import sys
from fastapi import FastAPI, UploadFile, File, Depends, HTTPException, status
from fastapi.middleware.cors import CORSMiddleware
from sqlalchemy.orm import Session
from datetime import datetime

# Initialize FastAPI App
app = FastAPI(
    title="DocVerse Medical Intelligence API",
    description="FastAPI Backend for Document Scanning, NLP, and Risk Analysis",
    version="1.0.0",
)

# CORS Middleware Configurations
app.add_middleware(
    CORSMiddleware,
    allow_origins=["*"], # In production, restrict this
    allow_credentials=True,
    allow_methods=["*"],
    allow_headers=["*"],
)

from app.db.database import engine, get_db
from app.models.database_models import Base, User, Report, LabResult, RiskFlag

# Create all tables in DB if they don't exist
Base.metadata.create_all(bind=engine)

# Route Definitions
@app.get("/")
def health_check():
    return {"status": "ok", "timestamp": datetime.utcnow()}

@app.post("/api/v1/auth/register")
def register_user(user_data: dict, db: Session = Depends(get_db)):
    """ Register a new user and generate a JWT token """
    # Real logic: Hash password with passlib
    new_user = User(email=user_data.get("email"), password_hash="hashed_pw_here")
    db.add(new_user)
    db.commit()
    db.refresh(new_user)
    return {"message": "User registered successfully", "user_id": str(new_user.id)}

@app.post("/api/v1/auth/login")
def login(credentials: dict, db: Session = Depends(get_db)):
    """ Login user and return JWT """
    return {"access_token": "mock_jwt_token", "token_type": "bearer"}

@app.post("/api/v1/scan/upload")
async def upload_document(
    file: UploadFile = File(...), 
    current_user: str = "mock_user",  # JWT Dependency in reality
    db: Session = Depends(get_db)
):
    """ Upload document (PDF/Image) for OCR Processing """
    if not file.filename.endswith(('.pdf', '.png', '.jpg', '.jpeg')):
        raise HTTPException(status_code=400, detail="Invalid file format.")
    
    # 1. Encrypt and save file to secure storage (S3)
    # 2. Add Celery Task to process OCR and NLP
    task_id = "mock_task_id_999"
    return {"message": "File uploaded and processing started.", "task_id": task_id}

@app.get("/api/v1/scan/status/{task_id}")
def get_scan_status(task_id: str):
    """ Check the processing status of the OCR/NLP pipeline """
    return {"task_id": task_id, "status": "completed", "progress": 100}

@app.get("/api/v1/reports")
def get_reports(current_user: str = "mock_user", db: Session = Depends(get_db)):
    """ Get paginated list of encrypted user reports """
    # Real logic: Filter by current authenticated user
    reports = db.query(Report).all()
    return {"reports": [{"id": str(r.id), "file_name": r.file_name, "status": r.status} for r in reports]}

@app.get("/api/v1/health/labs")
def get_lab_trends(current_user: str = "mock_user", db: Session = Depends(get_db)):
    """ Retrieve timeline data for lab tests to chart in Flutter """
    labs = db.query(LabResult).all()
    return {"lab_trends": [{"test": l.test_name, "value": l.test_value, "flag": l.flag} for l in labs]}

@app.post("/api/v1/reminders")
def create_reminder(reminder: dict, current_user: str = "mock_user", db: Session = Depends(get_db)):
    """ Add a medication reminder """
    return {"message": "Reminder created successfully", "reminder_id": "999"}

if __name__ == "__main__":
    import uvicorn
    uvicorn.run("main:app", host="0.0.0.0", port=8000, reload=True)