core/resolvers/reader.py

import json

from sqlalchemy.orm import aliased
from sqlalchemy.sql.expression import and_, asc, case, desc, func, nulls_last, select

from orm.author import Author
from orm.reaction import Reaction, ReactionKind
from orm.shout import Shout, ShoutAuthor, ShoutTopic
from orm.topic import Topic
from services.db import local_session
from services.schema import query
from services.search import search_text
from services.viewed import ViewedStorage
from utils.logger import root_logger as logger


def has_field(info, fieldname: str) -> bool:
    """
    Проверяет, запрошено ли поле :fieldname: в GraphQL запросе

    :param info: Информация о контексте GraphQL
    :param fieldname: Имя запрашиваемого поля
    :return: True, если поле запрошено, False в противном случае
    """
    field_node = info.field_nodes[0]
    for selection in field_node.selection_set.selections:
        if hasattr(selection, "name") and selection.name.value == fieldname:
            return True
    return False


def query_with_stat(info):
    """
    Добавляет подзапрос статистики

    :param info: Информация о контексте GraphQL
    :return: Запрос с подзапросом статистики.
    """

    q = select(Shout)

    if has_field(info, "stat"):
        stats_subquery = (
            select(
                Reaction.shout,
                func.count(case([(Reaction.kind == ReactionKind.COMMENT.value, 1)], else_=None)).label(
                    "comments_count"
                ),
                func.sum(
                    case(
                        [
                            (Reaction.kind == ReactionKind.LIKE.value, 1),
                            (Reaction.kind == ReactionKind.DISLIKE.value, -1),
                        ],
                        else_=0,
                    )
                ).label("rating"),
                func.max(case([(Reaction.reply_to.is_(None), Reaction.created_at)], else_=None)).label(
                    "last_reacted_at"
                ),
            )
            .where(Reaction.deleted_at.is_(None))
            .group_by(Reaction.shout)
            .subquery()
        )

        q = q.outerjoin(stats_subquery, stats_subquery.c.shout == Shout.id)
        q = q.add_columns(stats_subquery.c.comments_count, stats_subquery.c.rating, stats_subquery.c.last_reacted_at)

    if has_field(info, "created_by"):
        q = q.outerjoin(Author, Shout.created_by == Author.id)
        q = q.add_columns(
            Author.id.label("main_author_id"),
            Author.name.label("main_author_name"),
            Author.slug.label("main_author_slug"),
            Author.pic.label("main_author_pic"),
        )

    if has_field(info, "main_topic"):
        q = q.outerjoin(ShoutTopic, and_(ShoutTopic.shout == Shout.id, ShoutTopic.main.is_(True)))
        q = q.outerjoin(Topic, ShoutTopic.topic == Topic.id)
        q = q.add_columns(
            Topic.id.label("main_topic_id"), Topic.title.label("main_topic_title"), Topic.slug.label("main_topic_slug")
        )

    if has_field(info, "authors"):
        topics_subquery = (
            select(
                ShoutTopic.shout,
                Topic.id.label("topic_id"),
                Topic.title.label("topic_title"),
                Topic.slug.label("topic_slug"),
                ShoutTopic.main.label("is_main"),
            )
            .outerjoin(Topic, ShoutTopic.topic == Topic.id)
            .where(ShoutTopic.shout == Shout.id)
            .subquery()
        )
        q = q.outerjoin(topics_subquery, topics_subquery.c.shout == Shout.id)
        q = q.add_columns(
            topics_subquery.c.topic_id,
            topics_subquery.c.topic_title,
            topics_subquery.c.topic_slug,
            topics_subquery.c.is_main,
        )

        authors_subquery = (
            select(
                ShoutAuthor.shout,
                Author.id.label("author_id"),
                Author.name.label("author_name"),
                Author.slug.label("author_slug"),
                Author.pic.label("author_pic"),
                ShoutAuthor.caption.label("author_caption"),
            )
            .outerjoin(Author, ShoutAuthor.author == Author.id)
            .where(ShoutAuthor.shout == Shout.id)
            .subquery()
        )
        q = q.outerjoin(authors_subquery, authors_subquery.c.shout == Shout.id)
        q = q.add_columns(
            authors_subquery.c.author_id,
            authors_subquery.c.author_name,
            authors_subquery.c.author_slug,
            authors_subquery.c.author_pic,
            authors_subquery.c.author_caption,
        )

    # Фильтр опубликованных
    q = q.where(and_(Shout.published_at.is_not(None), Shout.deleted_at.is_(None)))

    return q


def get_shouts_with_links(info, q, limit=20, offset=0):
    """
    получение публикаций с применением пагинации
    """
    q = q.limit(limit).offset(offset)

    includes_authors = has_field(info, "authors")
    includes_topics = has_field(info, "topics")
    includes_stat = has_field(info, "stat")
    includes_media = has_field(info, "media")

    with local_session() as session:
        shouts_result = session.execute(q).all()
        if not shouts_result:
            return []

        shouts_result = []
        for row in shouts_result:
            logger.debug(row)
            shout_id = row.Shout.id
            shout_dict = row.Shout.dict()
            shout_dict.update(
                {
                    "authors": [],
                    "topics": set(),
                    "media": json.dumps(shout_dict.get("media", [])) if includes_media else [],
                    "stat": {
                        "viewed": ViewedStorage.get_shout(shout_id=shout_id) or 0,
                        "commented": row.comments_count or 0,
                        "rating": row.rating or 0,
                        "last_reacted_at": row.last_reacted_at,
                    }
                    if includes_stat and hasattr(row, "comments_count")
                    else {},
                }
            )
            if includes_authors and hasattr(row, "main_author_id"):
                shout_dict["created_by"] = {
                    "id": row.main_author_id,
                    "name": row.main_author_name or "Аноним",
                    "slug": row.main_author_slug or "",
                    "pic": row.main_author_pic or "",
                }
            if includes_topics and hasattr(row, "main_topic_id"):
                shout_dict["main_topic"] = {
                    "id": row.main_topic_id or 0,
                    "title": row.main_topic_title or "",
                    "slug": row.main_topic_slug or "",
                }

            if includes_authors and hasattr(row, "author_id"):
                author = {
                    "id": row.author_id,
                    "name": row.author_name,
                    "slug": row.author_slug,
                    "pic": row.author_pic,
                    "caption": row.author_caption,
                }
                if not filter(lambda x: x["id"] == author["id"], shout_dict["authors"]):
                    shout_dict["authors"].append(author)

            if includes_topics and hasattr(row, "topic_id"):
                topic = {
                    "id": row.topic_id,
                    "title": row.topic_title,
                    "slug": row.topic_slug,
                    "is_main": row.is_main,
                }
                if not filter(lambda x: x["id"] == topic["id"], shout_dict["topics"]):
                    shout_dict["topics"].add(frozenset(topic.items()))

            if includes_topics:
                shout_dict["topics"] = sorted(
                    [dict(t) for t in shout_dict["topics"]], key=lambda x: (not x.get("is_main", False), x["id"])
                )

        return shouts_result


def apply_filters(q, filters):
    """
    Применение общих фильтров к запросу.

    :param q: Исходный запрос.
    :param filters: Словарь фильтров.
    :return: Запрос с примененными фильтрами.
    """
    if isinstance(filters, dict):
        if "featured" in filters:
            featured_filter = filters.get("featured")
            if featured_filter:
                q = q.filter(Shout.featured_at.is_not(None))
            else:
                q = q.filter(Shout.featured_at.is_(None))
        by_layouts = filters.get("layouts")
        if by_layouts and isinstance(by_layouts, list):
            q = q.filter(Shout.layout.in_(by_layouts))
        by_author = filters.get("author")
        if by_author:
            q = q.filter(Shout.authors.any(slug=by_author))
        by_topic = filters.get("topic")
        if by_topic:
            q = q.filter(Shout.topics.any(slug=by_topic))
        by_after = filters.get("after")
        if by_after:
            ts = int(by_after)
            q = q.filter(Shout.created_at > ts)

    return q


@query.field("get_shout")
async def get_shout(_, info, slug="", shout_id=0):
    """
    Получение публикации по slug или id.

    :param _: Корневой объект запроса (не используется)
    :param info: Информация о контексте GraphQL
    :param slug: Уникальный идентификатор публикации
    :param shout_id: ID публикации
    :return: Данные публикации с включенной статистикой
    """
    try:
        # Получаем базовый запрос с подзапросами статистики
        q = query_with_stat(info)

        # Применяем фильтр по slug или id
        if slug:
            q = q.where(Shout.slug == slug)
        elif shout_id:
            q = q.where(Shout.id == shout_id)
        else:
            return None

        # Получаем результат через get_shouts_with_stats с limit=1
        shouts = get_shouts_with_links(info, q, limit=1)

        # Возвращаем первую (и единственную) публикацию, если она найдена
        return shouts[0] if shouts else None

    except Exception as exc:
        logger.error(f"Error in get_shout: {exc}", exc_info=True)
        return None


def apply_sorting(q, options):
    """
    Применение сортировки к запросу.

    :param q: Исходный запрос.
    :param options: Опции фильтрации и сортировки.
    :return: Запрос с примененной сортировкой.
    """
    # Определение поля для сортировки
    order_str = options.get("order_by")

    # Проверка, требуется ли сортировка по одному из статистических полей
    if order_str in ["rating", "comments_count", "last_reacted_at"]:
        # Сортировка по выбранному статистическому полю в указанном порядке
        q = q.order_by(desc(order_str))
        query_order_by = desc(order_str) if options.get("order_by_desc", True) else asc(order_str)
        # Применение сортировки с размещением NULL значений в конце
        q = q.order_by(nulls_last(query_order_by))
    else:
        q = q.order_by(Shout.published_at.desc())

    return q


@query.field("load_shouts_by")
async def load_shouts_by(_, info, options):
    """
    Загрузка публикаций с фильтрацией, сортировкой и пагинацией.

    :param _: Корневой объект запроса (не используется)
    :param info: Информация о контексте GraphQL
    :param options: Опции фильтрации и сортировки.
    :return: Список публикаций, удовлетворяющих критериям.
    """
    # Базовый запрос: если запрашиваются статистические данные, используем специальный запрос с статистикой
    q = query_with_stat(info)

    filters = options.get("filters")
    if isinstance(filters, dict):
        q = apply_filters(q, filters)

    q = apply_sorting(q, options)

    # Установка лимита и смещения для пагинации
    offset = options.get("offset", 0)
    limit = options.get("limit", 10)

    # Передача сформированного запроса в метод получения публикаций с учетом сортировки и пагинации
    return get_shouts_with_links(info, q, limit, offset)


@query.field("load_shouts_search")
async def load_shouts_search(_, info, text, options):
    """
    Поиск публикаций по тексту.

    :param _: Корневой объект запроса (не используется)
    :param info: Информация о контексте GraphQL
    :param text: Строка поиска.
    :param options: Опции фильтрации и сортировки.
    :return: Список публикаций, найденных по тексту.
    """
    limit = options.get("limit", 10)
    offset = options.get("offset", 0)
    if isinstance(text, str) and len(text) > 2:
        results = await search_text(text, limit, offset)
        scores = {}
        hits_ids = []
        for sr in results:
            shout_id = sr.get("id")
            if shout_id:
                shout_id = str(shout_id)
                scores[shout_id] = sr.get("score")
                hits_ids.append(shout_id)

        q = (
            query_with_stat(info)
            if has_field(info, "stat")
            else select(Shout).filter(and_(Shout.published_at.is_not(None), Shout.deleted_at.is_(None)))
        )
        q = q.filter(Shout.id.in_(hits_ids))
        q = apply_filters(q, options)
        q = apply_sorting(q, options)
        shouts = get_shouts_with_links(info, q, limit, offset)
        for shout in shouts:
            shout.score = scores[f"{shout.id}"]
        shouts.sort(key=lambda x: x.score, reverse=True)
        return shouts
    return []


@query.field("load_shouts_unrated")
async def load_shouts_unrated(_, info, options):
    """
    Загрузка публикаций с менее чем 3 реакциями типа LIKE/DISLIKE

    :param _: Корневой объект запроса (не используется)
    :param info: Информация о контексте GraphQL
    :param options: Опции фильтрации и сортировки.
    :return: Список публикаций.
    """
    rated_shouts = (
        select(Reaction.shout)
        .where(
            and_(
                Reaction.deleted_at.is_(None), Reaction.kind.in_([ReactionKind.LIKE.value, ReactionKind.DISLIKE.value])
            )
        )
        .group_by(Reaction.shout)
        .having(func.count("*") >= 3)
        .scalar_subquery()
    )

    q = (
        select(Shout)
        .where(and_(Shout.published_at.is_not(None), Shout.deleted_at.is_(None), ~Shout.id.in_(rated_shouts)))
        # .order_by(desc(Shout.published_at))
        .order_by(func.random())
    )
    limit = options.get("limit", 5)
    offset = options.get("offset", 0)
    return get_shouts_with_links(info, q, limit, offset)


@query.field("load_shouts_random_top")
async def load_shouts_random_top(_, info, options):
    """
    Загрузка случайных публикаций, упорядоченных по топовым реакциям.

    :param _info: Информация о контексте GraphQL.
    :param options: Опции фильтрации и сортировки.
    :return: Список случайных публикаций.
    """
    aliased_reaction = aliased(Reaction)

    subquery = select(Shout.id).outerjoin(aliased_reaction).where(Shout.deleted_at.is_(None))

    filters = options.get("filters")
    if isinstance(filters, dict):
        subquery = apply_filters(subquery, filters)

    subquery = subquery.group_by(Shout.id).order_by(
        desc(
            func.sum(
                case(
                    # не учитывать реакции на комментарии
                    (aliased_reaction.reply_to.is_not(None), 0),
                    (aliased_reaction.kind == ReactionKind.LIKE.value, 1),
                    (aliased_reaction.kind == ReactionKind.DISLIKE.value, -1),
                    else_=0,
                )
            )
        )
    )

    random_limit = options.get("random_limit", 100)
    if random_limit:
        subquery = subquery.limit(random_limit)
    q = (
        query_with_stat(info)
        if has_field(info, "stat")
        else select(Shout).filter(and_(Shout.published_at.is_not(None), Shout.deleted_at.is_(None)))
    )
    q = q.filter(Shout.id.in_(subquery))
    q = q.order_by(func.random())
    limit = options.get("limit", 10)
    return get_shouts_with_links(info, q, limit)