feat: implemented editable automation lane in piano roll window

src/components/piano-roll/pianoRollSnap.ts

@@ -0,0 +1,53 @@
+import { DEBUG_MODE } from '../../constants';
+
+export function getSnapStep(currentSnap: string): number | null {
+  if (currentSnap === 'NO SNAP') {
+    return null;
+  }
+
+  const denominator = parseInt(currentSnap.split('/')[1], 10);
+  if (Number.isNaN(denominator)) {
+    return null;
+  }
+
+  return 4 / denominator;
+}
+
+export function getSnappedBeatPosition(
+  beatPosition: number,
+  currentSnap: string,
+  useFloorSnapping: boolean = false,
+): number {
+  const snapStep = getSnapStep(currentSnap);
+  if (snapStep === null) {
+    return beatPosition;
+  }
+
+  const snappedPosition = useFloorSnapping
+    ? Math.floor(beatPosition / snapStep) * snapStep
+    : Math.round(beatPosition / snapStep) * snapStep;
+
+  if (DEBUG_MODE.PIANO_ROLL) {
+    console.log(
+      `Snapping (${useFloorSnapping ? 'floor' : 'round'}): ${beatPosition} -> ${snappedPosition} (snap: ${currentSnap}, step: ${snapStep})`,
+    );
+  }
+
+  return snappedPosition;
+}
+
+export function getSnappedLength(length: number, currentSnap: string, minimumLength: number): number {
+  const snapStep = getSnapStep(currentSnap);
+  if (snapStep === null) {
+    return length;
+  }
+
+  const snappedLength = Math.round(length / snapStep) * snapStep;
+  const finalLength = Math.max(minimumLength, snappedLength);
+
+  if (DEBUG_MODE.PIANO_ROLL) {
+    console.log(`Length snapping: ${length} -> ${finalLength} (snap: ${currentSnap}, step: ${snapStep})`);
+  }
+
+  return finalLength;
+}