app.py

from flask import Flask, request, jsonify
import firebase_admin
from firebase_admin import credentials, messaging
import os, json

app = Flask(__name__)

# --- Initialize Firebase Admin SDK securely ---
# Load Firebase credentials from environment variable
firebase_json = os.getenv("FIREBASE_CRED")

if firebase_json:
    try:
        cred = credentials.Certificate(json.loads(firebase_json))
        firebase_admin.initialize_app(cred)
        print("✅ Firebase initialized successfully.")
    except Exception as e:
        print(f"⚠️ Error initializing Firebase: {e}")
else:
    print("⚠️ FIREBASE_CRED environment variable not found! Firebase not initialized.")

# --- Store device tokens temporarily (use DB in real app) ---
REGISTERED_TOKENS = []


@app.route('/register', methods=['POST'])
def register_device():
    """Register a new device token."""
    data = request.json
    token = data.get("token")

    if not token:
        return jsonify({"error": "No token provided"}), 400

    if token not in REGISTERED_TOKENS:
        REGISTERED_TOKENS.append(token)
        print(f"✅ New device registered: {token[:10]}...")

    return jsonify({"message": "Device registered successfully!"}), 200


@app.route('/trigger', methods=['POST'])
def trigger_alert():
    """Triggered by ESP8266 when gas/flame is detected."""
    data = request.json
    if not data:
        return jsonify({"error": "No JSON data received"}), 400

    sensor_type = data.get("sensor")  # e.g. "flame" or "gas"
    status = data.get("status")       # e.g. "detected" or "clear"

    print(f"🔥 Trigger received: {sensor_type} = {status}")

    if status == "detected":
        title = f"{sensor_type.capitalize()} Alert!"
        body = f"{sensor_type.capitalize()} detected! Please check immediately."
    else:
        title = f"{sensor_type.capitalize()} Status Clear"
        body = f"No {sensor_type} detected now."

    # Send notification to all registered tokens
    for token in REGISTERED_TOKENS:
        message = messaging.Message(
            notification=messaging.Notification(
                title=title,
                body=body,
            ),
            token=token,
        )

        try:
            response = messaging.send(message)
            print(f"📩 Notification sent to {token[:10]}...: {response}")
        except Exception as e:
            print(f"⚠️ Error sending to {token[:10]}...: {e}")

    return jsonify({"message": "Trigger processed and notifications sent!"}), 200


if __name__ == '__main__':
    app.run(host='0.0.0.0', port=5000)