minor fixes & mix node sample

src/App.vue

@@ -86,6 +86,7 @@ function onConnect(connection: Connection) {
   const srcHandle = connection.sourceHandle ?? ''
   const tgtHandle = connection.targetHandle ?? ''
   if (srcHandle.startsWith('video') !== tgtHandle.startsWith('video')) return
+  if (!srcHandle.includes('-out') || !tgtHandle.includes('-in')) return
   const kind = srcHandle.startsWith('video') ? 'video' : 'audio'
   edges.value = [
     ...edges.value,

src/components/NodePalette.vue

@@ -12,6 +12,7 @@ interface PaletteGroup {
 
 const groups: PaletteGroup[] = [
   { label: 'SOURCES',  types: ['testpattern', 'ndiin', 'decklinkin', 'videoin'] },
+  { label: 'PROCESS',   types: ['mix'] },
   { label: 'SINKS',    types: ['ndiout', 'decklinkout', 'fakesink'] },
 ]
 
@@ -23,6 +24,7 @@ const iconMap: Record<string, string> = {
   ndiout:       '◬',
   decklinkout:  '◧',
   fakesink:     '◯',
+  mix:          '⊕',
 }
 
 function onDragStart(event: DragEvent, nodeType: string) {

src/components/nodes/StudioNode.vue

@@ -12,7 +12,10 @@ const typeDef = computed(() => NODE_TYPES[props.data.nodeType] ?? null)
 const inputs  = computed(() => typeDef.value?.ports.filter(p => p.direction === 'in')  ?? [])
 const outputs = computed(() => typeDef.value?.ports.filter(p => p.direction === 'out') ?? [])
 
-const isSource = computed(() => outputs.value.length > 0)
+function portLabel(portId: string): string {
+  const parts = portId.split('-')
+  return parts.slice(0, -1).join(' ').toUpperCase()
+}
 
 const iconMap: Record<string, string> = {
   testpattern:  '▦',
@@ -22,6 +25,7 @@ const iconMap: Record<string, string> = {
   ndiout:       '◬',
   decklinkout:  '◧',
   fakesink:     '◯',
+  mix:          '⊕',
 }
 
 const nodeIcon = computed(() => iconMap[props.data.nodeType] ?? '◯')
@@ -91,12 +95,12 @@ function onDeleteNode() {
     <div v-if="inputs.length || outputs.length" class="node-ports">
       <div class="ports-side ports-left">
         <div v-for="port in inputs" :key="port.id" class="port-row">
-          <span :class="['port-name', `port-${port.kind}`]">{{ port.kind }}</span>
+          <span :class="['port-name', `port-${port.kind}`]">{{ portLabel(port.id) }}</span>
         </div>
       </div>
       <div class="ports-side ports-right">
         <div v-for="port in outputs" :key="port.id" class="port-row port-row-right">
-          <span :class="['port-name', `port-${port.kind}`]">{{ port.kind }}</span>
+          <span :class="['port-name', `port-${port.kind}`]">{{ portLabel(port.id) }}</span>
         </div>
       </div>
     </div>

src/graphBuilder.ts

@@ -25,8 +25,9 @@ function parseRes(res: string): { width: number; height: number } {
 
 // Converts a Vue Flow handle id to the NODE_CONFIG port key used in graph JSON
 function handleToPort(handle: string): string {
-  return handle.replace(/-(?:in|out)$/, '_flow_id')
+  return handle.replace(/-(?:in|out)(?:-\d+)?$/, '_flow_id')
   // 'video-out' → 'video_flow_id', 'audio-in' → 'audio_flow_id'
+  // 'video-in-1' → 'video_flow_id', 'audio-in-2' → 'audio_flow_id'
 }
 
 export function buildGraph(vfNodes: Node[], vfEdges: Edge[]): GraphJson {

src/nodeTypes.ts

@@ -31,6 +31,20 @@ export const PATTERN_OPTIONS = [
   { label: 'White solid', value: 'white' },
 ]
 
+export const MIX_MODE_OPTIONS = [
+  { label: 'Fade',     value: 'fade' },
+  { label: 'Dissolve', value: 'dissolve' },
+  { label: 'Wipe',     value: 'wipe' },
+  { label: 'A/B',     value: 'ab' },
+]
+
+export const TRANSITION_OPTIONS = [
+  { label: 'Cut',     value: 'cut' },
+  { label: 'Cross',   value: 'cross' },
+  { label: 'Slide',   value: 'slide' },
+  { label: 'Push',    value: 'push' },
+]
+
 // Format params shown on source nodes; values go into edge format (not node params)
 const FORMAT_PARAMS: ParamDef[] = [
   { key: 'res', label: 'Resolution', type: 'select', options: RESOLUTION_OPTIONS, default: '1920x1080', isFormat: true },
@@ -114,6 +128,23 @@ export const NODE_TYPES: Record<string, NodeTypeDef> = {
       { key: 'file', label: 'File', type: 'input', default: '0.ts' }
     ],
   },
+  mix: {
+    type: 'mix',
+    label: 'Mix',
+    ports: [
+      { id: 'video-in-1',  kind: 'video', direction: 'in'  },
+      { id: 'video-in-2',  kind: 'video', direction: 'in'  },
+      { id: 'audio-in-1',  kind: 'audio', direction: 'in'  },
+      { id: 'audio-in-2',  kind: 'audio', direction: 'in'  },
+      { id: 'video-out',   kind: 'video', direction: 'out' },
+      { id: 'audio-out',   kind: 'audio', direction: 'out' },
+    ],
+    params: [
+      { key: 'mode',       label: 'Mode',       type: 'select', options: MIX_MODE_OPTIONS,    default: 'fade' },
+      { key: 'transition', label: 'Transition', type: 'select', options: TRANSITION_OPTIONS,  default: 'cut' },
+      { key: 'duration',   label: 'Duration',   type: 'number', default: 500, min: 0, max: 10000 },
+    ],
+  },
 }
 
 // Default params for a new node of the given type