"""FastAPI entrypoint. Runs Alembic migrations on startup, bootstraps the
feeds table from TOML, mounts the API + HTML routers.
"""
from __future__ import annotations

import asyncio
from contextlib import asynccontextmanager
from pathlib import Path

from alembic import command
from alembic.config import Config as AlembicConfig
from fastapi import FastAPI
from fastapi.staticfiles import StaticFiles

from app.config import get_settings
from app.db import get_session_factory
from app.logging import configure_logging, get_logger
from app.routers import api as api_router
from app.routers import pages as pages_router
from app.services.feeds_bootstrap import bootstrap_feeds


log = get_logger("cassandra")
APP_DIR = Path(__file__).resolve().parent
PROJECT_DIR = APP_DIR.parent


def _run_migrations() -> None:
    """Synchronous Alembic upgrade. Called once at lifespan startup."""
    cfg = AlembicConfig(str(PROJECT_DIR / "alembic.ini"))
    cfg.set_main_option("script_location", str(PROJECT_DIR / "alembic"))
    cfg.set_main_option("sqlalchemy.url", get_settings().DATABASE_URL)
    command.upgrade(cfg, "head")


@asynccontextmanager
async def lifespan(app: FastAPI):
    configure_logging()
    log.info("cassandra.startup")
    try:
        # Alembic's env.py uses asyncio.run() internally; offload it to a
        # worker thread so it doesn't collide with FastAPI's running loop.
        await asyncio.to_thread(_run_migrations)
        log.info("cassandra.migrations.applied")
    except Exception as e:
        log.error("cassandra.migrations.failed", error=str(e))
        raise
    async with get_session_factory()() as session:
        inserted = await bootstrap_feeds(session)
        log.info("cassandra.feeds.bootstrap", inserted=inserted)
    yield
    log.info("cassandra.shutdown")


app = FastAPI(
    title="Cassandra",
    description="Macro-strategy dashboard",
    version="0.1.0",
    lifespan=lifespan,
)

app.mount(
    "/static",
    StaticFiles(directory=str(APP_DIR / "static")),
    name="static",
)

app.include_router(api_router.router, prefix="/api", tags=["api"])
app.include_router(pages_router.router, tags=["pages"])