feat(quick-004): add easeCurve handle type and wire up connection routing

- Add inheritedFrom field to EaseCurveNodeData interface
- Add easeCurve to HandleType union
- Update getHandleType, getNodeHandles, isValidConnection for easeCurve
- Add easeCurve extraction in getConnectedInputs
- Propagate parent bezierHandles/easingPreset in both execution paths
- Fix validation.ts default data for easeCurve node

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/components/ConnectionDropMenu.tsx

@@ -298,7 +298,7 @@ const AUDIO_SOURCE_OPTIONS: MenuOption[] = [
 
 interface ConnectionDropMenuProps {
   position: { x: number; y: number };
-  handleType: "image" | "text" | "video" | "audio" | null;
+  handleType: "image" | "text" | "video" | "audio" | "easeCurve" | null;
   connectionType: "source" | "target"; // source = dragging from output, target = dragging from input
   onSelect: (selection: { type: NodeType | MenuAction; isAction: boolean }) => void;
   onClose: () => void;

src/components/WorkflowCanvas.tsx

@@ -78,8 +78,10 @@ const edgeTypes: EdgeTypes = {
 // - Video handles can only connect to generateVideo or output nodes
 // Helper to determine handle type from handle ID
 // For dynamic handles, we use naming convention: image inputs contain "image", text inputs are "prompt" or "negative_prompt"
-const getHandleType = (handleId: string | null | undefined): "image" | "text" | "video" | "audio" | null => {
+const getHandleType = (handleId: string | null | undefined): "image" | "text" | "video" | "audio" | "easeCurve" | null => {
   if (!handleId) return null;
+  // EaseCurve handles (must check before other types)
+  if (handleId === "easeCurve") return "easeCurve";
   // Standard handles
   if (handleId === "video") return "video";
   if (handleId === "audio" || handleId.startsWith("audio")) return "audio";
@@ -121,7 +123,7 @@ const getNodeHandles = (nodeType: string): { inputs: string[]; outputs: string[]
     case "videoStitch":
       return { inputs: ["video", "audio"], outputs: ["video"] };
     case "easeCurve":
-      return { inputs: ["video"], outputs: ["video"] };
+      return { inputs: ["video", "easeCurve"], outputs: ["video", "easeCurve"] };
     default:
       return { inputs: [], outputs: [] };
   }
@@ -130,7 +132,7 @@ const getNodeHandles = (nodeType: string): { inputs: string[]; outputs: string[]
 interface ConnectionDropState {
   position: { x: number; y: number };
   flowPosition: { x: number; y: number };
-  handleType: "image" | "text" | "video" | "audio" | null;
+  handleType: "image" | "text" | "video" | "audio" | "easeCurve" | null;
   connectionType: "source" | "target";
   sourceNodeId: string | null;
   sourceHandleId: string | null;
@@ -294,6 +296,13 @@ export function WorkflowCanvas() {
       // If we can't determine types, allow the connection
       if (!sourceType || !targetType) return true;
 
+      // EaseCurve connections: only between easeCurve nodes
+      if (sourceType === "easeCurve" || targetType === "easeCurve") {
+        if (sourceType !== "easeCurve" || targetType !== "easeCurve") return false;
+        const targetNode = nodes.find((n) => n.id === connection.target);
+        return targetNode?.type === "easeCurve";
+      }
+
       // Video connections have special rules
       if (sourceType === "video") {
         // Video source can ONLY connect to:
@@ -406,7 +415,7 @@ export function WorkflowCanvas() {
       // Helper to find a compatible handle on a node by type
       const findCompatibleHandle = (
         node: Node,
-        handleType: "image" | "text" | "video" | "audio",
+        handleType: "image" | "text" | "video" | "audio" | "easeCurve",
         needInput: boolean
       ): string | null => {
         // Check for dynamic inputSchema first
@@ -781,6 +790,11 @@ export function WorkflowCanvas() {
           // VideoStitch accepts audio
           targetHandleId = "audio";
         }
+      } else if (handleType === "easeCurve") {
+        if (nodeType === "easeCurve") {
+          targetHandleId = "easeCurve";
+          sourceHandleIdForNewNode = "easeCurve";
+        }
       }
 
       // Get all selected nodes to connect them all to the new node
@@ -1544,7 +1558,7 @@ export function WorkflowCanvas() {
               case "videoStitch":
                 return "#f97316";
               case "easeCurve":
-                return "#f59e0b"; // amber-500
+                return "#bef264"; // lime-300 (easy-peasy-ease)
               default:
                 return "#94a3b8";
             }

src/lib/quickstart/validation.ts

@@ -306,6 +306,7 @@ function createDefaultNodeData(type: NodeType): WorkflowNodeData {
       return {
         bezierHandles: [0.445, 0.05, 0.55, 0.95] as [number, number, number, number],
         easingPreset: "easeInOutSine",
+        inheritedFrom: null,
         outputDuration: 1.5,
         outputVideo: null,
         status: "idle",

src/store/utils/nodeDefaults.ts

@@ -204,6 +204,7 @@ export const createDefaultNodeData = (type: NodeType): WorkflowNodeData => {
       return {
         bezierHandles: [0.445, 0.05, 0.55, 0.95], // easeInOutSine preset
         easingPreset: "easeInOutSine",
+        inheritedFrom: null,
         outputDuration: 1.5,
         outputVideo: null,
         status: "idle",

src/store/workflowStore.ts

@@ -138,7 +138,7 @@ interface WorkflowStore {
 
   // Helpers
   getNodeById: (id: string) => WorkflowNode | undefined;
-  getConnectedInputs: (nodeId: string) => { images: string[]; videos: string[]; audio: string[]; text: string | null; dynamicInputs: Record<string, string | string[]> };
+  getConnectedInputs: (nodeId: string) => { images: string[]; videos: string[]; audio: string[]; text: string | null; dynamicInputs: Record<string, string | string[]>; easeCurve: { bezierHandles: [number, number, number, number]; easingPreset: string | null } | null };
   validateWorkflow: () => { valid: boolean; errors: string[] };
 
   // Global Image History
@@ -868,7 +868,23 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
         }
       });
 
-    return { images, videos, audio, text, dynamicInputs };
+    // Extract easeCurve data from parent EaseCurve node
+    let easeCurve: { bezierHandles: [number, number, number, number]; easingPreset: string | null } | null = null;
+    const easeCurveEdge = edges.find(
+      (e) => e.target === nodeId && e.targetHandle === "easeCurve"
+    );
+    if (easeCurveEdge) {
+      const sourceNode = nodes.find((n) => n.id === easeCurveEdge.source);
+      if (sourceNode?.type === "easeCurve") {
+        const sourceData = sourceNode.data as EaseCurveNodeData;
+        easeCurve = {
+          bezierHandles: sourceData.bezierHandles,
+          easingPreset: sourceData.easingPreset,
+        };
+      }
+    }
+
+    return { images, videos, audio, text, dynamicInputs, easeCurve };
   },
 
   validateWorkflow: () => {
@@ -1985,6 +2001,22 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
             try {
               const inputs = getConnectedInputs(node.id);
 
+              // Propagate parent easeCurve settings if inherited
+              let activeBezierHandles = nodeData.bezierHandles;
+              let activeEasingPreset = nodeData.easingPreset;
+              if (inputs.easeCurve) {
+                activeBezierHandles = inputs.easeCurve.bezierHandles;
+                activeEasingPreset = inputs.easeCurve.easingPreset;
+                const easeCurveSourceId = edges.filter(
+                  (e) => e.target === node.id && e.targetHandle === "easeCurve"
+                )[0]?.source ?? null;
+                updateNodeData(node.id, {
+                  bezierHandles: activeBezierHandles,
+                  easingPreset: activeEasingPreset,
+                  inheritedFrom: easeCurveSourceId,
+                });
+              }
+
               if (inputs.videos.length === 0) {
                 updateNodeData(node.id, {
                   status: "error",
@@ -2015,15 +2047,15 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
 
               // Determine easing function: use named preset if set, otherwise create from Bezier handles
               let easingFunction: string | ((t: number) => number);
-              if (nodeData.easingPreset) {
+              if (activeEasingPreset) {
-                easingFunction = nodeData.easingPreset;
+                easingFunction = activeEasingPreset;
               } else {
                 const { createBezierEasing } = await import('@/lib/easing-functions');
                 easingFunction = createBezierEasing(
-                  nodeData.bezierHandles[0],
+                  activeBezierHandles[0],
-                  nodeData.bezierHandles[1],
+                  activeBezierHandles[1],
-                  nodeData.bezierHandles[2],
+                  activeBezierHandles[2],
-                  nodeData.bezierHandles[3]
+                  activeBezierHandles[3]
                 );
               }
 
@@ -2783,6 +2815,23 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
         try {
           const inputs = getConnectedInputs(nodeId);
 
+          // Propagate parent easeCurve settings if inherited
+          let activeBezierHandles = nodeData.bezierHandles;
+          let activeEasingPreset = nodeData.easingPreset;
+          if (inputs.easeCurve) {
+            activeBezierHandles = inputs.easeCurve.bezierHandles;
+            activeEasingPreset = inputs.easeCurve.easingPreset;
+            const { edges } = get();
+            const easeCurveSourceId = edges.filter(
+              (e) => e.target === nodeId && e.targetHandle === "easeCurve"
+            )[0]?.source ?? null;
+            updateNodeData(nodeId, {
+              bezierHandles: activeBezierHandles,
+              easingPreset: activeEasingPreset,
+              inheritedFrom: easeCurveSourceId,
+            });
+          }
+
           if (inputs.videos.length === 0) {
             updateNodeData(nodeId, {
               status: "error",
@@ -2812,15 +2861,15 @@ export const useWorkflowStore = create<WorkflowStore>((set, get) => ({
           });
 
           let easingFunction: string | ((t: number) => number);
-          if (nodeData.easingPreset) {
+          if (activeEasingPreset) {
-            easingFunction = nodeData.easingPreset;
+            easingFunction = activeEasingPreset;
           } else {
             const { createBezierEasing } = await import('@/lib/easing-functions');
             easingFunction = createBezierEasing(
-              nodeData.bezierHandles[0],
+              activeBezierHandles[0],
-              nodeData.bezierHandles[1],
+              activeBezierHandles[1],
-              nodeData.bezierHandles[2],
+              activeBezierHandles[2],
-              nodeData.bezierHandles[3]
+              activeBezierHandles[3]
             );
           }
 

src/types/nodes.ts

@@ -245,6 +245,7 @@ export interface VideoStitchNodeData extends BaseNodeData {
 export interface EaseCurveNodeData extends BaseNodeData {
   bezierHandles: [number, number, number, number];
   easingPreset: string | null;
+  inheritedFrom: string | null;
   outputDuration: number;
   outputVideo: string | null;
   status: NodeStatus;
@@ -308,7 +309,7 @@ export type WorkflowNode = Node<WorkflowNodeData, NodeType> & {
 /**
  * Handle types for node connections
  */
-export type HandleType = "image" | "text" | "audio" | "video";
+export type HandleType = "image" | "text" | "audio" | "video" | "easeCurve";
 
 /**
  * Default settings for node types - stored in localStorage