authors:
            await book.authors.add(author)

        return book

    @classmethod
    async def create(cls, data: Union[CreateBook, CreateRemoteBook]) -> BookDB:
        if isinstance(data, CreateBook):
            return await cls._create_book(data)
        if isinstance(data, CreateRemoteBook):
            return await cls._create_remote_book(data)


GET_OBJECTS_ID_QUERY = """
WITH filtered_books AS (
    SELECT id FROM books
    WHERE books.is_deleted = 'f' AND books.lang = ANY(:langs ::text[])
)
SELECT id FROM filtered_books;
"""


class GetRandomBookService(GetRandomService):
    MODEL_CLASS = BookDB
    GET_OBJECTS_ID_QUERY = GET_OBJECTS_ID_QUERY


class BookMeiliSearchService(MeiliSearchService):
    MODEL_CLASS = BookDB
    PREFETCH_RELATED = ["source"]
    SELECT_RELATED = ["authors", "translators", "annotations"]

    MS_INDEX_NAME = "books"
    MS_INDEX_LANG_KEY = "lang"