from contextlib import asynccontextmanager
from pathlib import Path

from fastapi import FastAPI, HTTPException
from fastapi.middleware.cors import CORSMiddleware
from fastapi.responses import FileResponse
from fastapi.staticfiles import StaticFiles
from sqlalchemy import select

from app.api.v1.router import api_router
from app.auth.api_key import hash_api_key
from app.config import get_settings
from app.database import SessionLocal
from app.models import ApiKey

ROOT = Path(__file__).resolve().parents[2]


def bootstrap_api_key() -> None:
    settings = get_settings()
    if not settings.sac_bootstrap_api_key:
        return
    db = SessionLocal()
    try:
        key_hash = hash_api_key(settings.sac_bootstrap_api_key)
        exists = db.scalar(select(ApiKey).where(ApiKey.key_hash == key_hash))
        if exists:
            return
        prefix = settings.sac_bootstrap_api_key[:12]
        db.add(
            ApiKey(
                name="bootstrap",
                key_prefix=prefix,
                key_hash=key_hash,
                is_active=True,
            )
        )
        db.commit()
    finally:
        db.close()


@asynccontextmanager
async def lifespan(_app: FastAPI):
    bootstrap_api_key()
    yield


def create_app() -> FastAPI:
    settings = get_settings()
    app = FastAPI(
        title="Security Alert Center",
        version="0.1.0",
        lifespan=lifespan,
    )
    origins = [o.strip() for o in settings.cors_origins.split(",") if o.strip()]
    app.add_middleware(
        CORSMiddleware,
        allow_origins=origins if origins != ["*"] else ["*"],
        allow_credentials=True,
        allow_methods=["*"],
        allow_headers=["*"],
    )
    from app.api.v1.health import router as health_router

    app.include_router(api_router, prefix="/api/v1")
    app.include_router(health_router)

    frontend_dist = ROOT / "frontend" / "dist"
    if frontend_dist.is_dir():
        assets_dir = frontend_dist / "assets"
        if assets_dir.is_dir():
            app.mount(
                "/assets",
                StaticFiles(directory=str(assets_dir)),
                name="ui-assets",
            )

        @app.get("/{spa_path:path}")
        def spa_fallback(spa_path: str) -> FileResponse:
            if spa_path.startswith("api/"):
                raise HTTPException(status_code=404, detail="Not Found")
            candidate = frontend_dist / spa_path
            if spa_path and candidate.is_file():
                return FileResponse(candidate)
            index = frontend_dist / "index.html"
            if not index.is_file():
                raise HTTPException(status_code=404, detail="UI not built")
            return FileResponse(index)

    return app


app = create_app()