AI Sidebar

"use client";
// beui.dev/components/agents/ai-sidebar

import {
  ArrowDown,
  ArrowUp,
  Bookmark,
  FileText,
  Folder,
  FolderInput,
  FolderOpen,
  type LucideIcon,
  MoreHorizontal,
  Pencil,
  Undo2,
} from "lucide-react";
import { AnimatePresence, motion, useReducedMotion } from "motion/react";
import {
  type DragEvent,
  type KeyboardEvent,
  type ReactNode,
  useCallback,
  useEffect,
  useMemo,
  useRef,
  useState,
} from "react";
import {
  MorphPopover,
  MorphPopoverContent,
  MorphPopoverTrigger,
} from "@/components/motion/popover-morph";
import { EASE_OUT, SPRING_LAYOUT } from "@/lib/ease";
import { useTouchCapable } from "@/lib/hooks/use-touch-capable";
import { cn } from "@/lib/utils";

export type SidebarResourceKind =
  | "folder"
  | "project"
  | "file"
  | "bookmark";

export interface SidebarResource {
  id: string;
  label: string;
  kind: SidebarResourceKind;
  children?: SidebarResource[];
  disabled?: boolean;
}

export type SidebarResourceDropPosition = "before" | "inside" | "after";

export interface SidebarResourceMove {
  itemId: string;
  targetId: string | null;
  position: SidebarResourceDropPosition;
}

/**
 * The moves this row can make right now, the same four the keyboard offers on
 * `Alt+Shift+Arrow`. A pointer drag is the fast path for them; a finger has no
 * drag to give, so the row menu carries them too. Absent keys are moves this
 * row cannot make from where it sits.
 */
export interface SidebarResourceMoveCommands {
  up?: () => void;
  down?: () => void;
  into?: { label: string; run: () => void };
  out?: () => void;
}

export interface SidebarResourceMenuControls {
  close: () => void;
  rename: () => void;
  moves: SidebarResourceMoveCommands;
}

export interface AISidebarProps {
  items?: SidebarResource[];
  defaultItems?: SidebarResource[];
  onItemsChange?: (items: SidebarResource[]) => void;
  /** Reject the promise to roll the optimistic move back. */
  onMove?: (move: SidebarResourceMove) => void | Promise<void>;
  onMoveError?: (error: unknown, move: SidebarResourceMove) => void;
  onRename?: (item: SidebarResource, label: string) => void | Promise<void>;
  activeId?: string | null;
  defaultActiveId?: string | null;
  onActiveChange?: (id: string) => void;
  defaultExpandedIds?: string[];
  renderIcon?: (item: SidebarResource) => ReactNode;
  renderMenu?: (
    item: SidebarResource,
    controls: SidebarResourceMenuControls,
  ) => ReactNode;
  ariaLabel?: string;
  className?: string;
}

interface FlatResource {
  item: SidebarResource;
  depth: number;
  parentId: string | null;
}

interface DropTarget {
  id: string | null;
  position: SidebarResourceDropPosition;
}

const ROW_REVEAL = {
  duration: 0.16,
  ease: EASE_OUT,
} as const;

function canContain(item: SidebarResource) {
  return item.kind === "folder" || item.kind === "project";
}

function flattenResources(
  items: SidebarResource[],
  expanded: Set<string>,
  depth = 0,
  parentId: string | null = null,
): FlatResource[] {
  return items.flatMap((item) => {
    const row = { item, depth, parentId };
    if (!item.children?.length || !expanded.has(item.id)) return [row];
    return [
      row,
      ...flattenResources(item.children, expanded, depth + 1, item.id),
    ];
  });
}

function findResource(
  items: SidebarResource[],
  id: string,
): SidebarResource | undefined {
  for (const item of items) {
    if (item.id === id) return item;
    const child = item.children ? findResource(item.children, id) : undefined;
    if (child) return child;
  }
}

function containsResource(item: SidebarResource, id: string): boolean {
  return (
    item.id === id ||
    item.children?.some((child) => containsResource(child, id)) === true
  );
}

function removeResource(
  items: SidebarResource[],
  id: string,
): { items: SidebarResource[]; removed?: SidebarResource } {
  let removed: SidebarResource | undefined;
  const next: SidebarResource[] = [];

  for (const item of items) {
    if (item.id === id) {
      removed = item;
      continue;
    }

    if (item.children?.length) {
      const childResult = removeResource(item.children, id);
      if (childResult.removed) {
        removed = childResult.removed;
        next.push({ ...item, children: childResult.items });
        continue;
      }
    }

    next.push(item);
  }

  return { items: next, removed };
}

function insertResource(
  items: SidebarResource[],
  resource: SidebarResource,
  targetId: string | null,
  position: SidebarResourceDropPosition,
): SidebarResource[] {
  if (targetId === null) return [...items, resource];

  const next: SidebarResource[] = [];
  for (const item of items) {
    if (item.id === targetId) {
      if (position === "before") next.push(resource, item);
      else if (position === "after") next.push(item, resource);
      else next.push({ ...item, children: [...(item.children ?? []), resource] });
      continue;
    }

    if (item.children?.length) {
      next.push({
        ...item,
        children: insertResource(item.children, resource, targetId, position),
      });
    } else {
      next.push(item);
    }
  }
  return next;
}

function moveResource(
  items: SidebarResource[],
  move: SidebarResourceMove,
): SidebarResource[] | null {
  const source = findResource(items, move.itemId);
  if (!source || source.disabled) return null;
  if (move.targetId && containsResource(source, move.targetId)) return null;

  const target = move.targetId ? findResource(items, move.targetId) : undefined;
  if (
    move.position === "inside" &&
    (!target || target.disabled || !canContain(target))
  )
    return null;

  const removed = removeResource(items, move.itemId);
  if (!removed.removed) return null;
  return insertResource(
    removed.items,
    removed.removed,
    move.targetId,
    move.position,
  );
}

function renameResource(
  items: SidebarResource[],
  id: string,
  label: string,
): SidebarResource[] {
  return items.map((item) => ({
    ...item,
    label: item.id === id ? label : item.label,
    children: item.children
      ? renameResource(item.children, id, label)
      : undefined,
  }));
}

function defaultIcon(item: SidebarResource, expanded: boolean) {
  const Icon =
    item.kind === "folder" || item.kind === "project"
      ? expanded
        ? FolderOpen
        : Folder
      : item.kind === "bookmark"
          ? Bookmark
          : FileText;
  return <Icon className="size-4" />;
}

function MarqueeLabel({ active, children }: { active: boolean; children: string }) {
  const reduce = useReducedMotion() ?? false;
  const viewportRef = useRef<HTMLSpanElement>(null);
  const labelRef = useRef<HTMLSpanElement>(null);
  const [distance, setDistance] = useState(0);

  useEffect(() => {
    const measure = () => {
      const viewport = viewportRef.current;
      const label = labelRef.current;
      if (!viewport || !label) return;
      setDistance(label.scrollWidth > viewport.clientWidth ? label.scrollWidth + 24 : 0);
    };
    measure();
    const observer = new ResizeObserver(measure);
    if (viewportRef.current) observer.observe(viewportRef.current);
    if (labelRef.current) observer.observe(labelRef.current);
    return () => observer.disconnect();
  }, []);

  const running = active && distance > 0 && !reduce;

  return (
    <span ref={viewportRef} className="block min-w-0 flex-1 overflow-hidden">
      <motion.span
        className="flex w-max items-center gap-6 whitespace-nowrap"
        animate={{ x: running ? [0, -distance] : 0 }}
        transition={
          running
            ? {
                duration: Math.max(2.4, distance / 34),
                ease: "linear",
                repeat: Number.POSITIVE_INFINITY,
                repeatDelay: 2,
              }
            : ROW_REVEAL
        }
      >
        <span ref={labelRef}>{children}</span>
        {running ? <span aria-hidden="true">{children}</span> : null}
      </motion.span>
    </span>
  );
}

function ResourceMenuAction({
  icon: Icon,
  onSelect,
  children,
}: {
  icon: LucideIcon;
  onSelect: () => void;
  children: ReactNode;
}) {
  return (
    <button
      type="button"
      onClick={onSelect}
      className="flex h-8 w-full items-center gap-2 rounded-lg px-2.5 text-left text-xs text-foreground outline-none transition-colors hover:bg-muted focus-visible:bg-muted focus-visible:ring-2 focus-visible:ring-ring"
    >
      <Icon aria-hidden="true" className="size-3.5 shrink-0" />
      <span className="min-w-0 truncate">{children}</span>
    </button>
  );
}

interface ResourceRowProps {
  row: FlatResource;
  active: boolean;
  expanded: boolean;
  focused: boolean;
  draggingId: string | null;
  dropTarget: DropTarget | null;
  menuOpen: boolean;
  moves: SidebarResourceMoveCommands;
  renaming: boolean;
  onDragEnd: () => void;
  onDragOver: (event: DragEvent<HTMLDivElement>, row: FlatResource) => void;
  onDragStart: (event: DragEvent<HTMLDivElement>, id: string) => void;
  onDrop: (event: DragEvent<HTMLDivElement>) => void;
  onFocus: () => void;
  onKeyDown: (event: KeyboardEvent<HTMLDivElement>) => void;
  onMenuOpenChange: (open: boolean) => void;
  onRenameCancel: () => void;
  onRenameCommit: (label: string) => void;
  onRenameStart: () => void;
  onSelect: () => void;
  onToggle: () => void;
  renderIcon?: (item: SidebarResource) => ReactNode;
  renderMenu?: AISidebarProps["renderMenu"];
  setRef: (node: HTMLDivElement | null) => void;
}

function ResourceRow({
  row,
  active,
  expanded,
  focused,
  draggingId,
  dropTarget,
  menuOpen,
  moves,
  renaming,
  onDragEnd,
  onDragOver,
  onDragStart,
  onDrop,
  onFocus,
  onKeyDown,
  onMenuOpenChange,
  onRenameCancel,
  onRenameCommit,
  onRenameStart,
  onSelect,
  onToggle,
  renderIcon,
  renderMenu,
  setRef,
}: ResourceRowProps) {
  const reduce = useReducedMotion() ?? false;
  const canTouch = useTouchCapable();
  const [hovered, setHovered] = useState(false);
  const inputRef = useRef<HTMLInputElement>(null);
  const skipRenameBlurRef = useRef(false);
  const draggedRef = useRef(false);
  const [draft, setDraft] = useState(row.item.label);
  const acceptsChildren = canContain(row.item);
  const isDragging = draggingId === row.item.id;
  const dropPosition = dropTarget?.id === row.item.id ? dropTarget.position : null;

  useEffect(() => {
    if (!renaming) return;
    skipRenameBlurRef.current = false;
    setDraft(row.item.label);
    requestAnimationFrame(() => {
      inputRef.current?.focus();
      inputRef.current?.select();
    });
  }, [renaming, row.item.label]);

  const runFromMenu = (action: () => void) => () => {
    onMenuOpenChange(false);
    action();
  };

  const menu = renderMenu?.(row.item, {
    close: () => onMenuOpenChange(false),
    rename: () => {
      onMenuOpenChange(false);
      onRenameStart();
    },
    moves,
  }) ?? (
    <>
      <ResourceMenuAction icon={Pencil} onSelect={runFromMenu(onRenameStart)}>
        Rename
      </ResourceMenuAction>
      {moves.up || moves.down || moves.into || moves.out ? (
        <div aria-hidden="true" className="my-1 h-px bg-border" />
      ) : null}
      {moves.up ? (
        <ResourceMenuAction icon={ArrowUp} onSelect={runFromMenu(moves.up)}>
          Move up
        </ResourceMenuAction>
      ) : null}
      {moves.down ? (
        <ResourceMenuAction icon={ArrowDown} onSelect={runFromMenu(moves.down)}>
          Move down
        </ResourceMenuAction>
      ) : null}
      {moves.into ? (
        <ResourceMenuAction
          icon={FolderInput}
          onSelect={runFromMenu(moves.into.run)}
        >
          Move into {moves.into.label}
        </ResourceMenuAction>
      ) : null}
      {moves.out ? (
        <ResourceMenuAction icon={Undo2} onSelect={runFromMenu(moves.out)}>
          Move out
        </ResourceMenuAction>
      ) : null}
    </>
  );

  return (
    <motion.div
      ref={setRef}
      layout="position"
      transition={reduce ? { duration: 0 } : SPRING_LAYOUT}
      role="treeitem"
      aria-level={row.depth + 1}
      aria-selected={acceptsChildren ? undefined : active}
      aria-expanded={acceptsChildren ? expanded : undefined}
      aria-disabled={row.item.disabled || undefined}
      tabIndex={focused ? 0 : -1}
      draggable={!row.item.disabled && !renaming}
      data-menu-open={menuOpen || undefined}
      data-drop={dropPosition ?? undefined}
      data-dragging={isDragging || undefined}
      onFocus={onFocus}
      onKeyDown={onKeyDown}
      onClick={(event) => {
        if (
          event.defaultPrevented ||
          draggedRef.current ||
          renaming ||
          row.item.disabled
        )
          return;
        if (acceptsChildren) onToggle();
        else onSelect();
      }}
      onDoubleClick={(event) => {
        if (acceptsChildren || row.item.disabled) return;
        event.preventDefault();
        onRenameStart();
      }}
      onMouseEnter={() => setHovered(true)}
      onMouseLeave={() => setHovered(false)}
      onDragStartCapture={(event) => {
        draggedRef.current = true;
        onDragStart(event, row.item.id);
      }}
      onDragEndCapture={() => {
        onDragEnd();
        requestAnimationFrame(() => {
          draggedRef.current = false;
        });
      }}
      onDragOver={(event) => onDragOver(event, row)}
      onDrop={onDrop}
      className={cn(
        "group/resource relative flex min-h-9 min-w-0 cursor-pointer items-center gap-2.5 rounded-xl pr-3 text-sm outline-none",
        "text-muted-foreground transition-colors hover:bg-muted hover:text-foreground",
        "focus-visible:bg-muted/70 focus-visible:ring-2 focus-visible:ring-ring focus-visible:ring-inset",
        "data-[menu-open=true]:bg-muted data-[menu-open=true]:text-foreground",
        "data-[dragging=true]:opacity-40",
        "data-[drop=inside]:bg-muted data-[drop=inside]:ring-1 data-[drop=inside]:ring-primary/45",
        "data-[drop=before]:before:absolute data-[drop=before]:before:-top-0.5 data-[drop=before]:before:right-2 data-[drop=before]:before:left-2 data-[drop=before]:before:h-0.5 data-[drop=before]:before:rounded-full data-[drop=before]:before:bg-primary",
        "data-[drop=after]:after:absolute data-[drop=after]:after:-bottom-0.5 data-[drop=after]:after:right-2 data-[drop=after]:after:left-2 data-[drop=after]:after:h-0.5 data-[drop=after]:after:rounded-full data-[drop=after]:after:bg-primary",
        !acceptsChildren && active && "bg-muted text-foreground",
        row.item.disabled && "cursor-not-allowed opacity-45",
      )}
      style={{ paddingLeft: `${12 + row.depth * 16}px` }}
    >
      <span aria-hidden="true" className="grid size-5 shrink-0 place-items-center">
        {renderIcon?.(row.item) ?? defaultIcon(row.item, expanded)}
      </span>

      {renaming ? (
        <input
          ref={inputRef}
          value={draft}
          aria-label={`Rename ${row.item.label}`}
          onChange={(event) => setDraft(event.target.value)}
          draggable={false}
          onClick={(event) => event.stopPropagation()}
          onDoubleClick={(event) => event.stopPropagation()}
          onBlur={() => {
            if (!skipRenameBlurRef.current) onRenameCommit(draft);
          }}
          onKeyDown={(event) => {
            event.stopPropagation();
            if (event.key === "Enter") {
              skipRenameBlurRef.current = true;
              onRenameCommit(draft);
            }
            if (event.key === "Escape") {
              skipRenameBlurRef.current = true;
              onRenameCancel();
            }
          }}
          className="mx-1 h-7 min-w-0 flex-1 rounded-md border border-border bg-background px-2 text-sm text-foreground outline-none focus-visible:ring-2 focus-visible:ring-ring"
        />
      ) : (
        <MarqueeLabel active={hovered || menuOpen}>{row.item.label}</MarqueeLabel>
      )}

      {!renaming && !row.item.disabled ? (
        <MorphPopover
          open={menuOpen}
          onOpenChange={onMenuOpenChange}
        >
          <MorphPopoverTrigger>
            <button
              type="button"
              draggable={false}
              tabIndex={-1}
              aria-label={`Actions for ${row.item.label}`}
              onClick={(event) => event.stopPropagation()}
              className={cn(
                "grid size-7 shrink-0 place-items-center rounded-lg outline-none transition-opacity hover:bg-foreground/5 focus-visible:opacity-100 focus-visible:ring-2 focus-visible:ring-ring group-hover/resource:opacity-100 group-data-[menu-open=true]/resource:opacity-100",
                // A finger never hovers, and this menu is the only path to
                // rename and move without a drag — keep it on screen there.
                canTouch ? "opacity-100" : "opacity-0",
              )}
            >
              <MoreHorizontal aria-hidden="true" className="size-4" />
            </button>
          </MorphPopoverTrigger>
          <MorphPopoverContent
            side="bottom"
            align="end"
            sideOffset={8}
            radius={12}
            className="w-40 p-1.5"
          >
            <div data-sidebar-resource-menu={row.item.id}>{menu}</div>
          </MorphPopoverContent>
        </MorphPopover>
      ) : null}
    </motion.div>
  );
}

export function AISidebar({
  items,
  defaultItems = [],
  onItemsChange,
  onMove,
  onMoveError,
  onRename,
  activeId,
  defaultActiveId = null,
  onActiveChange,
  defaultExpandedIds = [],
  renderIcon,
  renderMenu,
  ariaLabel = "Resources",
  className,
}: AISidebarProps) {
  const [internalItems, setInternalItems] = useState(items ?? defaultItems);
  const [internalActiveId, setInternalActiveId] = useState(defaultActiveId);
  const [expandedIds, setExpandedIds] = useState(
    () => new Set(defaultExpandedIds),
  );
  const [focusedId, setFocusedId] = useState<string | null>(
    activeId ?? defaultActiveId,
  );
  const [draggingId, setDraggingId] = useState<string | null>(null);
  const [dropTarget, setDropTarget] = useState<DropTarget | null>(null);
  const [menuOpenId, setMenuOpenId] = useState<string | null>(null);
  const [renamingId, setRenamingId] = useState<string | null>(null);
  const [announcement, setAnnouncement] = useState("");
  const rowRefs = useRef(new Map<string, HTMLDivElement>());
  const movePendingRef = useRef(false);
  const renderedItems = internalItems;
  const selectedId = activeId ?? internalActiveId;

  useEffect(() => {
    if (items) setInternalItems(items);
  }, [items]);

  const flat = useMemo(
    () => flattenResources(renderedItems, expandedIds),
    [expandedIds, renderedItems],
  );

  // Which row carries the roving tabindex is resolved during render, never in
  // a passive effect: an effect lands after the browser paints, so the first
  // commit — and, on a server-rendered page, the markup itself — would have no
  // tabbable row and Tab would skip the whole tree. The same hole opens again
  // whenever a collapse or a rolled-back move takes the focused row out of it.
  const focusedRow =
    focusedId !== null && flat.some((row) => row.item.id === focusedId)
      ? focusedId
      : (flat[0]?.item.id ?? null);
  if (focusedId !== focusedRow) setFocusedId(focusedRow);

  useEffect(() => {
    if (!menuOpenId) return;
    const frame = requestAnimationFrame(() => {
      const menus = Array.from(
        document.querySelectorAll<HTMLElement>("[data-sidebar-resource-menu]"),
      );
      menus
        .find((menu) => menu.dataset.sidebarResourceMenu === menuOpenId)
        ?.querySelector<HTMLElement>("button, a[href]")
        ?.focus();
    });
    return () => cancelAnimationFrame(frame);
  }, [menuOpenId]);

  const updateItems = useCallback(
    (next: SidebarResource[]) => {
      setInternalItems(next);
      onItemsChange?.(next);
    },
    [onItemsChange],
  );

  const performMove = useCallback(
    async (move: SidebarResourceMove) => {
      if (movePendingRef.current) {
        setAnnouncement("Wait for the current move to finish.");
        return;
      }
      const before = renderedItems;
      const next = moveResource(before, move);
      if (!next || next === before) return;

      movePendingRef.current = true;
      updateItems(next);
      setDropTarget(null);
      setDraggingId(null);
      const moved = findResource(before, move.itemId);
      const target = move.targetId ? findResource(before, move.targetId) : null;
      setAnnouncement(
        target
          ? `Moved ${moved?.label ?? "item"} ${move.position} ${target.label}.`
          : `Moved ${moved?.label ?? "item"} to the top level.`,
      );

      try {
        await onMove?.(move);
      } catch (error) {
        updateItems(before);
        setAnnouncement(`Move failed. ${moved?.label ?? "Item"} was restored.`);
        onMoveError?.(error, move);
      } finally {
        movePendingRef.current = false;
      }
    },
    [onMove, onMoveError, renderedItems, updateItems],
  );

  const focusRow = useCallback((id: string) => {
    setFocusedId(id);
    requestAnimationFrame(() => rowRefs.current.get(id)?.focus());
  }, []);

  const select = useCallback(
    (id: string) => {
      if (activeId === undefined) setInternalActiveId(id);
      onActiveChange?.(id);
    },
    [activeId, onActiveChange],
  );

  const toggle = useCallback((id: string) => {
    setExpandedIds((current) => {
      const next = new Set(current);
      if (next.has(id)) next.delete(id);
      else next.add(id);
      return next;
    });
  }, []);

  // The same four moves `Alt+Shift+Arrow` performs, handed to the row menu so
  // they survive on a device with no drag and no modifier keys.
  const moveCommands = useCallback(
    (row: FlatResource): SidebarResourceMoveCommands => {
      if (row.item.disabled) return {};
      const index = flat.findIndex(({ item }) => item.id === row.item.id);
      const previous = flat[index - 1];
      const next = flat[index + 1];
      const parentId = row.parentId;
      const commands: SidebarResourceMoveCommands = {};

      if (previous) {
        commands.up = () =>
          void performMove({
            itemId: row.item.id,
            targetId: previous.item.id,
            position: "before",
          });
      }
      if (next) {
        commands.down = () =>
          void performMove({
            itemId: row.item.id,
            targetId: next.item.id,
            position: "after",
          });
      }
      // Only offer the reparent when it lands somewhere new — the row above a
      // folder's first child is the folder it already lives in.
      if (previous && canContain(previous.item) && previous.item.id !== parentId) {
        commands.into = {
          label: previous.item.label,
          run: () => {
            setExpandedIds((current) => new Set(current).add(previous.item.id));
            void performMove({
              itemId: row.item.id,
              targetId: previous.item.id,
              position: "inside",
            });
          },
        };
      }
      if (parentId) {
        commands.out = () =>
          void performMove({
            itemId: row.item.id,
            targetId: parentId,
            position: "after",
          });
      }

      return commands;
    },
    [flat, performMove],
  );

  const handleKeyDown = useCallback(
    (event: KeyboardEvent<HTMLDivElement>, row: FlatResource) => {
      const index = flat.findIndex(({ item }) => item.id === row.item.id);
      const previous = flat[index - 1];
      const next = flat[index + 1];
      const moveModifier = event.altKey && event.shiftKey;

      if (event.key === "ArrowDown" && !moveModifier && next) {
        event.preventDefault();
        focusRow(next.item.id);
        return;
      }
      if (event.key === "ArrowUp" && !moveModifier && previous) {
        event.preventDefault();
        focusRow(previous.item.id);
        return;
      }
      if (event.key === "Home" && flat[0]) {
        event.preventDefault();
        focusRow(flat[0].item.id);
        return;
      }
      if (event.key === "End" && flat.at(-1)) {
        event.preventDefault();
        focusRow(flat.at(-1)?.item.id ?? row.item.id);
        return;
      }

      if (row.item.disabled) {
        if (event.key === "ArrowLeft" && row.parentId) {
          event.preventDefault();
          focusRow(row.parentId);
        } else if (
          moveModifier ||
          ["ArrowRight", "Enter", " ", "F2", "ContextMenu"].includes(
            event.key,
          ) ||
          (event.shiftKey && event.key === "F10")
        ) {
          event.preventDefault();
        }
        return;
      }

      if (moveModifier && event.key === "ArrowUp" && previous) {
        event.preventDefault();
        void performMove({ itemId: row.item.id, targetId: previous.item.id, position: "before" });
        return;
      }
      if (moveModifier && event.key === "ArrowDown" && next) {
        event.preventDefault();
        void performMove({ itemId: row.item.id, targetId: next.item.id, position: "after" });
        return;
      }
      if (moveModifier && event.key === "ArrowRight" && previous && canContain(previous.item)) {
        event.preventDefault();
        setExpandedIds((current) => new Set(current).add(previous.item.id));
        void performMove({ itemId: row.item.id, targetId: previous.item.id, position: "inside" });
        return;
      }
      if (moveModifier && event.key === "ArrowLeft" && row.parentId) {
        event.preventDefault();
        void performMove({ itemId: row.item.id, targetId: row.parentId, position: "after" });
        return;
      }

      if (event.key === "ArrowRight" && canContain(row.item)) {
        event.preventDefault();
        if (!expandedIds.has(row.item.id)) toggle(row.item.id);
        else if (next?.parentId === row.item.id) focusRow(next.item.id);
      } else if (event.key === "ArrowLeft") {
        event.preventDefault();
        if (expandedIds.has(row.item.id)) toggle(row.item.id);
        else if (row.parentId) focusRow(row.parentId);
      } else if (event.key === "Enter" || event.key === " ") {
        event.preventDefault();
        if (canContain(row.item)) toggle(row.item.id);
        else select(row.item.id);
      } else if (event.key === "F2") {
        event.preventDefault();
        setRenamingId(row.item.id);
      } else if (event.key === "ContextMenu" || (event.shiftKey && event.key === "F10")) {
        event.preventDefault();
        setMenuOpenId(row.item.id);
      }
    },
    [expandedIds, flat, focusRow, performMove, select, toggle],
  );

  return (
    <>
      <div
      role="tree"
      aria-label={ariaLabel}
      aria-multiselectable="false"
      onDragOver={(event) => {
        if (!draggingId || event.target !== event.currentTarget) return;
        event.preventDefault();
        setDropTarget({ id: null, position: "after" });
      }}
      onDrop={(event) => {
        event.preventDefault();
        if (draggingId && dropTarget) {
          void performMove({
            itemId: draggingId,
            targetId: dropTarget.id,
            position: dropTarget.position,
          });
        }
      }}
      className={cn(
        "relative flex min-w-0 flex-col gap-0.5 [overflow-anchor:none] group-data-[state=collapsed]/sidebar:hidden",
        draggingId && "select-none pb-9",
        className,
      )}
    >
      <AnimatePresence initial={false}>
        {flat.map((row) => (
          <ResourceRow
            key={row.item.id}
            row={row}
            active={selectedId === row.item.id}
            expanded={expandedIds.has(row.item.id)}
            focused={focusedRow === row.item.id}
            draggingId={draggingId}
            dropTarget={dropTarget}
            menuOpen={menuOpenId === row.item.id}
            moves={moveCommands(row)}
            renaming={renamingId === row.item.id}
            onFocus={() => setFocusedId(row.item.id)}
            onSelect={() => select(row.item.id)}
            onToggle={() => toggle(row.item.id)}
            onKeyDown={(event) => handleKeyDown(event, row)}
            onRenameStart={() => setRenamingId(row.item.id)}
            onRenameCancel={() => setRenamingId(null)}
            onRenameCommit={(label) => {
              const trimmed = label.trim();
              setRenamingId(null);
              if (!trimmed || trimmed === row.item.label) return;
              const before = renderedItems;
              updateItems(renameResource(before, row.item.id, trimmed));
              void Promise.resolve(onRename?.(row.item, trimmed)).catch(() => {
                updateItems(before);
                setAnnouncement(`Rename failed. ${row.item.label} was restored.`);
              });
            }}
            onMenuOpenChange={(open) => {
              setMenuOpenId(open ? row.item.id : null);
              if (!open) focusRow(row.item.id);
            }}
            onDragStart={(event, id) => {
              setDraggingId(id);
              event.dataTransfer.effectAllowed = "move";
              event.dataTransfer.setData("text/plain", id);
            }}
            onDragEnd={() => {
              setDraggingId(null);
              setDropTarget(null);
            }}
            onDragOver={(event, targetRow) => {
              if (!draggingId || draggingId === targetRow.item.id) return;
              const source = findResource(renderedItems, draggingId);
              if (source && containsResource(source, targetRow.item.id)) return;
              event.preventDefault();
              event.stopPropagation();
              const rect = event.currentTarget.getBoundingClientRect();
              const ratio = (event.clientY - rect.top) / rect.height;
              const position =
                !targetRow.item.disabled &&
                canContain(targetRow.item) &&
                ratio >= 0.25 &&
                ratio <= 0.75
                  ? "inside"
                  : ratio < 0.5
                    ? "before"
                    : "after";
              setDropTarget({ id: targetRow.item.id, position });
            }}
            onDrop={(event) => {
              event.preventDefault();
              event.stopPropagation();
              if (draggingId && dropTarget) {
                void performMove({
                  itemId: draggingId,
                  targetId: dropTarget.id,
                  position: dropTarget.position,
                });
              }
            }}
            renderIcon={renderIcon}
            renderMenu={renderMenu}
            setRef={(node) => {
              if (node) rowRefs.current.set(row.item.id, node);
              else rowRefs.current.delete(row.item.id);
            }}
          />
        ))}
      </AnimatePresence>

      {draggingId ? (
        <div
          aria-hidden="true"
          data-active={dropTarget?.id === null || undefined}
          className="absolute inset-x-1 bottom-0 flex h-8 items-center justify-center rounded-lg border border-dashed border-border text-[10px] text-muted-foreground data-[active=true]:border-primary/50 data-[active=true]:bg-muted data-[active=true]:text-foreground"
        >
          Move to top level
        </div>
      ) : null}

      </div>
      <span className="sr-only" aria-live="polite">
        {announcement}
      </span>
    </>
  );
}

"use client";

import {
  AnimatePresence,
  motion,
  animate,
  useMotionValue,
  usePresence,
  useReducedMotion,
} from "motion/react";
import {
  cloneElement,
  createContext,
  isValidElement,
  type ReactElement,
  type ReactNode,
  type Ref,
  useCallback,
  useContext,
  useEffect,
  useId,
  useMemo,
  useRef,
  useState,
} from "react";
import { createPortal } from "react-dom";
import { usePopoverPortalPosition } from "@/components/motion/popover-position";
import { EASE_OUT, SPRING_PANEL } from "@/lib/ease";
import { cn } from "@/lib/utils";

type Side = "top" | "bottom";
type Align = "start" | "end";

type MorphContextValue = {
  open: boolean;
  setOpen: (open: boolean) => void;
  toggle: () => void;
  triggerId: string;
  contentId: string;
  /** The element the panel measures against — see `registerTrigger`. */
  triggerRef: React.MutableRefObject<HTMLElement | null>;
  registerTrigger: (node: HTMLElement | null) => void;
  contentRef: React.MutableRefObject<HTMLDivElement | null>;
};

const MorphContext = createContext<MorphContextValue | null>(null);

function useMorphContext(component: string) {
  const ctx = useContext(MorphContext);
  if (!ctx) throw new Error(`${component} must be used within <MorphPopover>`);
  return ctx;
}

export interface MorphPopoverProps {
  children: ReactNode;
  /** Controlled open state. */
  open?: boolean;
  /** Uncontrolled initial open state. */
  defaultOpen?: boolean;
  onOpenChange?: (open: boolean) => void;
  className?: string;
}

/**
 * A popover whose panel morphs open from the trigger corner: it's laid out at
 * full size but clipped to the corner nearest the trigger, then unclips as one
 * piece. Closes on outside pointer / Escape. Controlled or uncontrolled.
 */
export function MorphPopover({
  children,
  open: controlledOpen,
  defaultOpen = false,
  onOpenChange,
  className,
}: MorphPopoverProps) {
  const baseId = useId();
  const [root, setRoot] = useState<HTMLDivElement | null>(null);
  const [trigger, setTrigger] = useState<HTMLElement | null>(null);
  const contentRef = useRef<HTMLDivElement | null>(null);
  const [internalOpen, setInternalOpen] = useState(defaultOpen);
  const controlled = controlledOpen !== undefined;
  const open = controlled ? controlledOpen : internalOpen;

  const setOpen = useCallback(
    (next: boolean) => {
      if (!controlled) setInternalOpen(next);
      onOpenChange?.(next);
    },
    [controlled, onOpenChange],
  );
  const toggle = useCallback(() => setOpen(!open), [setOpen, open]);

  // A trigger normally registers itself through MorphPopoverTrigger. It can't
  // when something else already clones the element — a Tooltip wrapping the
  // button, say — and an unregistered trigger leaves the panel with nothing to
  // measure against, so it renders permanently invisible. The root boxes the
  // trigger exactly (the content portals out of it), so it stands in until a
  // real trigger registers, and stands in again if that one unmounts. Both are
  // state, so a trigger arriving while the panel is open re-anchors it.
  const anchorRef = useMemo<React.MutableRefObject<HTMLElement | null>>(
    () => ({ current: trigger ?? root }),
    [root, trigger],
  );

  // The panel is a `role="dialog"` and goes inert the moment it closes, so
  // focus cannot be left sitting inside it: a dismissal hands it back to the
  // trigger, the way the ARIA dialog pattern asks. A pointer dismissal takes
  // the focus onward itself when it lands on something focusable — this only
  // catches the case where it would otherwise be stranded. When no trigger has
  // registered, the root anchor stands in only if it can actually hold focus;
  // there is nowhere better than where the keyboard already is, so leave it.
  const close = useCallback(() => {
    setOpen(false);
    const focused = document.activeElement;
    const inPanel =
      focused instanceof HTMLElement && contentRef.current?.contains(focused);
    if (!inPanel) return;
    const restore = trigger ?? (root && root.tabIndex >= 0 ? root : null);
    restore?.focus();
  }, [root, setOpen, trigger]);

  useEffect(() => {
    if (!open) return;
    const onKey = (e: KeyboardEvent) => e.key === "Escape" && close();
    const onPointer = (e: PointerEvent) => {
      const target = e.target as Node;
      if (
        root &&
        !root.contains(target) &&
        !contentRef.current?.contains(target)
      )
        close();
    };
    window.addEventListener("keydown", onKey);
    window.addEventListener("pointerdown", onPointer);
    return () => {
      window.removeEventListener("keydown", onKey);
      window.removeEventListener("pointerdown", onPointer);
    };
  }, [open, root, close]);

  const ctx = useMemo<MorphContextValue>(
    () => ({
      open,
      setOpen,
      toggle,
      triggerId: `${baseId}-trigger`,
      contentId: `${baseId}-content`,
      triggerRef: anchorRef,
      registerTrigger: setTrigger,
      contentRef,
    }),
    [open, setOpen, toggle, baseId, anchorRef],
  );

  return (
    <MorphContext.Provider value={ctx}>
      <div ref={setRoot} className={cn("relative inline-flex", className)}>
        {children}
      </div>
    </MorphContext.Provider>
  );
}

export interface MorphPopoverTriggerProps {
  children: ReactElement;
}

function mergeRefs<T>(...refs: Array<Ref<T> | undefined>) {
  return (node: T | null) => {
    for (const ref of refs) {
      if (typeof ref === "function") ref(node);
      else if (ref && typeof ref === "object")
        (ref as React.MutableRefObject<T | null>).current = node;
    }
  };
}

/** Wraps a single element, toggling the popover on click. */
export function MorphPopoverTrigger({ children }: MorphPopoverTriggerProps) {
  const ctx = useMorphContext("MorphPopoverTrigger");
  const child = children as ReactElement<Record<string, unknown>>;
  const childOnClick = child?.props?.onClick as
    | ((e: unknown) => void)
    | undefined;
  const childRef = (child?.props as { ref?: Ref<HTMLElement> } | undefined)
    ?.ref;
  // Register once per actual ref change, not once per open-state render.
  const mergedRef = useMemo(
    () => mergeRefs(childRef, ctx.registerTrigger),
    [childRef, ctx.registerTrigger],
  );
  if (!isValidElement(children)) return children;

  return cloneElement(child, {
    id: ctx.triggerId,
    ref: mergedRef,
    onClick: (e: unknown) => {
      childOnClick?.(e);
      ctx.toggle();
    },
    "aria-haspopup": "dialog",
    "aria-expanded": ctx.open,
    "aria-controls": ctx.open ? ctx.contentId : undefined,
  });
}

const originFor = (side: Side, align: Align) =>
  `${side === "bottom" ? "top" : "bottom"} ${align === "end" ? "right" : "left"}`;

// A clip that hides everything but the corner nearest the trigger, so the
// panel appears to grow out of it. inset(top right bottom left).
function clipAt(side: Side, align: Align, radius: number, inset: number) {
  const top = side === "bottom" ? "0%" : `${inset}%`;
  const bottom = side === "bottom" ? `${inset}%` : "0%";
  const right = align === "end" ? "0%" : `${inset}%`;
  const left = align === "end" ? `${inset}%` : "0%";
  return `inset(${top} ${right} ${bottom} ${left} round ${radius}px)`;
}

// Preserve the original spring character on the wrapper, but tween the complex
// clip-path so it cannot snap when the spring resolves its final distance.
const MORPH_CLIP_TRANSITION = { duration: 0.32, ease: EASE_OUT } as const;

export interface MorphPopoverContentProps {
  children: ReactNode;
  side?: Side;
  align?: Align;
  /** Gap between trigger and panel, in px. Default 8. */
  sideOffset?: number;
  /** Panel corner radius, in px. Default 16. */
  radius?: number;
  /** Draw the surface shadow. Default true. */
  shadow?: boolean;
  /** Runs after the portalled surface is positioned and visible. */
  onOpenAutoFocus?: (content: HTMLDivElement) => void;
  className?: string;
}

export function MorphPopoverContent(props: MorphPopoverContentProps) {
  const ctx = useMorphContext("MorphPopoverContent");
  const [portalReady, setPortalReady] = useState(false);
  useEffect(() => setPortalReady(true), []);
  if (!portalReady) return null;
  return createPortal(
    <AnimatePresence>
      {ctx.open && <MorphPopoverSurface {...props} />}
    </AnimatePresence>,
    document.body,
  );
}

// Measurement belongs to the mounted portal session: reopening must not start
// an entrance at the previous session's coordinates before measuring this one.
function MorphPopoverSurface({
  children,
  side = "bottom",
  align = "end",
  sideOffset = 8,
  radius = 16,
  shadow = true,
  onOpenAutoFocus,
  className,
}: MorphPopoverContentProps) {
  const ctx = useMorphContext("MorphPopoverContent");
  const reduce = useReducedMotion() ?? false;
  const [isPresent, safeToRemove] = usePresence();
  const layout = usePopoverPortalPosition(
    ctx.triggerRef,
    ctx.contentRef,
    isPresent,
  );

  const preferredLeft = layout
    ? align === "end"
      ? layout.trigger.left + layout.trigger.width - layout.content.width
      : layout.trigger.left
    : 0;
  // Keep larger compositions, such as calendars, inside the viewport. Prefer
  // the requested side, then use the roomier side when it cannot fit there.
  const gutter = 12;
  const below = layout
    ? Math.max(
        0,
        window.innerHeight -
          layout.trigger.top -
          layout.trigger.height -
          sideOffset -
          gutter,
      )
    : 0;
  const above = layout
    ? Math.max(0, layout.trigger.top - sideOffset - gutter)
    : 0;
  const requestedSpace = side === "bottom" ? below : above;
  const otherSpace = side === "bottom" ? above : below;
  const resolvedSide =
    layout &&
    layout.content.height > requestedSpace &&
    otherSpace > requestedSpace
      ? side === "bottom"
        ? "top"
        : "bottom"
      : side;
  const availableHeight = resolvedSide === "bottom" ? below : above;
  const left = layout
    ? Math.max(
        gutter,
        Math.min(
          preferredLeft,
          window.innerWidth - layout.content.width - gutter,
        ),
      )
    : 0;
  const top = layout
    ? resolvedSide === "bottom"
      ? layout.trigger.top + layout.trigger.height + sideOffset
      : Math.max(
          gutter,
          layout.trigger.top - layout.content.height - sideOffset,
        )
    : 0;

  // Both directions travel between the exact same hidden/show states. Exit
  // targets "hidden" directly instead of introducing separate choreography.
  const wrap = reduce
    ? undefined
    : {
        hidden: { scale: 0.96, transition: SPRING_PANEL },
        show: { scale: 1, transition: SPRING_PANEL },
      };
  const clip = reduce
    ? undefined
    : {
        hidden: {
          clipPath: clipAt(resolvedSide, align, radius, 92),
          transition: MORPH_CLIP_TRANSITION,
        },
        show: {
          clipPath: clipAt(resolvedSide, align, radius, 0),
          transition: MORPH_CLIP_TRANSITION,
        },
      };
  // Animate the value directly so opacity stays in the inline style throughout
  // the entrance. A native opacity animation can expose the initial inline 0
  // for a frame when it finishes, before Motion writes the final value.
  const opacity = useMotionValue(0);
  const ready = layout !== null;
  const focusedOnOpen = useRef(false);
  useEffect(() => {
    if (
      !ready ||
      !isPresent ||
      focusedOnOpen.current ||
      !ctx.contentRef.current
    )
      return;
    focusedOnOpen.current = true;
    onOpenAutoFocus?.(ctx.contentRef.current);
  }, [ready, isPresent, ctx.contentRef, onOpenAutoFocus]);
  useEffect(() => {
    if (!ready) {
      if (!isPresent) safeToRemove?.();
      return;
    }
    const animation = animate(opacity, isPresent ? 1 : 0, {
      ...(reduce ? { duration: 0.12 } : SPRING_PANEL),
      onComplete: () => {
        if (!isPresent) safeToRemove?.();
      },
    });
    return () => animation.stop();
  }, [opacity, ready, isPresent, reduce, safeToRemove]);

  return (
    <motion.div
      data-morph-popover-portal=""
      inert={!isPresent}
      // Wrapper carries the shadow as a drop-shadow filter, which hugs the
      // clipped shape below (box-shadow would just get clipped away).
      variants={wrap}
      initial="hidden"
      animate={layout ? "show" : "hidden"}
      exit="hidden"
      style={{
        left,
        top,
        opacity,
        pointerEvents: isPresent ? "auto" : "none",
        visibility: layout ? "visible" : "hidden",
        transformOrigin: originFor(resolvedSide, align),
      }}
      className={cn(
        "fixed z-[9999]",
        shadow && "[filter:drop-shadow(0_10px_18px_rgba(0,0,0,0.14))]",
      )}
    >
      <motion.div
        ref={ctx.contentRef}
        id={ctx.contentId}
        role="dialog"
        aria-labelledby={ctx.triggerId}
        variants={clip}
        style={{
          borderRadius: radius,
          maxHeight: layout ? availableHeight : undefined,
          overflowY: "auto",
        }}
        className={cn(
          "overflow-hidden border border-border bg-background",
          className,
        )}
      >
        {children}
      </motion.div>
    </motion.div>
  );
}

// Shared motion tokens. Easing curves mirror the CSS custom properties in
// globals.css; springs are the canonical physics used across components.
// Strong custom variants — defaults like `ease-in`/`ease-out` feel weak.

export const EASE_OUT = [0.16, 1, 0.3, 1] as const;
export const EASE_IN_OUT = [0.77, 0, 0.175, 1] as const;
export const EASE_DRAWER = [0.32, 0.72, 0, 1] as const;

/** CSS string form of EASE_OUT for inline style transitions. */
export const EASE_OUT_CSS = "cubic-bezier(0.16, 1, 0.3, 1)";

/** Press feedback on buttons and other tappable surfaces. */
export const SPRING_PRESS = {
  type: "spring",
  stiffness: 500,
  damping: 30,
  mass: 0.6,
} as const;

/** Content swaps — label/icon slots trading places inside a control. */
export const SPRING_SWAP = {
  type: "spring",
  stiffness: 460,
  damping: 30,
  mass: 0.55,
} as const;

/** Overlay panel entrances — modals and sheets summoned by pointer. */
export const SPRING_PANEL = {
  type: "spring",
  stiffness: 420,
  damping: 40,
  mass: 0.5,
} as const;

/** Shared-layout glides — pills, indicators and panels morphing between positions. */
export const SPRING_LAYOUT = {
  type: "spring",
  stiffness: 360,
  damping: 32,
  mass: 0.6,
} as const;

/** Cursor-follow physics for decorative mouse tracking (magnetic, tilt, dock). */
export const SPRING_MOUSE = {
  stiffness: 200,
  damping: 15,
  mass: 0.3,
} as const;

/** Dragged handles and fills (sliders) — critically damped `useSpring` config,
 * so the value follows the pointer butterily and never rebounds off an end. */
export const SPRING_GLIDE = {
  stiffness: 700,
  damping: 50,
  mass: 0.5,
} as const;

"use client";

import { useEffect, useState } from "react";

/**
 * Returns true on devices that can be touched, whatever else they claim.
 *
 * This is not the inverse of `useHoverCapable`: iPadOS Safari browses
 * desktop-class and answers `(hover: hover) and (pointer: fine)` with true
 * while a finger is the only input there is, so anything that treats
 * hover-capable as "no touch here" strands every iPad. Gate the *touch path*
 * of an interaction on this hook and leave hover-only polish on
 * `useHoverCapable`, so a component that opens on hover also opens on tap.
 */
export function useTouchCapable() {
  const [canTouch, setCanTouch] = useState(false);

  useEffect(() => {
    if (typeof window === "undefined") return;
    const mq = window.matchMedia?.("(any-pointer: coarse)");
    // iPadOS disguises its pointer media queries; maxTouchPoints it reports
    // honestly, which is what makes it the standard iPad tell.
    const update = () =>
      setCanTouch(Boolean(mq?.matches) || navigator.maxTouchPoints > 0);
    update();
    mq?.addEventListener?.("change", update);
    return () => mq?.removeEventListener?.("change", update);
  }, []);

  return canTouch;
}

import { clsx, type ClassValue } from "clsx"
import { twMerge } from "tailwind-merge"

export function cn(...inputs: ClassValue[]) {
  return twMerge(clsx(inputs))
}

"use client";

import {
  type MutableRefObject,
  useCallback,
  useLayoutEffect,
  useState,
} from "react";

export type PortalLayout = {
  trigger: {
    left: number;
    top: number;
    width: number;
    height: number;
  };
  content: {
    width: number;
    height: number;
  };
};

function sameLayout(a: PortalLayout | null, b: PortalLayout) {
  return (
    a?.trigger.left === b.trigger.left &&
    a.trigger.top === b.trigger.top &&
    a.trigger.width === b.trigger.width &&
    a.trigger.height === b.trigger.height &&
    a.content.width === b.content.width &&
    a.content.height === b.content.height
  );
}

/** Measures a trigger and portalled panel in viewport coordinates. */
export function usePopoverPortalPosition<
  TriggerElement extends HTMLElement,
  ContentElement extends HTMLElement,
>(
  triggerRef: MutableRefObject<TriggerElement | null>,
  contentRef: MutableRefObject<ContentElement | null>,
  active: boolean,
) {
  const [layout, setLayout] = useState<PortalLayout | null>(null);

  const update = useCallback(() => {
    const trigger = triggerRef.current;
    const content = contentRef.current;
    if (!trigger || !content) return;

    const rect = trigger.getBoundingClientRect();
    const next: PortalLayout = {
      trigger: {
        left: rect.left,
        top: rect.top,
        width: rect.width,
        height: rect.height,
      },
      content: {
        width: content.offsetWidth,
        height: content.offsetHeight,
      },
    };
    setLayout((current) => (sameLayout(current, next) ? current : next));
  }, [contentRef, triggerRef]);

  useLayoutEffect(() => {
    update();
    if (!active) return;

    const trigger = triggerRef.current;
    const content = contentRef.current;
    const observer = new ResizeObserver(update);
    if (trigger) observer.observe(trigger);
    if (content) observer.observe(content);

    window.addEventListener("scroll", update, true);
    window.addEventListener("resize", update);
    return () => {
      observer.disconnect();
      window.removeEventListener("scroll", update, true);
      window.removeEventListener("resize", update);
    };
  }, [active, contentRef, triggerRef, update]);

  return layout;
}