feat(svelte): add useHandleConnections, useNodesData and useUpdateNodeData

packages/svelte/src/lib/hooks/useHandleConnections.ts

@@ -0,0 +1,30 @@
+import { derived } from 'svelte/store';
+import { areConnectionMapsEqual, type Connection, type HandleType } from '@xyflow/system';
+
+import { useStore } from '$lib/store';
+
+export type useHandleConnectionsParams = {
+  nodeId: string;
+  type: HandleType;
+  id?: string | null;
+};
+
+const initialConnections: Connection[] = [];
+
+export function useHandleConnections({ nodeId, type, id = null }: useHandleConnectionsParams) {
+  const { edges, connectionLookup } = useStore();
+  let prevConnections: Map<string, Connection> | undefined = undefined;
+
+  return derived(
+    [edges, connectionLookup],
+    ([, connectionLookup], set) => {
+      const nextConnections = connectionLookup.get(`${nodeId}-${type}-${id || null}`);
+
+      if (!areConnectionMapsEqual(nextConnections, prevConnections)) {
+        prevConnections = nextConnections;
+        set(Array.from(prevConnections?.values() || []));
+      }
+    },
+    initialConnections
+  );
+}

packages/svelte/src/lib/hooks/useNodesData.ts

@@ -0,0 +1,64 @@
+import { derived, type Readable } from 'svelte/store';
+
+import type { Node } from '$lib/types';
+import { useStore } from '$lib/store';
+
+function areNodesDataEqual(a: Node['data'][] | null, b: Node['data'][] | null) {
+  if ((!a && !b) || (!a?.length && !b?.length)) {
+    true;
+  }
+
+  if (!a || !b || a.length !== b.length) {
+    return false;
+  }
+
+  for (let i = 0; i < a.length; i++) {
+    if (a[i] !== b[i]) {
+      return false;
+    }
+  }
+
+  return true;
+}
+
+export function useNodesData<NodeType extends Node = Node>(
+  nodeId: string
+): Readable<NodeType['data'] | null>;
+export function useNodesData<NodeType extends Node = Node>(
+  nodeIds: string[]
+): Readable<NodeType['data'][]>;
+export function useNodesData<NodeType extends Node = Node>(
+  nodeIds: string[],
+  guard: (node: Node) => node is NodeType
+): Readable<NodeType['data'][]>;
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+export function useNodesData(nodeIds: any): any {
+  const { nodes, nodeLookup } = useStore();
+  let prevNodesData: (Node['data'] | null)[] | null = null;
+
+  return derived([nodes, nodeLookup], ([, nodeLookup], set) => {
+    let nextNodesData: (Node['data'] | null)[] | null = null;
+    const nodeIdArray = Array.isArray(nodeIds);
+
+    if (!nodeIdArray) {
+      nextNodesData = [nodeLookup.get(nodeIds)?.data || null];
+    } else {
+      const data = [];
+
+      for (const nodeId of nodeIds) {
+        const nodeData = nodeLookup.get(nodeId)?.data;
+
+        if (nodeData) {
+          data.push(nodeData);
+        }
+      }
+
+      nextNodesData = data;
+    }
+
+    if (!areNodesDataEqual(nextNodesData, prevNodesData)) {
+      prevNodesData = nextNodesData;
+      set(nodeIdArray ? nextNodesData : nextNodesData[0]);
+    }
+  });
+}

packages/svelte/src/lib/hooks/useUpdateNodeData.ts

@@ -0,0 +1,22 @@
+import { useStore } from '$lib/store';
+
+export function useUpdateNodeData(): (id: string, data: unknown) => void {
+  const { nodes } = useStore();
+
+  const updateNodeData = (id: string, data: unknown) => {
+    nodes.update((nds) =>
+      nds.map((node) => {
+        if (node.id === id) {
+          return {
+            ...node,
+            data
+          };
+        }
+
+        return node;
+      })
+    );
+  };
+
+  return updateNodeData;
+}