from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware
from contextlib import asynccontextmanager
from sqlalchemy import text
import asyncio

from app.core.database import engine, AsyncSessionLocal, Base
from app.core.config import settings
from app.api import auth, activities, routes, health, records, upload, profile, garmin_sync


async def init_db():
    """Create tables then seed admin, with retries for slow DB startup.

    Multiple uvicorn workers may race here on first start. We tolerate
    duplicate table errors since they just mean another worker got there first.
    """
    for attempt in range(15):
        try:
            async with engine.begin() as conn:
                await conn.run_sync(Base.metadata.create_all)
            break
        except Exception as e:
            msg = str(e).lower()
            if "already exists" in msg or "duplicate" in msg or "pg_type_typname" in msg:
                print("Tables already created by another worker - skipping")
                break
            if attempt == 14:
                raise
            print(f"DB not ready yet (attempt {attempt + 1}/15): {e}")
            await asyncio.sleep(2)

    # Try TimescaleDB hypertable (non-fatal)
    try:
        async with engine.begin() as conn:
            await conn.execute(text(
                "SELECT create_hypertable('activity_data_points', 'timestamp', "
                "if_not_exists => TRUE, migrate_data => TRUE)"
            ))
    except Exception as e:
        print(f"TimescaleDB hypertable skipped: {e}")

    # Seed admin user (only if password is configured)
    if not settings.admin_password:
        print("ADMIN_PASSWORD not set - skipping admin user seed")
        return

    from sqlalchemy import select
    from app.models.user import User
    from app.core.security import hash_password

    try:
        async with AsyncSessionLocal() as db:
            result = await db.execute(
                select(User).where(User.username == settings.admin_username)
            )
            if not result.scalar_one_or_none():
                admin = User(
                    username=settings.admin_username,
                    hashed_password=hash_password(settings.admin_password),
                    is_admin=True,
                )
                db.add(admin)
                await db.commit()
                print(f"Admin user '{settings.admin_username}' created")
    except Exception as e:
        msg = str(e).lower()
        if "duplicate" in msg or "unique" in msg:
            print("Admin user already exists - skipping seed")
        else:
            raise


@asynccontextmanager
async def lifespan(app: FastAPI):
    await init_db()
    yield


app = FastAPI(
    title="MileVault",
    version="1.0.0",
    lifespan=lifespan,
)

app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"] if settings.environment == "development" else [],
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

app.include_router(auth.router, prefix="/api/auth", tags=["auth"])
app.include_router(activities.router, prefix="/api/activities", tags=["activities"])
app.include_router(routes.router, prefix="/api/routes", tags=["routes"])
app.include_router(health.router, prefix="/api/health-metrics", tags=["health"])
app.include_router(records.router, prefix="/api/records", tags=["records"])
app.include_router(upload.router, prefix="/api/upload", tags=["upload"])
app.include_router(profile.router, prefix="/api/profile", tags=["profile"])
app.include_router(garmin_sync.router, prefix="/api/garmin-sync", tags=["garmin-sync"])


@app.get("/health")
async def healthcheck():
    return {"status": "ok"}