| 1 | "use client"; |
| 2 | |
| 3 | import { |
| 4 | KeyboardSensor, |
| 5 | PointerSensor, |
| 6 | useSensor, |
| 7 | useSensors, |
| 8 | type DragEndEvent, |
| 9 | } from "@dnd-kit/core"; |
| 10 | import { arrayMove, sortableKeyboardCoordinates } from "@dnd-kit/sortable"; |
| 11 | import { useCallback, useMemo } from "react"; |
| 12 | |
| 13 | import { type PlateSlide } from "@/components/notebook/presentation/utils/parser"; |
| 14 | import { usePresentationState } from "@/states/presentation-state"; |
| 15 | |
| 16 | interface SlideWithId extends PlateSlide { |
| 17 | id: string; |
| 18 | } |
| 19 | |
| 20 | export function usePresentationSlides() { |
| 21 | // Subscribe to slide IDs only for rendering - prevents re-render when content changes |
| 22 | // shallow ensures array comparison is shallow (same values = no re-render) |
| 23 | const slideIds = usePresentationState((s) => |
| 24 | s.slides.map((slide) => slide.id), |
| 25 | ); |
| 26 | // Keep full slides reference for drag operations only |
| 27 | const slides = usePresentationState((s) => s.slides); |
| 28 | const setSlides = usePresentationState((s) => s.setSlides); |
| 29 | const setCurrentSlideId = usePresentationState((s) => s.setCurrentSlideId); |
| 30 | const isPresenting = usePresentationState((s) => s.isPresenting); |
| 31 | const setIsReorderingSlides = usePresentationState( |
| 32 | (s) => s.setIsReorderingSlides, |
| 33 | ); |
| 34 | |
| 35 | // Configure DnD sensors |
| 36 | const sensors = useSensors( |
| 37 | useSensor(PointerSensor, { |
| 38 | activationConstraint: { |
| 39 | distance: 8, // 8px |
| 40 | }, |
| 41 | }), |
| 42 | useSensor(KeyboardSensor, { |
| 43 | coordinateGetter: sortableKeyboardCoordinates, |
| 44 | }), |
| 45 | ); |
| 46 | |
| 47 | // Memoize slide IDs for stable reference |
| 48 | const items = useMemo(() => slideIds, [slideIds]); |
| 49 | |
| 50 | // Handle drag end - needs full slides for reordering |
| 51 | const handleDragEnd = useCallback( |
| 52 | (event: DragEndEvent) => { |
| 53 | if (isPresenting) return; // Prevent drag when presenting |
| 54 | |
| 55 | const { active, over } = event; |
| 56 | |
| 57 | if (over && active.id !== over.id) { |
| 58 | const oldIndex = slides.findIndex( |
| 59 | (item: SlideWithId) => item.id === active.id, |
| 60 | ); |
| 61 | const newIndex = slides.findIndex( |
| 62 | (item: SlideWithId) => item.id === over.id, |
| 63 | ); |
| 64 | const newArray = arrayMove(slides, oldIndex, newIndex); |
| 65 | setSlides([...newArray]); |
| 66 | // Update current slide to the dragged slide's ID (not new position index) |
| 67 | setCurrentSlideId(active.id as string); |
| 68 | } |
| 69 | // Clear reordering flag at end |
| 70 | setIsReorderingSlides(false); |
| 71 | }, |
| 72 | [slides, isPresenting, setSlides, setCurrentSlideId, setIsReorderingSlides], |
| 73 | ); |
| 74 | |
| 75 | // Expose a start handler to set reordering flag (to be wired in DndContext) |
| 76 | const handleDragStart = useCallback(() => { |
| 77 | if (isPresenting) return; |
| 78 | setIsReorderingSlides(true); |
| 79 | }, [isPresenting, setIsReorderingSlides]); |
| 80 | |
| 81 | // Scroll to a slide by index |
| 82 | const scrollToSlide = useCallback((id: string) => { |
| 83 | // Target the slide wrapper instead of slide container |
| 84 | const slideElement = document.querySelector(`.slide-wrapper-${id}`); |
| 85 | |
| 86 | if (slideElement) { |
| 87 | // Find the scrollable container |
| 88 | const scrollContainer = document.querySelector(".presentation-slides"); |
| 89 | |
| 90 | if (scrollContainer) { |
| 91 | // Calculate the scroll position |
| 92 | scrollContainer.scrollTo({ |
| 93 | top: (slideElement as HTMLElement).offsetTop - 30, // Add a small offset for better visibility |
| 94 | behavior: "smooth", |
| 95 | }); |
| 96 | } |
| 97 | } |
| 98 | }, []); |
| 99 | |
| 100 | return { |
| 101 | items, |
| 102 | slideIds, |
| 103 | slides, // Still exposed for components that need full slide data |
| 104 | sensors, |
| 105 | isPresenting, |
| 106 | handleDragStart, |
| 107 | handleDragEnd, |
| 108 | scrollToSlide, |
| 109 | }; |
| 110 | } |
| 111 |