"""Guest Auth routes — login, logout for guest users."""

from __future__ import annotations

import uuid
from datetime import UTC, datetime, timedelta

from fastapi import APIRouter, Depends, HTTPException, Request, Response, status
from pydantic import BaseModel, EmailStr
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.config import get_settings
from app.core.auth import get_redis, hash_password, verify_password
from app.core.db import get_db
from app.deps import get_current_guest
from app.models.guest_user import GuestUser
from app.models.tenant import Tenant

router = APIRouter(prefix="/api/v1/guest", tags=["guest-auth"])
settings = get_settings()


class GuestLoginRequest(BaseModel):
    """Schema for guest login request."""
    email: EmailStr
    password: str
    tenant_slug: str


@router.post("/login")
async def guest_login(
    request: Request,
    body: GuestLoginRequest,
    db: AsyncSession = Depends(get_db),
):
    """Guest login with email+password. Sets guest session cookie."""
    email = body.email
    password = body.password
    tenant_slug = body.tenant_slug

    # Find guest user by email — tenant_slug is required to prevent cross-tenant enumeration
    tenant_q = await db.execute(
        select(Tenant).where(Tenant.slug == tenant_slug)
    )
    tenant = tenant_q.scalar_one_or_none()
    if not tenant:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail={"detail": "Invalid credentials", "code": "invalid_credentials"},
        )
    tenant_id = tenant.id

    # Find guest with tenant context
    guest_q = await db.execute(
        select(GuestUser)
        .where(GuestUser.email == email)
        .where(GuestUser.tenant_id == tenant_id)
        .where(GuestUser.status == "active")
    )
    guest = guest_q.scalar_one_or_none()

    if not guest or not guest.password_hash:
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail={"detail": "Invalid credentials", "code": "invalid_credentials"},
        )

    if not verify_password(password, guest.password_hash):
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail={"detail": "Invalid credentials", "code": "invalid_credentials"},
        )

    # Check expiration
    if guest.expires_at and guest.expires_at < datetime.now(UTC):
        guest.status = "expired"
        await db.commit()
        raise HTTPException(
            status_code=status.HTTP_401_UNAUTHORIZED,
            detail={"detail": "Guest access expired", "code": "guest_expired"},
        )

    # Create guest session in Redis
    redis = get_redis()
    session_id = str(uuid.uuid4())
    csrf_token = str(uuid.uuid4())
    session_data = {
        "guest_user_id": str(guest.id),
        "tenant_id": str(tenant_id),
        "email": guest.email,
        "name": guest.name,
        "csrf_token": csrf_token,
        "is_guest": True,
    }
    import json

    await redis.setex(
        f"guest_session:{session_id}",
        1800,  # 30 min TTL
        json.dumps(session_data),
    )
    # Track session in guest index for revocation (P1.6 fix)
    await redis.sadd(f"guest_sessions:{guest.id}", session_id)
    await redis.expire(f"guest_sessions:{guest.id}", 1800)

    from fastapi.responses import JSONResponse

    resp = JSONResponse(
        status_code=status.HTTP_200_OK,
        content={
            "guest_user_id": str(guest.id),
            "email": guest.email,
            "name": guest.name,
            "tenant_id": str(tenant_id),
            "csrf_token": csrf_token,
        },
    )
    resp.set_cookie(
        key="guest_session",
        value=session_id,
        httponly=True,
        secure=settings.session_cookie_secure,
        samesite=settings.session_cookie_samesite,
        max_age=1800,
        path="/",
    )
    return resp


@router.post("/logout")
async def guest_logout(
    request: Request,
):
    """Logout — invalidate guest session, clear cookie."""
    session_id = request.cookies.get("guest_session")
    if session_id:
        redis = get_redis()
        # Remove from guest sessions index (P1.6 fix)
        guest_data = await redis.get(f"guest_session:{session_id}")
        if guest_data:
            import json
            data = json.loads(guest_data)
            gid = data.get("guest_user_id")
            if gid:
                await redis.srem(f"guest_sessions:{gid}", session_id)
        await redis.delete(f"guest_session:{session_id}")

    from fastapi.responses import JSONResponse

    resp = JSONResponse(
        status_code=status.HTTP_200_OK,
        content={"message": "Logged out"},
    )
    resp.delete_cookie("guest_session", path="/")
    return resp


@router.get("/me")
async def guest_me(
    current_guest: dict = Depends(get_current_guest),
):
    """Get current guest user info."""
    return {
        "guest_user_id": current_guest.get("guest_user_id"),
        "email": current_guest.get("email"),
        "name": current_guest.get("name"),
        "tenant_id": current_guest.get("tenant_id"),
    }