tweetCard#

// magicui "Tweet Card" — clean-room reimplementation from the public
// behavior/visual spec only (no upstream source viewed or copied). A card
// that replicates a single social-post embed: avatar/name/verified-badge
// header, body text with mention/hashtag/link styling, optional media grid
// or link-preview card, an optional nested quoted post, and a footer
// timestamp. Shows a pulsing skeleton while data loads and a graceful
// fallback on fetch failure. The tweet-data contract (author, text, media,
// createdAt, optional quoted tweet) and the injectable `fetchTweet` are an
// independently designed shape to build against, not lifted from any
// existing fetching library.

import type {
  BehaviorInstance,
  DomphyElement,
  ElementNode,
  Listener,
  State,
  StyleObject,
} from "@domphy/core";
import { behavior, toState } from "@domphy/core";
import { themeColor, themeDensity, themeSpacing } from "@domphy/theme";
import {
  avatar,
  empty,
  icon,
  paragraph,
  skeleton,
  small,
  strong,
} from "@domphy/ui";
import { fixed } from "../../shared/typography.js";

export interface TweetAuthor {
  name: string;
  handle: string;
  avatarUrl?: string;
  verified?: boolean;
  /** Link to the author's profile (upstream `tweet.user.url`). When set, the
   * avatar, name and handle become clickable anchors to it. */
  profileUrl?: string;
}

export interface TweetMedia {
  url: string;
  alt?: string;
}

export interface TweetLinkPreview {
  url: string;
  title: string;
  description?: string;
  thumbnailUrl?: string;
}

export interface TweetData {
  id: string;
  author: TweetAuthor;
  text: string;
  createdAt: string | number | Date;
  /** Permalink to the post itself (upstream `tweet.url`). When set, the header's
   * platform icon becomes a link to it carrying an sr-only "Link to tweet" label. */
  url?: string;
  media?: TweetMedia[];
  linkPreview?: TweetLinkPreview;
  quotedTweet?: TweetData;
}

export type TweetFetcher = (tweetId: string) => Promise<TweetData>;

export interface TweetCardProps {
  /** Tweet id to resolve via `fetchTweet`. Ignored when `tweet` is provided. */
  tweetId?: string;
  /** Pre-fetched tweet data — renders synchronously with no loading skeleton (the server-rendered path). */
  tweet?: TweetData;
  /** Injectable data source, so the card is testable against static fixtures without a real network call. Defaults to a bundled mock fixture lookup. */
  fetchTweet?: TweetFetcher;
  /** Forces the card's subtree to a specific theme instead of inheriting the ambient page theme. */
  theme?: "light" | "dark";
  showMedia?: boolean;
  showQuotedTweet?: boolean;
}

type TweetPhase = "loading" | "loaded" | "error";

const TWEET_CARD_BEHAVIOR_KEY = "magicui-tweet-card";

interface TweetCardBehaviorProps {
  phase: State<TweetPhase>;
  tweetState: State<TweetData | null>;
  tweet?: TweetData;
  tweetId?: string;
  fetchTweet: TweetFetcher;
}

interface TweetCardBehavior extends BehaviorInstance<TweetCardBehaviorProps> {
  phase: State<TweetPhase>;
  tweetState: State<TweetData | null>;
}

function attachTweetCard(
  _node: ElementNode,
  initialProps: TweetCardBehaviorProps,
): TweetCardBehavior {
  // Persist generation 1's phase/tweetState so a fetch that resolves after
  // an ancestor re-render still writes the State the live children read.
  const phase = initialProps.phase;
  const tweetState = initialProps.tweetState;
  let cancelled = false;
  let latestId = initialProps.tweetId;

  function startFetch(props: TweetCardBehaviorProps): void {
    if (props.tweet || !props.tweetId) return;
    cancelled = false;
    latestId = props.tweetId;
    props
      .fetchTweet(props.tweetId)
      .then((data) => {
        if (cancelled || latestId !== props.tweetId) return;
        tweetState.set(data);
        phase.set("loaded");
      })
      .catch(() => {
        if (cancelled || latestId !== props.tweetId) return;
        phase.set("error");
      });
  }

  startFetch(initialProps);

  return {
    phase,
    tweetState,
    update(next) {
      if (next.tweet) {
        tweetState.set(next.tweet);
        phase.set("loaded");
        return;
      }
      if (next.tweetId && next.tweetId !== latestId) {
        cancelled = true;
        phase.set("loading");
        startFetch(next);
      }
    },
    destroy() {
      cancelled = true;
    },
  };
}

function elementNodeOf(listener: Listener): ElementNode | null {
  const fromListener = (listener as { elementNode?: ElementNode }).elementNode;
  if (fromListener && typeof fromListener.getBehavior === "function") {
    return fromListener;
  }
  if (typeof (listener as unknown as ElementNode).getBehavior === "function") {
    return listener as unknown as ElementNode;
  }
  return null;
}

function tweetCardState(
  listener: Listener,
  fallbackPhase: State<TweetPhase>,
  fallbackTweet: State<TweetData | null>,
): { phase: State<TweetPhase>; tweetState: State<TweetData | null> } {
  const instance = elementNodeOf(listener)?.getBehavior<TweetCardBehavior>(
    TWEET_CARD_BEHAVIOR_KEY,
  );
  if (instance?.phase && instance.tweetState) {
    return { phase: instance.phase, tweetState: instance.tweetState };
  }
  return { phase: fallbackPhase, tweetState: fallbackTweet };
}

const DEFAULT_TWEET: TweetData = {
  id: "domphy-demo-1",
  author: {
    name: "Ada Byte",
    handle: "adabyte",
    verified: true,
    profileUrl: "https://domphy.com/@adabyte",
  },
  text: "Shipping a whole design system as plain objects keyed by HTML tag. No JSX, no virtual DOM. @domphy #buildinpublic https://domphy.com",
  createdAt: "2026-06-18T15:32:00Z",
  url: "https://domphy.com/@adabyte/posts/domphy-demo-1",
  linkPreview: {
    url: "https://domphy.com",
    title: "Domphy — the AI-friendly UI framework",
    description:
      "Patch-based UI for native elements, with a runtime built for reactivity and theming.",
  },
};

const MOCK_TWEET_FIXTURES: Record<string, TweetData> = {
  [DEFAULT_TWEET.id]: DEFAULT_TWEET,
};

/**
 * Default injectable fetcher: resolves from an in-memory fixture table
 * (falling back to a synthesized placeholder tweet for unknown ids) after a
 * short simulated network delay. No real network request is made — callers
 * that need live data should pass their own `fetchTweet`.
 */
const defaultFetchTweet: TweetFetcher = (tweetId) =>
  new Promise((resolve) => {
    setTimeout(() => {
      resolve(
        MOCK_TWEET_FIXTURES[tweetId] ?? {
          id: tweetId,
          author: { name: "Unknown Author", handle: "unknown" },
          text: "This is placeholder content for a tweet id with no bundled fixture.",
          createdAt: Date.now(),
        },
      );
    }, 400);
  });

function formatTweetDate(createdAt: TweetData["createdAt"]): string {
  const date = createdAt instanceof Date ? createdAt : new Date(createdAt);
  if (Number.isNaN(date.getTime())) return "";
  return date.toLocaleString(undefined, {
    month: "short",
    day: "numeric",
    year: "numeric",
    hour: "numeric",
    minute: "2-digit",
  });
}

/** Caps a string at `length`, replacing the tail with an ellipsis — mirrors
 * upstream's `truncate` used on the display name (20) and handle (16). */
function truncate(value: string, length: number): string {
  if (value.length <= length) return value;
  return `${value.slice(0, length - 3)}...`;
}

/** Visually-hidden ("sr-only") style, same recipe as this package's other
 * sr-only usages (auroraText, kineticText). Carries the accessible "Link to
 * tweet" label behind the decorative, aria-hidden platform icon. */
const SR_ONLY_STYLE: StyleObject = {
  position: "absolute",
  width: "1px",
  height: "1px",
  padding: "0",
  margin: "-1px",
  overflow: "hidden",
  clip: "rect(0, 0, 0, 0)",
  whiteSpace: "nowrap",
  border: "0",
};

/** Body-entity (@mention / #hashtag / URL) styling. Upstream renders these as
 * muted, de-emphasized text below the body copy (`text-muted-foreground`), no
 * underline, brightening to the foreground color on hover (`hover:text-foreground
 * transition-colors`). Two deliberate deviations for WCAG: these are interactive
 * links (essential content), so they rest at the `text` tone (shift-9) — muted
 * (shift-8) measures ~4.06:1, below AA for normal text — and they carry an
 * underline, since inside a paragraph of full-strength text a color-only
 * distinction fails axe `link-in-text-block`. */
const ENTITY_STYLE: StyleObject = {
  color: (listener: Listener) => themeColor(listener, "shift-9", "neutral"),
  textDecoration: fixed("underline"),
  fontWeight: fixed(400),
  transition: "color 150ms ease",
  "&:hover": {
    color: (listener: Listener) => themeColor(listener, "shift-10", "neutral"),
  },
};

/** Small outline checkmark badge shown next to a verified author's name. */
function verifiedBadgeIcon(): DomphyElement<"span"> {
  return {
    span: [
      {
        svg: [
          { circle: null, cx: "12", cy: "12", r: "9" },
          { polyline: null, points: "8,12.5 11,15.5 16,9" },
        ],
        viewBox: "0 0 24 24",
        fill: "none",
        stroke: "currentColor",
        strokeWidth: "2",
        strokeLinecap: "round",
        strokeLinejoin: "round",
        role: "img",
        ariaLabel: "Verified account",
        style: { width: "100%", height: "100%" },
      } as DomphyElement<"svg">,
    ],
    $: [icon({ color: "info" })],
    style: { width: themeSpacing(4), height: themeSpacing(4), flexShrink: "0" },
  };
}

/** Small generic chat-bubble mark standing in for a "platform" logo — a
 * deliberately original, generic glyph, not a reproduction of any specific
 * platform's trademarked logo. */
function platformLogoIcon(): DomphyElement<"span"> {
  return {
    span: [
      {
        svg: [
          {
            path: null,
            d: "M4 5h16a1 1 0 0 1 1 1v9a1 1 0 0 1-1 1H9l-4 3v-3H4a1 1 0 0 1-1-1V6a1 1 0 0 1 1-1z",
          },
        ],
        viewBox: "0 0 24 24",
        fill: "none",
        stroke: "currentColor",
        strokeWidth: "1.75",
        strokeLinecap: "round",
        strokeLinejoin: "round",
        role: "img",
        ariaHidden: "true",
        style: { width: "100%", height: "100%" },
      } as DomphyElement<"svg">,
    ],
    ariaHidden: "true",
    $: [icon({ color: "neutral" })],
    style: {
      width: themeSpacing(4),
      height: themeSpacing(4),
      flexShrink: "0",
      // Upstream: `hover:text-foreground hover:scale-105 transition-all`.
      transition: "color 150ms ease, transform 150ms ease",
      "&:hover": {
        color: (listener: Listener) =>
          themeColor(listener, "shift-10", "neutral"),
        transform: "scale(1.05)",
      },
    },
  };
}

function tweetHeader(data: TweetData): DomphyElement<"div"> {
  const author = data.author;
  const initials =
    author.name
      .split(/\s+/)
      .map((word) => word[0])
      .slice(0, 2)
      .join("")
      .toUpperCase() || "?";
  const profileUrl = author.profileUrl;

  // Avatar — a profile anchor when a profileUrl exists (upstream wraps the
  // `<img>` in `<a href={tweet.user.url}>`), otherwise the bare avatar span.
  const avatarSpan: DomphyElement<"span"> = {
    span: author.avatarUrl
      ? [
          {
            img: null,
            src: author.avatarUrl,
            alt: author.name,
            loading: "lazy" as const,
          },
        ]
      : initials,
    $: [avatar({ color: "primary" })],
  };
  const avatarNode: DomphyElement = profileUrl
    ? {
        a: [avatarSpan],
        href: profileUrl,
        target: "_blank",
        rel: "noreferrer",
        style: {
          display: "inline-flex",
          flexShrink: "0",
          textDecoration: fixed("none"),
        },
      }
    : avatarSpan;

  // Name row (name + verified badge) — truncated to 20 chars like upstream.
  const nameRowChildren: DomphyElement[] = [
    { strong: truncate(author.name, 20), $: [strong()] },
  ];
  if (author.verified) nameRowChildren.push(verifiedBadgeIcon());
  const nameNode: DomphyElement = profileUrl
    ? {
        a: nameRowChildren,
        href: profileUrl,
        target: "_blank",
        rel: "noreferrer",
        style: {
          display: "flex",
          alignItems: "center",
          gap: themeSpacing(1),
          whiteSpace: "nowrap",
          textDecoration: fixed("none"),
          color: "inherit",
          transition: "opacity 150ms ease",
          "&:hover": { opacity: "0.8" },
        },
      }
    : {
        div: nameRowChildren,
        style: { display: "flex", alignItems: "center", gap: themeSpacing(1) },
      };

  // Handle — truncated to 16 chars; a muted profile anchor (upstream
  // `text-muted-foreground hover:text-foreground text-sm transition-colors`)
  // or the plain `small` when no profileUrl.
  const handleText = `@${truncate(author.handle, 16)}`;
  const handleNode: DomphyElement = profileUrl
    ? {
        a: handleText,
        href: profileUrl,
        target: "_blank",
        rel: "noreferrer",
        dataSize: "decrease-1",
        style: {
          color: (listener: Listener) =>
            themeColor(listener, "shift-9", "neutral"),
          textDecoration: fixed("none"),
          transition: "color 150ms ease",
          "&:hover": {
            color: (listener: Listener) =>
              themeColor(listener, "shift-10", "neutral"),
          },
        },
      }
    : { small: handleText, $: [small()] };

  // Platform icon — a link to the tweet (upstream `<a href={tweet.url}>` with an
  // sr-only "Link to tweet" label) when a url exists, otherwise the inert icon.
  const platformIcon = platformLogoIcon();
  const platformNode: DomphyElement = data.url
    ? {
        a: [{ span: "Link to tweet", style: SR_ONLY_STYLE }, platformIcon],
        href: data.url,
        target: "_blank",
        rel: "noreferrer",
        style: {
          display: "inline-flex",
          alignItems: "flex-start",
          flexShrink: "0",
          marginInlineStart: "auto",
          textDecoration: fixed("none"),
          color: "inherit",
        },
      }
    : {
        ...platformIcon,
        style: { ...platformIcon.style, marginInlineStart: "auto" },
      };

  return {
    div: [
      avatarNode,
      {
        div: [nameNode, handleNode],
        style: {
          display: "flex",
          flexDirection: "column",
          minWidth: "0",
          overflow: "hidden",
        },
      },
      platformNode,
    ],
    style: { display: "flex", alignItems: "flex-start", gap: themeSpacing(3) },
  };
}

/** Splits the tweet body into plain text runs and clickable @mention / #hashtag / URL entities. */
function tweetTextBody(text: string): DomphyElement<"p"> {
  const tokens = text.split(/(\s+)/);
  const children: (string | DomphyElement<"a">)[] = tokens.map(
    (token, index) => {
      if (/^https?:\/\/\S+/.test(token)) {
        return {
          a: token,
          href: token,
          target: "_blank",
          rel: "noopener noreferrer",
          _key: `entity-${index}`,
          style: ENTITY_STYLE,
        };
      }
      if (/^[@#]\w+/.test(token)) {
        return {
          a: token,
          href: "#",
          _key: `entity-${index}`,
          style: ENTITY_STYLE,
        };
      }
      return token;
    },
  );

  return { p: children as DomphyElement<"p">["p"], $: [paragraph()] };
}

function mediaGrid(media: TweetMedia[]): DomphyElement<"div"> {
  const shown = media.slice(0, 4);
  const columns = shown.length === 1 ? 1 : 2;

  return {
    div: shown.map((item, index) => ({
      img: null,
      src: item.url,
      alt: item.alt ?? "",
      loading: "lazy" as const,
      _key: `media-${index}`,
      style: {
        width: "100%",
        height: "100%",
        aspectRatio: shown.length === 1 ? "16 / 9" : "1 / 1",
        objectFit: "cover",
        display: "block",
      },
    })),
    style: {
      display: "grid",
      gridTemplateColumns: `repeat(${columns}, 1fr)`,
      gap: themeSpacing(0.5),
      borderRadius: (listener: Listener) =>
        themeSpacing(themeDensity(listener) * 3),
      overflow: "hidden",
      color: (listener: Listener) => themeColor(listener, "shift-9"),
      outline: (listener: Listener) =>
        `1px solid ${themeColor(listener, "shift-3")}`,
      outlineOffset: "-1px",
    },
  };
}

function linkPreviewCard(preview: TweetLinkPreview): DomphyElement<"a"> {
  let hostname = preview.url;
  try {
    hostname = new URL(preview.url).hostname;
  } catch {
    // Malformed preview URL — fall back to showing the raw string.
  }

  const detailChildren: DomphyElement[] = [
    { strong: preview.title, $: [strong()] },
  ];
  if (preview.description)
    detailChildren.push({ small: preview.description, $: [small()] });
  detailChildren.push({ small: hostname, $: [small()] });

  const cardChildren: DomphyElement[] = [];
  if (preview.thumbnailUrl) {
    cardChildren.push({
      img: null,
      src: preview.thumbnailUrl,
      alt: "",
      loading: "lazy",
      style: {
        width: "100%",
        display: "block",
        objectFit: "cover",
        aspectRatio: "2 / 1",
      },
    });
  }
  cardChildren.push({
    div: detailChildren,
    style: {
      display: "flex",
      flexDirection: "column",
      gap: themeSpacing(1),
      padding: (listener: Listener) => themeSpacing(themeDensity(listener) * 3),
    },
  });

  return {
    a: cardChildren,
    href: preview.url,
    target: "_blank",
    rel: "noopener noreferrer",
    style: {
      display: "block",
      textDecoration: () => "none",
      borderRadius: (listener: Listener) =>
        themeSpacing(themeDensity(listener) * 3),
      overflow: "hidden",
      outline: (listener: Listener) =>
        `1px solid ${themeColor(listener, "shift-3")}`,
      outlineOffset: "-1px",
      color: (listener: Listener) => themeColor(listener, "shift-9"),
      backgroundColor: (listener: Listener) => themeColor(listener, "inherit"),
      "&:hover": {
        backgroundColor: (listener: Listener) =>
          themeColor(listener, "increase-1"),
      },
    },
  };
}

function tweetFooter(createdAt: TweetData["createdAt"]): DomphyElement<"div"> {
  return {
    div: [{ small: formatTweetDate(createdAt), $: [small()] }],
    style: {
      display: "flex",
      color: (listener: Listener) => themeColor(listener, "shift-9"),
      borderTop: (listener: Listener) =>
        `1px solid ${themeColor(listener, "shift-3")}`,
      paddingTop: (listener: Listener) =>
        themeSpacing(themeDensity(listener) * 2),
    },
  };
}

interface TweetBodyOptions {
  showMedia: boolean;
  showQuotedTweet: boolean;
  /** Caps quoted-tweet nesting at one level, so a quote never renders its own quote. */
  depth: number;
}

function tweetBody(
  data: TweetData,
  options: TweetBodyOptions,
): DomphyElement<"div"> {
  const children: DomphyElement[] = [
    tweetHeader(data),
    tweetTextBody(data.text),
  ];

  if (options.showMedia && data.media?.length)
    children.push(mediaGrid(data.media));
  if (data.linkPreview) children.push(linkPreviewCard(data.linkPreview));
  if (options.showQuotedTweet && data.quotedTweet && options.depth < 1) {
    children.push({
      div: [
        tweetBody(data.quotedTweet, {
          showMedia: options.showMedia,
          showQuotedTweet: false,
          depth: options.depth + 1,
        }),
      ],
      dataTone: "shift-1",
      style: {
        borderRadius: (listener: Listener) =>
          themeSpacing(themeDensity(listener) * 3),
        padding: (listener: Listener) =>
          themeSpacing(themeDensity(listener) * 3),
        backgroundColor: (listener: Listener) =>
          themeColor(listener, "inherit"),
        color: (listener: Listener) => themeColor(listener, "shift-10"),
        outline: (listener: Listener) =>
          `1px solid ${themeColor(listener, "shift-3")}`,
        outlineOffset: "-1px",
      },
    });
  }
  children.push(tweetFooter(data.createdAt));

  return {
    div: children,
    style: {
      display: "flex",
      flexDirection: "column",
      gap: (listener: Listener) => themeSpacing(themeDensity(listener) * 3),
    },
  };
}

function tweetSkeleton(): DomphyElement<"div"> {
  return {
    div: [
      {
        div: [
          {
            span: null,
            $: [skeleton()],
            style: {
              width: themeSpacing(9),
              height: themeSpacing(9),
              borderRadius: "50%",
            },
          },
          {
            div: [
              { span: null, $: [skeleton()], style: { width: "40%" } },
              { span: null, $: [skeleton()], style: { width: "25%" } },
            ],
            style: {
              display: "flex",
              flexDirection: "column",
              gap: themeSpacing(1),
              flex: "1 1 auto",
            },
          },
        ],
        style: { display: "flex", gap: themeSpacing(3), alignItems: "center" },
      },
      { span: null, $: [skeleton()], style: { width: "100%" } },
      { span: null, $: [skeleton()], style: { width: "80%" } },
    ],
    ariaLabel: "Loading tweet",
    style: { display: "flex", flexDirection: "column", gap: themeSpacing(3) },
  };
}

function tweetFallback(): DomphyElement<"div"> {
  return {
    div: [{ span: "🚫" }, { p: "This post is unavailable.", $: [paragraph()] }],
    $: [empty()],
  };
}

/**
 * A card replicating a single social-post embed, with header/body/media/
 * link-preview/quoted-post/footer regions, a loading skeleton, and a
 * fallback state on fetch failure. Call with no arguments for a working
 * demo tweet (rendered synchronously — no loading flicker). Pass `tweetId`
 * (with an optional injectable `fetchTweet`) to exercise the async
 * loading/error states instead.
 */
function tweetCard(props: TweetCardProps = {}): DomphyElement<"div"> {
  const fetchTweet = props.fetchTweet ?? defaultFetchTweet;
  const showMedia = props.showMedia ?? true;
  const showQuotedTweet = props.showQuotedTweet ?? true;

  const initialTweet = props.tweet ?? (props.tweetId ? null : DEFAULT_TWEET);
  const phase = toState<TweetPhase>(initialTweet ? "loaded" : "loading");
  const tweetState = toState<TweetData | null>(initialTweet);

  return {
    div: (listener: Listener) => {
      const live = tweetCardState(listener, phase, tweetState);
      const currentPhase = live.phase.get(listener);
      // Each phase gets a distinct `_key` so the reconciler replaces the
      // single child outright on a phase transition instead of positionally
      // patching the old (structurally different) DOM subtree in place —
      // without this, stale attributes/nodes from the previous phase can
      // leak through (e.g. the skeleton's `aria-label` surviving onto the
      // loaded body).
      if (currentPhase === "loading")
        return [{ ...tweetSkeleton(), _key: "skeleton" }];
      const data = live.tweetState.get(listener);
      if (currentPhase === "error" || !data)
        return [{ ...tweetFallback(), _key: "error" }];
      return [
        {
          ...tweetBody(data, { showMedia, showQuotedTweet, depth: 0 }),
          _key: `body-${data.id}`,
        },
      ];
    },
    role: "article",
    dataTheme: props.theme,
    dataTone: "shift-0",
    style: {
      display: "block",
      width: "100%",
      maxWidth: themeSpacing(120),
      borderRadius: (listenerValue: Listener) =>
        themeSpacing(themeDensity(listenerValue) * 3),
      padding: (listenerValue: Listener) =>
        themeSpacing(themeDensity(listenerValue) * 4),
      backgroundColor: (listenerValue: Listener) =>
        themeColor(listenerValue, "inherit"),
      color: (listenerValue: Listener) => themeColor(listenerValue, "shift-10"),
      outline: (listenerValue: Listener) =>
        `1px solid ${themeColor(listenerValue, "shift-3")}`,
      outlineOffset: "-1px",
    },
    ...behavior<TweetCardBehaviorProps>(
      TWEET_CARD_BEHAVIOR_KEY,
      attachTweetCard,
      {
        phase,
        tweetState,
        tweet: props.tweet,
        tweetId: props.tweetId,
        fetchTweet,
      },
    ),
  };
}

export { tweetCard, defaultFetchTweet };