from contextlib import asynccontextmanager
from fastapi import FastAPI, Body, Depends, HTTPException
from fastapi.responses import JSONResponse
from sqlalchemy.ext.asyncio import AsyncSession
from typing import Annotated

from .database.connection import engine
from .database.base import SQLModel       # Ensures all models in base.py are visible
from .routes.activities_router import router as activity_router
from .routes.auth_router import router as auth_router
from .routes.goal_router import router as goal_router
from .routes.daylog_router import router as day_logs_router
from .routes.transaction_router import router as transaction_router
from .routes.analytics_router import router as analytics_router
from .database.connection import get_session
from .database.models import User
from .utils.auth import get_current_user
from .utils.services import CommandError, command_error_payload, dispatch_command
from fastapi.middleware.cors import CORSMiddleware
import logging

logger = logging.getLogger(__name__)


# 1. Lifespan event for startup and shutdown actions
@asynccontextmanager
async def lifespan(app: FastAPI):

    logger.info("Starting up the application...")
    # Startup actions: Create database tables if they do not exist
    async with engine.begin() as conn:
        await conn.run_sync(SQLModel.metadata.create_all)
    
    yield  # Application runs here
    
    # Shutdown actions (e.g., closing connection pools if necessary)
    await engine.dispose()

app = FastAPI(lifespan=lifespan)


app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"],     # Accept requests from anywhere
    allow_credentials=False, # Must be False when using "*"
    allow_methods=["*"],
    allow_headers=["*"],
)

# Register your routes into the core application
app.include_router(auth_router)
app.include_router(activity_router)
app.include_router(goal_router)
app.include_router(day_logs_router)
app.include_router(transaction_router)
app.include_router(analytics_router)

@app.get("/")
def read_root():
    return {"message": "DailyMetric backend is running"}

@app.post("/chat")
async def chat_endpoint(
    current_user: Annotated[User, Depends(get_current_user)],
    command: str = Body(..., embed=True),
    db: AsyncSession = Depends(get_session),
):
    try:
        return await dispatch_command(command, current_user, db)
    except CommandError as exc:
        return JSONResponse(status_code=exc.status_code, content=command_error_payload(exc))

@app.get("/health")
def health_check():
    return {"status": "healthy"}