from __future__ import annotations

from app.database import ChatMessageResp
from app.database.chat import (
    ChannelType,
    ChatChannel,
    ChatChannelResp,
    ChatMessage,
    MessageType,
    SilenceUser,
    UserSilenceResp,
)
from app.database.lazer_user import User
from app.dependencies.database import get_db, get_redis
from app.dependencies.param import BodyOrForm
from app.dependencies.user import get_current_user
from app.router.v2 import api_v2_router as router

from .banchobot import bot
from .server import server

from fastapi import Depends, HTTPException, Query, Security
from pydantic import BaseModel, Field
from redis.asyncio import Redis
from sqlmodel import col, select
from sqlmodel.ext.asyncio.session import AsyncSession


class KeepAliveResp(BaseModel):
    silences: list[UserSilenceResp] = Field(default_factory=list)


@router.post("/chat/ack")
async def keep_alive(
    history_since: int | None = Query(None),
    since: int | None = Query(None),
    current_user: User = Security(get_current_user, scopes=["chat.read"]),
    session: AsyncSession = Depends(get_db),
):
    resp = KeepAliveResp()
    if history_since:
        silences = (
            await session.exec(
                select(SilenceUser).where(col(SilenceUser.id) > history_since)
            )
        ).all()
        resp.silences.extend([UserSilenceResp.from_db(silence) for silence in silences])
    elif since:
        msg = await session.get(ChatMessage, since)
        if msg:
            silences = (
                await session.exec(
                    select(SilenceUser).where(
                        col(SilenceUser.banned_at) > msg.timestamp
                    )
                )
            ).all()
            resp.silences.extend(
                [UserSilenceResp.from_db(silence) for silence in silences]
            )

    return resp


class MessageReq(BaseModel):
    message: str
    is_action: bool = False
    uuid: str | None = None


@router.post("/chat/channels/{channel}/messages", response_model=ChatMessageResp)
async def send_message(
    channel: str,
    req: MessageReq = Depends(BodyOrForm(MessageReq)),
    current_user: User = Security(get_current_user, scopes=["chat.write"]),
    session: AsyncSession = Depends(get_db),
):
    db_channel = await ChatChannel.get(channel, session)
    if db_channel is None:
        raise HTTPException(status_code=404, detail="Channel not found")

    assert db_channel.channel_id
    assert current_user.id
    msg = ChatMessage(
        channel_id=db_channel.channel_id,
        content=req.message,
        sender_id=current_user.id,
        type=MessageType.ACTION if req.is_action else MessageType.PLAIN,
        uuid=req.uuid,
    )
    session.add(msg)
    await session.commit()
    await session.refresh(msg)
    await session.refresh(current_user)
    await session.refresh(db_channel)
    resp = await ChatMessageResp.from_db(msg, session, current_user)
    is_bot_command = req.message.startswith("!")
    await server.send_message_to_channel(
        resp, is_bot_command and db_channel.type == ChannelType.PUBLIC
    )
    if is_bot_command:
        await bot.try_handle(current_user, db_channel, req.message, session)
    return resp


@router.get("/chat/channels/{channel}/messages", response_model=list[ChatMessageResp])
async def get_message(
    channel: str,
    limit: int = Query(50, ge=1, le=50),
    since: int = Query(default=0, ge=0),
    until: int | None = Query(None),
    current_user: User = Security(get_current_user, scopes=["chat.read"]),
    session: AsyncSession = Depends(get_db),
):
    db_channel = await ChatChannel.get(channel, session)
    if db_channel is None:
        raise HTTPException(status_code=404, detail="Channel not found")
    messages = await session.exec(
        select(ChatMessage)
        .where(
            ChatMessage.channel_id == db_channel.channel_id,
            col(ChatMessage.message_id) > since,
            col(ChatMessage.message_id) < until if until is not None else True,
        )
        .order_by(col(ChatMessage.timestamp).desc())
        .limit(limit)
    )
    resp = [await ChatMessageResp.from_db(msg, session) for msg in messages]
    resp.reverse()
    return resp


@router.put("/chat/channels/{channel}/mark-as-read/{message}", status_code=204)
async def mark_as_read(
    channel: str,
    message: int,
    current_user: User = Security(get_current_user, scopes=["chat.read"]),
    session: AsyncSession = Depends(get_db),
):
    db_channel = await ChatChannel.get(channel, session)
    if db_channel is None:
        raise HTTPException(status_code=404, detail="Channel not found")
    assert db_channel.channel_id
    await server.mark_as_read(db_channel.channel_id, message)


class PMReq(BaseModel):
    target_id: int
    message: str
    is_action: bool = False
    uuid: str | None = None


class NewPMResp(BaseModel):
    channel: ChatChannelResp
    message: ChatMessageResp
    new_channel_id: int


@router.post("/chat/new")
async def create_new_pm(
    req: PMReq = Depends(BodyOrForm(PMReq)),
    current_user: User = Security(get_current_user, scopes=["chat.write"]),
    session: AsyncSession = Depends(get_db),
    redis: Redis = Depends(get_redis),
):
    user_id = current_user.id
    target = await session.get(User, req.target_id)
    if target is None:
        raise HTTPException(status_code=404, detail="Target user not found")
    is_can_pm, block = await target.is_user_can_pm(current_user, session)
    if not is_can_pm:
        raise HTTPException(status_code=403, detail=block)

    assert user_id
    channel = await ChatChannel.get_pm_channel(user_id, req.target_id, session)
    if channel is None:
        channel = ChatChannel(
            name=f"pm_{user_id}_{req.target_id}",
            description="Private message channel",
            type=ChannelType.PM,
        )
        session.add(channel)
        await session.commit()
        await session.refresh(channel)
        await session.refresh(target)
        await session.refresh(current_user)

    assert channel.channel_id
    await server.batch_join_channel([target, current_user], channel, session)
    channel_resp = await ChatChannelResp.from_db(
        channel, session, current_user, redis, server.channels[channel.channel_id]
    )
    msg = ChatMessage(
        channel_id=channel.channel_id,
        content=req.message,
        sender_id=user_id,
        type=MessageType.ACTION if req.is_action else MessageType.PLAIN,
        uuid=req.uuid,
    )
    session.add(msg)
    await session.commit()
    await session.refresh(msg)
    await session.refresh(current_user)
    await session.refresh(channel)
    message_resp = await ChatMessageResp.from_db(msg, session, current_user)
    await server.send_message_to_channel(message_resp)
    return NewPMResp(
        channel=channel_resp,
        message=message_resp,
        new_channel_id=channel_resp.channel_id,
    )