From 52c51fbf3ff25f5ebc163eaa7216d52fdb76fd4b Mon Sep 17 00:00:00 2001
From: Eddy <eddy@MacMini.local>
Date: Mon, 11 May 2026 20:02:16 +0200
Subject: [PATCH 1/4] feat: add rate limiter module

---
 src/rateLimiter.js | 32 ++++++++++++++++++++++++++++++++
 1 file changed, 32 insertions(+)
 create mode 100644 src/rateLimiter.js

diff --git a/src/rateLimiter.js b/src/rateLimiter.js
new file mode 100644
index 0000000..311dce4
--- /dev/null
+++ b/src/rateLimiter.js
@@ -0,0 +1,32 @@
+const MAX_REQUESTS_PER_DAY = parseInt(process.env.MAX_REQUESTS_PER_DAY, 10) || 5
+
+const userCounts = new Map()
+let currentDate = new Date().toDateString()
+
+function resetIfNeeded() {
+  const today = new Date().toDateString()
+  if (today !== currentDate) {
+    userCounts.clear()
+    currentDate = today
+    console.log('Rate limiter: daily counters reset')
+  }
+}
+
+function checkLimit(userId) {
+  resetIfNeeded()
+  const count = userCounts.get(userId) || 0
+  return {
+    allowed: count < MAX_REQUESTS_PER_DAY,
+    count,
+    max: MAX_REQUESTS_PER_DAY
+  }
+}
+
+function increment(userId) {
+  resetIfNeeded()
+  const count = (userCounts.get(userId) || 0) + 1
+  userCounts.set(userId, count)
+  return count
+}
+
+module.exports = { checkLimit, increment, MAX_REQUESTS_PER_DAY }

From 3d933c96a6611efd22390357ff2e801428092890 Mon Sep 17 00:00:00 2001
From: Eddy <eddy@MacMini.local>
Date: Mon, 11 May 2026 20:07:07 +0200
Subject: [PATCH 2/4] feat: integrate rate limiter into message handler

---
 src/messageHandler.js | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/messageHandler.js b/src/messageHandler.js
index d57d9f7..789a84b 100644
--- a/src/messageHandler.js
+++ b/src/messageHandler.js
@@ -1,5 +1,6 @@
 const { findDienst, getPngFilePaths } = require('./dienstService')
 const { sendTextMessage, sendImageMessage, notifyAdmin } = require('./whatsappApi')
+const { checkLimit, increment, MAX_REQUESTS_PER_DAY } = require('./rateLimiter')
 
 const BOT_NAME = (process.env.BOT_NAME || 'EdGpt').toLowerCase()
 const ALLOWED_GROUP = process.env.ALLOWED_GROUP
@@ -40,6 +41,15 @@ async function handleWebhook(payload) {
   const author = message.author
   if (!author) return
 
+  const limit = checkLimit(author)
+  if (!limit.allowed) {
+    await sendTextMessage(author, `Je hebt vandaag het maximum van ${limit.max} diensten bereikt. Probeer het morgen opnieuw.`)
+    console.log(`Rate limit reached for ${author} (${limit.count}/${limit.max})`)
+    return
+  }
+
+  increment(author)
+
   const dienst = findDienst(dienstnummer)
   if (!dienst) {
     await sendTextMessage(author, `Dienstnummer ${dienstnummer} niet gevonden.`)

From 100b2af449d70cd4844a27ba28fe17f1cafdd544 Mon Sep 17 00:00:00 2001
From: Eddy <eddy@MacMini.local>
Date: Mon, 11 May 2026 20:10:42 +0200
Subject: [PATCH 3/4] feat: add rate limiting config option

---
 .env.example | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/.env.example b/.env.example
index 952158d..168e1aa 100644
--- a/.env.example
+++ b/.env.example
@@ -11,5 +11,8 @@ BOT_NAME=EdGpt
 DIENSTEN_JSON=./diensten/dienst-tijden.json
 DIENSTEN_PNG=./diensten/png
 
+# Rate limiting
+MAX_REQUESTS_PER_DAY=5
+
 # Admin notifications
 ADMIN_NUMBER=31612345678@c.us

From 7176f09387518a08d216aa0e2d420d7269389da6 Mon Sep 17 00:00:00 2001
From: Eddy <eddy@MacMini.local>
Date: Mon, 11 May 2026 20:11:45 +0200
Subject: [PATCH 4/4] docs: add spam protection section and rateLimiter.js to
 README

---
 README.md | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/README.md b/README.md
index 15cf63d..d6f8366 100644
--- a/README.md
+++ b/README.md
@@ -114,6 +114,7 @@ npx pm2 logs dienst-bot
 src/
   index.js           # Express webhook server
   messageHandler.js  # Berichtverwerking en filtering
+  rateLimiter.js     # Spam protectie (max 5 per dag)
   dienstService.js   # JSON lookup en PNG bestandspaden
   whatsappApi.js     # WhatsApp API client (bericht + afbeelding)
 ```
@@ -124,6 +125,10 @@ src/
 - **Fout bij verzenden PNG**: de admin krijgt een WhatsApp melding
 - **Webhook fout**: wordt gelogd in PM2 logs
 
+## Spam protectie
+
+Elke gebruiker kan maximaal `MAX_REQUESTS_PER_DAY` (standaard 5) diensten per dag opvragen. Bij overschrijding krijgt de gebruiker een melding. De teller wordt dagelijks automatisch gereset (bij de eerste request na middernacht).
+
 ## Licentie
 
 Privé project — niet voor distributie.