from flask import Flask, request, jsonify
from flask_cors import CORS
import joblib
import pandas as pd
import os
import psycopg2
from datetime import datetime
import uuid
import jwt

# ================= CONFIG =================

DATABASE_URL = os.environ.get("DATABASE_URL")
JWT_SECRET = os.environ.get("JWT_SECRET")

if not DATABASE_URL:
    raise RuntimeError("DATABASE_URL is not set in environment variables")

if not JWT_SECRET:
    raise RuntimeError("JWT_SECRET is not set in environment variables")

# ================= LOAD MODEL =================

if not os.path.exists("diabetes_model_tuned2.pkl"):
    import gdown
    url = "https://drive.google.com/uc?id=1Zo-xI1y3Y64HU6aiwXVUIHXfu84bBphx"
    gdown.download(url, "diabetes_model_tuned2.pkl", quiet=False)

model = joblib.load("diabetes_model_tuned2.pkl")

# ================= APP =================

app = Flask(__name__)

# 🔹 Konfigurasi CORS yang lebih lengkap
CORS(app,
     resources={r"/*": {
         "origins": [
             "http://localhost:5173",
             "http://localhost:3000",
             "https://capstone-dbs-react.vercel.app",
             r"https://.*\.ngrok-free\.app"
         ],
         "methods": ["GET", "POST", "OPTIONS"],
         "allow_headers": ["Content-Type", "Authorization"],
         "supports_credentials": True
     }})


def get_db_connection():
    try:
        return psycopg2.connect(DATABASE_URL)
    except Exception as e:
        print(f"Database connection error: {e}")
        return None

# ================= JWT HELPER =================

def get_user_id_from_token(request):
    auth_header = request.headers.get("Authorization")
    if not auth_header:
        return None

    try:
        scheme, token = auth_header.split()
        if scheme.lower() != "bearer":
            return None

        decoded = jwt.decode(token, JWT_SECRET, algorithms=["HS256"])
        return decoded.get("userId") or decoded.get("id")
    except Exception as e:
        print("JWT decode error:", e)
        return None

# ================= ROUTES =================

@app.route('/')
def home():
    return "API is running"

@app.route('/predict-history', methods=['POST'])
def predict_history():    
    try:
        data = request.get_json()
        if not data:
            return jsonify({'error': 'No data provided'}), 400

        required_fields = [
            'hypertension', 'heart_disease', 'bmi', 'blood_glucose_level',
            'HbA1c_level', 'smoking_history', 'gender', 'age'
        ]

        for field in required_fields:
            if field not in data:
                return jsonify({'error': f'Missing field: {field}'}), 400

        # 🔹 Ambil userId dari JWT (boleh None)
        current_user_id = get_user_id_from_token(request)

        input_data = pd.DataFrame([{
            'hypertension': int(data['hypertension']),
            'heart_disease': int(data['heart_disease']),
            'bmi': float(data['bmi']),
            'blood_glucose_level': float(data['blood_glucose_level']),
            'HbA1c_level': float(data['HbA1c_level']),
            'smoking_history': data['smoking_history'],
            'gender': data['gender'],
            'age': float(data['age'])
        }])

        prediction = model.predict(input_data)[0]
        proba = model.predict_proba(input_data)[0]
        confidence = float(proba[1]) if prediction == 1 else float(proba[0])
        prediction_result = "positive" if prediction == 1 else "negative"

        conn = get_db_connection()
        if not conn:
            return jsonify({'error': 'Database connection failed'}), 500

        try:
            cursor = conn.cursor()
            insert_query = """
                INSERT INTO form_check_history 
                (id, "userId", hypertension, "heartDisease", bmi, "bloodGlucoseLevel", 
                 "hba1cLevel", "smokingHistory", gender, age, "predictionResult", "createdAt", "updatedAt") 
                VALUES (%s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s, %s)
                RETURNING id
            """

            record_id = str(uuid.uuid4())
            current_time = datetime.now()

            cursor.execute(insert_query, (
                record_id,
                current_user_id,
                bool(int(data['hypertension'])),
                bool(int(data['heart_disease'])),
                float(data['bmi']),
                float(data['blood_glucose_level']),
                float(data['HbA1c_level']),
                data['smoking_history'],
                data['gender'],
                float(data['age']),
                prediction_result,
                current_time,
                current_time
            ))

            conn.commit()
            cursor.close()
            conn.close()

            return jsonify({
                'success': True,
                'message': 'Prediction completed and saved successfully',
                'recordId': record_id,
                'prediction': {
                    'result': int(prediction),
                    'resultText': prediction_result,
                    'confidence': round(confidence, 4)
                },
                'inputData': data,
                'timestamp': current_time.isoformat(),
                'userId': current_user_id
            }), 200

        except Exception as db_error:
            conn.rollback()
            cursor.close()
            conn.close()
            return jsonify({'error': f'Database error: {str(db_error)}'}), 500

    except Exception as e:
        return jsonify({'error': f'Prediction error: {str(e)}'}), 500

# ================= RUN =================

if __name__ == "__main__":
    app.run(host="0.0.0.0", port=int(os.environ.get("PORT", 7860)), debug=False)