from contextlib import asynccontextmanager

from fastapi import FastAPI
from fastapi.middleware.cors import CORSMiddleware

from app.api.documents import router as documents_router
from app.api.onboarding import router as onboarding_router
from app.api.voice_onboarding import router as voice_router
from app.database import models
from app.database.database import Base, engine


@asynccontextmanager
async def lifespan(app: FastAPI):
    Base.metadata.create_all(bind=engine)
    yield


app = FastAPI(
    title="AI Patient Onboarding API",
    description="Multi-Model Voice-First Hospital Patient Onboarding Engine (Sarvam + OpenAI + Claude + Gemini)",
    version="1.0.0",
    lifespan=lifespan,
)

from uuid import uuid4
from fastapi import Request
from fastapi.responses import JSONResponse
from app.config import CORS_ORIGINS

# Global Exception Handler (Hides Stack Traces in Production)
@app.exception_handler(Exception)
async def global_exception_handler(request: Request, exc: Exception):
    import traceback
    print(f"[Unhandled Server Error] Path: {request.url.path} Error: {exc}")
    traceback.print_exc()
    return JSONResponse(
        status_code=500,
        content={
            "success": False,
            "error": {
                "code": "INTERNAL_SERVER_ERROR",
                "message": "An unexpected internal server error occurred. Please contact system administration.",
            }
        }
    )

# Security Headers & Request Correlation Middleware
@app.middleware("http")
async def security_and_request_id_middleware(request: Request, call_next):
    request_id = request.headers.get("X-Request-ID") or f"req_{uuid4().hex[:12]}"
    response = await call_next(request)
    response.headers["X-Request-ID"] = request_id
    response.headers["X-Content-Type-Options"] = "nosniff"
    response.headers["X-Frame-Options"] = "DENY"
    response.headers["Referrer-Policy"] = "strict-origin-when-cross-origin"
    return response

# Enable Production-Safe CORS for React Web & Mobile clients (Outermost Layer)
app.add_middleware(
    CORSMiddleware,
    allow_origins=CORS_ORIGINS,
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
    expose_headers=["X-Request-ID"],
)

app.include_router(onboarding_router)
app.include_router(voice_router)
app.include_router(documents_router)


from fastapi.staticfiles import StaticFiles
from fastapi.responses import FileResponse
import os

docs_dir = os.path.join(os.path.dirname(os.path.dirname(__file__)), "docs")
if os.path.exists(docs_dir):
    app.mount("/static", StaticFiles(directory=docs_dir), name="static")

@app.get("/")
@app.get("/dashboard")
async def serve_dashboard():
    dashboard_path = os.path.join(docs_dir, "index.html")
    if os.path.exists(dashboard_path):
        return FileResponse(dashboard_path)
    return {"message": "CureSelect AI Voice Backend Ready"}

@app.get("/health")
async def health():
    return {
        "success": True,
        "service": "AI Patient Onboarding",
        "status": "healthy",
        "models": {
            "speech": "Sarvam AI (Indian Languages) / OpenAI Whisper",
            "conversation": "OpenAI GPT-4o-mini",
            "validation": "Claude 3.5 Sonnet",
            "vision_documents": "Gemini 1.5 Flash",
        },
    }