2 files changed, 100 insertions, 8 deletions
diff --git a/apps/web/src/lib/timeline.ts b/apps/web/src/lib/timeline.ts
new file mode 100644
index 00000000..531defac
--- /dev/null
+++ b/apps/web/src/lib/timeline.ts
@@ -0,0 +1,54 @@
+import { TimelineElement } from "@/types/timeline";
+
+// Helper function to check for element overlaps and prevent invalid timeline states
+export const checkElementOverlaps = (elements: TimelineElement[]): boolean => {
+  // Sort elements by start time
+  const sortedElements = [...elements].sort(
+    (a, b) => a.startTime - b.startTime
+  );
+
+  for (let i = 0; i < sortedElements.length - 1; i++) {
+    const current = sortedElements[i];
+    const next = sortedElements[i + 1];
+
+    const currentEnd =
+      current.startTime +
+      (current.duration - current.trimStart - current.trimEnd);
+
+    // Check if current element overlaps with next element
+    if (currentEnd > next.startTime) return true; // Overlap detected
+  }
+
+  return false; // No overlaps
+};
+
+// Helper function to resolve overlaps by adjusting element positions
+export const resolveElementOverlaps = (
+  elements: TimelineElement[]
+): TimelineElement[] => {
+  // Sort elements by start time
+  const sortedElements = [...elements].sort(
+    (a, b) => a.startTime - b.startTime
+  );
+  const resolvedElements: TimelineElement[] = [];
+
+  for (let i = 0; i < sortedElements.length; i++) {
+    const current = { ...sortedElements[i] };
+
+    if (resolvedElements.length > 0) {
+      const previous = resolvedElements[resolvedElements.length - 1];
+      const previousEnd =
+        previous.startTime +
+        (previous.duration - previous.trimStart - previous.trimEnd);
+
+      // If current element would overlap with previous, push it after previous ends
+      if (current.startTime < previousEnd) {
+        current.startTime = previousEnd;
+      }
+    }
+
+    resolvedElements.push(current);
+  }
+
+  return resolvedElements;
+};
diff --git a/apps/web/src/lib/utils.ts b/apps/web/src/lib/utils.ts
index dd73059f..8d2ee03a 100644
--- a/apps/web/src/lib/utils.ts
+++ b/apps/web/src/lib/utils.ts
@@ -13,7 +13,10 @@ export function cn(...inputs: ClassValue[]) {
  */
 export function generateUUID(): string {
   // Use the native crypto.randomUUID if available
-  if (typeof crypto !== 'undefined' && typeof crypto.randomUUID === 'function') {
+  if (
+    typeof crypto !== "undefined" &&
+    typeof crypto.randomUUID === "function"
+  ) {
     return crypto.randomUUID();
   }
 
@@ -26,13 +29,48 @@ export function generateUUID(): string {
   // Set variant 10xxxxxx
   bytes[8] = (bytes[8] & 0x3f) | 0x80;
 
-  const hex = [...bytes].map(b => b.toString(16).padStart(2, '0'));
+  const hex = [...bytes].map((b) => b.toString(16).padStart(2, "0"));
 
   return (
-    hex.slice(0, 4).join('') + '-' +
-    hex.slice(4, 6).join('') + '-' +
-    hex.slice(6, 8).join('') + '-' +
-    hex.slice(8, 10).join('') + '-' +
-    hex.slice(10, 16).join('')
+    hex.slice(0, 4).join("") +
+    "-" +
+    hex.slice(4, 6).join("") +
+    "-" +
+    hex.slice(6, 8).join("") +
+    "-" +
+    hex.slice(8, 10).join("") +
+    "-" +
+    hex.slice(10, 16).join("")
   );
-}
-\ No newline at end of file
+}
+
+export function isDOMElement(el: any): el is HTMLElement {
+  return !!el && (el instanceof Element || el instanceof HTMLElement);
+}
+
+export function isTypableElement(el: HTMLElement): boolean {
+  // If content editable, then it is editable
+  if (el.isContentEditable) return true;
+
+  // If element is an input and the input is enabled, then it is typable
+  if (el.tagName === "INPUT") {
+    return !(el as HTMLInputElement).disabled;
+  }
+  // If element is a textarea and the input is enabled, then it is typable
+  if (el.tagName === "TEXTAREA") {
+    return !(el as HTMLTextAreaElement).disabled;
+  }
+
+  return false;
+}
+export function isAppleDevice() {
+  return /(Mac|iPhone|iPod|iPad)/i.test(navigator.platform);
+}
+
+export function getPlatformSpecialKey() {
+  return isAppleDevice() ? "⌘" : "Ctrl";
+}
+
+export function getPlatformAlternateKey() {
+  return isAppleDevice() ? "⌥" : "Alt";
+}