import logging
import sys
from contextlib import asynccontextmanager
from pathlib import Path

from fastapi import FastAPI, HTTPException

# When started via uvicorn --log-config the "subfeed" logger is already configured
# (see log_config.json). This block is a timestamped fallback for other entrypoints
# (tests, scripts) so our logs are never silently dropped.
_subfeed_logger = logging.getLogger("subfeed")
if not _subfeed_logger.handlers:
    _handler = logging.StreamHandler(sys.stdout)
    _handler.setFormatter(
        logging.Formatter("%(asctime)s %(levelname)-5s [%(name)s] %(message)s")
    )
    _subfeed_logger.addHandler(_handler)
    _subfeed_logger.setLevel(logging.INFO)
    _subfeed_logger.propagate = False

log = logging.getLogger("subfeed.app")
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import FileResponse
from fastapi.staticfiles import StaticFiles
from starlette.middleware.sessions import SessionMiddleware

from app import auth
from app.config import settings
from app.routes import (
    admin,
    channels,
    config as config_routes,
    feed,
    health,
    me,
    notifications,
    playlists,
    quota,
    scheduler as scheduler_routes,
    sync,
    tags,
    version,
)
from app.scheduler import shutdown_scheduler, start_scheduler


@asynccontextmanager
async def lifespan(app: FastAPI):
    log.info("Siftlode starting up")
    start_scheduler()
    try:
        yield
    finally:
        log.info("Siftlode shutting down")
        shutdown_scheduler()


app = FastAPI(title=settings.app_name, lifespan=lifespan)

app.add_middleware(
    SessionMiddleware,
    secret_key=settings.secret_key,
    same_site="lax",  # required so the cookie rides the OAuth redirect back from Google
    https_only=settings.session_https_only,  # Secure flag when served over HTTPS (prod)
)

if settings.frontend_origin:
    app.add_middleware(
        CORSMiddleware,
        allow_origins=[settings.frontend_origin],
        allow_credentials=True,
        allow_methods=["*"],
        allow_headers=["*"],
    )

app.include_router(health.router)
app.include_router(auth.router)
app.include_router(sync.router)
app.include_router(tags.router)
app.include_router(feed.router)
app.include_router(me.router)
app.include_router(notifications.router)
app.include_router(channels.router)
app.include_router(playlists.router)
app.include_router(admin.router)
app.include_router(config_routes.router)
app.include_router(scheduler_routes.router)
app.include_router(quota.router)
app.include_router(version.router)

# The built SPA (populated by the Docker frontend build stage).
STATIC_DIR = Path(__file__).parent / "static_spa"
app.mount(
    "/assets",
    StaticFiles(directory=STATIC_DIR / "assets", check_dir=False),
    name="assets",
)


@app.get("/")
async def index() -> FileResponse:
    return FileResponse(STATIC_DIR / "index.html")


@app.get("/{full_path:path}")
async def spa_fallback(full_path: str) -> FileResponse:
    # Client-side routes fall back to index.html; real API/asset paths are matched above.
    if full_path.startswith(("api/", "auth/", "healthz", "assets/")):
        raise HTTPException(status_code=404)
    # Serve real files that live at the SPA root (Vite copies public/ there — e.g. the landing
    # screenshots under /welcome/, favicon). /assets is already mounted above; everything else
    # that isn't a real file is a client-side route → index.html. Guard against path traversal.
    if full_path:
        candidate = (STATIC_DIR / full_path).resolve()
        if candidate.is_file() and STATIC_DIR.resolve() in candidate.parents:
            return FileResponse(candidate)
    return FileResponse(STATIC_DIR / "index.html")