Heat Calendar

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

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

"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;
}

// 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 { 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/charts/heat-calendar

import { cn } from "@/lib/utils";
import { HeatCalendarContext, useHeatCalendarModel } from "./heat-calendar/context";
import { HeatCalendarGrid } from "./heat-calendar/grid";
import { HeatCalendarLegend } from "./heat-calendar/legend";
import { HeatCalendarTooltip } from "./heat-calendar/tooltip";
import type { HeatCalendarProps } from "./heat-calendar/types";

/** Compose Grid, Tooltip and Legend, or omit children for the complete chart. */
export function HeatCalendar({ children, className, ...props }: HeatCalendarProps) {
  const model = useHeatCalendarModel(props);
  return (
    <HeatCalendarContext.Provider value={model}>
      <div className={cn("w-fit max-w-full", className)}>
        {children === undefined ? (
          <>
            <HeatCalendarGrid>
              <HeatCalendarTooltip />
            </HeatCalendarGrid>
            <HeatCalendarLegend />
          </>
        ) : (
          children
        )}
      </div>
    </HeatCalendarContext.Provider>
  );
}

export { useHeatCalendar } from "./heat-calendar/context";
export { HeatCalendarGrid } from "./heat-calendar/grid";
export { HeatCalendarLegend } from "./heat-calendar/legend";
export { HeatCalendarTooltip } from "./heat-calendar/tooltip";
export type { HeatCalendarCell, HeatCalendarProps, HeatCalendarSelection } from "./heat-calendar/types";

"use client";

import { useReducedMotion } from "motion/react";
import { createContext, useContext, useEffect, useId, useMemo, useRef, useState } from "react";
import { useHoverCapable } from "@/lib/hooks/use-hover-capable";
import type { HeatCalendarCell, HeatCalendarProps, HeatCalendarSelection } from "./types";
import { addDays, CELL, EMPTY, fmtMonth, GAP, MONTH_ROW, mondayOf, PITCH, STEPS, startOfDay } from "./utils";

/**
 * Weeks of activity as a single-hue grid with month labels, so
 * magnitude reads as the strength of one color and the eye needs no legend
 * to find a date. Cells spring in on a diagonal wave. Hovering one lifts it
 * and its neighbours in a small ripple and glides a tooltip with its date and
 * exact count; clicking pins the cell so touch and keyboard get the same
 * readout; from there the grid dims and hovering previews the span from that
 * cell to the pointer with its total, a second click locks it and a third
 * clears it; hovering a legend step filters
 * the grid to that level. Hover lifts are gated to pointer devices, and
 * reduced motion keeps the fades only.
 */
export function useHeatCalendarModel({
  unit = "commits",
  weeks = 16,
  maxCount = 14,
  values,
  endDate,
  color = "var(--accent)",
  selection: controlledSelection,
  defaultSelection = null,
  onSelectionChange,
}: HeatCalendarProps) {
  const reduce = useReducedMotion();
  const canHover = useHoverCapable();
  const [storedHover, setHover] = useState<HeatCalendarCell | null>(null);
  const [internalSelection, setInternalSelection] = useState(defaultSelection);
  const requestedSelection = controlledSelection === undefined ? internalSelection : controlledSelection;
  const setSelection = (next: HeatCalendarSelection | null) => {
    if (controlledSelection === undefined) setInternalSelection(next);
    onSelectionChange?.(next);
  };
  const gridRef = useRef<HTMLDivElement>(null);
  const tooltipId = useId();
  const [step, setStep] = useState<number | null>(null);
  // the entrance wave owns the cells until it has landed; the ripple takes over after
  const [settled, setSettled] = useState(false);
  useEffect(() => {
    const t = setTimeout(() => setSettled(true), reduce ? 0 : (weeks + 7) * 18 + 500);
    return () => clearTimeout(t);
  }, [weeks, reduce]);

  // "today" is read after mount: the server and a viewer on another calendar
  // day must produce the same HTML, so the grid renders first and its dates
  // fill in on the client. An explicit `endDate` is deterministic and skips this.
  const [today, setToday] = useState<Date | null>(null);
  useEffect(() => setToday(startOfDay(new Date())), []);
  const end = useMemo(() => (endDate ? startOfDay(endDate) : today), [endDate, today]);
  const start = useMemo(() => (end ? addDays(mondayOf(end), -(weeks - 1) * 7) : null), [end, weeks]);

  const level = (w: number, d: number) => Math.max(0, Math.min(1, values?.[w]?.[d] ?? 0));
  const bucket = (v: number) => Math.min(4, Math.floor(v * 5));
  const fill = (b: number) => (b === 0 ? EMPTY : `color-mix(in srgb, ${color} ${STEPS[b]}%, transparent)`);
  const count = (v: number) => Math.round(v * maxCount);
  const dateOf = (w: number, d: number) => (start ? addDays(start, w * 7 + d) : null);
  const future = (w: number, d: number) => {
    const date = dateOf(w, d);
    return end !== null && date !== null && date > end;
  };

  const validCell = (cell: HeatCalendarCell) =>
    Number.isInteger(cell.w) &&
    Number.isInteger(cell.d) &&
    cell.w >= 0 &&
    cell.w < weeks &&
    cell.d >= 0 &&
    cell.d < 7 &&
    !future(cell.w, cell.d);
  const selection =
    requestedSelection &&
    validCell(requestedSelection.start) &&
    (!requestedSelection.end || validCell(requestedSelection.end))
      ? requestedSelection
      : null;
  if (requestedSelection && !selection && controlledSelection === undefined) setInternalSelection(null);
  const pinned = selection?.start ?? null;
  const spanEnd = selection?.end ?? null;
  const hover = storedHover && validCell(storedHover) ? storedHover : null;
  if (storedHover && !hover) setHover(null);

  // one label per month, at its first column; the leading label yields if the
  // next month starts within two columns, so two labels never overlap
  const cols = useMemo(() => {
    const list = Array.from({ length: weeks }, (_, w) => {
      const date = start ? addDays(start, w * 7) : null;
      const m = date ? date.getUTCMonth() : -1;
      const fresh =
        start !== null && date !== null && (w === 0 || addDays(start, (w - 1) * 7).getUTCMonth() !== m);
      return { id: `w${w}`, w, m, label: fresh && date ? fmtMonth.format(date) : null };
    });
    if (list[1]?.label || list[2]?.label) list[0].label = null;
    return list;
  }, [start, weeks]);

  // one click anchors a span and dims everything else; hovering then previews
  // the run from the anchor to the pointer and totals it live, and a second
  // click locks it so the number stays on screen while the pointer moves on
  const idx = (c: HeatCalendarCell) => c.w * 7 + c.d;
  const clear = () => {
    setSelection(null);
  };
  const spanTo = spanEnd ?? (pinned ? (hover ?? pinned) : null);
  const span =
    pinned && spanTo
      ? { lo: Math.min(idx(pinned), idx(spanTo)), hi: Math.max(idx(pinned), idx(spanTo)) }
      : null;
  let spanTotal = 0;
  if (span) {
    for (let i = span.lo; i <= span.hi; i++) {
      if (future(Math.floor(i / 7), i % 7)) break;
      spanTotal += count(level(Math.floor(i / 7), i % 7));
    }
  }
  const select = (cell: HeatCalendarCell) => {
    // a locked span clears on the next click anywhere, so leaving it is one press
    if (spanEnd) {
      clear();
    } else if (pinned && idx(pinned) === idx(cell)) {
      setSelection(null);
    } else if (pinned) {
      setSelection({ start: pinned, end: cell });
    } else {
      setSelection({ start: cell });
    }
  };
  /** the cell the grid reacts to: lift, ripple and label highlight follow the pointer */
  const hot = hover ?? spanEnd ?? pinned;
  /** the cell the tooltip hangs from: a locked span keeps it on its end */
  const tip = spanEnd ?? hover ?? pinned;
  const tipDate = tip ? dateOf(tip.w, tip.d) : null;
  const hotMonth = hot ? (dateOf(hot.w, hot.d)?.getUTCMonth() ?? null) : null;
  const tipX = tip ? tip.w * PITCH + CELL / 2 : 0;
  const tipY = tip ? MONTH_ROW + GAP + tip.d * PITCH : 0;
  const tooltip =
    tip && tipDate
      ? {
          date: tipDate,
          count: count(level(tip.w, tip.d)),
          total: spanTotal,
          startDate: start && span ? addDays(start, span.lo) : tipDate,
          endDate: start && span ? addDays(start, span.hi) : tipDate,
          days: span ? span.hi - span.lo + 1 : 1,
        }
      : null;

  return {
    unit,
    weeks,
    reduce,
    canHover,
    hover,
    pinned,
    spanEnd,
    step,
    setStep,
    settled,
    start,
    end,
    level,
    bucket,
    fill,
    count,
    dateOf,
    future,
    cols,
    clear,
    span,
    spanTotal,
    select,
    hot,
    tip,
    tipDate,
    hotMonth,
    tipX,
    tipY,
    setHover,
    gridRef,
    tooltipId,
    tooltip,
    selection,
    setSelection,
  };
}

export const HeatCalendarContext = createContext<ReturnType<typeof useHeatCalendarModel> | null>(null);

/** Read the shared data and selection from any descendant of HeatCalendar. */
export function useHeatCalendar() {
  const context = useContext(HeatCalendarContext);
  if (!context) throw new Error("HeatCalendar parts must be inside HeatCalendar");
  return context;
}

"use client";

import { AnimatePresence, motion } from "motion/react";
import type { ReactNode } from "react";
import { EASE_OUT, SPRING_PRESS } from "@/lib/ease";
import { cn } from "@/lib/utils";
import { useHeatCalendar } from "./context";
import { DAYS, fmtDay, GAP, LIFT, MONTH_ROW, PITCH } from "./utils";

export function HeatCalendarGrid({ children, className }: { children?: ReactNode; className?: string }) {
  const {
    weeks,
    reduce,
    canHover,
    pinned,
    step,
    settled,
    level,
    bucket,
    fill,
    count,
    dateOf,
    future,
    cols,
    clear,
    span,
    select,
    hot,
    hotMonth,
    setHover,
    gridRef,
    tooltipId,
    unit,
  } = useHeatCalendar();
  return (
    <div
      ref={gridRef}
      className={cn("relative grid", className)}
      style={{
        width: weeks * PITCH - GAP,
        maxWidth: "100%",
        gridTemplateColumns: `repeat(${weeks}, minmax(0, 1fr))`,
        gridTemplateRows: `${MONTH_ROW}px repeat(7, auto)`,
        gap: GAP,
      }}
      onPointerLeave={() => setHover(null)}
    >
      {cols.map((c) =>
        c.label ? (
          <span
            key={c.id}
            className={cn(
              "whitespace-nowrap text-[10px] leading-none transition-colors duration-200",
              hotMonth === c.m ? "text-foreground" : "text-muted-foreground",
            )}
            style={{ gridColumn: c.w + 1, gridRow: 1 }}
          >
            {c.label}
          </span>
        ) : null,
      )}
      {cols.map(({ id, w }) =>
        DAYS.map(({ id: dayId, d }) => {
          const date = dateOf(w, d);
          if (future(w, d)) return null;
          const v = level(w, d);
          const b = bucket(v);
          const i = w * 7 + d;
          const on = hot?.w === w && hot?.d === d;
          const isEnd = span ? i === span.lo || i === span.hi : pinned?.w === w && pinned?.d === d;
          const dim = (step !== null && step !== b) || (span !== null && (i < span.lo || i > span.hi));
          // the ripple: the hovered cell rises most, the ring around it a little, two out barely
          const dist = hot ? Math.max(Math.abs(hot.w - w), Math.abs(hot.d - d)) : 9;
          const lift =
            reduce || !canHover ? 1 : dist === 0 ? LIFT[0] : canHover && dist < LIFT.length ? LIFT[dist] : 1;
          return (
            // the outer span owns the legend dim so it never fights the transforms inside
            <span
              key={`${id}-${dayId}`}
              className="relative block aspect-square w-full transition-opacity duration-200"
              style={{
                gridColumn: w + 1,
                gridRow: d + 2,
                opacity: dim ? 0.25 : 1,
                zIndex: lift > 1 ? LIFT.length - dist : 0,
              }}
            >
              {/* the hit area is the cell plus half the gap on every side, so the grid
                    has no dead space between cells and a fast pointer never falls through;
                    the visual inside never takes pointer events, so a lifted neighbour
                    cannot steal a click either */}
              <motion.button
                type="button"
                aria-label={`${count(v)} ${unit}${date ? ` on ${fmtDay.format(date)}` : ""}`}
                data-heat-cell={`${w}-${d}`}
                aria-pressed={isEnd}
                aria-describedby={on ? tooltipId : undefined}
                onPointerEnter={() => setHover({ w, d })}
                onFocus={() => setHover({ w, d })}
                onBlur={() => setHover(null)}
                onClick={() => select({ w, d })}
                onKeyDown={(e) => {
                  if (e.key === "Escape") clear();
                }}
                className="absolute -inset-0.5 block rounded-[5px] outline-none focus-visible:ring-2 focus-visible:ring-ring"
                whileTap={reduce ? undefined : { scale: 0.9, transition: SPRING_PRESS }}
              >
                <motion.span
                  className="pointer-events-none absolute inset-0.5 block rounded-[4px]"
                  style={{
                    background: fill(b),
                    boxShadow: isEnd ? "0 0 0 2px var(--background), 0 0 0 3.5px var(--foreground)" : "none",
                    transition: "box-shadow 150ms",
                  }}
                  // the diagonal wave: each cell arrives (w + d) steps after the corner;
                  // once settled, the ripple spreads out from the hovered cell by distance
                  initial={reduce ? false : { opacity: 0, scale: 0.4 }}
                  animate={
                    settled
                      ? {
                          opacity: 1,
                          scale: lift,
                          transition: { ...SPRING_PRESS, delay: Math.min(dist, 3) * 0.03 },
                        }
                      : {
                          opacity: 1,
                          scale: 1,
                          transition: reduce ? { duration: 0 } : { ...SPRING_PRESS, delay: (w + d) * 0.018 },
                        }
                  }
                >
                  {/* the ring lives INSIDE the cell: inset-0 fills its box and
                        borderRadius:inherit copies its corner, so it always shares the
                        cell's exact size, scale (hover lift included) and roundness and
                        cannot drift however the cells are restyled */}
                  <AnimatePresence>
                    {on && !isEnd ? (
                      <motion.span
                        className="pointer-events-none absolute inset-0 block border-[1.5px]"
                        style={{
                          borderRadius: "inherit",
                          borderColor: "color-mix(in srgb, var(--foreground) 55%, transparent)",
                        }}
                        initial={reduce ? false : { opacity: 0 }}
                        animate={{ opacity: 1 }}
                        exit={{ opacity: 0 }}
                        transition={{ duration: 0.12, ease: EASE_OUT }}
                      />
                    ) : null}
                  </AnimatePresence>
                </motion.span>
              </motion.button>
            </span>
          );
        }),
      )}

      {children}
    </div>
  );
}

"use client";

import { cn } from "@/lib/utils";
import { useHeatCalendar } from "./context";
import { fmtRange, STEPS } from "./utils";

export function HeatCalendarLegend({ className }: { className?: string }) {
  const { start, end, step, setStep, fill, canHover, reduce } = useHeatCalendar();
  return (
    <div className={cn("mt-3 flex flex-wrap items-center justify-between gap-3", className)}>
      <span className="text-xs text-muted-foreground">
        {start && end ? `${fmtRange.format(start)} – ${fmtRange.format(end)}` : "\u00a0"}
      </span>
      {/* hovering a step keeps only cells of that level lit, so the legend doubles as a filter */}
      <span className="flex items-center gap-1" onPointerLeave={() => setStep(null)}>
        <span className="mr-0.5 text-xs text-muted-foreground">less</span>
        {STEPS.map((s, i) => (
          <button
            type="button"
            aria-label={`Show activity level ${i}`}
            aria-pressed={step === i}
            key={s}
            onPointerEnter={() => {
              if (canHover) setStep(i);
            }}
            onFocus={() => setStep(i)}
            onBlur={() => setStep(null)}
            onClick={() => setStep(step === i ? null : i)}
            className="size-3 rounded-[3px] transition-transform duration-150"
            style={{ background: fill(i), transform: !reduce && step === i ? "scale(1.25)" : undefined }}
          />
        ))}
        <span className="ml-0.5 text-xs text-muted-foreground">more</span>
      </span>
    </div>
  );
}

"use client";
import { type ReactNode, useMemo, useState } from "react";
import { NumberTicker } from "@/components/motion/number-ticker";
import { Tooltip } from "@/components/motion/tooltip";
import { cn } from "@/lib/utils";
import { useHeatCalendar } from "./context";
import { fmtDay, fmtRange } from "./utils";

export function HeatCalendarTooltip({
  children,
  className,
}: {
  children?: ReactNode | ((data: NonNullable<ReturnType<typeof useHeatCalendar>["tooltip"]>) => ReactNode);
  className?: string;
}) {
  const { gridRef, tooltipId, tip, tooltip, unit } = useHeatCalendar();
  const [dismissed, setDismissed] = useState<typeof tip>(null);
  const anchorRef = useMemo(() => ({ get current() {
    return tip ? gridRef.current?.querySelector<HTMLElement>(`[data-heat-cell="${tip.w}-${tip.d}"]`) ?? null : null;
  }}), [gridRef, tip]);
  return (
    <Tooltip
      key={tip ? `${tip.w}-${tip.d}` : "closed"}
      open={tooltip !== null && dismissed !== tip}
      onOpenChange={(open) => { if (!open) setDismissed(tip); }}
      id={tooltipId}
      anchorRef={anchorRef}
      className={cn("flex flex-wrap items-center gap-1.5", className)}
      content={tooltip &&
        (typeof children === "function"
          ? children(tooltip)
          : (children ?? (
              <>
                <span className="inline-flex items-center gap-1 font-mono tabular-nums">
                  <NumberTicker
                    value={tooltip.days > 1 ? tooltip.total : tooltip.count}
                    duration={0.35}
                    startOnView={false}
                  />{" "}
                  {unit}
                </span>
                <span className="text-muted-foreground">
                  {tooltip.days > 1 && tooltip.startDate && tooltip.endDate
                    ? `${fmtRange.format(tooltip.startDate)} – ${fmtRange.format(tooltip.endDate)}`
                    : fmtDay.format(tooltip.date)}
                </span>
                {tooltip.days > 1 ? <span className="text-muted-foreground">{tooltip.days} days</span> : null}
              </>
            )))}
    />
  );
}

import type { ReactNode } from "react";

export type HeatCalendarCell = { w: number; d: number };

export interface HeatCalendarSelection {
  start: HeatCalendarCell;
  end?: HeatCalendarCell;
}

export interface HeatCalendarProps {
  /** Noun after every count, e.g. "commits", "ships". */
  unit?: string;
  /** Number of week columns. */
  weeks?: number;
  /** Count a cell at intensity 1 stands for; a cell reads `intensity × maxCount`. */
  maxCount?: number;
  /** `values[week][day]` intensities in 0..1, seven days per week. Missing values are zero. */
  values?: number[][];
  /** Last UTC calendar day of the grid. Defaults to today after mount; explicit dates render identically in every timezone. */
  endDate?: Date;
  /** The single hue. Any CSS color; magnitude maps to its strength, never to a second color. */
  color?: string;
  className?: string;
  children?: ReactNode;
  /** Controlled selection; null clears it. Cell coordinates are zero-based week/day (Monday first). */
  selection?: HeatCalendarSelection | null;
  defaultSelection?: HeatCalendarSelection | null;
  onSelectionChange?: (selection: HeatCalendarSelection | null) => void;
}

/** Five buckets: 0 is the neutral empty cell, 1 to 4 mix the one hue in harder. */
export const STEPS = [0, 24, 46, 70, 94] as const;

export const EMPTY = "color-mix(in srgb, var(--foreground) 6%, transparent)";

/** Cell size and gap; every position in the grid and the tooltip derive from these. */
export const CELL = 16;

export const GAP = 4;

export const PITCH = CELL + GAP;

export const MONTH_ROW = 12;

export const DAYS = Array.from({ length: 7 }, (_, d) => ({ id: `d${d}`, d }));

/** How far a cell rises when it is the hovered one, its neighbour, or two away. */
export const LIFT = [1.3, 1.08, 1.03];

export const startOfDay = (d: Date) => {
  const x = new Date(d);
  x.setUTCHours(0, 0, 0, 0);
  return x;
};

export const addDays = (d: Date, n: number) => {
  const x = new Date(d);
  x.setUTCDate(x.getUTCDate() + n);
  return x;
};

/** Monday on or before `d`, so every column reads Mon to Sun, top to bottom. */
export const mondayOf = (d: Date) => addDays(startOfDay(d), -((d.getUTCDay() + 6) % 7));

export const fmtDay = new Intl.DateTimeFormat("en-US", {
  timeZone: "UTC",
  weekday: "short",
  month: "short",
  day: "numeric",
});

export const fmtMonth = new Intl.DateTimeFormat("en-US", { timeZone: "UTC", month: "short" });

export const fmtRange = new Intl.DateTimeFormat("en-US", { timeZone: "UTC", month: "short", day: "numeric" });

"use client";

import { animate, motion, useInView, useReducedMotion } from "motion/react";
import { useEffect, useMemo, useRef, useState } from "react";
import { EASE_OUT } from "@/lib/ease";
import { cn } from "@/lib/utils";

export interface NumberTickerProps {
  value: number;
  /** Digits to pad to (left). */
  pad?: number;
  /**
   * Fraction digits to keep. The value is rounded to this many places before
   * `format` runs (default 0, whole numbers).
   */
  decimals?: number;
  /** Per-digit roll duration in seconds. */
  duration?: number;
  /** Stagger between digits. */
  stagger?: number;
  /** Render only after the element enters the viewport. */
  startOnView?: boolean;
  prefix?: string;
  suffix?: string;
  /** Add a small blur during digit rolls. */
  blur?: boolean;
  className?: string;
  digitClassName?: string;
  /** Insert locale group separators (commas). Server-component safe. */
  locale?: boolean;
  /** Custom formatter. Client-only — server components must use `locale` instead. */
  format?: (value: number) => string;
}

const DIGIT_HEIGHT_EM = 1.1;
const DIGITS = Array.from({ length: 10 }, (_, n) => n);

export function NumberTicker({
  value,
  pad,
  decimals = 0,
  duration = 0.9,
  stagger = 0.04,
  startOnView = true,
  prefix,
  suffix,
  blur = false,
  className,
  digitClassName,
  locale,
  format,
}: NumberTickerProps) {
  const containerRef = useRef<HTMLSpanElement>(null);
  const inView = useInView(containerRef, { once: true, amount: 0.6 });
  const [armed, setArmed] = useState(!startOnView);

  useEffect(() => {
    if (startOnView && inView) setArmed(true);
  }, [startOnView, inView]);

  const text = useMemo(() => {
    const places = Math.max(0, Math.floor(decimals));
    const factor = 10 ** places;
    const rounded = Math.round(value * factor) / factor;
    const formatted = format
      ? format(rounded)
      : locale
        ? rounded.toLocaleString(undefined, {
            minimumFractionDigits: places,
            maximumFractionDigits: places,
          })
        : rounded.toFixed(places);
    return pad ? formatted.padStart(pad, "0") : formatted;
  }, [value, pad, decimals, format, locale]);
  const glyphs = useMemo(() => {
    const chars = text.split("");
    // Key by place value (position from the right): a changing digit keeps its
    // identity and rolls to the new value instead of remounting and replaying
    // from 0. Growing numbers add glyphs on the left without re-keying the
    // ones, tens, hundreds already on screen.
    return chars.map((char, i) => ({ char, id: `g-${chars.length - 1 - i}` }));
  }, [text]);
  const readableText = `${prefix ?? ""}${text}${suffix ?? ""}`;

  // Stagger is an entrance flourish. Once the reveal has played, value
  // changes roll every digit immediately — a per-digit delay on live updates
  // reads as lag.
  const [entered, setEntered] = useState(false);
  useEffect(() => {
    if (!armed || entered) return;
    const total = (duration + glyphs.length * stagger) * 1000;
    const t = window.setTimeout(() => setEntered(true), total);
    return () => window.clearTimeout(t);
  }, [armed, entered, duration, stagger, glyphs.length]);

  return (
    <span
      ref={containerRef}
      className={cn("inline-flex items-baseline tabular-nums", className)}
    >
      <span className="sr-only">{readableText}</span>
      <span aria-hidden="true" className="inline-flex items-baseline">
        {prefix ? <span>{prefix}</span> : null}
        {glyphs.map(({ char, id }, i) => {
          const isDigit = /\d/.test(char);
          if (!isDigit) {
            return (
              <span key={id} className="inline-block">
                {char}
              </span>
            );
          }
          const digit = Number(char);
          return (
            <Digit
              key={id}
              digit={armed ? digit : 0}
              delay={entered ? 0 : i * stagger}
              duration={duration}
              blur={blur}
              className={digitClassName}
            />
          );
        })}
        {suffix ? <span>{suffix}</span> : null}
      </span>
    </span>
  );
}

function Digit({
  digit,
  delay,
  duration,
  blur,
  className,
}: {
  digit: number;
  delay: number;
  duration: number;
  blur: boolean;
  className?: string;
}) {
  const reduce = useReducedMotion();
  const columnRef = useRef<HTMLSpanElement>(null);

  useEffect(() => {
    if (reduce || !blur || !columnRef.current || !Number.isFinite(digit)) {
      return;
    }

    const node = columnRef.current;
    const controls = animate(
      node,
      { filter: ["blur(10px)", "blur(0px)"] },
      {
        duration: Math.min(duration * 0.75, 0.32),
        delay,
        ease: EASE_OUT,
      },
    );

    return () => {
      controls.stop();
      node.style.filter = "blur(0px)";
    };
  }, [blur, delay, digit, duration, reduce]);

  return (
    // The invisible in-flow digit gives the slot a real text baseline so it
    // lines up with surrounding text; clip-path clips the rolling column
    // without moving that baseline the way overflow: hidden would.
    <span
      className={cn(
        "relative inline-block text-center [clip-path:inset(0)]",
        className,
      )}
      style={{
        height: `${DIGIT_HEIGHT_EM}em`,
        lineHeight: `${DIGIT_HEIGHT_EM}em`,
        width: "1ch",
      }}
    >
      <span className="invisible">{digit}</span>
      <motion.span
        ref={columnRef}
        initial={{ y: 0 }}
        animate={{ y: `-${digit * DIGIT_HEIGHT_EM}em` }}
        transition={
          reduce
            ? { duration: 0 }
            : { duration, delay, ease: EASE_OUT }
        }
        className="absolute inset-x-0 top-0 flex flex-col items-center will-change-[transform,filter]"
      >
        {DIGITS.map((n) => (
          <span
            key={n}
            className="flex h-[1.1em] items-center justify-center leading-none"
          >
            {n}
          </span>
        ))}
      </motion.span>
    </span>
  );
}

"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>
  );
}