refactor: move element resize logic to react hook

apps/web/src/components/editor/timeline-element.tsx

@@ -17,7 +17,8 @@ import { useTimelineStore } from "@/stores/timeline-store";
 import { usePlaybackStore } from "@/stores/playback-store";
 import AudioWaveform from "./audio-waveform";
 import { toast } from "sonner";
-import { TimelineElementProps, ResizeState, TrackType } from "@/types/timeline";
+import { TimelineElementProps, TrackType } from "@/types/timeline";
+import { useTimelineElementResize } from "@/hooks/use-timeline-element-resize";
 import {
   DropdownMenu,
   DropdownMenuContent,
@@ -49,9 +50,21 @@ export function TimelineElement({
   } = useTimelineStore();
   const { currentTime } = usePlaybackStore();
 
-  const [resizing, setResizing] = useState<ResizeState | null>(null);
   const [elementMenuOpen, setElementMenuOpen] = useState(false);
 
+  const {
+    resizing,
+    isResizing,
+    handleResizeStart,
+    handleResizeMove,
+    handleResizeEnd,
+  } = useTimelineElementResize({
+    element,
+    track,
+    zoomLevel,
+    onUpdateTrim: updateElementTrim,
+  });
+
   const effectiveDuration =
     element.duration - element.trimStart - element.trimEnd;
   const elementWidth = Math.max(80, effectiveDuration * 50 * zoomLevel);
@@ -77,59 +90,6 @@ export function TimelineElement({
     }
   };
 
-  // Resize handles for trimming elements
-  const handleResizeStart = (
-    e: React.MouseEvent,
-    elementId: string,
-    side: "left" | "right"
-  ) => {
-    e.stopPropagation();
-    e.preventDefault();
-
-    setResizing({
-      elementId,
-      side,
-      startX: e.clientX,
-      initialTrimStart: element.trimStart,
-      initialTrimEnd: element.trimEnd,
-    });
-  };
-
-  const updateTrimFromMouseMove = (e: { clientX: number }) => {
-    if (!resizing) return;
-
-    const deltaX = e.clientX - resizing.startX;
-    const deltaTime = deltaX / (50 * zoomLevel);
-
-    if (resizing.side === "left") {
-      const newTrimStart = Math.max(
-        0,
-        Math.min(
-          element.duration - element.trimEnd - 0.1,
-          resizing.initialTrimStart + deltaTime
-        )
-      );
-      updateElementTrim(track.id, element.id, newTrimStart, element.trimEnd);
-    } else {
-      const newTrimEnd = Math.max(
-        0,
-        Math.min(
-          element.duration - element.trimStart - 0.1,
-          resizing.initialTrimEnd - deltaTime
-        )
-      );
-      updateElementTrim(track.id, element.id, element.trimStart, newTrimEnd);
-    }
-  };
-
-  const handleResizeMove = (e: React.MouseEvent) => {
-    updateTrimFromMouseMove(e);
-  };
-
-  const handleResizeEnd = () => {
-    setResizing(null);
-  };
-
   const handleDeleteElement = () => {
     removeElementFromTrack(track.id, element.id);
     setElementMenuOpen(false);

apps/web/src/hooks/use-timeline-element-resize.ts

@@ -0,0 +1,83 @@
+import { useState } from "react";
+import { ResizeState, TimelineElement, TimelineTrack } from "@/types/timeline";
+
+interface UseTimelineElementResizeProps {
+  element: TimelineElement;
+  track: TimelineTrack;
+  zoomLevel: number;
+  onUpdateTrim: (
+    trackId: string,
+    elementId: string,
+    trimStart: number,
+    trimEnd: number
+  ) => void;
+}
+
+export function useTimelineElementResize({
+  element,
+  track,
+  zoomLevel,
+  onUpdateTrim,
+}: UseTimelineElementResizeProps) {
+  const [resizing, setResizing] = useState<ResizeState | null>(null);
+
+  const handleResizeStart = (
+    e: React.MouseEvent,
+    elementId: string,
+    side: "left" | "right"
+  ) => {
+    e.stopPropagation();
+    e.preventDefault();
+
+    setResizing({
+      elementId,
+      side,
+      startX: e.clientX,
+      initialTrimStart: element.trimStart,
+      initialTrimEnd: element.trimEnd,
+    });
+  };
+
+  const updateTrimFromMouseMove = (e: { clientX: number }) => {
+    if (!resizing) return;
+
+    const deltaX = e.clientX - resizing.startX;
+    const deltaTime = deltaX / (50 * zoomLevel);
+
+    if (resizing.side === "left") {
+      const newTrimStart = Math.max(
+        0,
+        Math.min(
+          element.duration - element.trimEnd - 0.1,
+          resizing.initialTrimStart + deltaTime
+        )
+      );
+      onUpdateTrim(track.id, element.id, newTrimStart, element.trimEnd);
+    } else {
+      const newTrimEnd = Math.max(
+        0,
+        Math.min(
+          element.duration - element.trimStart - 0.1,
+          resizing.initialTrimEnd - deltaTime
+        )
+      );
+      onUpdateTrim(track.id, element.id, element.trimStart, newTrimEnd);
+    }
+  };
+
+  const handleResizeMove = (e: React.MouseEvent) => {
+    updateTrimFromMouseMove(e);
+  };
+
+  const handleResizeEnd = () => {
+    setResizing(null);
+  };
+
+  return {
+    resizing,
+    isResizing: resizing !== null,
+    handleResizeStart,
+    handleResizeMove,
+    handleResizeEnd,
+  };
+}