refactor all timeline components

1 files changed, 1097 insertions, 0 deletions

diff --git a/apps/web/src/components/editor/timeline/timeline-track.tsx b/apps/web/src/components/editor/timeline/timeline-track.tsx
new file mode 100644
index 00000000..523a9f54
--- /dev/null
+++ b/apps/web/src/components/editor/timeline/timeline-track.tsx
@@ -0,0 +1,1097 @@
+"use client";
+
+import { useRef, useState, useEffect } from "react";
+import { useTimelineStore } from "@/stores/timeline-store";
+import { useMediaStore } from "@/stores/media-store";
+import { toast } from "sonner";
+import { TimelineElement } from "./timeline-element";
+import {
+  TimelineTrack,
+  getMainTrack,
+  canElementGoOnTrack,
+} from "@/types/timeline";
+import { usePlaybackStore } from "@/stores/playback-store";
+import type {
+  TimelineElement as TimelineElementType,
+  DragData,
+} from "@/types/timeline";
+import {
+  snapTimeToFrame,
+  TIMELINE_CONSTANTS,
+} from "@/constants/timeline-constants";
+import { useProjectStore } from "@/stores/project-store";
+import { useTimelineSnapping, SnapPoint } from "@/hooks/use-timeline-snapping";
+
+export function TimelineTrackContent({
+  track,
+  zoomLevel,
+  onSnapPointChange,
+}: {
+  track: TimelineTrack;
+  zoomLevel: number;
+  onSnapPointChange?: (snapPoint: SnapPoint | null) => void;
+}) {
+  const { mediaItems } = useMediaStore();
+  const {
+    tracks,
+    addTrack,
+    moveElementToTrack,
+    updateElementStartTime,
+    addElementToTrack,
+    selectedElements,
+    selectElement,
+    dragState,
+    startDrag: startDragAction,
+    updateDragTime,
+    endDrag: endDragAction,
+    clearSelectedElements,
+    insertTrackAt,
+    snappingEnabled,
+  } = useTimelineStore();
+
+  const { currentTime } = usePlaybackStore();
+
+  // Initialize snapping hook
+  const { snapElementEdge } = useTimelineSnapping({
+    snapThreshold: 10,
+    enableElementSnapping: snappingEnabled,
+    enablePlayheadSnapping: snappingEnabled,
+  });
+
+  // Helper function for drop snapping that tries both edges
+  const getDropSnappedTime = (
+    dropTime: number,
+    elementDuration: number,
+    excludeElementId?: string
+  ) => {
+    if (!snappingEnabled) {
+      // Use frame snapping if project has FPS, otherwise use decimal snapping
+      const projectStore = useProjectStore.getState();
+      const projectFps = projectStore.activeProject?.fps || 30;
+      return snapTimeToFrame(dropTime, projectFps);
+    }
+
+    // Try snapping both start and end edges for drops
+    const startSnapResult = snapElementEdge(
+      dropTime,
+      elementDuration,
+      tracks,
+      currentTime,
+      zoomLevel,
+      excludeElementId,
+      true // snap to start edge
+    );
+
+    const endSnapResult = snapElementEdge(
+      dropTime,
+      elementDuration,
+      tracks,
+      currentTime,
+      zoomLevel,
+      excludeElementId,
+      false // snap to end edge
+    );
+
+    // Choose the snap result with the smaller distance (closer snap)
+    let bestSnapResult = startSnapResult;
+    if (
+      endSnapResult.snapPoint &&
+      (!startSnapResult.snapPoint ||
+        endSnapResult.snapDistance < startSnapResult.snapDistance)
+    ) {
+      bestSnapResult = endSnapResult;
+    }
+
+    return bestSnapResult.snappedTime;
+  };
+
+  const timelineRef = useRef<HTMLDivElement>(null);
+  const [isDropping, setIsDropping] = useState(false);
+  const [dropPosition, setDropPosition] = useState<number | null>(null);
+  const [wouldOverlap, setWouldOverlap] = useState(false);
+  const dragCounterRef = useRef(0);
+  const [mouseDownLocation, setMouseDownLocation] = useState<{
+    x: number;
+    y: number;
+  } | null>(null);
+
+  // Set up mouse event listeners for drag
+  useEffect(() => {
+    if (!dragState.isDragging) return;
+
+    const handleMouseMove = (e: MouseEvent) => {
+      if (!timelineRef.current) return;
+
+      // On first mouse move during drag, ensure the element is selected
+      if (dragState.elementId && dragState.trackId) {
+        const isSelected = selectedElements.some(
+          (c) =>
+            c.trackId === dragState.trackId &&
+            c.elementId === dragState.elementId
+        );
+
+        if (!isSelected) {
+          // Select this element (replacing other selections) since we're dragging it
+          selectElement(dragState.trackId, dragState.elementId, false);
+        }
+      }
+
+      const timelineRect = timelineRef.current.getBoundingClientRect();
+      const mouseX = e.clientX - timelineRect.left;
+      const mouseTime = Math.max(
+        0,
+        mouseX / (TIMELINE_CONSTANTS.PIXELS_PER_SECOND * zoomLevel)
+      );
+      const adjustedTime = Math.max(0, mouseTime - dragState.clickOffsetTime);
+
+      // Apply snapping if enabled
+      let finalTime = adjustedTime;
+      let snapPoint = null;
+      if (snappingEnabled) {
+        // Find the element being dragged to get its duration
+        let elementDuration = 5; // fallback duration
+        if (dragState.elementId && dragState.trackId) {
+          const sourceTrack = tracks.find((t) => t.id === dragState.trackId);
+          const element = sourceTrack?.elements.find(
+            (e) => e.id === dragState.elementId
+          );
+          if (element) {
+            elementDuration =
+              element.duration - element.trimStart - element.trimEnd;
+          }
+        }
+
+        // Try snapping both start and end edges
+        const startSnapResult = snapElementEdge(
+          adjustedTime,
+          elementDuration,
+          tracks,
+          currentTime,
+          zoomLevel,
+          dragState.elementId || undefined,
+          true // snap to start edge
+        );
+
+        const endSnapResult = snapElementEdge(
+          adjustedTime,
+          elementDuration,
+          tracks,
+          currentTime,
+          zoomLevel,
+          dragState.elementId || undefined,
+          false // snap to end edge
+        );
+
+        // Choose the snap result with the smaller distance (closer snap)
+        let bestSnapResult = startSnapResult;
+        if (
+          endSnapResult.snapPoint &&
+          (!startSnapResult.snapPoint ||
+            endSnapResult.snapDistance < startSnapResult.snapDistance)
+        ) {
+          bestSnapResult = endSnapResult;
+        }
+
+        finalTime = bestSnapResult.snappedTime;
+        snapPoint = bestSnapResult.snapPoint;
+
+        // Notify parent component about snap point change
+        onSnapPointChange?.(snapPoint);
+      } else {
+        // Use frame snapping if project has FPS, otherwise use decimal snapping
+        const projectStore = useProjectStore.getState();
+        const projectFps = projectStore.activeProject?.fps || 30;
+        finalTime = snapTimeToFrame(adjustedTime, projectFps);
+
+        // Clear snap point when not snapping
+        onSnapPointChange?.(null);
+      }
+
+      updateDragTime(finalTime);
+    };
+
+    const handleMouseUp = (e: MouseEvent) => {
+      if (!dragState.elementId || !dragState.trackId) return;
+
+      // If this track initiated the drag, we should handle the mouse up regardless of where it occurs
+      const isTrackThatStartedDrag = dragState.trackId === track.id;
+
+      const timelineRect = timelineRef.current?.getBoundingClientRect();
+      if (!timelineRect) {
+        if (isTrackThatStartedDrag) {
+          updateElementStartTime(
+            track.id,
+            dragState.elementId,
+            dragState.currentTime
+          );
+          endDragAction();
+          // Clear snap point when drag ends
+          onSnapPointChange?.(null);
+        }
+        return;
+      }
+
+      const isMouseOverThisTrack =
+        e.clientY >= timelineRect.top && e.clientY <= timelineRect.bottom;
+
+      if (!isMouseOverThisTrack && !isTrackThatStartedDrag) return;
+
+      const finalTime = dragState.currentTime;
+
+      if (isMouseOverThisTrack) {
+        const sourceTrack = tracks.find((t) => t.id === dragState.trackId);
+        const movingElement = sourceTrack?.elements.find(
+          (c) => c.id === dragState.elementId
+        );
+
+        if (movingElement) {
+          const movingElementDuration =
+            movingElement.duration -
+            movingElement.trimStart -
+            movingElement.trimEnd;
+          const movingElementEnd = finalTime + movingElementDuration;
+
+          const targetTrack = tracks.find((t) => t.id === track.id);
+          const hasOverlap = targetTrack?.elements.some((existingElement) => {
+            if (
+              dragState.trackId === track.id &&
+              existingElement.id === dragState.elementId
+            ) {
+              return false;
+            }
+            const existingStart = existingElement.startTime;
+            const existingEnd =
+              existingElement.startTime +
+              (existingElement.duration -
+                existingElement.trimStart -
+                existingElement.trimEnd);
+            return finalTime < existingEnd && movingElementEnd > existingStart;
+          });
+
+          if (!hasOverlap) {
+            if (dragState.trackId === track.id) {
+              updateElementStartTime(track.id, dragState.elementId, finalTime);
+            } else {
+              moveElementToTrack(
+                dragState.trackId,
+                track.id,
+                dragState.elementId
+              );
+              requestAnimationFrame(() => {
+                updateElementStartTime(
+                  track.id,
+                  dragState.elementId!,
+                  finalTime
+                );
+              });
+            }
+          }
+        }
+      } else if (isTrackThatStartedDrag) {
+        // Mouse is not over this track, but this track started the drag
+        // This means user released over ruler/outside - update position within same track
+        const sourceTrack = tracks.find((t) => t.id === dragState.trackId);
+        const movingElement = sourceTrack?.elements.find(
+          (c) => c.id === dragState.elementId
+        );
+
+        if (movingElement) {
+          const movingElementDuration =
+            movingElement.duration -
+            movingElement.trimStart -
+            movingElement.trimEnd;
+          const movingElementEnd = finalTime + movingElementDuration;
+
+          const hasOverlap = track.elements.some((existingElement) => {
+            if (existingElement.id === dragState.elementId) {
+              return false;
+            }
+            const existingStart = existingElement.startTime;
+            const existingEnd =
+              existingElement.startTime +
+              (existingElement.duration -
+                existingElement.trimStart -
+                existingElement.trimEnd);
+            return finalTime < existingEnd && movingElementEnd > existingStart;
+          });
+
+          if (!hasOverlap) {
+            updateElementStartTime(track.id, dragState.elementId, finalTime);
+          }
+        }
+      }
+
+      if (isTrackThatStartedDrag) {
+        endDragAction();
+        // Clear snap point when drag ends
+        onSnapPointChange?.(null);
+      }
+    };
+
+    document.addEventListener("mousemove", handleMouseMove);
+    document.addEventListener("mouseup", handleMouseUp);
+
+    return () => {
+      document.removeEventListener("mousemove", handleMouseMove);
+      document.removeEventListener("mouseup", handleMouseUp);
+    };
+  }, [
+    dragState.isDragging,
+    dragState.clickOffsetTime,
+    dragState.elementId,
+    dragState.trackId,
+    dragState.currentTime,
+    zoomLevel,
+    tracks,
+    track.id,
+    updateDragTime,
+    updateElementStartTime,
+    moveElementToTrack,
+    endDragAction,
+    selectedElements,
+    selectElement,
+    onSnapPointChange,
+  ]);
+
+  const handleElementMouseDown = (
+    e: React.MouseEvent,
+    element: TimelineElementType
+  ) => {
+    setMouseDownLocation({ x: e.clientX, y: e.clientY });
+
+    // Detect right-click (button 2) and handle selection without starting drag
+    const isRightClick = e.button === 2;
+    const isMultiSelect = e.metaKey || e.ctrlKey || e.shiftKey;
+
+    if (isRightClick) {
+      // Handle right-click selection
+      const isSelected = selectedElements.some(
+        (c) => c.trackId === track.id && c.elementId === element.id
+      );
+
+      // If element is not selected, select it (keep other selections if multi-select)
+      if (!isSelected) {
+        selectElement(track.id, element.id, isMultiSelect);
+      }
+      // If element is already selected, keep it selected
+
+      // Don't start drag action for right-clicks
+      return;
+    }
+
+    // Handle multi-selection for left-click with modifiers
+    if (isMultiSelect) {
+      selectElement(track.id, element.id, true);
+    }
+
+    // Calculate the offset from the left edge of the element to where the user clicked
+    const elementElement = e.currentTarget as HTMLElement;
+    const elementRect = elementElement.getBoundingClientRect();
+    const clickOffsetX = e.clientX - elementRect.left;
+    const clickOffsetTime =
+      clickOffsetX / (TIMELINE_CONSTANTS.PIXELS_PER_SECOND * zoomLevel);
+
+    startDragAction(
+      element.id,
+      track.id,
+      e.clientX,
+      element.startTime,
+      clickOffsetTime
+    );
+  };
+
+  const handleElementClick = (
+    e: React.MouseEvent,
+    element: TimelineElementType
+  ) => {
+    e.stopPropagation();
+
+    // Check if mouse moved significantly
+    if (mouseDownLocation) {
+      const deltaX = Math.abs(e.clientX - mouseDownLocation.x);
+      const deltaY = Math.abs(e.clientY - mouseDownLocation.y);
+      // If it moved more than a few pixels, consider it a drag and not a click.
+      if (deltaX > 5 || deltaY > 5) {
+        setMouseDownLocation(null); // Reset for next interaction
+        return;
+      }
+    }
+
+    // Skip selection logic for multi-selection (handled in mousedown)
+    if (e.metaKey || e.ctrlKey || e.shiftKey) {
+      return;
+    }
+
+    // Handle single selection
+    const isSelected = selectedElements.some(
+      (c) => c.trackId === track.id && c.elementId === element.id
+    );
+
+    if (!isSelected) {
+      // If element is not selected, select it (replacing other selections)
+      selectElement(track.id, element.id, false);
+    }
+    // If element is already selected, keep it selected (do nothing)
+  };
+
+  const handleTrackDragOver = (e: React.DragEvent) => {
+    e.preventDefault();
+
+    // Handle both timeline elements and media items
+    const hasTimelineElement = e.dataTransfer.types.includes(
+      "application/x-timeline-element"
+    );
+    const hasMediaItem = e.dataTransfer.types.includes(
+      "application/x-media-item"
+    );
+
+    if (!hasTimelineElement && !hasMediaItem) return;
+
+    // Calculate drop position for overlap checking
+    const trackContainer = e.currentTarget.querySelector(
+      ".track-elements-container"
+    ) as HTMLElement;
+    let dropTime = 0;
+    if (trackContainer) {
+      const rect = trackContainer.getBoundingClientRect();
+      const mouseX = Math.max(0, e.clientX - rect.left);
+      dropTime = mouseX / (TIMELINE_CONSTANTS.PIXELS_PER_SECOND * zoomLevel);
+    }
+
+    // Check for potential overlaps and show appropriate feedback
+    let wouldOverlap = false;
+
+    if (hasMediaItem) {
+      try {
+        const mediaItemData = e.dataTransfer.getData(
+          "application/x-media-item"
+        );
+        if (mediaItemData) {
+          const dragData: DragData = JSON.parse(mediaItemData);
+
+          if (dragData.type === "text") {
+            // Text elements have default duration of 5 seconds
+            const newElementDuration = 5;
+            const snappedTime = getDropSnappedTime(
+              dropTime,
+              newElementDuration
+            );
+            const newElementEnd = snappedTime + newElementDuration;
+
+            wouldOverlap = track.elements.some((existingElement) => {
+              const existingStart = existingElement.startTime;
+              const existingEnd =
+                existingElement.startTime +
+                (existingElement.duration -
+                  existingElement.trimStart -
+                  existingElement.trimEnd);
+              return snappedTime < existingEnd && newElementEnd > existingStart;
+            });
+          } else {
+            // Media elements
+            const mediaItem = mediaItems.find(
+              (item) => item.id === dragData.id
+            );
+            if (mediaItem) {
+              const newElementDuration = mediaItem.duration || 5;
+              const snappedTime = getDropSnappedTime(
+                dropTime,
+                newElementDuration
+              );
+              const newElementEnd = snappedTime + newElementDuration;
+
+              wouldOverlap = track.elements.some((existingElement) => {
+                const existingStart = existingElement.startTime;
+                const existingEnd =
+                  existingElement.startTime +
+                  (existingElement.duration -
+                    existingElement.trimStart -
+                    existingElement.trimEnd);
+                return (
+                  snappedTime < existingEnd && newElementEnd > existingStart
+                );
+              });
+            }
+          }
+        }
+      } catch (error) {
+        // Continue with default behavior
+      }
+    } else if (hasTimelineElement) {
+      try {
+        const timelineElementData = e.dataTransfer.getData(
+          "application/x-timeline-element"
+        );
+        if (timelineElementData) {
+          const { elementId, trackId: fromTrackId } =
+            JSON.parse(timelineElementData);
+          const sourceTrack = tracks.find(
+            (t: TimelineTrack) => t.id === fromTrackId
+          );
+          const movingElement = sourceTrack?.elements.find(
+            (c: any) => c.id === elementId
+          );
+
+          if (movingElement) {
+            const movingElementDuration =
+              movingElement.duration -
+              movingElement.trimStart -
+              movingElement.trimEnd;
+            const snappedTime = getDropSnappedTime(
+              dropTime,
+              movingElementDuration,
+              elementId
+            );
+            const movingElementEnd = snappedTime + movingElementDuration;
+
+            wouldOverlap = track.elements.some((existingElement) => {
+              if (fromTrackId === track.id && existingElement.id === elementId)
+                return false;
+
+              const existingStart = existingElement.startTime;
+              const existingEnd =
+                existingElement.startTime +
+                (existingElement.duration -
+                  existingElement.trimStart -
+                  existingElement.trimEnd);
+              return (
+                snappedTime < existingEnd && movingElementEnd > existingStart
+              );
+            });
+          }
+        }
+      } catch (error) {
+        // Continue with default behavior
+      }
+    }
+
+    if (wouldOverlap) {
+      e.dataTransfer.dropEffect = "none";
+      setWouldOverlap(true);
+      // Use default duration for position indicator
+      setDropPosition(getDropSnappedTime(dropTime, 5));
+      return;
+    }
+
+    e.dataTransfer.dropEffect = hasTimelineElement ? "move" : "copy";
+    setWouldOverlap(false);
+    // Use default duration for position indicator
+    setDropPosition(getDropSnappedTime(dropTime, 5));
+  };
+
+  const handleTrackDragEnter = (e: React.DragEvent) => {
+    e.preventDefault();
+
+    const hasTimelineElement = e.dataTransfer.types.includes(
+      "application/x-timeline-element"
+    );
+    const hasMediaItem = e.dataTransfer.types.includes(
+      "application/x-media-item"
+    );
+
+    if (!hasTimelineElement && !hasMediaItem) return;
+
+    dragCounterRef.current++;
+    setIsDropping(true);
+  };
+
+  const handleTrackDragLeave = (e: React.DragEvent) => {
+    e.preventDefault();
+
+    const hasTimelineElement = e.dataTransfer.types.includes(
+      "application/x-timeline-element"
+    );
+    const hasMediaItem = e.dataTransfer.types.includes(
+      "application/x-media-item"
+    );
+
+    if (!hasTimelineElement && !hasMediaItem) return;
+
+    dragCounterRef.current--;
+
+    if (dragCounterRef.current === 0) {
+      setIsDropping(false);
+      setWouldOverlap(false);
+      setDropPosition(null);
+    }
+  };
+
+  const handleTrackDrop = (e: React.DragEvent) => {
+    e.preventDefault();
+    e.stopPropagation();
+
+    // Debug logging
+    console.log(
+      JSON.stringify({
+        message: "Drop event started in timeline track",
+        dataTransferTypes: Array.from(e.dataTransfer.types),
+        trackId: track.id,
+        trackType: track.type,
+      })
+    );
+
+    // Reset all drag states
+    dragCounterRef.current = 0;
+    setIsDropping(false);
+    setWouldOverlap(false);
+
+    const hasTimelineElement = e.dataTransfer.types.includes(
+      "application/x-timeline-element"
+    );
+    const hasMediaItem = e.dataTransfer.types.includes(
+      "application/x-media-item"
+    );
+
+    if (!hasTimelineElement && !hasMediaItem) return;
+
+    const trackContainer = e.currentTarget.querySelector(
+      ".track-elements-container"
+    ) as HTMLElement;
+    if (!trackContainer) return;
+
+    const rect = trackContainer.getBoundingClientRect();
+    const mouseX = Math.max(0, e.clientX - rect.left);
+    const mouseY = e.clientY - rect.top; // Get Y position relative to this track
+    const newStartTime =
+      mouseX / (TIMELINE_CONSTANTS.PIXELS_PER_SECOND * zoomLevel);
+    const projectStore = useProjectStore.getState();
+    const projectFps = projectStore.activeProject?.fps || 30;
+    const snappedTime = snapTimeToFrame(newStartTime, projectFps);
+
+    // Calculate drop position relative to tracks
+    const currentTrackIndex = tracks.findIndex((t) => t.id === track.id);
+
+    // Determine drop zone within the track (top 20px, middle 20px, bottom 20px)
+    let dropPosition: "above" | "on" | "below";
+    if (mouseY < 20) {
+      dropPosition = "above";
+    } else if (mouseY > 40) {
+      dropPosition = "below";
+    } else {
+      dropPosition = "on";
+    }
+
+    try {
+      if (hasTimelineElement) {
+        // Handle timeline element movement
+        const timelineElementData = e.dataTransfer.getData(
+          "application/x-timeline-element"
+        );
+        if (!timelineElementData) return;
+
+        const {
+          elementId,
+          trackId: fromTrackId,
+          clickOffsetTime = 0,
+        } = JSON.parse(timelineElementData);
+
+        // Find the element being moved
+        const sourceTrack = tracks.find(
+          (t: TimelineTrack) => t.id === fromTrackId
+        );
+        const movingElement = sourceTrack?.elements.find(
+          (c: TimelineElementType) => c.id === elementId
+        );
+
+        if (!movingElement) {
+          toast.error("Element not found");
+          return;
+        }
+
+        // Check for overlaps with existing elements (excluding the moving element itself)
+        const movingElementDuration =
+          movingElement.duration -
+          movingElement.trimStart -
+          movingElement.trimEnd;
+
+        // Adjust position based on where user clicked on the element
+        const adjustedStartTime = newStartTime - clickOffsetTime;
+        const snappedStartTime = getDropSnappedTime(
+          adjustedStartTime,
+          movingElementDuration,
+          elementId
+        );
+        const finalStartTime = Math.max(0, snappedStartTime);
+        const movingElementEnd = finalStartTime + movingElementDuration;
+
+        const hasOverlap = track.elements.some((existingElement) => {
+          // Skip the element being moved if it's on the same track
+          if (fromTrackId === track.id && existingElement.id === elementId)
+            return false;
+
+          const existingStart = existingElement.startTime;
+          const existingEnd =
+            existingElement.startTime +
+            (existingElement.duration -
+              existingElement.trimStart -
+              existingElement.trimEnd);
+
+          // Check if elements overlap
+          return (
+            finalStartTime < existingEnd && movingElementEnd > existingStart
+          );
+        });
+
+        if (hasOverlap) {
+          toast.error(
+            "Cannot move element here - it would overlap with existing elements"
+          );
+          return;
+        }
+
+        if (fromTrackId === track.id) {
+          // Moving within same track
+          updateElementStartTime(track.id, elementId, finalStartTime);
+        } else {
+          // Moving to different track
+          moveElementToTrack(fromTrackId, track.id, elementId);
+          requestAnimationFrame(() => {
+            updateElementStartTime(track.id, elementId, finalStartTime);
+          });
+        }
+      } else if (hasMediaItem) {
+        // Handle media item drop
+        const mediaItemData = e.dataTransfer.getData(
+          "application/x-media-item"
+        );
+        if (!mediaItemData) return;
+
+        const dragData: DragData = JSON.parse(mediaItemData);
+
+        if (dragData.type === "text") {
+          let targetTrackId = track.id;
+          let targetTrack = track;
+
+          // Handle position-aware track creation for text
+          if (track.type !== "text" || dropPosition !== "on") {
+            // Text tracks should go above the main track
+            const mainTrack = getMainTrack(tracks);
+            let insertIndex: number;
+
+            if (dropPosition === "above") {
+              insertIndex = currentTrackIndex;
+            } else if (dropPosition === "below") {
+              insertIndex = currentTrackIndex + 1;
+            } else {
+              // dropPosition === "on" but track is not text type
+              // Insert above main track if main track exists, otherwise at top
+              if (mainTrack) {
+                const mainTrackIndex = tracks.findIndex(
+                  (t) => t.id === mainTrack.id
+                );
+                insertIndex = mainTrackIndex;
+              } else {
+                insertIndex = 0; // Top of timeline
+              }
+            }
+
+            targetTrackId = insertTrackAt("text", insertIndex);
+            // Get the updated tracks array after creating the new track
+            const updatedTracks = useTimelineStore.getState().tracks;
+            const newTargetTrack = updatedTracks.find(
+              (t) => t.id === targetTrackId
+            );
+            if (!newTargetTrack) return;
+            targetTrack = newTargetTrack;
+          }
+
+          // Check for overlaps with existing elements in target track
+          const newElementDuration = 5; // Default text duration
+          const textSnappedTime = getDropSnappedTime(
+            newStartTime,
+            newElementDuration
+          );
+          const newElementEnd = textSnappedTime + newElementDuration;
+
+          const hasOverlap = targetTrack.elements.some((existingElement) => {
+            const existingStart = existingElement.startTime;
+            const existingEnd =
+              existingElement.startTime +
+              (existingElement.duration -
+                existingElement.trimStart -
+                existingElement.trimEnd);
+
+            // Check if elements overlap
+            return (
+              textSnappedTime < existingEnd && newElementEnd > existingStart
+            );
+          });
+
+          if (hasOverlap) {
+            toast.error(
+              "Cannot place element here - it would overlap with existing elements"
+            );
+            return;
+          }
+
+          addElementToTrack(targetTrackId, {
+            type: "text",
+            name: dragData.name || "Text",
+            content: dragData.content || "Default Text",
+            duration: TIMELINE_CONSTANTS.DEFAULT_TEXT_DURATION,
+            startTime: textSnappedTime,
+            trimStart: 0,
+            trimEnd: 0,
+            fontSize: 48,
+            fontFamily: "Arial",
+            color: "#ffffff",
+            backgroundColor: "transparent",
+            textAlign: "center",
+            fontWeight: "normal",
+            fontStyle: "normal",
+            textDecoration: "none",
+            x: 0,
+            y: 0,
+            rotation: 0,
+            opacity: 1,
+          });
+        } else {
+          // Handle media items
+          const mediaItem = mediaItems.find((item) => item.id === dragData.id);
+
+          if (!mediaItem) {
+            toast.error("Media item not found");
+            return;
+          }
+
+          let targetTrackId = track.id;
+
+          // Check if track type is compatible
+          const isVideoOrImage =
+            dragData.type === "video" || dragData.type === "image";
+          const isAudio = dragData.type === "audio";
+          const isCompatible = isVideoOrImage
+            ? canElementGoOnTrack("media", track.type)
+            : isAudio
+              ? canElementGoOnTrack("media", track.type)
+              : false;
+
+          let targetTrack = tracks.find((t) => t.id === targetTrackId);
+
+          // Handle position-aware track creation for media elements
+          if (!isCompatible || dropPosition !== "on") {
+            if (isVideoOrImage) {
+              // For video/image, check if we need a main track or additional media track
+              const mainTrack = getMainTrack(tracks);
+
+              if (!mainTrack) {
+                // No main track exists, create it
+                targetTrackId = addTrack("media");
+                const updatedTracks = useTimelineStore.getState().tracks;
+                const newTargetTrack = updatedTracks.find(
+                  (t) => t.id === targetTrackId
+                );
+                if (!newTargetTrack) return;
+                targetTrack = newTargetTrack;
+              } else if (
+                mainTrack.elements.length === 0 &&
+                dropPosition === "on"
+              ) {
+                // Main track exists and is empty, use it
+                targetTrackId = mainTrack.id;
+                targetTrack = mainTrack;
+              } else {
+                // Create new media track
+                let insertIndex: number;
+
+                if (dropPosition === "above") {
+                  insertIndex = currentTrackIndex;
+                } else if (dropPosition === "below") {
+                  insertIndex = currentTrackIndex + 1;
+                } else {
+                  // Insert above main track
+                  const mainTrackIndex = tracks.findIndex(
+                    (t) => t.id === mainTrack.id
+                  );
+                  insertIndex = mainTrackIndex;
+                }
+
+                targetTrackId = insertTrackAt("media", insertIndex);
+                const updatedTracks = useTimelineStore.getState().tracks;
+                const newTargetTrack = updatedTracks.find(
+                  (t) => t.id === targetTrackId
+                );
+                if (!newTargetTrack) return;
+                targetTrack = newTargetTrack;
+              }
+            } else if (isAudio) {
+              // Audio tracks go at the bottom
+              const mainTrack = getMainTrack(tracks);
+              let insertIndex: number;
+
+              if (dropPosition === "above") {
+                insertIndex = currentTrackIndex;
+              } else if (dropPosition === "below") {
+                insertIndex = currentTrackIndex + 1;
+              } else {
+                // Insert after main track (bottom area)
+                if (mainTrack) {
+                  const mainTrackIndex = tracks.findIndex(
+                    (t) => t.id === mainTrack.id
+                  );
+                  insertIndex = mainTrackIndex + 1;
+                } else {
+                  insertIndex = tracks.length; // Bottom of timeline
+                }
+              }
+
+              targetTrackId = insertTrackAt("audio", insertIndex);
+              const updatedTracks = useTimelineStore.getState().tracks;
+              const newTargetTrack = updatedTracks.find(
+                (t) => t.id === targetTrackId
+              );
+              if (!newTargetTrack) return;
+              targetTrack = newTargetTrack;
+            }
+          }
+
+          if (!targetTrack) return;
+
+          // Check for overlaps with existing elements in target track
+          const newElementDuration = mediaItem.duration || 5;
+          const mediaSnappedTime = getDropSnappedTime(
+            newStartTime,
+            newElementDuration
+          );
+          const newElementEnd = mediaSnappedTime + newElementDuration;
+
+          const hasOverlap = targetTrack.elements.some((existingElement) => {
+            const existingStart = existingElement.startTime;
+            const existingEnd =
+              existingElement.startTime +
+              (existingElement.duration -
+                existingElement.trimStart -
+                existingElement.trimEnd);
+
+            // Check if elements overlap
+            return (
+              mediaSnappedTime < existingEnd && newElementEnd > existingStart
+            );
+          });
+
+          if (hasOverlap) {
+            toast.error(
+              "Cannot place element here - it would overlap with existing elements"
+            );
+            return;
+          }
+
+          addElementToTrack(targetTrackId, {
+            type: "media",
+            mediaId: mediaItem.id,
+            name: mediaItem.name,
+            duration: mediaItem.duration || 5,
+            startTime: mediaSnappedTime,
+            trimStart: 0,
+            trimEnd: 0,
+          });
+        }
+      }
+    } catch (error) {
+      console.error("Error handling drop:", error);
+      toast.error("Failed to add media to track");
+    }
+  };
+
+  return (
+    <div
+      className="w-full h-full hover:bg-muted/20"
+      onClick={(e) => {
+        // If clicking empty area (not on an element), deselect all elements
+        if (!(e.target as HTMLElement).closest(".timeline-element")) {
+          clearSelectedElements();
+        }
+      }}
+      onDragOver={handleTrackDragOver}
+      onDragEnter={handleTrackDragEnter}
+      onDragLeave={handleTrackDragLeave}
+      onDrop={handleTrackDrop}
+    >
+      <div
+        ref={timelineRef}
+        className="h-full relative track-elements-container min-w-full"
+      >
+        {track.elements.length === 0 ? (
+          <div
+            className={`h-full w-full border-inset border-b border-dashed flex items-center justify-center text-xs text-muted-foreground transition-colors ${
+              isDropping
+                ? wouldOverlap
+                  ? "rounded-sm border-red-500 bg-red-500/10 text-red-600"
+                  : "rounded-sm border-blue-500 bg-blue-500/10 text-blue-600"
+                : "border-background"
+            }`}
+          >
+            {isDropping
+              ? wouldOverlap
+                ? "Cannot drop - would overlap"
+                : "Drop element here"
+              : ""}
+          </div>
+        ) : (
+          <div
+            className={`h-full w-full border-b border-dashed border-background flex items-center justify-center text-xs text-muted-foreground transition-colors`}
+          >
+            {track.elements.map((element) => {
+              const isSelected = selectedElements.some(
+                (c) => c.trackId === track.id && c.elementId === element.id
+              );
+
+              const handleElementSplit = () => {
+                const { currentTime } = usePlaybackStore();
+                const { splitElement } = useTimelineStore();
+                const splitTime = currentTime;
+                const effectiveStart = element.startTime;
+                const effectiveEnd =
+                  element.startTime +
+                  (element.duration - element.trimStart - element.trimEnd);
+
+                if (splitTime > effectiveStart && splitTime < effectiveEnd) {
+                  const secondElementId = splitElement(
+                    track.id,
+                    element.id,
+                    splitTime
+                  );
+                  if (!secondElementId) {
+                    toast.error("Failed to split element");
+                  }
+                } else {
+                  toast.error("Playhead must be within element to split");
+                }
+              };
+
+              const handleElementDuplicate = () => {
+                const { addElementToTrack } = useTimelineStore.getState();
+                const { id, ...elementWithoutId } = element;
+                addElementToTrack(track.id, {
+                  ...elementWithoutId,
+                  name: element.name + " (copy)",
+                  startTime:
+                    element.startTime +
+                    (element.duration - element.trimStart - element.trimEnd) +
+                    0.1,
+                });
+              };
+
+              const handleElementDelete = () => {
+                const { removeElementFromTrack } = useTimelineStore.getState();
+                removeElementFromTrack(track.id, element.id);
+              };
+
+              return (
+                <TimelineElement
+                  key={element.id}
+                  element={element}
+                  track={track}
+                  zoomLevel={zoomLevel}
+                  isSelected={isSelected}
+                  onElementMouseDown={handleElementMouseDown}
+                  onElementClick={handleElementClick}
+                />
+              );
+            })}
+          </div>
+        )}
+      </div>
+    </div>
+  );
+}