from datetime import datetime
from typing import ClassVar, NotRequired, TypedDict

from app.models.room import (
    MatchType,
    QueueMode,
    RoomCategory,
    RoomDifficultyRange,
    RoomPlaylistItemStats,
    RoomStatus,
)
from app.utils import utcnow

from ._base import DatabaseModel, included, ondemand
from .item_attempts_count import ItemAttemptsCount, ItemAttemptsCountDict, ItemAttemptsCountModel
from .playlists import Playlist, PlaylistDict, PlaylistModel
from .room_participated_user import RoomParticipatedUser
from .user import User, UserDict, UserModel

from pydantic import field_validator
from sqlalchemy.ext.asyncio import AsyncAttrs
from sqlmodel import BigInteger, Column, DateTime, Field, ForeignKey, Relationship, SQLModel, col, select
from sqlmodel.ext.asyncio.session import AsyncSession


class RoomDict(TypedDict):
    id: int
    name: str
    category: RoomCategory
    status: RoomStatus
    type: MatchType
    duration: int | None
    starts_at: datetime | None
    ends_at: datetime | None
    max_attempts: int | None
    participant_count: int
    channel_id: int
    queue_mode: QueueMode
    auto_skip: bool
    auto_start_duration: int
    has_password: NotRequired[bool]
    current_playlist_item: NotRequired["PlaylistDict | None"]
    playlist: NotRequired[list["PlaylistDict"]]
    playlist_item_stats: NotRequired[RoomPlaylistItemStats]
    difficulty_range: NotRequired[RoomDifficultyRange]
    host: NotRequired[UserDict]
    recent_participants: NotRequired[list[UserDict]]
    current_user_score: NotRequired["ItemAttemptsCountDict | None"]


class RoomModel(DatabaseModel[RoomDict]):
    SHOW_RESPONSE_INCLUDES: ClassVar[list[str]] = [
        "current_user_score.playlist_item_attempts",
        "host.country",
        "playlist.beatmap.beatmapset",
        "playlist.beatmap.checksum",
        "playlist.beatmap.max_combo",
        "recent_participants",
    ]

    id: int = Field(default=None, primary_key=True, index=True)
    name: str = Field(index=True)
    category: RoomCategory = Field(default=RoomCategory.NORMAL, index=True)
    status: RoomStatus
    type: MatchType
    duration: int | None = Field(default=None)  # minutes
    starts_at: datetime | None = Field(
        sa_column=Column(
            DateTime(timezone=True),
        ),
        default_factory=utcnow,
    )
    ends_at: datetime | None = Field(
        sa_column=Column(
            DateTime(timezone=True),
        ),
        default=None,
    )
    max_attempts: int | None = Field(default=None)  # playlists
    participant_count: int = Field(default=0)
    channel_id: int = 0
    queue_mode: QueueMode
    auto_skip: bool

    auto_start_duration: int

    @field_validator("channel_id", mode="before")
    @classmethod
    def validate_channel_id(cls, v):
        """将 None 转换为 0"""
        if v is None:
            return 0
        return v

    @included
    @staticmethod
    async def has_password(_session: AsyncSession, room: "Room") -> bool:
        return bool(room.password)

    @ondemand
    @staticmethod
    async def current_playlist_item(
        _session: AsyncSession, room: "Room", includes: list[str] | None = None
    ) -> "PlaylistDict | None":
        playlists = await room.awaitable_attrs.playlist
        if not playlists:
            return None
        return await PlaylistModel.transform(playlists[-1], includes=includes)

    @ondemand
    @staticmethod
    async def playlist(_session: AsyncSession, room: "Room", includes: list[str] | None = None) -> list["PlaylistDict"]:
        playlists = await room.awaitable_attrs.playlist
        result: list[PlaylistDict] = []
        for playlist_item in playlists:
            result.append(await PlaylistModel.transform(playlist_item, includes=includes))
        return result

    @ondemand
    @staticmethod
    async def playlist_item_stats(_session: AsyncSession, room: "Room") -> RoomPlaylistItemStats:
        playlists = await room.awaitable_attrs.playlist
        stats = RoomPlaylistItemStats(count_active=0, count_total=0, ruleset_ids=[])
        rulesets: set[int] = set()
        for playlist in playlists:
            stats.count_total += 1
            if not playlist.expired:
                stats.count_active += 1
            rulesets.add(playlist.ruleset_id)
        stats.ruleset_ids = list(rulesets)
        return stats

    @ondemand
    @staticmethod
    async def difficulty_range(_session: AsyncSession, room: "Room") -> RoomDifficultyRange:
        playlists = await room.awaitable_attrs.playlist
        if not playlists:
            return RoomDifficultyRange(min=0.0, max=0.0)
        min_diff = float("inf")
        max_diff = float("-inf")
        for playlist in playlists:
            rating = playlist.beatmap.difficulty_rating
            min_diff = min(min_diff, rating)
            max_diff = max(max_diff, rating)
        if min_diff == float("inf"):
            min_diff = 0.0
        if max_diff == float("-inf"):
            max_diff = 0.0
        return RoomDifficultyRange(min=min_diff, max=max_diff)

    @ondemand
    @staticmethod
    async def host(_session: AsyncSession, room: "Room", includes: list[str] | None = None) -> UserDict:
        host_user = await room.awaitable_attrs.host
        return await UserModel.transform(host_user, includes=includes)

    @ondemand
    @staticmethod
    async def recent_participants(session: AsyncSession, room: "Room") -> list[UserDict]:
        participants: list[UserDict] = []
        if room.category == RoomCategory.REALTIME:
            query = (
                select(RoomParticipatedUser)
                .where(
                    RoomParticipatedUser.room_id == room.id,
                    col(RoomParticipatedUser.left_at).is_(None),
                )
                .limit(8)
                .order_by(col(RoomParticipatedUser.joined_at).desc())
            )
        else:
            query = (
                select(RoomParticipatedUser)
                .where(
                    RoomParticipatedUser.room_id == room.id,
                )
                .limit(8)
                .order_by(col(RoomParticipatedUser.joined_at).desc())
            )
        for recent_participant in await session.exec(query):
            user_instance = await recent_participant.awaitable_attrs.user
            participants.append(await UserModel.transform(user_instance))
        return participants

    @ondemand
    @staticmethod
    async def current_user_score(
        session: AsyncSession, room: "Room", includes: list[str] | None = None
    ) -> "ItemAttemptsCountDict | None":
        item_attempt = (
            await session.exec(
                select(ItemAttemptsCount).where(
                    ItemAttemptsCount.room_id == room.id,
                )
            )
        ).first()
        if item_attempt is None:
            return None

        return await ItemAttemptsCountModel.transform(item_attempt, includes=includes)


class Room(AsyncAttrs, RoomModel, table=True):
    __tablename__: str = "rooms"

    host_id: int = Field(sa_column=Column(BigInteger, ForeignKey("lazer_users.id"), index=True))
    password: str | None = Field(default=None)

    host: User = Relationship()
    playlist: list[Playlist] = Relationship(
        sa_relationship_kwargs={
            "lazy": "selectin",
            "cascade": "all, delete-orphan",
            "overlaps": "room",
        }
    )


class APIUploadedRoom(SQLModel):
    name: str = Field(index=True)
    category: RoomCategory = Field(default=RoomCategory.NORMAL, index=True)
    status: RoomStatus
    type: MatchType
    duration: int | None = Field(default=None)  # minutes
    starts_at: datetime | None = Field(
        sa_column=Column(
            DateTime(timezone=True),
        ),
        default_factory=utcnow,
    )
    ends_at: datetime | None = Field(
        sa_column=Column(
            DateTime(timezone=True),
        ),
        default=None,
    )
    max_attempts: int | None = Field(default=None)  # playlists
    participant_count: int = Field(default=0)
    channel_id: int = 0
    queue_mode: QueueMode
    auto_skip: bool
    auto_start_duration: int
    playlist: list[Playlist] = Field(default_factory=list)