Kanban

/**
 * @see https://github.com/radix-ui/primitives/blob/main/packages/react/compose-refs/src/compose-refs.tsx
 */
 
import * as React from "react";
 
type PossibleRef<T> = React.Ref<T> | undefined;
 
/**
 * Set a given ref to a given value
 * This utility takes care of different types of refs: callback refs and RefObject(s)
 */
function setRef<T>(ref: PossibleRef<T>, value: T) {
  if (typeof ref === "function") {
    return ref(value);
  }
 
  if (ref !== null && ref !== undefined) {
    ref.current = value;
  }
}
 
/**
 * A utility to compose multiple refs together
 * Accepts callback refs and RefObject(s)
 */
function composeRefs<T>(...refs: PossibleRef<T>[]): React.RefCallback<T> {
  return (node) => {
    let hasCleanup = false;
    const cleanups = refs.map((ref) => {
      const cleanup = setRef(ref, node);
      if (!hasCleanup && typeof cleanup === "function") {
        hasCleanup = true;
      }
      return cleanup;
    });
 
    // React <19 will log an error to the console if a callback ref returns a
    // value. We don't use ref cleanups internally so this will only happen if a
    // user's ref callback returns a value, which we only expect if they are
    // using the cleanup functionality added in React 19.
    if (hasCleanup) {
      return () => {
        for (let i = 0; i < cleanups.length; i++) {
          const cleanup = cleanups[i];
          if (typeof cleanup === "function") {
            cleanup();
          } else {
            setRef(refs[i], null);
          }
        }
      };
    }
  };
}
 
/**
 * A custom hook that composes multiple refs
 * Accepts callback refs and RefObject(s)
 */
function useComposedRefs<T>(...refs: PossibleRef<T>[]): React.RefCallback<T> {
  // biome-ignore lint/correctness/useExhaustiveDependencies: we want to memoize by all values
  return React.useCallback(composeRefs(...refs), refs);
}
 
export { composeRefs, useComposedRefs };

"use client";
 
import {
  type Announcements,
  type CollisionDetection,
  closestCenter,
  closestCorners,
  DndContext,
  type DndContextProps,
  type DragCancelEvent,
  type DragEndEvent,
  type DraggableAttributes,
  type DraggableSyntheticListeners,
  type DragOverEvent,
  DragOverlay,
  type DragStartEvent,
  type DropAnimation,
  type DroppableContainer,
  defaultDropAnimationSideEffects,
  getFirstCollision,
  KeyboardCode,
  type KeyboardCoordinateGetter,
  KeyboardSensor,
  MeasuringStrategy,
  MouseSensor,
  pointerWithin,
  rectIntersection,
  TouchSensor,
  type UniqueIdentifier,
  useSensor,
  useSensors,
} from "@dnd-kit/core";
import {
  type AnimateLayoutChanges,
  arrayMove,
  defaultAnimateLayoutChanges,
  horizontalListSortingStrategy,
  SortableContext,
  type SortableContextProps,
  useSortable,
  verticalListSortingStrategy,
} from "@dnd-kit/sortable";
import { CSS } from "@dnd-kit/utilities";
import { Slot } from "@radix-ui/react-slot";
import * as React from "react";
import * as ReactDOM from "react-dom";
 
import { useComposedRefs } from "@/lib/compose-refs";
import { cn } from "@/lib/utils";
 
const directions: string[] = [
  KeyboardCode.Down,
  KeyboardCode.Right,
  KeyboardCode.Up,
  KeyboardCode.Left,
];
 
const coordinateGetter: KeyboardCoordinateGetter = (event, { context }) => {
  const { active, droppableRects, droppableContainers, collisionRect } =
    context;
 
  if (directions.includes(event.code)) {
    event.preventDefault();
 
    if (!active || !collisionRect) return;
 
    const filteredContainers: DroppableContainer[] = [];
 
    for (const entry of droppableContainers.getEnabled()) {
      if (!entry || entry?.disabled) return;
 
      const rect = droppableRects.get(entry.id);
 
      if (!rect) return;
 
      const data = entry.data.current;
 
      if (data) {
        const { type, children } = data;
 
        if (type === "container" && children?.length > 0) {
          if (active.data.current?.type !== "container") {
            return;
          }
        }
      }
 
      switch (event.code) {
        case KeyboardCode.Down:
          if (collisionRect.top < rect.top) {
            filteredContainers.push(entry);
          }
          break;
        case KeyboardCode.Up:
          if (collisionRect.top > rect.top) {
            filteredContainers.push(entry);
          }
          break;
        case KeyboardCode.Left:
          if (collisionRect.left >= rect.left + rect.width) {
            filteredContainers.push(entry);
          }
          break;
        case KeyboardCode.Right:
          if (collisionRect.left + collisionRect.width <= rect.left) {
            filteredContainers.push(entry);
          }
          break;
      }
    }
 
    const collisions = closestCorners({
      active,
      collisionRect: collisionRect,
      droppableRects,
      droppableContainers: filteredContainers,
      pointerCoordinates: null,
    });
    const closestId = getFirstCollision(collisions, "id");
 
    if (closestId != null) {
      const newDroppable = droppableContainers.get(closestId);
      const newNode = newDroppable?.node.current;
      const newRect = newDroppable?.rect.current;
 
      if (newNode && newRect) {
        if (newDroppable.id === "placeholder") {
          return {
            x: newRect.left + (newRect.width - collisionRect.width) / 2,
            y: newRect.top + (newRect.height - collisionRect.height) / 2,
          };
        }
 
        if (newDroppable.data.current?.type === "container") {
          return {
            x: newRect.left + 20,
            y: newRect.top + 74,
          };
        }
 
        return {
          x: newRect.left,
          y: newRect.top,
        };
      }
    }
  }
 
  return undefined;
};
 
const ROOT_NAME = "Kanban";
const BOARD_NAME = "KanbanBoard";
const COLUMN_NAME = "KanbanColumn";
const COLUMN_HANDLE_NAME = "KanbanColumnHandle";
const ITEM_NAME = "KanbanItem";
const ITEM_HANDLE_NAME = "KanbanItemHandle";
const OVERLAY_NAME = "KanbanOverlay";
 
interface KanbanContextValue<T> {
  id: string;
  items: Record<UniqueIdentifier, T[]>;
  modifiers: DndContextProps["modifiers"];
  strategy: SortableContextProps["strategy"];
  orientation: "horizontal" | "vertical";
  activeId: UniqueIdentifier | null;
  setActiveId: (id: UniqueIdentifier | null) => void;
  getItemValue: (item: T) => UniqueIdentifier;
  flatCursor: boolean;
}
 
const KanbanContext = React.createContext<KanbanContextValue<unknown> | null>(
  null,
);
 
function useKanbanContext(consumerName: string) {
  const context = React.useContext(KanbanContext);
  if (!context) {
    throw new Error(`\`${consumerName}\` must be used within \`${ROOT_NAME}\``);
  }
  return context;
}
 
interface GetItemValue<T> {
  /**
   * Callback that returns a unique identifier for each kanban item. Required for array of objects.
   * @example getItemValue={(item) => item.id}
   */
  getItemValue: (item: T) => UniqueIdentifier;
}
 
type KanbanRootProps<T> = Omit<DndContextProps, "collisionDetection"> &
  (T extends object ? GetItemValue<T> : Partial<GetItemValue<T>>) & {
    value: Record<UniqueIdentifier, T[]>;
    onValueChange?: (columns: Record<UniqueIdentifier, T[]>) => void;
    onMove?: (
      event: DragEndEvent & { activeIndex: number; overIndex: number },
    ) => void;
    strategy?: SortableContextProps["strategy"];
    orientation?: "horizontal" | "vertical";
    flatCursor?: boolean;
  };
 
function KanbanRoot<T>(props: KanbanRootProps<T>) {
  const {
    value,
    onValueChange,
    modifiers,
    strategy = verticalListSortingStrategy,
    orientation = "horizontal",
    onMove,
    getItemValue: getItemValueProp,
    accessibility,
    flatCursor = false,
    ...kanbanProps
  } = props;
 
  const id = React.useId();
  const [activeId, setActiveId] = React.useState<UniqueIdentifier | null>(null);
  const lastOverIdRef = React.useRef<UniqueIdentifier | null>(null);
  const hasMovedRef = React.useRef(false);
  const sensors = useSensors(
    useSensor(MouseSensor),
    useSensor(TouchSensor),
    useSensor(KeyboardSensor, {
      coordinateGetter,
    }),
  );
 
  const getItemValue = React.useCallback(
    (item: T): UniqueIdentifier => {
      if (typeof item === "object" && !getItemValueProp) {
        throw new Error("getItemValue is required when using array of objects");
      }
      return getItemValueProp
        ? getItemValueProp(item)
        : (item as UniqueIdentifier);
    },
    [getItemValueProp],
  );
 
  const getColumn = React.useCallback(
    (id: UniqueIdentifier) => {
      if (id in value) return id;
 
      for (const [columnId, items] of Object.entries(value)) {
        if (items.some((item) => getItemValue(item) === id)) {
          return columnId;
        }
      }
 
      return null;
    },
    [value, getItemValue],
  );
 
  const collisionDetection: CollisionDetection = React.useCallback(
    (args) => {
      if (activeId && activeId in value) {
        return closestCenter({
          ...args,
          droppableContainers: args.droppableContainers.filter(
            (container) => container.id in value,
          ),
        });
      }
 
      const pointerIntersections = pointerWithin(args);
      const intersections =
        pointerIntersections.length > 0
          ? pointerIntersections
          : rectIntersection(args);
      let overId = getFirstCollision(intersections, "id");
 
      if (!overId) {
        if (hasMovedRef.current) {
          lastOverIdRef.current = activeId;
        }
        return lastOverIdRef.current ? [{ id: lastOverIdRef.current }] : [];
      }
 
      if (overId in value) {
        const containerItems = value[overId];
        if (containerItems && containerItems.length > 0) {
          const closestItem = closestCenter({
            ...args,
            droppableContainers: args.droppableContainers.filter(
              (container) =>
                container.id !== overId &&
                containerItems.some(
                  (item) => getItemValue(item) === container.id,
                ),
            ),
          });
 
          if (closestItem.length > 0) {
            overId = closestItem[0]?.id ?? overId;
          }
        }
      }
 
      lastOverIdRef.current = overId;
      return [{ id: overId }];
    },
    [activeId, value, getItemValue],
  );
 
  const onDragStart = React.useCallback(
    (event: DragStartEvent) => {
      kanbanProps.onDragStart?.(event);
 
      if (event.activatorEvent.defaultPrevented) return;
      setActiveId(event.active.id);
    },
    [kanbanProps.onDragStart],
  );
 
  const onDragOver = React.useCallback(
    (event: DragOverEvent) => {
      kanbanProps.onDragOver?.(event);
 
      if (event.activatorEvent.defaultPrevented) return;
 
      const { active, over } = event;
      if (!over) return;
 
      const activeColumn = getColumn(active.id);
      const overColumn = getColumn(over.id);
 
      if (!activeColumn || !overColumn) return;
 
      if (activeColumn === overColumn) {
        const items = value[activeColumn];
        if (!items) return;
 
        const activeIndex = items.findIndex(
          (item) => getItemValue(item) === active.id,
        );
        const overIndex = items.findIndex(
          (item) => getItemValue(item) === over.id,
        );
 
        if (activeIndex !== overIndex) {
          const newColumns = { ...value };
          newColumns[activeColumn] = arrayMove(items, activeIndex, overIndex);
          onValueChange?.(newColumns);
        }
      } else {
        const activeItems = value[activeColumn];
        const overItems = value[overColumn];
 
        if (!activeItems || !overItems) return;
 
        const activeIndex = activeItems.findIndex(
          (item) => getItemValue(item) === active.id,
        );
 
        if (activeIndex === -1) return;
 
        const activeItem = activeItems[activeIndex];
        if (!activeItem) return;
 
        const updatedItems = {
          ...value,
          [activeColumn]: activeItems.filter(
            (item) => getItemValue(item) !== active.id,
          ),
          [overColumn]: [...overItems, activeItem],
        };
 
        onValueChange?.(updatedItems);
        hasMovedRef.current = true;
      }
    },
    [value, getColumn, getItemValue, onValueChange, kanbanProps.onDragOver],
  );
 
  const onDragEnd = React.useCallback(
    (event: DragEndEvent) => {
      kanbanProps.onDragEnd?.(event);
 
      if (event.activatorEvent.defaultPrevented) return;
 
      const { active, over } = event;
 
      if (!over) {
        setActiveId(null);
        return;
      }
 
      if (active.id in value && over.id in value) {
        const activeIndex = Object.keys(value).indexOf(active.id as string);
        const overIndex = Object.keys(value).indexOf(over.id as string);
 
        if (activeIndex !== overIndex) {
          const orderedColumns = Object.keys(value);
          const newOrder = arrayMove(orderedColumns, activeIndex, overIndex);
 
          const newColumns: Record<UniqueIdentifier, T[]> = {};
          for (const key of newOrder) {
            const items = value[key];
            if (items) {
              newColumns[key] = items;
            }
          }
 
          if (onMove) {
            onMove({ ...event, activeIndex, overIndex });
          } else {
            onValueChange?.(newColumns);
          }
        }
      } else {
        const activeColumn = getColumn(active.id);
        const overColumn = getColumn(over.id);
 
        if (!activeColumn || !overColumn) {
          setActiveId(null);
          return;
        }
 
        if (activeColumn === overColumn) {
          const items = value[activeColumn];
          if (!items) {
            setActiveId(null);
            return;
          }
 
          const activeIndex = items.findIndex(
            (item) => getItemValue(item) === active.id,
          );
          const overIndex = items.findIndex(
            (item) => getItemValue(item) === over.id,
          );
 
          if (activeIndex !== overIndex) {
            const newColumns = { ...value };
            newColumns[activeColumn] = arrayMove(items, activeIndex, overIndex);
            if (onMove) {
              onMove({
                ...event,
                activeIndex,
                overIndex,
              });
            } else {
              onValueChange?.(newColumns);
            }
          }
        }
      }
 
      setActiveId(null);
      hasMovedRef.current = false;
    },
    [
      value,
      getColumn,
      getItemValue,
      onValueChange,
      onMove,
      kanbanProps.onDragEnd,
    ],
  );
 
  const onDragCancel = React.useCallback(
    (event: DragCancelEvent) => {
      kanbanProps.onDragCancel?.(event);
 
      if (event.activatorEvent.defaultPrevented) return;
 
      setActiveId(null);
      hasMovedRef.current = false;
    },
    [kanbanProps.onDragCancel],
  );
 
  const announcements: Announcements = React.useMemo(
    () => ({
      onDragStart({ active }) {
        const isColumn = active.id in value;
        const itemType = isColumn ? "column" : "item";
        const position = isColumn
          ? Object.keys(value).indexOf(active.id as string) + 1
          : (() => {
              const column = getColumn(active.id);
              if (!column || !value[column]) return 1;
              return (
                value[column].findIndex(
                  (item) => getItemValue(item) === active.id,
                ) + 1
              );
            })();
        const total = isColumn
          ? Object.keys(value).length
          : (() => {
              const column = getColumn(active.id);
              return column ? (value[column]?.length ?? 0) : 0;
            })();
 
        return `Picked up ${itemType} at position ${position} of ${total}`;
      },
      onDragOver({ active, over }) {
        if (!over) return;
 
        const isColumn = active.id in value;
        const itemType = isColumn ? "column" : "item";
        const position = isColumn
          ? Object.keys(value).indexOf(over.id as string) + 1
          : (() => {
              const column = getColumn(over.id);
              if (!column || !value[column]) return 1;
              return (
                value[column].findIndex(
                  (item) => getItemValue(item) === over.id,
                ) + 1
              );
            })();
        const total = isColumn
          ? Object.keys(value).length
          : (() => {
              const column = getColumn(over.id);
              return column ? (value[column]?.length ?? 0) : 0;
            })();
 
        const overColumn = getColumn(over.id);
        const activeColumn = getColumn(active.id);
 
        if (isColumn) {
          return `${itemType} is now at position ${position} of ${total}`;
        }
 
        if (activeColumn !== overColumn) {
          return `${itemType} is now at position ${position} of ${total} in ${overColumn}`;
        }
 
        return `${itemType} is now at position ${position} of ${total}`;
      },
      onDragEnd({ active, over }) {
        if (!over) return;
 
        const isColumn = active.id in value;
        const itemType = isColumn ? "column" : "item";
        const position = isColumn
          ? Object.keys(value).indexOf(over.id as string) + 1
          : (() => {
              const column = getColumn(over.id);
              if (!column || !value[column]) return 1;
              return (
                value[column].findIndex(
                  (item) => getItemValue(item) === over.id,
                ) + 1
              );
            })();
        const total = isColumn
          ? Object.keys(value).length
          : (() => {
              const column = getColumn(over.id);
              return column ? (value[column]?.length ?? 0) : 0;
            })();
 
        const overColumn = getColumn(over.id);
        const activeColumn = getColumn(active.id);
 
        if (isColumn) {
          return `${itemType} was dropped at position ${position} of ${total}`;
        }
 
        if (activeColumn !== overColumn) {
          return `${itemType} was dropped at position ${position} of ${total} in ${overColumn}`;
        }
 
        return `${itemType} was dropped at position ${position} of ${total}`;
      },
      onDragCancel({ active }) {
        const isColumn = active.id in value;
        const itemType = isColumn ? "column" : "item";
        return `Dragging was cancelled. ${itemType} was dropped.`;
      },
    }),
    [value, getColumn, getItemValue],
  );
 
  const contextValue = React.useMemo<KanbanContextValue<T>>(
    () => ({
      id,
      items: value,
      modifiers,
      strategy,
      orientation,
      activeId,
      setActiveId,
      getItemValue,
      flatCursor,
    }),
    [
      id,
      value,
      activeId,
      modifiers,
      strategy,
      orientation,
      getItemValue,
      flatCursor,
    ],
  );
 
  return (
    <KanbanContext.Provider value={contextValue as KanbanContextValue<unknown>}>
      <DndContext
        collisionDetection={collisionDetection}
        modifiers={modifiers}
        sensors={sensors}
        {...kanbanProps}
        id={id}
        measuring={{
          droppable: {
            strategy: MeasuringStrategy.Always,
          },
        }}
        onDragStart={onDragStart}
        onDragOver={onDragOver}
        onDragEnd={onDragEnd}
        onDragCancel={onDragCancel}
        accessibility={{
          announcements,
          screenReaderInstructions: {
            draggable: `
            To pick up a kanban item or column, press space or enter.
            While dragging, use the arrow keys to move the item.
            Press space or enter again to drop the item in its new position, or press escape to cancel.
          `,
          },
          ...accessibility,
        }}
      />
    </KanbanContext.Provider>
  );
}
 
const KanbanBoardContext = React.createContext<boolean>(false);
 
interface KanbanBoardProps extends React.ComponentProps<"div"> {
  children: React.ReactNode;
  asChild?: boolean;
}
 
function KanbanBoard(props: KanbanBoardProps) {
  const { asChild, className, ref, ...boardProps } = props;
 
  const context = useKanbanContext(BOARD_NAME);
 
  const columns = React.useMemo(() => {
    return Object.keys(context.items);
  }, [context.items]);
 
  const BoardPrimitive = asChild ? Slot : "div";
 
  return (
    <KanbanBoardContext.Provider value={true}>
      <SortableContext
        items={columns}
        strategy={
          context.orientation === "horizontal"
            ? horizontalListSortingStrategy
            : verticalListSortingStrategy
        }
      >
        <BoardPrimitive
          aria-orientation={context.orientation}
          data-orientation={context.orientation}
          data-slot="kanban-board"
          {...boardProps}
          ref={ref}
          className={cn(
            "flex size-full gap-4",
            context.orientation === "horizontal" ? "flex-row" : "flex-col",
            className,
          )}
        />
      </SortableContext>
    </KanbanBoardContext.Provider>
  );
}
 
interface KanbanColumnContextValue {
  id: string;
  attributes: DraggableAttributes;
  listeners: DraggableSyntheticListeners | undefined;
  setActivatorNodeRef: (node: HTMLElement | null) => void;
  isDragging?: boolean;
  disabled?: boolean;
}
 
const KanbanColumnContext =
  React.createContext<KanbanColumnContextValue | null>(null);
 
function useKanbanColumnContext(consumerName: string) {
  const context = React.useContext(KanbanColumnContext);
  if (!context) {
    throw new Error(
      `\`${consumerName}\` must be used within \`${COLUMN_NAME}\``,
    );
  }
  return context;
}
 
const animateLayoutChanges: AnimateLayoutChanges = (args) =>
  defaultAnimateLayoutChanges({ ...args, wasDragging: true });
 
interface KanbanColumnProps extends React.ComponentProps<"div"> {
  value: UniqueIdentifier;
  children: React.ReactNode;
  asChild?: boolean;
  asHandle?: boolean;
  disabled?: boolean;
}
 
function KanbanColumn(props: KanbanColumnProps) {
  const {
    value,
    asChild,
    asHandle,
    disabled,
    className,
    style,
    ref,
    ...columnProps
  } = props;
 
  const id = React.useId();
  const context = useKanbanContext(COLUMN_NAME);
  const inBoard = React.useContext(KanbanBoardContext);
  const inOverlay = React.useContext(KanbanOverlayContext);
 
  if (!inBoard && !inOverlay) {
    throw new Error(
      `\`${COLUMN_NAME}\` must be used within \`${BOARD_NAME}\` or \`${OVERLAY_NAME}\``,
    );
  }
 
  if (value === "") {
    throw new Error(`\`${COLUMN_NAME}\` value cannot be an empty string`);
  }
 
  const {
    attributes,
    listeners,
    setNodeRef,
    setActivatorNodeRef,
    transform,
    transition,
    isDragging,
  } = useSortable({
    id: value,
    disabled,
    animateLayoutChanges,
  });
 
  const composedRef = useComposedRefs(ref, (node) => {
    if (disabled) return;
    setNodeRef(node);
  });
 
  const composedStyle = React.useMemo<React.CSSProperties>(() => {
    return {
      transform: CSS.Transform.toString(transform),
      transition,
      ...style,
    };
  }, [transform, transition, style]);
 
  const items = React.useMemo(() => {
    const items = context.items[value] ?? [];
    return items.map((item) => context.getItemValue(item));
  }, [context.items, value, context.getItemValue]);
 
  const columnContext = React.useMemo<KanbanColumnContextValue>(
    () => ({
      id,
      attributes,
      listeners,
      setActivatorNodeRef,
      isDragging,
      disabled,
    }),
    [id, attributes, listeners, setActivatorNodeRef, isDragging, disabled],
  );
 
  const ColumnPrimitive = asChild ? Slot : "div";
 
  return (
    <KanbanColumnContext.Provider value={columnContext}>
      <SortableContext
        items={items}
        strategy={
          context.orientation === "horizontal"
            ? horizontalListSortingStrategy
            : verticalListSortingStrategy
        }
      >
        <ColumnPrimitive
          id={id}
          data-disabled={disabled}
          data-dragging={isDragging ? "" : undefined}
          data-slot="kanban-column"
          {...columnProps}
          {...(asHandle && !disabled ? attributes : {})}
          {...(asHandle && !disabled ? listeners : {})}
          ref={composedRef}
          style={composedStyle}
          className={cn(
            "flex size-full flex-col gap-2 rounded-lg border bg-zinc-100 p-2.5 aria-disabled:pointer-events-none aria-disabled:opacity-50 dark:bg-zinc-900",
            {
              "touch-none select-none": asHandle,
              "cursor-default": context.flatCursor,
              "data-dragging:cursor-grabbing": !context.flatCursor,
              "cursor-grab": !isDragging && asHandle && !context.flatCursor,
              "opacity-50": isDragging,
              "pointer-events-none opacity-50": disabled,
            },
            className,
          )}
        />
      </SortableContext>
    </KanbanColumnContext.Provider>
  );
}
 
interface KanbanColumnHandleProps extends React.ComponentProps<"button"> {
  asChild?: boolean;
}
 
function KanbanColumnHandle(props: KanbanColumnHandleProps) {
  const { asChild, disabled, className, ref, ...columnHandleProps } = props;
 
  const context = useKanbanContext(COLUMN_NAME);
  const columnContext = useKanbanColumnContext(COLUMN_HANDLE_NAME);
 
  const isDisabled = disabled ?? columnContext.disabled;
 
  const composedRef = useComposedRefs(ref, (node) => {
    if (isDisabled) return;
    columnContext.setActivatorNodeRef(node);
  });
 
  const HandlePrimitive = asChild ? Slot : "button";
 
  return (
    <HandlePrimitive
      type="button"
      aria-controls={columnContext.id}
      data-disabled={isDisabled}
      data-dragging={columnContext.isDragging ? "" : undefined}
      data-slot="kanban-column-handle"
      {...columnHandleProps}
      {...(isDisabled ? {} : columnContext.attributes)}
      {...(isDisabled ? {} : columnContext.listeners)}
      ref={composedRef}
      className={cn(
        "select-none disabled:pointer-events-none disabled:opacity-50",
        context.flatCursor
          ? "cursor-default"
          : "cursor-grab data-dragging:cursor-grabbing",
        className,
      )}
      disabled={isDisabled}
    />
  );
}
 
interface KanbanItemContextValue {
  id: string;
  attributes: DraggableAttributes;
  listeners: DraggableSyntheticListeners | undefined;
  setActivatorNodeRef: (node: HTMLElement | null) => void;
  isDragging?: boolean;
  disabled?: boolean;
}
 
const KanbanItemContext = React.createContext<KanbanItemContextValue | null>(
  null,
);
 
function useKanbanItemContext(consumerName: string) {
  const context = React.useContext(KanbanItemContext);
  if (!context) {
    throw new Error(`\`${consumerName}\` must be used within \`${ITEM_NAME}\``);
  }
  return context;
}
 
interface KanbanItemProps extends React.ComponentProps<"div"> {
  value: UniqueIdentifier;
  asHandle?: boolean;
  asChild?: boolean;
  disabled?: boolean;
}
 
function KanbanItem(props: KanbanItemProps) {
  const {
    value,
    style,
    asHandle,
    asChild,
    disabled,
    className,
    ref,
    ...itemProps
  } = props;
 
  const id = React.useId();
  const context = useKanbanContext(ITEM_NAME);
  const inBoard = React.useContext(KanbanBoardContext);
  const inOverlay = React.useContext(KanbanOverlayContext);
 
  if (!inBoard && !inOverlay) {
    throw new Error(`\`${ITEM_NAME}\` must be used within \`${BOARD_NAME}\``);
  }
 
  const {
    attributes,
    listeners,
    setNodeRef,
    setActivatorNodeRef,
    transform,
    transition,
    isDragging,
  } = useSortable({ id: value, disabled });
 
  if (value === "") {
    throw new Error(`\`${ITEM_NAME}\` value cannot be an empty string`);
  }
 
  const composedRef = useComposedRefs(ref, (node) => {
    if (disabled) return;
    setNodeRef(node);
  });
 
  const composedStyle = React.useMemo<React.CSSProperties>(() => {
    return {
      transform: CSS.Transform.toString(transform),
      transition,
      ...style,
    };
  }, [transform, transition, style]);
 
  const itemContext = React.useMemo<KanbanItemContextValue>(
    () => ({
      id,
      attributes,
      listeners,
      setActivatorNodeRef,
      isDragging,
      disabled,
    }),
    [id, attributes, listeners, setActivatorNodeRef, isDragging, disabled],
  );
 
  const ItemPrimitive = asChild ? Slot : "div";
 
  return (
    <KanbanItemContext.Provider value={itemContext}>
      <ItemPrimitive
        id={id}
        data-disabled={disabled}
        data-dragging={isDragging ? "" : undefined}
        data-slot="kanban-item"
        {...itemProps}
        {...(asHandle && !disabled ? attributes : {})}
        {...(asHandle && !disabled ? listeners : {})}
        ref={composedRef}
        style={composedStyle}
        className={cn(
          "focus-visible:outline-hidden focus-visible:ring-1 focus-visible:ring-ring focus-visible:ring-offset-1",
          {
            "touch-none select-none": asHandle,
            "cursor-default": context.flatCursor,
            "data-dragging:cursor-grabbing": !context.flatCursor,
            "cursor-grab": !isDragging && asHandle && !context.flatCursor,
            "opacity-50": isDragging,
            "pointer-events-none opacity-50": disabled,
          },
          className,
        )}
      />
    </KanbanItemContext.Provider>
  );
}
 
interface KanbanItemHandleProps extends React.ComponentProps<"button"> {
  asChild?: boolean;
}
 
function KanbanItemHandle(props: KanbanItemHandleProps) {
  const { asChild, disabled, className, ref, ...itemHandleProps } = props;
 
  const context = useKanbanContext(ITEM_HANDLE_NAME);
  const itemContext = useKanbanItemContext(ITEM_HANDLE_NAME);
 
  const isDisabled = disabled ?? itemContext.disabled;
 
  const composedRef = useComposedRefs(ref, (node) => {
    if (isDisabled) return;
    itemContext.setActivatorNodeRef(node);
  });
 
  const HandlePrimitive = asChild ? Slot : "button";
 
  return (
    <HandlePrimitive
      type="button"
      aria-controls={itemContext.id}
      data-disabled={isDisabled}
      data-dragging={itemContext.isDragging ? "" : undefined}
      data-slot="kanban-item-handle"
      {...itemHandleProps}
      {...(isDisabled ? {} : itemContext.attributes)}
      {...(isDisabled ? {} : itemContext.listeners)}
      ref={composedRef}
      className={cn(
        "select-none disabled:pointer-events-none disabled:opacity-50",
        context.flatCursor
          ? "cursor-default"
          : "cursor-grab data-dragging:cursor-grabbing",
        className,
      )}
      disabled={isDisabled}
    />
  );
}
 
const KanbanOverlayContext = React.createContext(false);
 
const dropAnimation: DropAnimation = {
  sideEffects: defaultDropAnimationSideEffects({
    styles: {
      active: {
        opacity: "0.4",
      },
    },
  }),
};
 
interface KanbanOverlayProps
  extends Omit<React.ComponentProps<typeof DragOverlay>, "children"> {
  container?: Element | DocumentFragment | null;
  children?:
    | React.ReactNode
    | ((params: {
        value: UniqueIdentifier;
        variant: "column" | "item";
      }) => React.ReactNode);
}
 
function KanbanOverlay(props: KanbanOverlayProps) {
  const { container: containerProp, children, ...overlayProps } = props;
 
  const context = useKanbanContext(OVERLAY_NAME);
 
  const [mounted, setMounted] = React.useState(false);
  React.useLayoutEffect(() => setMounted(true), []);
 
  const container =
    containerProp ?? (mounted ? globalThis.document?.body : null);
 
  if (!container) return null;
 
  const variant =
    context.activeId && context.activeId in context.items ? "column" : "item";
 
  return ReactDOM.createPortal(
    <DragOverlay
      dropAnimation={dropAnimation}
      modifiers={context.modifiers}
      className={cn(!context.flatCursor && "cursor-grabbing")}
      {...overlayProps}
    >
      <KanbanOverlayContext.Provider value={true}>
        {context.activeId && children
          ? typeof children === "function"
            ? children({
                value: context.activeId,
                variant,
              })
            : children
          : null}
      </KanbanOverlayContext.Provider>
    </DragOverlay>,
    container,
  );
}
 
export {
  KanbanRoot as Kanban,
  KanbanBoard,
  KanbanColumn,
  KanbanColumnHandle,
  KanbanItem,
  KanbanItemHandle,
  KanbanOverlay,
  //
  KanbanRoot as Root,
  KanbanBoard as Board,
  KanbanColumn as Column,
  KanbanColumnHandle as ColumnHandle,
  KanbanItem as Item,
  KanbanItemHandle as ItemHandle,
  KanbanOverlay as Overlay,
};