From d78db75aebf941467fa449d13e3da1430fc44383 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Andreas=20Kr=C3=BChlmann?= <andreas@kruhlmann.dev>
Date: Fri, 23 Jan 2026 16:33:51 +0100
Subject: [PATCH] Use int values for canvas size

---
 .../service/ChannelDirectoryService.java      | 25 +++++++++++++++++++
 src/main/resources/static/js/dashboard.js     | 10 +++++---
 2 files changed, 32 insertions(+), 3 deletions(-)

diff --git a/src/main/java/dev/kruhlmann/imgfloat/service/ChannelDirectoryService.java b/src/main/java/dev/kruhlmann/imgfloat/service/ChannelDirectoryService.java
index 7745c8e..6163c5d 100644
--- a/src/main/java/dev/kruhlmann/imgfloat/service/ChannelDirectoryService.java
+++ b/src/main/java/dev/kruhlmann/imgfloat/service/ChannelDirectoryService.java
@@ -204,6 +204,7 @@ public class ChannelDirectoryService {
     }
 
     public CanvasSettingsRequest updateCanvasSettings(String broadcaster, CanvasSettingsRequest req, String actor) {
+        validateCanvasSettings(req);
         Channel channel = getOrCreateChannel(broadcaster);
         double beforeWidth = channel.getCanvasWidth();
         double beforeHeight = channel.getCanvasHeight();
@@ -230,6 +231,30 @@ public class ChannelDirectoryService {
         return response;
     }
 
+    private void validateCanvasSettings(CanvasSettingsRequest req) {
+        Settings settings = settingsService.get();
+        int canvasMaxSizePixels = settings.getMaxCanvasSideLengthPixels();
+
+        if (
+            req.getWidth() <= 0 ||
+            req.getWidth() > canvasMaxSizePixels ||
+            !Double.isFinite(req.getWidth()) ||
+            req.getWidth() % 1 != 0
+        ) throw new ResponseStatusException(
+            BAD_REQUEST,
+            "Canvas width must be a whole number within [1 to " + canvasMaxSizePixels + "]"
+        );
+        if (
+            req.getHeight() <= 0 ||
+            req.getHeight() > canvasMaxSizePixels ||
+            !Double.isFinite(req.getHeight()) ||
+            req.getHeight() % 1 != 0
+        ) throw new ResponseStatusException(
+            BAD_REQUEST,
+            "Canvas height must be a whole number within [1 to " + canvasMaxSizePixels + "]"
+        );
+    }
+
     public ChannelScriptSettingsRequest getChannelScriptSettings(String broadcaster) {
         Channel channel = getOrCreateChannel(broadcaster);
         return new ChannelScriptSettingsRequest(
diff --git a/src/main/resources/static/js/dashboard.js b/src/main/resources/static/js/dashboard.js
index c109730..e4c2d21 100644
--- a/src/main/resources/static/js/dashboard.js
+++ b/src/main/resources/static/js/dashboard.js
@@ -216,12 +216,16 @@ async function fetchCanvasSettings() {
 }
 
 async function saveCanvasSettings() {
-    const width = parseFloat(elements.canvasWidth?.value) || 0;
-    const height = parseFloat(elements.canvasHeight?.value) || 0;
-    if (width <= 0 || height <= 0) {
+    const width = Number(elements.canvasWidth?.value);
+    const height = Number(elements.canvasHeight?.value);
+    if (!Number.isFinite(width) || !Number.isFinite(height) || width <= 0 || height <= 0) {
         showToast("Please enter a valid width and height.", "info");
         return;
     }
+    if (!Number.isInteger(width) || !Number.isInteger(height)) {
+        showToast("Please enter whole-number dimensions for the canvas size.", "info");
+        return;
+    }
     if (elements.canvasStatus) elements.canvasStatus.textContent = "Saving...";
     setButtonBusy(elements.canvasSaveButton, true, "Saving...");
     try {