Animated Avatar Group

// 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 only on devices that have a true hover (mouse / trackpad).
 * Touch devices fire phantom `:hover` on tap that sticks until tap-elsewhere
 * — gate hover-only effects (scale lifts, magnetic pulls) behind this.
 */
export function useHoverCapable() {
  const [canHover, setCanHover] = useState(false);

  useEffect(() => {
    if (typeof window === "undefined" || !window.matchMedia) return;
    const mq = window.matchMedia("(hover: hover) and (pointer: fine)");
    const update = () => setCanHover(mq.matches);
    update();
    mq.addEventListener?.("change", update);
    return () => mq.removeEventListener?.("change", update);
  }, []);

  return canHover;
}

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

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

"use client";

import { type RefObject, useEffect } from "react";

/**
 * What the dismissing gesture does to the control it landed on.
 *
 * `"pass-through"` is the platform norm (native popover light-dismiss): the
 * tap closes the overlay *and* activates whatever was under it. Use
 * `"consume"` where the open overlay sits over or beside controls that would
 * be costly to trigger by accident — the dismissal then swallows the
 * activation too, so the gesture only closes.
 */
export type DismissBehavior = "pass-through" | "consume";

export interface DismissOptions {
  /** Default `"pass-through"`. */
  behavior?: DismissBehavior;
  /** Dismiss on Escape as well. Default true. */
  escape?: boolean;
  /** Return true for an outside target that should *not* dismiss. Must be stable. */
  ignore?: (target: Element) => boolean;
}

/**
 * What every currently open dismiss scope counts as inside itself. A consumed
 * dismissal reads this to tell a stray gesture from one that belongs to an
 * overlay in front of it: overlays have no shared z-order to consult, but the
 * one the gesture landed in has said as much by registering it.
 */
const openScopes = new Set<(target: Element) => boolean>();

function claimedByAnotherScope(
  self: (target: Element) => boolean,
  target: Element,
) {
  for (const scope of openScopes) {
    if (scope !== self && scope(target)) return true;
  }
  return false;
}

// preventDefault on pointerdown does not suppress the click that follows, so
// consuming a gesture means swallowing that click itself. The swallower
// deliberately outlives the effect that installed it — the dismissal it
// belongs to has already unmounted or re-rendered by the time the click lands.
// It releases on that click, or on the next gesture if the pointer is dragged
// away and no click ever arrives, so it can never eat a later one. A keydown
// releases it too: a gesture that ends with neither a click nor a cancel would
// otherwise leave it armed, and the click Enter synthesizes on some focused
// control is not the one this dismissal was owed.
function consumeActivation(source: Event) {
  const swallow = (event: MouseEvent) => {
    event.preventDefault();
    event.stopPropagation();
    release();
  };
  const restart = (event: Event) => {
    if (event !== source) release();
  };
  const release = () => {
    window.removeEventListener("click", swallow, true);
    window.removeEventListener("pointerdown", restart, true);
    window.removeEventListener("pointercancel", restart, true);
    window.removeEventListener("keydown", release, true);
  };
  window.addEventListener("click", swallow, true);
  window.addEventListener("pointerdown", restart, true);
  window.addEventListener("pointercancel", restart, true);
  window.addEventListener("keydown", release, true);
}

/**
 * Close an open overlay on Escape or a pointerdown outside `ref`. Pass `null`
 * for `ref` when what counts as inside isn't one element, and say so with
 * `ignore` instead.
 *
 * The pointerdown listener is capture-phase: a bubble-phase one is blinded by
 * any handler in between that stops propagation, and an overlay cannot know
 * what it is layered over. `onDismiss` and `ignore` must be stable (wrap in
 * useCallback) so the listeners aren't re-bound every render while open.
 */
export function useDismiss(
  open: boolean,
  onDismiss: () => void,
  ref: RefObject<HTMLElement | SVGElement | null> | null,
  {
    behavior = "pass-through",
    escape: dismissOnEscape = true,
    ignore,
  }: DismissOptions = {},
) {
  useEffect(() => {
    if (!open) return;
    const inside = (target: Element) =>
      Boolean(ref?.current?.contains(target)) || Boolean(ignore?.(target));
    const onKey = (event: KeyboardEvent) => {
      if (dismissOnEscape && event.key === "Escape") onDismiss();
    };
    const onPointer = (event: PointerEvent) => {
      const target = event.target as Element | null;
      if (!target || inside(target)) return;
      // Outside this overlay, but inside one that is also open: the gesture is
      // that overlay's to answer, and swallowing its click from behind would
      // cost the user the control they actually aimed at.
      if (behavior === "consume" && !claimedByAnotherScope(inside, target)) {
        consumeActivation(event);
      }
      onDismiss();
    };
    openScopes.add(inside);
    window.addEventListener("keydown", onKey);
    window.addEventListener("pointerdown", onPointer, true);
    return () => {
      openScopes.delete(inside);
      window.removeEventListener("keydown", onKey);
      window.removeEventListener("pointerdown", onPointer, true);
    };
  }, [open, onDismiss, ref, behavior, dismissOnEscape, ignore]);
}

"use client";

import { useMemo, useRef } from "react";
import { isHoveringPointer } from "@/lib/touch";

interface BoundaryEvent {
  pointerId: number;
  pointerType: string;
  buttons: number;
}

export interface HoverGesture {
  /** True when this enter starts a hover: the pointer arrived resting, not pressing. */
  enter: (event: BoundaryEvent) => boolean;
  /** True when this leave ends a hover that entered as one. */
  leave: (event: BoundaryEvent) => boolean;
}

/**
 * Pairs a surface's enter with its leave, per pointer.
 *
 * `isHoveringPointer` answers the question the *enter* asks — is this pointer
 * resting on the surface or pressing it — and both boundary cases go wrong if
 * the leave is asked the same question again:
 *
 * - A pen with no hover never rests. It arrives in contact, taps, and the spec
 *   then requires its boundary events after `pointerup`, so the leave carries
 *   `buttons: 0` and reads as a mouse gliding off. Hover teardown then undid
 *   the tap — the panel the pen had just opened closed under it.
 * - A mouse pressed on the surface and dragged off leaves with `buttons: 1`.
 *   Skipping teardown there strands the surface open: the release happens
 *   outside, and no second leave ever comes.
 *
 * So the state a hover holds is released by the pointer that took it, whatever
 * the buttons say at the boundary, and a pointer that arrived in contact never
 * took it in the first place. Contact is the exception tracked here, not
 * hover: a leave from a pointer this surface never saw enter — mounted under
 * the cursor, say — still counts, since the alternative is state with no way
 * out.
 */
export function useHoverGesture(): HoverGesture {
  const contact = useRef(new Set<number>());

  return useMemo(
    () => ({
      enter: (event) => {
        if (isHoveringPointer(event)) {
          contact.current.delete(event.pointerId);
          return true;
        }
        contact.current.add(event.pointerId);
        return false;
      },
      leave: (event) => {
        const arrivedInContact = contact.current.delete(event.pointerId);
        return !arrivedInContact && event.pointerType !== "touch";
      },
    }),
    [],
  );
}

"use client";

import { useMemo, useRef } from "react";

/** What a pointerdown recorded, read back by the click that ends its gesture. */
export interface TapRecord<S> {
  /** Which input started the gesture. */
  pointerType: string;
  /** What the surface was showing when it started. */
  state: S;
}

export interface TapGesture<S> {
  /** Record the gesture a pointerdown starts, with the state it starts in. */
  start: (event: { pointerType: string }, state: S) => void;
  /** Read the record and clear it. `null` when no pointer is behind this click. */
  take: () => TapRecord<S> | null;
  /** Drop the record: this gesture will never spend it on a click. */
  drop: () => void;
}

/**
 * The pointer gesture behind a click, recorded where the click cannot report
 * it. A `click` carries no `pointerType` in the engines that matter, so the
 * `pointerdown` before it is the only thing that says which input activated
 * the control — and whether one did at all, since keyboard activation
 * synthesizes a click with no pointer behind it.
 *
 * State goes in with the record because a click reports that no better: a
 * browser that focuses a control on contact can open the very panel the tap
 * was meant to open, and reading "is it open" at click time then undoes it.
 * What the gesture started against is what it acts on.
 *
 * The record is spent by one click and dropped by everything else, because a
 * record that outlives its gesture is worse than none:
 *
 * - A scroll or an OS gesture takes the touch away — `pointercancel`, no click
 *   ever — and the finger would sit in the record until some later click.
 * - That later click is often `Enter` on a keyboard, which arrives with no
 *   pointerdown of its own and would inherit the abandoned finger. A keydown
 *   is the start of a keyboard activation and never part of a tap, so it drops
 *   the record too.
 *
 * Both ends have to be wired by the surface: `drop` on `onPointerCancel` and
 * on `onKeyDown`.
 */
export function useTapGesture<S>(): TapGesture<S> {
  const record = useRef<TapRecord<S> | null>(null);

  return useMemo(
    () => ({
      start: (event, state) => {
        record.current = { pointerType: event.pointerType, state };
      },
      take: () => {
        const spent = record.current;
        record.current = null;
        return spent;
      },
      drop: () => {
        record.current = null;
      },
    }),
    [],
  );
}

// Shared touch primitives. iOS and iPadOS run their own gestures on top of the
// page — the long-press selection callout and the selection it drags in with
// it — and they win: once the platform claims a touch it cancels ours
// mid-gesture, so a press-and-hold or a drag simply dies. Surfaces that own
// their gesture have to opt out.
//
// What the two classes below cover, precisely:
// - `-webkit-touch-callout: none` stops iOS's long-press callout. WebKit-only:
//   it is not a property other engines have, so it is inert everywhere else.
// - `user-select: none` stops the long-press selection on every engine,
//   Android included, and stops a drag from painting a selection under the
//   cursor. It is inherited, so it reaches every descendant — which is why the
//   two classes differ only in whether they apply it unconditionally.
// What neither covers:
// - Chrome for Android's long-press menu on a link or an image. No CSS
//   suppresses it; a gesture surface that wraps one needs its own
//   `onContextMenu` with `preventDefault()`.
// - The native drag of an `<img>` or `<a>` descendant. `-webkit-user-drag` is
//   not inherited and plain divs and buttons are not drag sources, so setting
//   it on the surface does nothing — the child itself needs `draggable={false}`.

/**
 * Classes for a surface that *is* the control: a thumb, a drum, a stage, a
 * handle, a hold button. Selection is suppressed on every input, because a
 * drag that highlights the control's own label is wrong on a mouse too.
 * Compose with `touch-none` when the surface also owns the scroll axis — leave
 * it off when the page must still scroll from there.
 */
export const TOUCH_GESTURE_CLASS = "select-none [-webkit-touch-callout:none]";

/**
 * The same opt-out for a gesture surface that wraps content the consumer owns:
 * a scroller, a context-menu trigger, a sheet header, a list row. Selection is
 * suppressed only where the platform runs its own press gestures — a coarse
 * pointer — so a mouse user can still select and copy that content. If the
 * gesture itself would paint a selection under the cursor, add `select-none`
 * for the duration of the gesture rather than reaching for
 * `TOUCH_GESTURE_CLASS`.
 *
 * `pointer: coarse` describes the *primary* pointer and nothing else, so a
 * hybrid machine reads it wrong in both directions: a tablet with a mouse
 * plugged in keeps touch as primary and loses mouse selection, and a laptop
 * with a touchscreen keeps the mouse as primary and leaves selection live
 * under a finger. No media query can answer per interaction — the query is
 * about the device, and the question is about the gesture in progress. The
 * default stays here because it is right on the machines that are one thing or
 * the other, and losing a selection is a nuisance; where the miss costs a
 * *gesture* instead, the surface pairs it with `holdSelection` on the press.
 */
export const TOUCH_GESTURE_CONTENT_CLASS =
  "[-webkit-touch-callout:none] pointer-coarse:select-none";

/**
 * Suppress selection on `element` for as long as a gesture is running on it,
 * whatever the primary pointer of the machine happens to be. Returns the
 * release. Inline, so it wins over the class above and is gone again the
 * moment the gesture ends.
 *
 * For the press gestures a native selection would otherwise steal — a
 * long-press that opens a menu. Elsewhere prefer the classes: a surface that
 * takes selection away for the whole session is a surface whose text nobody
 * can copy.
 */
export function holdSelection(element: HTMLElement) {
  element.style.setProperty("user-select", "none");
  element.style.setProperty("-webkit-user-select", "none");
  return () => {
    element.style.removeProperty("user-select");
    element.style.removeProperty("-webkit-user-select");
  };
}

/**
 * Pointer capture, best effort. WebKit throws `NotFoundError` when the pointer
 * is already gone by the time the handler runs — routine on iOS, where the
 * system can claim the touch first — and an uncaught throw takes the rest of
 * the handler, the gesture included, down with it. Touch pointers carry
 * implicit capture anyway, so losing it is never fatal.
 */
export function capturePointer(element: Element, pointerId: number) {
  try {
    element.setPointerCapture(pointerId);
  } catch {
    // Pointer is no longer active — implicit capture still applies on touch.
  }
}

/** Release a capture taken with `capturePointer`, ignoring a stale pointer. */
export function releasePointer(element: Element, pointerId: number) {
  try {
    if (element.hasPointerCapture(pointerId)) {
      element.releasePointerCapture(pointerId);
    }
  } catch {
    // Capture was already dropped by the browser.
  }
}

/**
 * Whether this event came from a pointer that is *hovering*: not a touch, and
 * not currently pressed. Which input the user is holding right now is not
 * something a device capability can answer — a touchscreen laptop hovers and
 * taps, and iPadOS reports a fine hovering pointer for a finger — so both
 * paths stay live and each handler branches on the event it was given.
 *
 * A pen resting on the glass is making contact, not hovering: `buttons` is the
 * tell, and it sends a pen tap down the same route a finger takes.
 *
 * This answers what an *enter* asks. A leave is the other half of a pair and
 * has to be read against the enter that started it — `useHoverGesture` in
 * `lib/hooks/use-hover-gesture` does that, and hover surfaces should use it
 * rather than asking this question twice.
 */
export const isHoveringPointer = (event: {
  pointerType: string;
  buttons: number;
}) => event.pointerType !== "touch" && event.buttons === 0;

"use client";
// beui.dev/components/motion/avatar-group

import { AnimatePresence, motion, useReducedMotion } from "motion/react";
import { type ComponentPropsWithRef, type PointerEvent, useState } from "react";
import { Tooltip, TooltipProvider } from "@/components/motion/tooltip";
import { EASE_OUT, SPRING_LAYOUT, SPRING_PRESS } from "@/lib/ease";
import { useHoverCapable } from "@/lib/hooks/use-hover-capable";
import { cn } from "@/lib/utils";

export interface AvatarGroupMember {
  id: string;
  name: string;
  /** Image URL. Without one, or if it fails to load, initials show. */
  src?: string;
}

const SIZES = {
  sm: { box: "size-7 text-[10px]", px: 28 },
  md: { box: "size-9 text-xs", px: 36 },
  lg: { box: "size-11 text-sm", px: 44 },
} as const;

type AvatarSize = keyof typeof SIZES;

function initials(name: string) {
  const parts = name.trim().split(/\s+/).filter(Boolean);
  const letters = parts.length > 1 ? parts[0][0] + parts[parts.length - 1][0] : (parts[0] ?? "?").slice(0, 2);
  return letters.toUpperCase();
}

export interface AvatarProps extends Omit<ComponentPropsWithRef<"span">, "children"> {
  name: string;
  src?: string;
  size?: AvatarSize;
}

/** One avatar: the image, or initials when there is no image or it fails. */
export function Avatar({ name, src, size = "md", className, ...props }: AvatarProps) {
  const [failedSrc, setFailedSrc] = useState<string>();
  const showImage = src && failedSrc !== src;
  return (
    <span
      {...props}
      className={cn(
        "relative inline-flex shrink-0 items-center justify-center overflow-hidden rounded-full bg-card font-medium text-muted-foreground ring-2 ring-background select-none",
        SIZES[size].box,
        className,
      )}
    >
      {showImage ? (
        // biome-ignore lint/performance/noImgElement: a portable component; avatars come from any host and fall back to initials on error
        <img
          src={src}
          alt={name}
          draggable={false}
          onError={() => setFailedSrc(src)}
          className="size-full object-cover"
        />
      ) : (
        <>
          <span aria-hidden="true">{initials(name)}</span>
          <span className="sr-only">{name}</span>
        </>
      )}
    </span>
  );
}

export interface AvatarGroupProps extends Omit<ComponentPropsWithRef<"div">, "children"> {
  members: AvatarGroupMember[];
  /** Avatars shown before the rest collapse into a +N count. */
  max?: number;
  size?: AvatarSize;
  /** Whether every member is shown. Pair with `onExpandedChange`. */
  expanded?: boolean;
  defaultExpanded?: boolean;
  onExpandedChange?: (expanded: boolean) => void;
  /** Accessible name for the list, such as "Project members". */
  label?: string;
}

/**
 * Overlapping avatars that fan apart on hover, lift the one under the pointer
 * with its name, and expand from a +N count to show everyone.
 */
export function AvatarGroup({
  members,
  max = 4,
  size = "md",
  expanded,
  defaultExpanded = false,
  onExpandedChange,
  label = "Members",
  className,
  ...props
}: AvatarGroupProps) {
  const reduce = useReducedMotion();
  const canHover = useHoverCapable();
  const [internalExpanded, setInternalExpanded] = useState(defaultExpanded);
  const isExpanded = expanded ?? internalExpanded;
  // Index of the avatar under a mouse pointer; the +N button counts as the
  // last slot.
  const [hovered, setHovered] = useState<number | null>(null);

  const limit = Math.max(1, max);
  const overflow = Math.max(0, members.length - limit);
  const visible = isExpanded ? members : members.slice(0, limit);
  const px = SIZES[size].px;
  // Avatars overlap by a third of their width. Hovering one parts the row
  // around it: everything before slides back, everything after slides on,
  // so the hovered avatar shows in full while the group stays in place.
  const overlap = Math.round(px / 3);
  const push = Math.round(overlap * 0.75);
  const parting = !reduce && canHover && hovered !== null;
  const offset = (index: number) =>
    !parting || index === hovered ? 0 : index < (hovered ?? 0) ? -push : push;
  const hoverHandlers = (index: number) => ({
    onPointerEnter: (event: PointerEvent) => {
      if (event.pointerType === "mouse") setHovered(index);
    },
  });

  const toggle = () => {
    const next = !isExpanded;
    if (expanded === undefined) setInternalExpanded(next);
    onExpandedChange?.(next);
  };

  return (
    <TooltipProvider skipDelay={400}>
      <div
        {...props}
        onPointerLeave={(event) => {
          props.onPointerLeave?.(event);
          setHovered(null);
        }}
        className={cn("inline-flex items-center", className)}
      >
        <ul aria-label={label} className="relative flex items-center">
          <AnimatePresence initial={false} mode="popLayout">
            {visible.map((member, index) => (
              <motion.li
                key={member.id}
                layout={reduce ? false : "position"}
                initial={{ opacity: 0, scale: reduce ? 1 : 0.6 }}
                animate={{ opacity: 1, scale: 1 }}
                exit={{
                  opacity: 0,
                  scale: reduce ? 1 : 0.6,
                  transition: { duration: 0.14, ease: EASE_OUT },
                }}
                transition={{ layout: SPRING_LAYOUT, scale: SPRING_LAYOUT, opacity: { duration: 0.18, ease: EASE_OUT } }}
                // Later avatars sit on top, except the hovered one.
                style={{
                  marginLeft: index === 0 ? 0 : -overlap,
                  zIndex: parting && hovered === index ? visible.length + 1 : index,
                  position: "relative",
                }}
              >
                <Tooltip content={member.name} side="top">
                  <motion.span
                    className="block rounded-full"
                    {...hoverHandlers(index)}
                    animate={{
                      x: offset(index),
                      y: parting && hovered === index ? -3 : 0,
                      scale: parting && hovered === index ? 1.06 : 1,
                    }}
                    transition={SPRING_LAYOUT}
                  >
                    <Avatar name={member.name} src={member.src} size={size} />
                  </motion.span>
                </Tooltip>
              </motion.li>
            ))}
            {overflow > 0 ? (
              <motion.li
                key="overflow"
                layout={reduce ? false : "position"}
                transition={{ layout: SPRING_LAYOUT }}
                style={{ marginLeft: -overlap, zIndex: visible.length, position: "relative" }}
              >
                <motion.span
                  className="block"
                  {...hoverHandlers(visible.length)}
                  animate={{ x: offset(visible.length) }}
                  transition={SPRING_LAYOUT}
                >
                  <motion.button
                    type="button"
                    aria-expanded={isExpanded}
                    aria-label={isExpanded ? "Show fewer members" : `Show ${overflow} more members`}
                    onClick={toggle}
                    whileTap={reduce ? undefined : { scale: 0.92 }}
                    transition={SPRING_PRESS}
                    className={cn(
                      "relative inline-flex shrink-0 items-center justify-center overflow-hidden rounded-full bg-foreground font-medium text-background tabular-nums ring-2 ring-background outline-none focus-visible:ring-ring",
                      SIZES[size].box,
                    )}
                  >
                    <AnimatePresence initial={false} mode="popLayout">
                      <motion.span
                        key={isExpanded ? "less" : "more"}
                        aria-hidden="true"
                        initial={{ opacity: 0, y: reduce ? 0 : isExpanded ? 8 : -8 }}
                        animate={{ opacity: 1, y: 0 }}
                        exit={{ opacity: 0, y: reduce ? 0 : isExpanded ? -8 : 8 }}
                        transition={{ duration: 0.16, ease: EASE_OUT }}
                      >
                        {isExpanded ? "−" : `+${overflow}`}
                      </motion.span>
                    </AnimatePresence>
                  </motion.button>
                </motion.span>
              </motion.li>
            ) : null}
          </AnimatePresence>
        </ul>
      </div>
    </TooltipProvider>
  );
}

"use client";

import { AnimatePresence } from "motion/react";
import {
  type ComponentProps,
  type PointerEvent as ReactPointerEvent,
  cloneElement,
  createContext,
  isValidElement,
  type ReactElement,
  type ReactNode,
  type Ref,
  type RefObject,
  useCallback,
  useContext,
  useEffect,
  useId,
  useLayoutEffect,
  useMemo,
  useRef,
  useState,
} from "react";
import { createPortal } from "react-dom";
import { TooltipSurface } from "@/components/motion/tooltip-surface";
import { useDismiss } from "@/lib/hooks/use-dismiss";
import { useHoverGesture } from "@/lib/hooks/use-hover-gesture";
import { useTapGesture } from "@/lib/hooks/use-tap-gesture";
import { cn } from "@/lib/utils";
import { focusFromKeyboard, graceArea, inBox, inPolygon, watchModality } from "./tooltip/grace";
import { TooltipArrow, TooltipPositioner } from "./tooltip/positioner";
import {
  type TooltipAlign,
  type TooltipAnchor,
  type TooltipPoint,
  type TooltipSide,
  useTooltipPointer,
} from "./tooltip/use-position";

export type { TooltipAlign, TooltipSide };

/* -------------------------------------------------------------------------- */
/* Provider                                                                   */
/* -------------------------------------------------------------------------- */

interface TooltipTiming {
  /** Delay before a hover opens a tooltip (ms). */
  delay: number;
  /** Delay before a tooltip closes once the pointer has left it (ms). */
  closeDelay: number;
  /** After one tooltip closes, others open instantly for this long (ms). */
  skipDelay: number;
}

const TimingContext = createContext<TooltipTiming>({ delay: 120, closeDelay: 0, skipDelay: 300 });

export interface TooltipProviderProps extends Partial<TooltipTiming> {
  children: ReactNode;
}

/** Shared timing for every tooltip inside it. Optional: tooltips work without one. */
export function TooltipProvider({ children, ...timing }: TooltipProviderProps) {
  const parent = useContext(TimingContext);
  const { delay = parent.delay, closeDelay = parent.closeDelay, skipDelay = parent.skipDelay } =
    timing;
  const value = useMemo(() => ({ delay, closeDelay, skipDelay }), [delay, closeDelay, skipDelay]);
  return <TimingContext.Provider value={value}>{children}</TimingContext.Provider>;
}

/* -------------------------------------------------------------------------- */
/* Root                                                                       */
/* -------------------------------------------------------------------------- */

// Moving along a toolbar should feel instant after the first label, and only
// one label may show at a time: a keyboard-focused control and a hovered one
// would otherwise both claim the screen.
let lastClosedAt = 0;
let current: { close: () => void } | null = null;

function isEmpty(content: ReactNode) {
  return content == null || content === false || content === "";
}

interface TooltipContextValue {
  open: boolean;
  contentId: string;
  labelId: string;
  asLabel: boolean;
  empty: boolean;
  followCursor: boolean;
  anchor: TooltipAnchor | null;
  /** True when a TooltipTrigger owns the anchor; false for an external `anchorRef`. */
  triggered: boolean;
  floatingRef: RefObject<HTMLSpanElement | null>;
  pointer: ReturnType<typeof useTooltipPointer>;
  setTrigger: (element: TooltipAnchor | null) => void;
  setEmpty: (empty: boolean) => void;
  close: () => void;
  onContentEnter: () => void;
  onContentLeave: (event: ReactPointerEvent) => void;
}

const TooltipContext = createContext<TooltipContextValue | null>(null);

function useTooltipContext(part: string) {
  const context = useContext(TooltipContext);
  if (!context) throw new Error(`${part} must be used inside <Tooltip>`);
  return context;
}

export interface TooltipRootProps {
  children?: ReactNode;
  open?: boolean;
  defaultOpen?: boolean;
  onOpenChange?: (open: boolean) => void;
  /** Delay before showing on hover (ms). Keyboard focus shows immediately. */
  delay?: number;
  /** Delay before hiding once the pointer has left (ms). */
  closeDelay?: number;
  /** Never show, e.g. while the label it carries is already visible. */
  disabled?: boolean;
  /**
   * Use the tooltip as the trigger's accessible name rather than its
   * description. For icon-only controls whose only label is the tooltip.
   */
  asLabel?: boolean;
  /** Follow real pointer coordinates; keyboard focus still uses the anchor. */
  followCursor?: boolean;
  /** Existing anchor for controlled integrations such as chart cells. */
  anchorRef?: RefObject<TooltipAnchor | null>;
  /** Id of the tooltip surface, for anchors that reference it themselves. */
  id?: string;
}

function TooltipRoot({
  children,
  open: controlledOpen,
  defaultOpen = false,
  onOpenChange,
  delay: delayProp,
  closeDelay: closeDelayProp,
  disabled = false,
  asLabel = false,
  followCursor = false,
  anchorRef,
  id,
  initialEmpty = false,
}: TooltipRootProps & { initialEmpty?: boolean }) {
  const timing = useContext(TimingContext);
  const delay = delayProp ?? timing.delay;
  const closeDelay = closeDelayProp ?? timing.closeDelay;
  const [uncontrolledOpen, setUncontrolledOpen] = useState(defaultOpen);
  const open = controlledOpen ?? uncontrolledOpen;
  const [empty, setEmpty] = useState(initialEmpty);
  const [trigger, setTrigger] = useState<TooltipAnchor | null>(null);
  const [external, setExternal] = useState<TooltipAnchor | null>(null);
  const anchor = anchorRef ? external : trigger;
  const generatedId = useId();
  const contentId = id ?? `${generatedId}-content`;
  const labelId = `${generatedId}-label`;
  const floatingRef = useRef<HTMLSpanElement | null>(null);
  const anchorObject = useRef<TooltipAnchor | null>(null);
  const pointer = useTooltipPointer(anchor, followCursor);

  // An external ref can attach after this component renders; read it once it has.
  useLayoutEffect(() => {
    if (!anchorRef) return;
    const element = anchorRef.current ?? null;
    if (element !== external) setExternal(element);
  });

  // Everything the event listeners read, current without re-binding them.
  const latest = useRef({ open, delay, closeDelay, disabled, empty, onOpenChange, controlled: false });
  useLayoutEffect(() => {
    anchorObject.current = anchor;
    latest.current = {
      open,
      delay,
      closeDelay,
      disabled,
      empty,
      onOpenChange,
      controlled: controlledOpen !== undefined,
    };
  });

  const openTimer = useRef<ReturnType<typeof setTimeout> | null>(null);
  const closeTimer = useRef<ReturnType<typeof setTimeout> | null>(null);
  const grace = useRef<(() => void) | null>(null);
  const self = useRef<{ close: () => void }>({ close: () => {} });

  const clearTimers = useCallback(() => {
    if (openTimer.current) clearTimeout(openTimer.current);
    if (closeTimer.current) clearTimeout(closeTimer.current);
    openTimer.current = null;
    closeTimer.current = null;
  }, []);

  const stopGrace = useCallback(() => {
    grace.current?.();
    grace.current = null;
  }, []);

  // Only a real change reaches the consumer: a pointer leaving a closed
  // tooltip is not news.
  const commit = useCallback((next: boolean) => {
    if (latest.current.open === next) return;
    if (!latest.current.controlled) setUncontrolledOpen(next);
    latest.current.onOpenChange?.(next);
  }, []);

  const openNow = useCallback(() => {
    clearTimers();
    stopGrace();
    if (latest.current.disabled || latest.current.empty) return;
    if (current && current !== self.current) current.close();
    current = self.current;
    commit(true);
  }, [clearTimers, stopGrace, commit]);

  const close = useCallback(() => {
    clearTimers();
    stopGrace();
    if (latest.current.open) lastClosedAt = Date.now();
    if (current === self.current) current = null;
    commit(false);
  }, [clearTimers, stopGrace, commit]);
  useLayoutEffect(() => {
    self.current.close = close;
  }, [close]);

  const requestOpen = useCallback(() => {
    clearTimers();
    if (latest.current.open || latest.current.disabled || latest.current.empty) return;
    const warm = Date.now() - lastClosedAt < timing.skipDelay;
    if (warm || latest.current.delay <= 0) openNow();
    else openTimer.current = setTimeout(openNow, latest.current.delay);
  }, [clearTimers, openNow, timing.skipDelay]);

  const requestClose = useCallback(() => {
    clearTimers();
    if (latest.current.closeDelay > 0) {
      closeTimer.current = setTimeout(close, latest.current.closeDelay);
    } else close();
  }, [clearTimers, close]);

  // Hold the label open while the pointer crosses from one box toward the other.
  const startGrace = useCallback(
    (exit: TooltipPoint, from: Element, to: Element | null) => {
      stopGrace();
      if (!to) return requestClose();
      const target = to.getBoundingClientRect();
      const origin = from.getBoundingClientRect();
      const corridor = graceArea(exit, target);
      const onMove = (event: PointerEvent) => {
        const point = { x: event.clientX, y: event.clientY };
        if (inBox(point, target) || inBox(point, origin)) return;
        if (!inPolygon(point, corridor)) requestClose();
      };
      document.addEventListener("pointermove", onMove);
      grace.current = () => document.removeEventListener("pointermove", onMove);
    },
    [stopGrace, requestClose],
  );

  const hover = useHoverGesture();
  const tap = useTapGesture<boolean>();

  // Listeners go on the trigger itself rather than on cloned props, so a
  // component that owns its own handlers keeps them, and no wrapper element
  // sits between the control and its layout.
  useEffect(() => {
    if (anchorRef || !trigger) return;
    watchModality();
    // A mouse press dismisses the label and keeps it away until the pointer
    // leaves; hovering a control you just clicked should not bring it back.
    let suppressed = false;
    // Focus that came from the keyboard holds the label open on its own.
    let keyboardFocus = false;

    const onEnter = (event: PointerEvent) => {
      if (!hover.enter(event)) return;
      stopGrace();
      if (closeTimer.current) clearTimeout(closeTimer.current);
      if (!suppressed) requestOpen();
    };
    const onLeave = (event: PointerEvent) => {
      if (!hover.leave(event)) return;
      suppressed = false;
      if (keyboardFocus) return;
      if (openTimer.current) {
        clearTimers();
        return;
      }
      if (latest.current.open && !followCursor) {
        startGrace({ x: event.clientX, y: event.clientY }, trigger, floatingRef.current);
      } else requestClose();
    };
    const onDown = (event: PointerEvent) => {
      tap.start(event, latest.current.open);
      if (event.pointerType === "mouse") {
        suppressed = true;
        close();
      }
    };
    // A finger never hovers, and Safari does not focus a button on tap either,
    // so the label is only reachable if the tap itself toggles it. The click
    // carries no pointerType; the pointerdown before it says whether it was a
    // tap, and keyboard activation has none at all.
    const onClick = () => {
      const gesture = tap.take();
      if (!gesture || gesture.pointerType === "mouse") return;
      if (gesture.state) close();
      else openNow();
    };
    const onKey = () => tap.drop();
    const onFocusIn = () => {
      if (!focusFromKeyboard()) return;
      keyboardFocus = true;
      openNow();
    };
    const onFocusOut = (event: FocusEvent) => {
      if (trigger.contains(event.relatedTarget as Node | null)) return;
      keyboardFocus = false;
      close();
    };

    // Both element kinds dispatch the same events; one type keeps the listeners typed.
    const el = trigger as HTMLElement;
    el.addEventListener("pointerenter", onEnter);
    el.addEventListener("pointerleave", onLeave);
    el.addEventListener("pointerdown", onDown);
    el.addEventListener("pointercancel", tap.drop);
    el.addEventListener("click", onClick);
    el.addEventListener("keydown", onKey);
    el.addEventListener("focusin", onFocusIn);
    el.addEventListener("focusout", onFocusOut);
    return () => {
      el.removeEventListener("pointerenter", onEnter);
      el.removeEventListener("pointerleave", onLeave);
      el.removeEventListener("pointerdown", onDown);
      el.removeEventListener("pointercancel", tap.drop);
      el.removeEventListener("click", onClick);
      el.removeEventListener("keydown", onKey);
      el.removeEventListener("focusin", onFocusIn);
      el.removeEventListener("focusout", onFocusOut);
    };
  }, [
    anchorRef,
    trigger,
    followCursor,
    hover,
    tap,
    requestOpen,
    requestClose,
    openNow,
    close,
    clearTimers,
    stopGrace,
    startGrace,
  ]);

  // While open, a trigger that turns disabled loses focus without a blur event,
  // and a window that loses focus never reports the pointer leaving.
  useEffect(() => {
    if (!open || anchorRef || !trigger) return;
    const observer = new MutationObserver(() => {
      if (trigger.matches(":disabled, [aria-disabled='true']")) close();
    });
    observer.observe(trigger, { attributes: true, attributeFilter: ["disabled", "aria-disabled"] });
    window.addEventListener("blur", close);
    return () => {
      observer.disconnect();
      window.removeEventListener("blur", close);
    };
  }, [open, anchorRef, trigger, close]);

  // A chart drives its own open state and swaps content as it goes; only a
  // trigger-owned label closes itself for having nothing to say.
  useEffect(() => {
    if (disabled || (empty && !anchorRef)) close();
  }, [disabled, empty, anchorRef, close]);

  useEffect(
    () => () => {
      clearTimers();
      stopGrace();
      if (current === self.current) current = null;
    },
    [clearTimers, stopGrace],
  );

  const insideTooltip = useCallback(
    (target: Element) => Boolean(floatingRef.current?.contains(target)),
    [],
  );
  // ...and closed by the next tap that lands somewhere else, or Escape. The
  // label covers nothing interactive, so that tap passes through to what it hit.
  useDismiss(open, close, anchorObject, { ignore: insideTooltip });

  const onContentEnter = useCallback(() => {
    stopGrace();
    clearTimers();
  }, [stopGrace, clearTimers]);

  const onContentLeave = useCallback(
    (event: ReactPointerEvent) => {
      const floating = floatingRef.current;
      if (!floating) return;
      if (anchorRef) {
        // Bridge the small gap back onto a chart; it reopens on its own terms.
        clearTimers();
        closeTimer.current = setTimeout(close, 100);
        return;
      }
      startGrace({ x: event.clientX, y: event.clientY }, floating, anchorObject.current);
    },
    [anchorRef, clearTimers, close, startGrace],
  );

  const value = useMemo<TooltipContextValue>(
    () => ({
      open,
      contentId,
      labelId,
      asLabel,
      empty,
      followCursor,
      anchor,
      triggered: !anchorRef,
      floatingRef,
      pointer,
      setTrigger,
      setEmpty,
      close,
      onContentEnter,
      onContentLeave,
    }),
    [
      open,
      contentId,
      labelId,
      asLabel,
      empty,
      followCursor,
      anchor,
      anchorRef,
      pointer,
      close,
      onContentEnter,
      onContentLeave,
    ],
  );

  return <TooltipContext.Provider value={value}>{children}</TooltipContext.Provider>;
}

/* -------------------------------------------------------------------------- */
/* Trigger                                                                    */
/* -------------------------------------------------------------------------- */

function mergeIds(...ids: unknown[]) {
  return ids.filter((value) => typeof value === "string" && value).join(" ") || undefined;
}

function assignRef<T>(ref: Ref<T> | undefined, value: T | null) {
  if (typeof ref === "function") ref(value);
  else if (ref) (ref as { current: T | null }).current = value;
}

export interface TooltipTriggerProps extends ComponentProps<"button"> {
  /** Use the single child element as the trigger instead of rendering a button. */
  asChild?: boolean;
}

export function TooltipTrigger({ asChild = false, children, ref, ...props }: TooltipTriggerProps) {
  const { open, contentId, labelId, asLabel, empty, setTrigger } =
    useTooltipContext("TooltipTrigger");
  const child = asChild && isValidElement(children) ? children : null;
  const childProps = (child?.props ?? props) as Record<string, unknown>;
  const childRef = child ? (childProps.ref as Ref<TooltipAnchor> | undefined) : undefined;
  const attached = useRef<TooltipAnchor | null>(null);

  const setRef = useCallback(
    (element: TooltipAnchor | null) => {
      attached.current = element;
      setTrigger(element);
      assignRef(childRef ?? (ref as Ref<TooltipAnchor> | undefined), element);
    },
    [setTrigger, childRef, ref],
  );

  useEffect(() => {
    if (process.env.NODE_ENV !== "production" && child && !attached.current) {
      console.warn(
        "TooltipTrigger: the child did not attach a ref, so the tooltip has nothing to listen to. Render a DOM element or a component that passes `ref` through.",
      );
    }
  }, [child]);

  const aria = asLabel
    ? {
        "aria-labelledby": empty
          ? (childProps["aria-labelledby"] as string | undefined)
          : labelId,
      }
    : {
        "aria-describedby": mergeIds(
          childProps["aria-describedby"],
          open && !empty ? contentId : undefined,
        ),
      };

  if (asChild) {
    if (!child) return children;
    return cloneElement(child as ReactElement<Record<string, unknown>>, { ref: setRef, ...aria });
  }

  return (
    <button
      type="button"
      data-state={open ? "open" : "closed"}
      {...props}
      ref={setRef as Ref<HTMLButtonElement>}
      {...aria}
    >
      {children}
    </button>
  );
}

/* -------------------------------------------------------------------------- */
/* Content                                                                    */
/* -------------------------------------------------------------------------- */

export interface TooltipContentProps {
  children?: ReactNode;
  side?: TooltipSide;
  align?: TooltipAlign;
  /** Gap between anchor and tooltip (px). */
  sideOffset?: number;
  /** Draw an arrow pointing at the anchor. */
  arrow?: boolean;
  /** Point within the anchor, as fractions of its rendered width and height. */
  anchorPoint?: TooltipPoint;
  className?: string;
}

export function TooltipContent({
  children,
  side = "top",
  align = "center",
  sideOffset,
  arrow = false,
  anchorPoint,
  className,
}: TooltipContentProps) {
  const {
    open,
    contentId,
    labelId,
    asLabel,
    followCursor,
    anchor,
    floatingRef,
    pointer,
    setEmpty,
    close,
    onContentEnter,
    onContentLeave,
  } = useTooltipContext("TooltipContent");
  const empty = isEmpty(children);
  const arrowRef = useRef<SVGSVGElement | null>(null);

  useLayoutEffect(() => {
    setEmpty(empty);
  }, [empty, setEmpty]);

  if (typeof document === "undefined") return null;

  return createPortal(
    <>
      {/* The name has to exist while the label is closed, so it lives apart from the surface. */}
      {asLabel && !empty ? (
        <span id={labelId} hidden>
          {children}
        </span>
      ) : null}
      <AnimatePresence>
        {open && !empty ? (
          <TooltipPositioner
            key="tooltip"
            anchor={anchor}
            floatingRef={floatingRef}
            arrowRef={arrow ? arrowRef : undefined}
            anchorPoint={anchorPoint}
            followCursor={followCursor}
            side={side}
            align={align}
            sideOffset={sideOffset}
            onDismiss={close}
            pointer={pointer}
          >
            {(positioned, isPresent, placedSide) => (
              <TooltipSurface
                id={asLabel ? undefined : contentId}
                aria-hidden={asLabel || undefined}
                ready={positioned}
                onPointerEnter={onContentEnter}
                onPointerLeave={onContentLeave}
                style={{ pointerEvents: isPresent && !followCursor ? "auto" : "none" }}
                className={cn(
                  "max-w-[min(20rem,calc(100vw-16px))] whitespace-normal break-words",
                  arrow && "relative",
                  className,
                )}
              >
                {children}
                {arrow ? <TooltipArrow ref={arrowRef} side={placedSide} /> : null}
              </TooltipSurface>
            )}
          </TooltipPositioner>
        ) : null}
      </AnimatePresence>
    </>,
    document.body,
  );
}

/* -------------------------------------------------------------------------- */
/* Tooltip (root, or one-line shorthand when given `content`)                 */
/* -------------------------------------------------------------------------- */

export interface TooltipProps
  extends TooltipRootProps,
    Omit<TooltipContentProps, "children" | "className"> {
  /**
   * Shorthand: the tooltip's content. With it, `children` is the trigger
   * element; without it, compose `TooltipTrigger` and `TooltipContent`.
   */
  content?: ReactNode;
  /** Shorthand only: classes for the tooltip surface. */
  className?: string;
}

export function Tooltip(props: TooltipProps) {
  if (!("content" in props)) return <TooltipRoot {...props} />;
  const {
    content,
    children,
    side,
    align,
    sideOffset,
    arrow,
    anchorPoint,
    className,
    ...root
  } = props;
  if (!root.anchorRef && !isValidElement(children)) return children ?? null;
  return (
    <TooltipRoot {...root} initialEmpty={isEmpty(content)}>
      {isValidElement(children) ? <TooltipTrigger asChild>{children}</TooltipTrigger> : null}
      <TooltipContent
        side={side}
        align={align}
        sideOffset={sideOffset}
        arrow={arrow}
        anchorPoint={anchorPoint}
        className={className}
      >
        {content}
      </TooltipContent>
    </TooltipRoot>
  );
}

type Point = { x: number; y: number };
type Box = { left: number; top: number; right: number; bottom: number };

/**
 * The corridor a pointer may cross between the trigger and the open tooltip
 * without closing it: the convex hull of where it left and the box it is
 * heading for. A fixed timeout either cuts a slow diagonal move short or keeps
 * the label alive after the pointer has plainly gone elsewhere; this follows
 * the path itself.
 */
export function graceArea(exit: Point, target: Box): Point[] {
  // A few pixels either side of the exit point give the corridor some width at
  // its narrow end, so a hand that drifts sideways while it moves stays inside.
  const pad = 5;
  return hull([
    { x: exit.x - pad, y: exit.y - pad },
    { x: exit.x + pad, y: exit.y - pad },
    { x: exit.x - pad, y: exit.y + pad },
    { x: exit.x + pad, y: exit.y + pad },
    { x: target.left, y: target.top },
    { x: target.right, y: target.top },
    { x: target.right, y: target.bottom },
    { x: target.left, y: target.bottom },
  ]);
}

export function inBox(point: Point, box: Box) {
  return (
    point.x >= box.left && point.x <= box.right && point.y >= box.top && point.y <= box.bottom
  );
}

export function inPolygon(point: Point, polygon: Point[]) {
  let inside = false;
  for (let i = 0, j = polygon.length - 1; i < polygon.length; j = i++) {
    const a = polygon[i];
    const b = polygon[j];
    if (
      a.y > point.y !== b.y > point.y &&
      point.x < ((b.x - a.x) * (point.y - a.y)) / (b.y - a.y) + a.x
    ) {
      inside = !inside;
    }
  }
  return inside;
}

// Monotone chain; the corridor is always convex, so a hull is all it needs.
function hull(points: Point[]) {
  const sorted = [...points].sort((a, b) => a.x - b.x || a.y - b.y);
  const cross = (o: Point, a: Point, b: Point) =>
    (a.x - o.x) * (b.y - o.y) - (a.y - o.y) * (b.x - o.x);
  const lower: Point[] = [];
  for (const p of sorted) {
    while (lower.length >= 2 && cross(lower[lower.length - 2], lower[lower.length - 1], p) <= 0) {
      lower.pop();
    }
    lower.push(p);
  }
  const upper: Point[] = [];
  for (let i = sorted.length - 1; i >= 0; i--) {
    const p = sorted[i];
    while (upper.length >= 2 && cross(upper[upper.length - 2], upper[upper.length - 1], p) <= 0) {
      upper.pop();
    }
    upper.push(p);
  }
  lower.pop();
  upper.pop();
  return lower.concat(upper);
}

/**
 * How the user last reached for the page. A focus that a mouse press caused is
 * not a request to read the label: the pointer is already on the control and
 * hovering showed it. A focus that followed a key — Tab, or a roving arrow key
 * moving focus in script — is the only way a keyboard user sees it at all.
 */
let modality: "keyboard" | "pointer" = "keyboard";
let listening = false;

export function watchModality() {
  if (listening || typeof window === "undefined") return;
  listening = true;
  window.addEventListener("keydown", () => (modality = "keyboard"), true);
  window.addEventListener("pointerdown", () => (modality = "pointer"), true);
}

export function focusFromKeyboard() {
  return modality === "keyboard";
}