Merge pull request #184 from boostcampwm-2024/feature-fe-#183

다른 사용자의 커서들을 표시

frontend/src/components/CursorView.tsx

@@ -0,0 +1,33 @@
+import { Panel } from "@xyflow/react";
+import { useReactFlow } from "@xyflow/react";
+import { type AwarenessState } from "@/hooks/useCursor";
+import Cursor from "./cursor";
+import { useMemo } from "react";
+
+interface CollaborativeCursorsProps {
+  cursors: Map<number, AwarenessState>;
+}
+
+export function CollaborativeCursors({ cursors }: CollaborativeCursorsProps) {
+  const { flowToScreenPosition } = useReactFlow();
+
+  const validCursors = useMemo(
+    () => Array.from(cursors.values()).filter((cursor) => cursor.cursor),
+    [cursors],
+  );
+
+  return (
+    <Panel>
+      {validCursors.map((cursor) => (
+        <Cursor
+          key={cursor.clientId}
+          coors={flowToScreenPosition({
+            x: cursor.cursor!.x,
+            y: cursor.cursor!.y,
+          })}
+          color={cursor.color}
+        />
+      ))}
+    </Panel>
+  );
+}

frontend/src/components/canvas/index.tsx

@@ -25,6 +25,9 @@ import { cn } from "@/lib/utils";
 import { useQueryClient } from "@tanstack/react-query";
 import useYDocStore from "@/store/useYDocStore";
 
+import { useCollaborativeCursors } from "@/hooks/useCursor";
+import { CollaborativeCursors } from "../CursorView";
+
 const proOptions = { hideAttribution: true };
 
 interface CanvasProps {
@@ -39,6 +42,12 @@ function Flow({ className }: CanvasProps) {
 
   const { ydoc } = useYDocStore();
 
+  const { cursors, handleMouseMove, handleNodeDrag, handleMouseLeave } =
+    useCollaborativeCursors({
+      ydoc,
+      roomName: "flow-room",
+    });
+
   const provider = useRef<WebsocketProvider>();
   const existingPageIds = useRef(new Set<string>());
 
@@ -214,12 +223,14 @@ function Flow({ className }: CanvasProps) {
   const nodeTypes = useMemo(() => ({ note: NoteNode }), []);
 
   return (
-    <div className={cn("", className)}>
+    <div className={cn("", className)} onMouseMove={handleMouseMove}>
       <ReactFlow
         nodes={nodes}
         edges={edges}
         onNodesChange={handleNodesChange}
         onEdgesChange={handleEdgesChange}
+        onMouseLeave={handleMouseLeave}
+        onNodeDrag={handleNodeDrag}
         onConnect={onConnect}
         proOptions={proOptions}
         nodeTypes={nodeTypes}
@@ -229,6 +240,7 @@ function Flow({ className }: CanvasProps) {
         <Controls />
         <MiniMap />
         <Background variant={BackgroundVariant.Dots} gap={12} size={1} />
+        <CollaborativeCursors cursors={cursors} />
       </ReactFlow>
     </div>
   );

frontend/src/components/cursor/index.tsx

@@ -32,7 +32,7 @@ export default function Cursor({ coors, color = "#ffb8b9" }: CursorProps) {
           d="M2.40255 5.31234C1.90848 3.6645 3.58743 2.20312 5.15139 2.91972L90.0649 41.8264C91.7151 42.5825 91.5858 44.9688 89.8637 45.5422L54.7989 57.2186C53.3211 57.7107 52.0926 58.7582 51.3731 60.1397L33.0019 95.4124C32.1726 97.0047 29.8279 96.7826 29.3124 95.063L2.40255 5.31234Z"
           fill={color}
           stroke="black"
-          stroke-width="4"
+          strokeWidth="4"
         />
       </svg>
     </motion.div>

frontend/src/hooks/useCursor.ts

@@ -0,0 +1,115 @@
+import { useReactFlow, type XYPosition } from "@xyflow/react";
+import * as Y from "yjs";
+import { useCallback, useEffect, useRef, useState } from "react";
+import { WebsocketProvider } from "y-websocket";
+
+const CURSOR_COLORS = [
+  "#7d7b94",
+  "#41c76d",
+  "#f86e7e",
+  "#f6b8b8",
+  "#f7d353",
+  "#3b5bf7",
+  "#59cbf7",
+] as const;
+
+export interface AwarenessState {
+  cursor: XYPosition | null;
+  color: string;
+  clientId: number;
+}
+
+interface CollaborativeCursorsProps {
+  ydoc: Y.Doc;
+  roomName?: string;
+}
+
+export function useCollaborativeCursors({
+  ydoc,
+  roomName = "cursor-room",
+}: CollaborativeCursorsProps) {
+  const flowInstance = useReactFlow();
+  const provider = useRef<WebsocketProvider>();
+  const [cursors, setCursors] = useState<Map<number, AwarenessState>>(
+    new Map(),
+  );
+  const clientId = useRef<number | null>(null);
+  const userColor = useRef(
+    CURSOR_COLORS[Math.floor(Math.random() * CURSOR_COLORS.length)],
+  );
+
+  useEffect(() => {
+    const wsProvider = new WebsocketProvider(
+      import.meta.env.VITE_WS_URL,
+      roomName,
+      ydoc,
+    );
+
+    provider.current = wsProvider;
+    clientId.current = wsProvider.awareness.clientID;
+
+    wsProvider.awareness.setLocalState({
+      cursor: null,
+      color: userColor.current,
+      clientId: wsProvider.awareness.clientID,
+    });
+
+    wsProvider.awareness.on("change", () => {
+      const states = new Map(
+        Array.from(
+          wsProvider.awareness.getStates() as Map<number, AwarenessState>,
+        ).filter(
+          ([key, state]) => key !== clientId.current && state.cursor !== null,
+        ),
+      );
+      setCursors(states);
+    });
+
+    return () => {
+      wsProvider.destroy();
+    };
+  }, [ydoc, roomName]);
+
+  const updateCursorPosition = useCallback(
+    (x: number | null, y: number | null) => {
+      if (!provider.current?.awareness) return;
+
+      const cursor =
+        x !== null && y !== null
+          ? flowInstance?.screenToFlowPosition({ x, y })
+          : null;
+
+      provider.current.awareness.setLocalState({
+        cursor,
+        color: userColor.current,
+        clientId: provider.current.awareness.clientID,
+      });
+    },
+    [flowInstance],
+  );
+
+  const handleMouseMove = useCallback(
+    (e: React.MouseEvent) => {
+      updateCursorPosition(e.clientX, e.clientY);
+    },
+    [updateCursorPosition],
+  );
+
+  const handleNodeDrag = useCallback(
+    (e: React.MouseEvent) => {
+      updateCursorPosition(e.clientX, e.clientY);
+    },
+    [updateCursorPosition],
+  );
+
+  const handleMouseLeave = useCallback(() => {
+    updateCursorPosition(null, null);
+  }, [updateCursorPosition]);
+
+  return {
+    cursors,
+    handleMouseMove,
+    handleNodeDrag,
+    handleMouseLeave,
+  };
+}