import logging
from datetime import datetime, timezone

from fastapi import APIRouter, Depends, Request
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.database import get_db
from app.models import Subscription
from app.schemas import SubscribeRequest, SubscribeResponse
from app.services.signed_request import verify_signed_request

router = APIRouter()
logger = logging.getLogger(__name__)

ACTION_SUBSCRIBE = "subscribe"


@router.post("/subscribe", response_model=SubscribeResponse)
async def subscribe(request: Request, db: AsyncSession = Depends(get_db)):
    """Activate a subscription. Optional `paper_mode` flag in the body lets
    new users try the system safely (no Hyperliquid call, simulated fills).

    Signed message body is the RAW dict so the canonical hash matches what
    the frontend signed — same pattern as set_user_settings.
    """
    raw = await request.json()
    body = SubscribeRequest(**raw)
    wallet = body.wallet.lower().strip()

    # The signed body excludes the envelope fields. For backwards compatibility
    # with old clients that signed `body=None` (no paper_mode key), accept
    # either signature.
    paper_mode = bool(raw.get("paper_mode", False))
    signed_body = {"paper_mode": paper_mode} if paper_mode else None

    verify_signed_request(
        action=ACTION_SUBSCRIBE,
        wallet=wallet,
        timestamp_ms=body.timestamp,
        signature=body.signature,
        body=signed_body,
    )

    result = await db.execute(
        select(Subscription).where(Subscription.wallet_address == wallet)
    )
    sub = result.scalar_one_or_none()
    now = datetime.now(timezone.utc).replace(tzinfo=None)

    if sub is None:
        sub = Subscription(
            wallet_address=wallet,
            active=True,
            subscribed_at=now,
            paper_mode=paper_mode,
        )
        db.add(sub)
    else:
        sub.active = True
        if sub.subscribed_at is None:
            sub.subscribed_at = now
        # Re-subscribing is allowed to change paper mode (e.g. user wants to
        # promote from paper to live). Otherwise leave existing flag alone.
        if paper_mode != sub.paper_mode:
            sub.paper_mode = paper_mode

    await db.commit()
    logger.info("Subscription activated for %s (paper_mode=%s)", wallet, paper_mode)
    return SubscribeResponse(status="ok", wallet=wallet, paper_mode=paper_mode)