Security and Location-Aware Logic for BBQ Heaven Rockingham

README.md

🍖 BBQ Heaven: Technical Architecture & Security

This Gist outlines the core logic powering the BBQ Heaven Rockingham ordering ecosystem, focusing on security, location-aware ordering, and real-time synchronization.

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🔒 1. Access Control & Security (RBAC)

The system leverages Firebase Authentication and Realtime Database Rules to enforce Role-Based Access Control:

• Customers: Granted Write-Only access to the orders node. This allows order submission while preventing customers from viewing other people's data.
• Staff/Admin: Validated via a custom role attribute in the users node. Only authenticated admin UIDs can read the live order stream on the Kitchen Dashboard.
• Data Integrity: Strict type-casting in order-system.js ensures values like pricing and quantities are validated before being written to the NoSQL database.

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📍 2. Precision GPS Geofencing

To prevent accidental orders from users outside of Western Australia (common due to mobile IP routing to Eastern States), we use the Web Geolocation API:

• Logic: Uses the Haversine Formula to calculate the mathematical distance between the user’s device and the Rockingham smokehouse.
• Radius Lock: A strict 60km limit is enforced (covering Perth to Mandurah).
• UI Response: If the user is outside the zone, the system dynamically disables the "Place Order" button and updates the UI to "PICKUP ONLY (OUTSIDE AREA)".

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⚡ 3. Real-Time Order Synchronization

Built on Firebase Realtime Database (NoSQL), the system maintains a sub-second "Customer-to-Pit Pipeline":

• WebSocket Protocol: Unlike REST APIs, the onValue listener keeps a bi-directional connection open.
• Performance: When a customer clicks "Place Order," the kitchen monitor reflects the change in <200ms, allowing staff to react instantly.

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👥 4. Live Presence & Footer Logic

The site footer features dynamic data powered by Supabase Presence and AWST-Aware Logic:

Real-Time Visitor Count

• Tracking: Uses Supabase Channels to track active browser sessions.
• Session IDs: Generates a random alphanumeric sessionId per tab to differentiate between mobile and desktop users.
• Instant Updates: The .on('presence', { event: 'sync' }) listener automatically updates the #user-count element in the footer as visitors join or leave.

Smart Business Status

• Perth Time: Uses Intl.DateTimeFormat to calculate status based on Australia/Perth time, ignoring the user's local system clock.
• Split Schedules: Accounts for complex split-shift hours (e.g., Wednesday lunch and dinner windows).
• Dynamic UI: Includes a CSS-animated pulse indicator and context-aware hints (e.g., "Re-opens at 5:00 PM").

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🛠️ Integration Example

To initialize the footer logic, import the utilities into your main.js:

import { initLiveCounter, updateBusinessStatus } from './realtime-utils.js';

// Start presence tracking
initLiveCounter();

// Set initial status and refresh every 60 seconds
updateBusinessStatus();
setInterval(updateBusinessStatus, 60000);

CSS: Live Status Indicator

/* Animated Pulse for Live Status */
.animate-ping {
    animation: ping 1.5s cubic-bezier(0, 0, 0.2, 1) infinite;
}

@keyframes ping {
    75%, 100% {
        transform: scale(2);
        opacity: 0;
    }
}

geofencing-logic.js

/**
 * BBQ Heaven GPS Geofencing Logic
 * Purpose: Restrict ordering to local WA customers (60km radius)
 */

const SHOP_LOCATION = { lat: -32.2807, lng: 115.7358 }; // Rockingham, WA
const MAX_RADIUS_KM = 60;

function calculateDistance(lat1, lon1, lat2, lon2) {
    const R = 6371; // Earth's radius in km
    const dLat = (lat2 - lat1) * Math.PI / 180;
    const dLon = (lon2 - lon1) * Math.PI / 180;
    const a = 
        Math.sin(dLat/2) * Math.sin(dLat/2) +
        Math.cos(lat1 * Math.PI / 180) * Math.cos(lat2 * Math.PI / 180) * Math.sin(dLon/2) * Math.sin(dLon/2);
    const c = 2 * Math.atan2(Math.sqrt(a), Math.sqrt(1-a));
    return R * c;
}

export function validateCustomerLocation() {
    if (!navigator.geolocation) {
        console.error("Geolocation not supported");
        return;
    }

    navigator.geolocation.getCurrentPosition((position) => {
        const userDist = calculateDistance(
            position.coords.latitude, 
            position.coords.longitude,
            SHOP_LOCATION.lat,
            SHOP_LOCATION.lng
        );

        const orderBtn = document.getElementById('place-order-btn');
        if (userDist > MAX_RADIUS_KM) {
            orderBtn.disabled = true;
            orderBtn.innerText = "PICKUP ONLY (OUTSIDE AREA)";
            orderBtn.classList.add('bg-gray-500');
        }
    });
}

rbac-config.json

{
  "rules": {
    "orders": {
      ".read": "auth != null && root.child('users').child(auth.uid).child('role').val() === 'admin'",
      "$order_id": {
        ".write": "auth == null || !data.exists()", 
        ".validate": "newData.hasChildren(['items', 'total', 'timestamp'])"
      }
    },
    "users": {
      "$uid": {
        ".read": "auth != null && auth.uid === $uid",
        ".write": "auth != null && auth.uid === $uid && !newData.child('role').exists()"
      }
    }
  }
}

realtime-utils.js

/**
 * BBQ HEAVEN REAL-TIME UTILITIES
 * ------------------------------
 * 1. Live Presence Counter via Supabase
 * 2. AWST Business Hours Logic
 */

import { supabaseClient } from "./config.js";

/**
 * Initializes the Supabase Presence channel to track live users.
 * Generates unique session IDs to differentiate devices.
 */
export function initLiveCounter() {
  const sessionId = Math.random().toString(36).slice(2, 11);

  const channel = supabaseClient.channel("online-users", {
    config: {
      presence: { key: sessionId },
    },
  });

  channel
    .on("presence", { event: "sync" }, () => {
      const state = channel.presenceState();
      const count = Object.keys(state).length;

      const countEl = document.getElementById("user-count");
      if (countEl) {
        countEl.textContent = count;
      }
    })
    .subscribe(async (status) => {
      if (status === "SUBSCRIBED") {
        await channel.track({
          online_at: new Date().toISOString(),
          device: navigator.userAgent.includes("Mobi") ? "mobile" : "desktop",
        });
      }
    });
}

/**
 * Calculates if the business is open based on Perth/Rockingham time (AWST).
 * Updates UI elements for status text, color, and opening hour hints.
 */
export function updateBusinessStatus() {
  const statusText = document.getElementById("status-text");
  const statusDot = document.getElementById("status-dot");
  const hoursHint = document.getElementById("opening-hours-hint");

  if (!statusText) return;

  const now = new Date();
  const formatter = new Intl.DateTimeFormat("en-AU", {
    timeZone: "Australia/Perth",
    hour: "numeric",
    minute: "numeric",
    hour12: false,
    weekday: "long",
  });

  const parts = formatter.formatToParts(now);
  const day = parts.find((p) => p.type === "weekday").value;
  const hour = parseInt(parts.find((p) => p.type === "hour").value);
  const minute = parseInt(parts.find((p) => p.type === "minute").value);
  const currentTime = hour + minute / 60;

  // Business Hours Data (24h format)
  const schedule = {
    Monday: [[17, 21]],
    Tuesday: [[17, 21]],
    Wednesday: [[11.5, 14.5], [17, 21]],
    Thursday: [[11.5, 14.5], [17, 21]],
    Friday: [[11.5, 14.5], [17, 21]],
    Saturday: [[11.5, 21]],
    Sunday: [[11.5, 21]],
  };

  const todayHours = schedule[day];
  let isOpen = false;

  todayHours.forEach((window) => {
    if (currentTime >= window[0] && currentTime < window[1]) {
      isOpen = true;
    }
  });

  if (isOpen) {
    statusText.textContent = "Open Now";
    statusText.className = "text-green-500 text-lg uppercase tracking-tighter";
    if (statusDot)
      statusDot.className = "h-3 w-3 rounded-full bg-green-500 animate-pulse shadow-[0_0_10px_rgba(34,197,94,0.8)]";
    if (hoursHint) hoursHint.textContent = "Pit is hot until 9:00 PM";
  } else {
    statusText.textContent = "Closed";
    statusText.className = "text-red-500 text-lg uppercase tracking-tighter";
    if (statusDot) statusDot.className = "h-3 w-3 rounded-full bg-red-500";

    if (hoursHint) {
      if (day === "Monday" || day === "Tuesday") {
        hoursHint.textContent = "Opens at 5:00 PM";
      } else {
        hoursHint.textContent = currentTime < 11.5 ? "Opens at 11:30 AM" : "Re-opens at 5:00 PM";
      }
    }
  }
}

supabase-presence.js

import { createClient } from '@supabase/supabase-js'

// Initialize Supabase client
const supabaseUrl = 'https://your-project-url.supabase.co'
const supabaseKey = 'your-anon-key'
const supabase = createClient(supabaseUrl, supabaseKey)

/**
 * Syncs the live visitor count in the footer.
 * Uses Supabase Presence to track active tabs/sessions.
 */
export const initLivePresence = () => {
  const userCountEl = document.getElementById('user-count');
  
  // Create a channel for the 'pit' (your site)
  const channel = supabase.channel('online-visitors', {
    config: {
      presence: {
        key: 'user',
      },
    },
  });

  channel
    .on('presence', { event: 'sync' }, () => {
      const state = channel.presenceState();
      // Count total members across all keys
      const count = Object.keys(state).length;
      
      if (userCountEl) {
        userCountEl.textContent = count;
      }
    })
    .subscribe(async (status) => {
      if (status === 'SUBSCRIBED') {
        // Track this user with a unique timestamp or random ID
        await channel.track({
          online_at: new Date().toISOString(),
          visitor_id: Math.random().toString(36).substring(2, 9)
        });
      }
    });
};

// Auto-initialize if script is loaded
document.addEventListener('DOMContentLoaded', initLivePresence);

sync-logic.js

/**
 * BBQ Heaven Real-Time Sync Logic
 * Purpose: Sub-second synchronization between Customer and Kitchen
 */

import { getDatabase, ref, onValue, push, set } from "firebase/database";

const db = getDatabase();

// 1. Customer Side: Pushing a new order
export function submitOrder(orderData) {
    const ordersRef = ref(db, 'orders');
    const newOrderRef = push(ordersRef);
    
    // Ensure data is sanitized before write to prevent NoSQL injection/errors
    return set(newOrderRef, {
        ...orderData,
        timestamp: Date.now(),
        status: 'pending'
    });
}

// 2. Kitchen Side: Listening for instant updates
export function listenForOrders(callback) {
    const ordersRef = ref(db, 'orders');
    
    // onValue creates a persistent websocket connection for "Instant Sync"
    onValue(ordersRef, (snapshot) => {
        const data = snapshot.val();
        const formattedOrders = [];
        
        for (let id in data) {
            formattedOrders.push({ id, ...data[id] });
        }
        
        // Callback updates the Kitchen Dashboard UI immediately
        callback(formattedOrders.reverse()); 
    });
}