Tooltip

"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;
      },
    }),
    [],
  );
}

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

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

// 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;

// 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/tooltip

import { AnimatePresence } from "motion/react";
import {
  cloneElement,
  isValidElement,
  type PointerEvent,
  type ReactElement,
  type ReactNode,
  type RefObject,
  useCallback,
  useEffect,
  useId,
  useLayoutEffect,
  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";

type Side = "top" | "right" | "bottom" | "left";

export interface TooltipProps {
  content: ReactNode;
  children?: ReactElement;
  /** Existing trigger for controlled integrations such as chart cells. */
  anchorRef?: RefObject<HTMLElement | SVGElement | null>;
  /** Point within the anchor, as fractions of its rendered width and height. */
  anchorPoint?: { x: number; y: number };
  open?: boolean;
  onOpenChange?: (open: boolean) => void;
  id?: string;
  side?: Side;
  /** Delay before showing (ms). Default 120. */
  delay?: number;
  className?: string;
  /** Classes for the outer wrapper span. Use to fix baseline / fill parent. */
  wrapperClassName?: string;
}

// Gap between trigger and tooltip, in px.
const GAP = 8;

// Centering transform for the fixed-positioned anchor point, per side.
const anchorTransform: Record<Side, string> = {
  top: "translate(-50%, -100%)",
  bottom: "translate(-50%, 0)",
  left: "translate(-100%, -50%)",
  right: "translate(0, -50%)",
};

const transformOrigin: Record<Side, string> = {
  top: "center bottom",
  bottom: "center top",
  left: "right center",
  right: "left center",
};

// Once any tooltip has just closed, neighbouring tooltips open without the
// initial delay — moving along a toolbar feels instant after the first one.
const WARM_WINDOW_MS = 300;
let lastHiddenAt = 0;

export function Tooltip({
  content,
  children,
  side = "top",
  delay = 120,
  className,
  wrapperClassName,
  anchorRef: externalAnchorRef,
  anchorPoint,
  open: controlledOpen,
  onOpenChange,
  id: providedId,
}: TooltipProps) {
  const [internalOpen, setInternalOpen] = useState(false);
  const open = controlledOpen ?? internalOpen;
  const setOpen = useCallback(
    (next: boolean) => {
      if (controlledOpen === undefined) setInternalOpen(next);
      onOpenChange?.(next);
    },
    [controlledOpen, onOpenChange],
  );
  const [coords, setCoords] = useState<{ top: number; left: number } | null>(null);
  const generatedId = useId();
  const id = providedId ?? generatedId;
  const timer = useRef<ReturnType<typeof setTimeout> | null>(null);
  const wrapperRef = useRef<HTMLSpanElement>(null);
  const anchorRef = externalAnchorRef ?? wrapperRef;
  const hover = useHoverGesture();
  const surfaceRef = useRef<HTMLSpanElement>(null);

  // Anchor point in viewport coords, on the edge of the trigger facing `side`.
  // Position:fixed means these viewport coords place the tooltip directly, so
  // it escapes every ancestor's stacking context and overflow.
  const place = useCallback(() => {
    const el = anchorRef.current;
    if (!el) return;
    const r = el.getBoundingClientRect();
    const cx = r.left + r.width * (anchorPoint?.x ?? 0.5);
    const cy = r.top + r.height * (anchorPoint?.y ?? 0.5);
    const point: Record<Side, { top: number; left: number }> = {
      top: { top: (anchorPoint ? cy : r.top) - GAP, left: cx },
      bottom: { top: (anchorPoint ? cy : r.bottom) + GAP, left: cx },
      left: { top: cy, left: (anchorPoint ? cx : r.left) - GAP },
      right: { top: cy, left: (anchorPoint ? cx : r.right) + GAP },
    };
    const next = point[side];
    const width = surfaceRef.current?.offsetWidth ?? 0;
    const height = surfaceRef.current?.offsetHeight ?? 0;
    const dx = side === "left" ? width : side === "right" ? 0 : width / 2;
    const dy = side === "top" ? height : side === "bottom" ? 0 : height / 2;
    next.left = Math.max(GAP + dx, Math.min(next.left, window.innerWidth - GAP - width + dx));
    next.top = Math.max(GAP + dy, Math.min(next.top, window.innerHeight - GAP - height + dy));
    setCoords(previous => previous?.top === next.top && previous.left === next.left ? previous : next);
  }, [side, anchorRef, anchorPoint]);

  const positioned = coords !== null;
  useLayoutEffect(() => {
    if (!open) return;
    place();
    const observer = new ResizeObserver(place);
    if (anchorRef.current) observer.observe(anchorRef.current);
    if (positioned && surfaceRef.current) observer.observe(surfaceRef.current);
    return () => observer.disconnect();
  }, [open, place, anchorRef, positioned]);

  const show = useCallback(() => {
    if (timer.current) clearTimeout(timer.current);
    const warm = Date.now() - lastHiddenAt < WARM_WINDOW_MS;
    timer.current = setTimeout(
      () => {
        place();
        setOpen(true);
      },
      warm ? 0 : delay,
    );
  }, [delay, place, setOpen]);

  const hide = useCallback(() => {
    if (timer.current) {
      clearTimeout(timer.current);
      timer.current = null;
    }
    if (open) lastHiddenAt = Date.now();
    setOpen(false);
  }, [open, setOpen]);

  // A finger never hovers, and Safari does not focus a button on tap either, so
  // the label is only reachable if the tap itself opens the tooltip. A click
  // carries no pointerType, so the pointerdown that preceded it is what says
  // whether this was a tap; keyboard activation arrives with no pointerdown at
  // all, and focus has already shown the label there.
  const tap = useTapGesture<boolean>();

  const toggleOnTap = useCallback(() => {
    const gesture = tap.take();
    if (!gesture || gesture.pointerType === "mouse") return;
    if (gesture.state) {
      hide();
      return;
    }
    if (timer.current) clearTimeout(timer.current);
    place();
    setOpen(true);
  }, [hide, place, tap, setOpen]);

  // ...and closed again by the next tap that lands somewhere else. The label
  // covers nothing interactive, so that tap passes through to what it hit.
  useDismiss(open, hide, anchorRef);

  // Keep the tooltip pinned to the trigger while it's open and the page scrolls
  // or resizes (fixed coords are viewport-relative).
  useEffect(() => {
    if (!open) return;
    const onMove = () => place();
    window.addEventListener("scroll", onMove, true);
    window.addEventListener("resize", onMove);
    return () => {
      window.removeEventListener("scroll", onMove, true);
      window.removeEventListener("resize", onMove);
    };
  }, [open, place]);

  useEffect(
    () => () => {
      if (timer.current) clearTimeout(timer.current);
    },
    [],
  );

  if (!externalAnchorRef && !isValidElement(children)) return children;

  // The label describes the trigger, so it has to name the trigger itself.
  // Everything else the tooltip needs is read off the anchor below instead of
  // cloned on: a handler written onto the child is the child's handler as far
  // as that child can tell, and a component that owns its activation —
  // hard-wiring onClick and spreading the rest of its props over it, as
  // ThemeToggle does — then runs the tooltip's instead of its own. Composing
  // with `props.onClick` cannot save it either, because a component element's
  // props hold nothing the component does internally.
  const trigger = isValidElement(children)
    ? cloneElement(children as ReactElement<Record<string, unknown>>, {
        "aria-describedby": id,
      })
    : null;

  return (
    <>
      {!externalAnchorRef ? (
        // biome-ignore lint/a11y/noStaticElementInteractions: This wrapper observes bubbling trigger events without replacing the control's handlers.
        <span
          ref={wrapperRef}
          className={cn("relative inline-flex align-middle", wrapperClassName)}
          // Pointer events, not the mouse pair: a tap fires compatibility
          // mouseenter/mouseleave that carry no pointerType, which raced the tap
          // path into opening and closing the same label.
          onPointerEnter={(event: PointerEvent) => {
            if (hover.enter(event)) show();
          }}
          onPointerLeave={(event: PointerEvent) => {
            if (hover.leave(event)) hide();
          }}
          onFocus={show}
          onBlur={hide}
          onPointerDown={(event: PointerEvent) => tap.start(event, open)}
          // A gesture the platform took away sends no click, and a key press
          // starts an activation that never had a pointer behind it. Either way
          // the record has to go, or the next click reads a finger that has long
          // since lifted.
          onPointerCancel={tap.drop}
          onKeyDown={tap.drop}
          onClick={toggleOnTap}
        >
          {trigger}
        </span>
      ) : null}
      {typeof document !== "undefined"
        ? createPortal(
            <AnimatePresence>
              {open && coords ? (
                <span
                  className="pointer-events-none fixed z-[9999]"
                  style={{
                    top: coords.top,
                    left: coords.left,
                    transform: anchorTransform[side],
                  }}
                >
                  <TooltipSurface
                    ref={surfaceRef}
                    id={id}
                    side={side}
                    style={{ transformOrigin: transformOrigin[side], maxWidth: "calc(100vw - 16px)", whiteSpace: "normal" }}
                    className={className}
                  >
                    {content}
                  </TooltipSurface>
                </span>
              ) : null}
            </AnimatePresence>,
            document.body,
          )
        : null}
    </>
  );
}

"use client";

import { motion, useReducedMotion, type Variants } from "motion/react";
import { useMemo, type ComponentProps, type ReactNode, type Ref } from "react";
import { EASE_OUT } from "@/lib/ease";
import { cn } from "@/lib/utils";

type Side = "top" | "right" | "bottom" | "left";

// Offset is in the direction *away* from the trigger — content originates near
// the trigger and rises into resting position.
const offsetFrom: Record<Side, { x?: number; y?: number }> = {
  top: { y: 8 },
  bottom: { y: -8 },
  left: { x: 8 },
  right: { x: -8 },
};

// Small tooltip surfaces need the lighter spawn used by the original Tooltip.
const TOOLTIP_SPRING = { type: "spring", stiffness: 380, damping: 30, mass: 0.7 } as const;

function buildVariants(side: Side): Variants {
  const o = offsetFrom[side];
  return {
    initial: {
      opacity: 0,
      scale: 0.9,
      filter: "blur(5px)",
      x: o.x ?? 0,
      y: o.y ?? 0,
    },
    animate: {
      opacity: 1,
      scale: 1,
      filter: "blur(0px)",
      x: 0,
      y: 0,
      transition: {
        ...TOOLTIP_SPRING,
        opacity: { duration: 0.14, ease: EASE_OUT },
        filter: { duration: 0.18, ease: EASE_OUT },
      },
    },
    exit: {
      opacity: 0,
      scale: 0.94,
      filter: "blur(3px)",
      x: (o.x ?? 0) * 0.6,
      y: (o.y ?? 0) * 0.6,
      transition: { duration: 0.12, ease: EASE_OUT },
    },
  };
}

const REDUCED_VARIANTS: Variants = {
  initial: { opacity: 0 },
  animate: { opacity: 1, transition: { duration: 0.14, ease: EASE_OUT } },
  exit: { opacity: 0, transition: { duration: 0.1, ease: EASE_OUT } },
};

/** The shared visual surface for trigger tooltips and chart readouts. Positioning belongs to the caller. */
export function TooltipSurface({
  children,
  side = "top",
  className,
  ref,
  ...props
}: Omit<ComponentProps<typeof motion.span>, "children"> & {
  children?: ReactNode;
  side?: Side;
  ref?: Ref<HTMLSpanElement>;
}) {
  const reduce = useReducedMotion();
  const variants = useMemo(() => reduce ? REDUCED_VARIANTS : buildVariants(side), [reduce, side]);
  return (
    <motion.span
      ref={ref}
      role="tooltip"
      variants={variants}
      initial="initial"
      animate="animate"
      exit="exit"
      className={cn(
        "block whitespace-nowrap rounded-lg border border-border bg-background px-2.5 py-1 text-xs font-medium text-foreground shadow-lg",
        className,
      )}
      {...props}
    >
      {children}
    </motion.span>
  );
}