Craft

Diff Approval Card

Review a proposed update word by word, pick which changes to keep, apply them, and undo.

Overview

An approval card for proposed changes. Collapsed, it lists which fields change. Open it to see each one as a word-level diff: removed words struck through in red, added words in green, either inline or side by side. Values that were mostly rewritten show as a whole replacement instead of a confetti of edits. Untick a field to leave it as it is, and the Apply button counts what you'll apply. Unchanged fields fold away. Applying shows a saving state, then the removed words blur away and the added ones settle into plain text. Failures shake the card and explain what happened, and there's undo, plus dismiss and bring back.

Installation

Install dependencies:

$ pnpm add motion

Add the utility function for class merging:

lib/utils.ts
tsx
import { ClassValue, clsx } from "clsx";import { twMerge } from "tailwind-merge";
export function cn(...inputs: ClassValue[]) {  return twMerge(clsx(inputs));}

Copy the component code into your project:

components/ui/diff-approval-card.tsx
tsx
"use client";
import { useEffect, useId, useMemo, useRef, useState } from "react";import type { ButtonHTMLAttributes, Ref } from "react";import {  AnimatePresence,  LayoutGroup,  motion,  useAnimate,  useReducedMotion,} from "motion/react";import { cn } from "@/lib/utils";
export type DiffField = {  id: string;  label: string;  before: string;  after: string;};
export type DiffApprovalCardProps = {  title?: string;  description?: string;  fields: DiffField[];  defaultExpanded?: boolean;  defaultView?: "inline" | "split";  /**   * Called with the resulting fields: `after` holds the value that will be current   * (the proposal where included, the original where excluded). Reject to keep reviewing.   */  onAccept?: (fields: DiffField[]) => void | Promise<void>;  /** Roll back an accepted update. Undo is offered when this is set, or when there's no onAccept. */  onUndo?: (fields: DiffField[]) => void | Promise<void>;  /** Called when the proposal is discarded. */  onReject?: () => void;  className?: string;};
type Seg = { type: "same" | "add" | "del"; text: string };type State = "compact" | "review" | "accepted" | "rejected";
const EASE_OUT = [0.23, 1, 0.32, 1] as const;const HEIGHT = { type: "spring" as const, bounce: 0.1, duration: 0.5 };
/** Word-level diff via LCS. Each word keeps its trailing space; mostly-rewritten values show as a full replacement. */function diffWords(a: string, b: string): Seg[] {  const A = a.match(/\S+\s*|\s+/g) ?? [];  const B = b.match(/\S+\s*|\s+/g) ?? [];  const dp = Array.from({ length: A.length + 1 }, () =>    new Array<number>(B.length + 1).fill(0),  );  for (let i = A.length - 1; i >= 0; i--)    for (let j = B.length - 1; j >= 0; j--)      dp[i][j] =        A[i] === B[j]          ? dp[i + 1][j + 1] + 1          : Math.max(dp[i + 1][j], dp[i][j + 1]);  const out: Seg[] = [];  const push = (type: Seg["type"], text: string) => {    const last = out[out.length - 1];    if (last && last.type === type) last.text += text;    else out.push({ type, text });  };  let i = 0;  let j = 0;  while (i < A.length && j < B.length) {    if (A[i] === B[j]) {      push("same", A[i]);      i++;      j++;    } else if (dp[i + 1][j] >= dp[i][j + 1]) push("del", A[i++]);    else push("add", B[j++]);  }  while (i < A.length) push("del", A[i++]);  while (j < B.length) push("add", B[j++]);  const same = out    .filter((x) => x.type === "same")    .reduce((n, x) => n + x.text.trim().length, 0);  if (same / Math.max(1, Math.max(a.length, b.length)) < 0.3) {    return [      ...(a ? [{ type: "del" as const, text: a }] : []),      ...(b ? [{ type: "add" as const, text: b }] : []),    ];  }  return out;}
function Icon({ d, className }: { d: string; className?: string }) {  return (    <svg      aria-hidden      viewBox="0 0 16 16"      className={cn("size-3.5 shrink-0", className)}      fill="none"      stroke="currentColor"      strokeWidth="1.8"      strokeLinecap="round"      strokeLinejoin="round"    >      <path d={d} />    </svg>  );}
export function DiffApprovalCard({  title = "Storefront details",  description = "A small update, ready for your review.",  fields,  defaultExpanded = false,  defaultView = "inline",  onAccept,  onUndo,  onReject,  className,}: DiffApprovalCardProps) {  const reduce = !!useReducedMotion();  const uid = useId();  const [state, setState] = useState<State>(    defaultExpanded ? "review" : "compact",  );  const [view, setView] = useState<"inline" | "split">(defaultView);  const changed = useMemo(    () => fields.filter((f) => f.before !== f.after),    [fields],  );  const unchanged = useMemo(    () => fields.filter((f) => f.before === f.after),    [fields],  );  const [included, setIncluded] = useState<Set<string>>(    () => new Set(changed.map((f) => f.id)),  );  const [showSame, setShowSame] = useState(false);  const [pending, setPending] = useState<"accept" | "undo" | null>(null);  const [error, setError] = useState("");  const [scope, animateEl] = useAnimate<HTMLElement>();  const shake = () => {    if (!reduce && scope.current)      animateEl(scope.current, { x: [0, -6, 6, -4, 4, 0] }, { duration: 0.4 });  };  const [applied, setApplied] = useState<Set<string>>(new Set());  const toggleRef = useRef<HTMLButtonElement>(null);  const mounted = useRef(true);  useEffect(() => {    mounted.current = true;    return () => {      mounted.current = false;    };  }, []);
  const diffs = useMemo(    () =>      Object.fromEntries(        changed.map((f) => [f.id, diffWords(f.before, f.after)]),      ),    [changed],  );  const count = included.size;  const accepted = state === "accepted";  const rejected = state === "rejected";  const open = state === "review" || accepted;  const canUndo = !!onUndo || !onAccept;
  // Height follows content.  const innerRef = useRef<HTMLDivElement>(null);  const [h, setH] = useState<number | "auto">("auto");  useEffect(() => {    const el = innerRef.current;    if (!el) return;    const ro = new ResizeObserver(([e]) => setH(e.contentRect.height));    ro.observe(el);    return () => ro.disconnect();  }, []);
  const result = (ids: Set<string>) =>    fields.map((f) => ({ ...f, after: ids.has(f.id) ? f.after : f.before }));
  const accept = async () => {    if (pending || !count) return;    setPending("accept");    setError("");    const snapshot = new Set(included);    try {      await onAccept?.(result(snapshot));      if (!mounted.current) return;      setApplied(snapshot);      setState("accepted");    } catch {      if (!mounted.current) return;      setError("Couldn’t apply this update. Nothing was changed. Try again.");      shake();    } finally {      if (mounted.current) setPending(null);    }  };  const undo = async () => {    if (pending) return;    setPending("undo");    setError("");    try {      await onUndo?.(result(applied));      if (!mounted.current) return;      setApplied(new Set());      setState("review");    } catch {      if (!mounted.current) return;      setError("Couldn’t undo this update. Try again.");      shake();    } finally {      if (mounted.current) setPending(null);    }  };  const toggleField = (id: string) =>    setIncluded((s) => {      const next = new Set(s);      if (next.has(id)) next.delete(id);      else next.add(id);      return next;    });  const allOn = count === changed.length;
  const headline = accepted    ? "Update applied"    : rejected      ? "Proposal dismissed"      : title;  const sub = accepted    ? `${applied.size} of ${changed.length} ${changed.length === 1 ? "change" : "changes"} now current.`    : rejected      ? "The current version stays as it is."      : description;
  return (    <motion.section      aria-labelledby={`${uid}-title`}      ref={scope}      aria-busy={!!pending}      onKeyDown={(e) => {        if (e.key === "Escape" && state === "review" && !pending) {          e.preventDefault();          setState("compact");          toggleRef.current?.focus();        }      }}      className={cn(        "mx-auto w-full max-w-2xl overflow-hidden rounded-[20px] bg-(--color-paper) text-(--color-ink)",        "shadow-[0_0_0_1px_var(--color-rule),0_1px_2px_rgba(0,0,0,0.04),0_18px_44px_-24px_rgba(0,0,0,0.28)]",        "[--diff-add:oklch(50%_0.12_155)] [--diff-del:oklch(54%_0.17_25)] dark:[--diff-add:oklch(80%_0.13_155)] dark:[--diff-del:oklch(76%_0.13_25)]",        className,      )}    >      {/* Header */}      <div className="flex items-start justify-between gap-4 px-5 pt-5 pb-4 sm:px-6">        <div className="flex min-w-0 items-center gap-3">          <motion.span            aria-hidden            animate={{ scale: accepted ? [1, 1.15, 1] : 1 }}            transition={{ duration: 0.4 }}            className={cn(              "grid size-10 shrink-0 place-items-center rounded-[12px] transition-colors duration-300",              accepted                ? "bg-(--diff-add) text-(--color-paper)"                : "bg-(--color-paper-2) text-(--color-ink-2) shadow-[inset_0_0_0_1px_var(--color-rule)]",            )}          >            <AnimatePresence initial={false} mode="popLayout">              <motion.span                key={                  state === "accepted"                    ? "ok"                    : state === "rejected"                      ? "x"                      : "doc"                }                initial={{ opacity: 0, scale: 0.5, rotate: -30 }}                animate={{ opacity: 1, scale: 1, rotate: 0 }}                exit={{ opacity: 0, scale: 0.5, rotate: 30 }}                transition={{ type: "spring", bounce: 0.4, duration: 0.45 }}              >                {accepted ? (                  <svg                    viewBox="0 0 16 16"                    className="size-[18px]"                    fill="none"                    stroke="currentColor"                    strokeWidth="2.2"                    strokeLinecap="round"                    strokeLinejoin="round"                  >                    <motion.path                      d="M3.5 8.5 6.5 11.5 12.5 4.5"                      initial={{ pathLength: 0 }}                      animate={{ pathLength: 1 }}                      transition={{ duration: 0.4, delay: 0.1 }}                    />                  </svg>                ) : rejected ? (                  <Icon                    d="M4.5 4.5l7 7M11.5 4.5l-7 7"                    className="size-[18px]"                  />                ) : (                  <Icon                    d="M9.5 2H4.5A1.5 1.5 0 0 0 3 3.5v9A1.5 1.5 0 0 0 4.5 14h7a1.5 1.5 0 0 0 1.5-1.5V5.5L9.5 2Zm0 0v3.5H13M6 9h4M8 7v4"                    className="size-[18px]"                  />                )}              </motion.span>            </AnimatePresence>          </motion.span>          <div className="relative min-w-0">            <AnimatePresence initial={false} mode="popLayout">              <motion.div                key={state === "review" ? "compact" : state}                initial={{ opacity: 0, y: 6, filter: "blur(4px)" }}                animate={{ opacity: 1, y: 0, filter: "blur(0px)" }}                exit={{ opacity: 0, y: -6, filter: "blur(4px)" }}                transition={{ duration: 0.25, ease: EASE_OUT }}              >                <div                  id={`${uid}-title`}                  className="truncate text-[15px] font-semibold tracking-tight"                >                  {headline}                </div>                <div className="mt-0.5 text-[12.5px] text-pretty text-(--color-neutral)">                  {sub}                </div>              </motion.div>            </AnimatePresence>          </div>        </div>        <span          className={cn(            "inline-flex h-6 shrink-0 items-center gap-1 rounded-full px-2.5 text-[11.5px] font-medium tabular-nums transition-colors duration-300",            accepted              ? "bg-[color-mix(in_oklch,var(--diff-add)_14%,transparent)] text-(--diff-add)"              : "bg-(--color-paper-2) text-(--color-ink-2) shadow-[inset_0_0_0_1px_var(--color-rule)]",          )}        >          {accepted            ? "Applied"            : rejected              ? "Dismissed"              : `${changed.length} ${changed.length === 1 ? "change" : "changes"}`}        </span>      </div>
      {/* Compact preview: which fields change */}      <AnimatePresence initial={false}>        {state === "compact" ? (          <motion.div            key="chips"            initial={{ opacity: 0, height: 0 }}            animate={{ opacity: 1, height: "auto" }}            exit={{ opacity: 0, height: 0 }}            transition={              reduce                ? { duration: 0 }                : { height: HEIGHT, opacity: { duration: 0.2 } }            }            className="overflow-hidden"          >            <div className="flex flex-wrap gap-1.5 px-5 pb-4 sm:px-6">              {changed.length ? (                changed.map((f, i) => (                  <motion.span                    key={f.id}                    initial={reduce ? false : { opacity: 0, y: 4 }}                    animate={{ opacity: 1, y: 0 }}                    transition={{ delay: reduce ? 0 : i * 0.04 }}                    className="inline-flex items-center gap-1.5 rounded-full bg-(--color-paper-2) px-2.5 py-1 text-[12px] text-(--color-ink-2) shadow-[inset_0_0_0_1px_var(--color-rule)]"                  >                    <span className="size-1.5 rounded-full bg-(--diff-add)" />                    {f.label}                  </motion.span>                ))              ) : (                <span className="text-[12.5px] text-(--color-neutral)">                  Both versions are already identical.                </span>              )}            </div>          </motion.div>        ) : null}      </AnimatePresence>
      {/* Review */}      <motion.div        initial={false}        animate={{ height: open ? h : 0, opacity: open ? 1 : 0 }}        transition={          reduce            ? { duration: 0 }            : { height: HEIGHT, opacity: { duration: 0.25 } }        }        className="overflow-hidden"        aria-hidden={!open}        inert={!open}      >        <div ref={innerRef} id={`${uid}-review`}>          {state === "review" ? (            <div className="flex flex-wrap items-center justify-between gap-2 border-t border-(--color-rule) px-5 py-2.5 sm:px-6">              <button                type="button"                onClick={() =>                  setIncluded(                    allOn ? new Set() : new Set(changed.map((f) => f.id)),                  )                }                className="flex items-center gap-2 rounded-full py-1 pr-2 text-[12px] font-medium text-(--color-ink-2) outline-none hover:text-(--color-ink) focus-visible:ring-2 focus-visible:ring-(--color-focus)"              >                <Check                  on={allOn}                  partial={!allOn && count > 0}                  reduce={reduce}                />                {count} of {changed.length} selected              </button>              <LayoutGroup id={`${uid}-view`}>                <div                  role="radiogroup"                  aria-label="Diff view"                  className="flex rounded-full bg-(--color-paper-2) p-0.5 shadow-[inset_0_0_0_1px_var(--color-rule)]"                >                  {(["inline", "split"] as const).map((v) => (                    <button                      key={v}                      type="button"                      role="radio"                      aria-checked={view === v}                      onClick={() => setView(v)}                      className={cn(                        "relative h-7 rounded-full px-3 text-[12px] font-medium transition-colors outline-none focus-visible:ring-2 focus-visible:ring-(--color-focus)",                        view === v                          ? "text-(--color-ink)"                          : "text-(--color-neutral) hover:text-(--color-ink-2)",                      )}                    >                      {view === v ? (                        <motion.span                          layoutId="view-pill"                          className="absolute inset-0 rounded-full bg-(--color-paper) shadow-[0_0_0_0.5px_var(--color-rule),0_1px_3px_rgba(0,0,0,0.1)]"                          transition={                            reduce                              ? { duration: 0 }                              : { type: "spring", bounce: 0.2, duration: 0.4 }                          }                        />                      ) : null}                      <span className="relative">                        {v === "inline" ? "Inline" : "Side by side"}                      </span>                    </button>                  ))}                </div>              </LayoutGroup>            </div>          ) : null}
          <div            role="list"            className="flex flex-col border-t border-(--color-rule)"          >            {changed.map((f, i) => {              const on = included.has(f.id);              const isApplied = applied.has(f.id);              return (                <motion.div                  role="listitem"                  key={f.id}                  initial={                    reduce ? false : { opacity: 0, y: 8, filter: "blur(4px)" }                  }                  animate={{ opacity: 1, y: 0, filter: "blur(0px)" }}                  transition={{                    duration: 0.35,                    ease: EASE_OUT,                    delay: reduce ? 0 : 0.05 + i * 0.05,                  }}                  className={cn(                    "flex gap-3 px-5 py-3.5 transition-opacity duration-200 sm:px-6",                    i > 0 && "border-t border-(--color-rule)",                    state === "review" && !on && "opacity-55",                  )}                >                  {state === "review" ? (                    <button                      type="button"                      role="checkbox"                      aria-checked={on}                      aria-label={`Include ${f.label}`}                      onClick={() => toggleField(f.id)}                      className="mt-0.5 h-fit rounded-[6px] outline-none focus-visible:ring-2 focus-visible:ring-(--color-focus)"                    >                      <Check on={on} reduce={reduce} />                    </button>                  ) : null}                  <div className="min-w-0 flex-1">                    <div className="flex items-center gap-2 text-[11.5px] font-medium text-(--color-neutral)">                      {f.label}                      {accepted && !isApplied ? (                        <span className="rounded-full bg-(--color-paper-2) px-1.5 text-[10.5px]">                          kept current                        </span>                      ) : null}                    </div>                    {accepted ? (                      <div className="mt-1 text-[14px] leading-relaxed text-(--color-ink)">                        {isApplied ? (                          <Merged segs={diffs[f.id]} reduce={reduce} />                        ) : (                          f.before || <Empty />                        )}                      </div>                    ) : view === "inline" ? (                      <div className="mt-1 text-[14px] leading-relaxed">                        <Segs                          segs={diffs[f.id]}                          show={["same", "del", "add"]}                        />                      </div>                    ) : (                      <div className="mt-1.5 grid gap-2 sm:grid-cols-2">                        <Side                          label="Current"                          tone="del"                          segs={diffs[f.id]}                          empty={!f.before}                        />                        <Side                          label="Proposed"                          tone="add"                          segs={diffs[f.id]}                          empty={!f.after}                        />                      </div>                    )}                  </div>                </motion.div>              );            })}          </div>
          {unchanged.length ? (            <div className="border-t border-(--color-rule)">              <button                type="button"                aria-expanded={showSame}                onClick={() => setShowSame((v) => !v)}                className="flex w-full items-center gap-2 px-5 py-2.5 text-left text-[12px] text-(--color-neutral) transition-colors outline-none hover:text-(--color-ink-2) focus-visible:ring-2 focus-visible:ring-(--color-focus) focus-visible:ring-inset sm:px-6"              >                <motion.span                  animate={{ rotate: showSame ? 90 : 0 }}                  transition={{ type: "spring", bounce: 0.3, duration: 0.35 }}                  className="flex"                >                  <Icon d="M6 3.5 10.5 8 6 12.5" className="size-3" />                </motion.span>                {unchanged.length} unchanged{" "}                {unchanged.length === 1 ? "field" : "fields"}              </button>              <AnimatePresence initial={false}>                {showSame ? (                  <motion.div                    initial={{ height: 0, opacity: 0 }}                    animate={{ height: "auto", opacity: 1 }}                    exit={{ height: 0, opacity: 0 }}                    transition={                      reduce                        ? { duration: 0 }                        : { height: HEIGHT, opacity: { duration: 0.2 } }                    }                    className="overflow-hidden"                  >                    <div className="flex flex-col gap-2 px-5 pb-3 sm:px-6">                      {unchanged.map((f) => (                        <div                          key={f.id}                          className="flex items-baseline justify-between gap-4 text-[13px]"                        >                          <span className="text-(--color-neutral)">                            {f.label}                          </span>                          <span className="truncate text-(--color-ink-2)">                            {f.before || <Empty />}                          </span>                        </div>                      ))}                    </div>                  </motion.div>                ) : null}              </AnimatePresence>            </div>          ) : null}        </div>      </motion.div>
      <AnimatePresence>        {error ? (          <motion.div            role="alert"            initial={{ opacity: 0, height: 0 }}            animate={{ opacity: 1, height: "auto" }}            exit={{ opacity: 0, height: 0 }}            className="overflow-hidden"          >            <div className="mx-5 mb-3 rounded-[10px] bg-[color-mix(in_oklch,var(--diff-del)_10%,transparent)] px-3 py-2 text-[12.5px] text-(--diff-del) sm:mx-6">              {error}            </div>          </motion.div>        ) : null}      </AnimatePresence>
      {/* Footer */}      <div className="flex flex-wrap items-center justify-between gap-3 border-t border-(--color-rule) bg-(--color-paper-2)/40 px-5 py-3 sm:px-6">        <div className="relative min-w-0 text-[12px] text-(--color-neutral)">          <AnimatePresence initial={false} mode="popLayout">            <motion.div              key={`${state}-${count}`}              initial={{ opacity: 0, y: 6, filter: "blur(3px)" }}              animate={{ opacity: 1, y: 0, filter: "blur(0px)" }}              exit={{ opacity: 0, y: -6, filter: "blur(3px)" }}              transition={{ duration: 0.22, ease: EASE_OUT }}            >              {accepted                ? "Everything else is unchanged."                : rejected                  ? "You can bring the proposal back."                  : state === "review"                    ? count                      ? "Nothing changes until you apply."                      : "Select at least one change."                    : "You’re in control."}            </motion.div>          </AnimatePresence>        </div>        <div className="ml-auto flex items-center gap-1.5">          {state === "compact" ? (            <>              <Button                quiet                onClick={() => {                  setState("rejected");                  onReject?.();                }}                disabled={!changed.length}              >                Dismiss              </Button>              <Button                ref={toggleRef}                aria-expanded={false}                aria-controls={`${uid}-review`}                onClick={() => setState("review")}                disabled={!changed.length}              >                Review changes                <Icon d="M3 8h10M9 4l4 4-4 4" />              </Button>            </>          ) : state === "review" ? (            <>              <Button                ref={toggleRef}                quiet                aria-expanded                aria-controls={`${uid}-review`}                onClick={() => setState("compact")}                disabled={!!pending}              >                Collapse              </Button>              <Button onClick={accept} disabled={!count || !!pending}>                <AnimatePresence initial={false} mode="popLayout">                  <motion.span                    key={pending === "accept" ? "busy" : `n-${count}`}                    initial={{ opacity: 0, y: 8, filter: "blur(3px)" }}                    animate={{ opacity: 1, y: 0, filter: "blur(0px)" }}                    exit={{ opacity: 0, y: -8, filter: "blur(3px)" }}                    transition={{ duration: 0.2 }}                    className="flex items-center gap-1.5 whitespace-nowrap"                  >                    {pending === "accept" ? (                      <>                        <Spinner reduce={reduce} />                        Applying                      </>                    ) : (                      <>                        <Icon d="M3.5 8.5 6.5 11.5 12.5 4.5" />                        {allOn ? "Apply all" : `Apply ${count}`}                      </>                    )}                  </motion.span>                </AnimatePresence>              </Button>            </>          ) : accepted ? (            canUndo ? (              <Button quiet onClick={undo} disabled={!!pending}>                {pending === "undo" ? (                  <Spinner reduce={reduce} />                ) : (                  <Icon d="M3 8a5 5 0 1 0 1.5-3.6M3 2.5v3h3" />                )}                {pending === "undo" ? "Undoing" : "Undo"}              </Button>            ) : null          ) : (            <Button quiet onClick={() => setState("compact")}>              <Icon d="M3 8a5 5 0 1 0 1.5-3.6M3 2.5v3h3" />              Bring it back            </Button>          )}        </div>      </div>      <div className="sr-only" role="status" aria-live="polite">        {pending          ? "Saving."          : accepted            ? `${applied.size} changes applied.`            : rejected              ? "Proposal dismissed."              : state === "review"                ? `Reviewing ${changed.length} changes, ${count} selected.`                : ""}      </div>    </motion.section>  );}
function Segs({ segs, show }: { segs: Seg[]; show: Seg["type"][] }) {  return (    <>      {segs        .filter((s) => show.includes(s.type))        .map((s, i) =>          s.type === "same" ? (            <span key={i}>{s.text}</span>          ) : s.type === "del" ? (            <del              key={i}              className="rounded-[4px] bg-[color-mix(in_oklch,var(--diff-del)_12%,transparent)] px-0.5 text-(--diff-del) decoration-[color-mix(in_oklch,var(--diff-del)_60%,transparent)]"            >              <span className="sr-only">removed: </span>              {s.text}            </del>          ) : (            <ins              key={i}              className="rounded-[4px] bg-[color-mix(in_oklch,var(--diff-add)_14%,transparent)] px-0.5 text-(--diff-add) no-underline"            >              <span className="sr-only">added: </span>              {s.text}            </ins>          ),        )}    </>  );}
function Side({  label,  tone,  segs,  empty,}: {  label: string;  tone: "add" | "del";  segs: Seg[];  empty: boolean;}) {  return (    <div className="rounded-[12px] bg-(--color-paper-2)/60 px-3 py-2 shadow-[inset_0_0_0_1px_var(--color-rule)]">      <div className="mb-0.5 flex items-center gap-1.5 text-[10.5px] font-medium tracking-[0.08em] text-(--color-neutral) uppercase">        <span          className={cn(            "size-1.5 rounded-full",            tone === "add" ? "bg-(--diff-add)" : "bg-(--diff-del)",          )}        />        {label}      </div>      <div className="text-[13.5px] leading-relaxed">        {empty ? <Empty /> : <Segs segs={segs} show={["same", tone]} />}      </div>    </div>  );}
/** After applying: removed words blur away and added words settle into plain text. */function Merged({ segs, reduce }: { segs: Seg[]; reduce: boolean }) {  return (    <>      {segs.map((s, i) =>        s.type === "same" ? (          <span key={i}>{s.text}</span>        ) : s.type === "add" ? (          <motion.span            key={i}            initial={{              backgroundColor:                "color-mix(in oklch, var(--diff-add) 22%, transparent)",            }}            animate={{              backgroundColor:                "color-mix(in oklch, var(--diff-add) 0%, transparent)",            }}            transition={{              duration: reduce ? 0 : 1.4,              delay: reduce ? 0 : 0.5,              ease: "easeOut",            }}            className="rounded-[4px]"          >            {s.text}          </motion.span>        ) : (          <motion.span            key={i}            initial={              reduce                ? { opacity: 0, maxWidth: 0 }                : { opacity: 0.8, filter: "blur(0px)", maxWidth: 400 }            }            animate={{              opacity: 0,              filter: reduce ? "none" : "blur(4px)",              maxWidth: 0,            }}            transition={{ duration: reduce ? 0 : 0.5, ease: EASE_OUT }}            aria-hidden            className="inline-block overflow-hidden align-bottom whitespace-pre text-(--diff-del) line-through"          >            {s.text}          </motion.span>        ),      )}    </>  );}
function Empty() {  return <span className="text-(--color-neutral) italic">Not set</span>;}
function Check({  on,  partial = false,  reduce,}: {  on: boolean;  partial?: boolean;  reduce: boolean;}) {  return (    <span      aria-hidden      className={cn(        "grid size-[18px] place-items-center rounded-[6px] transition-[background-color,box-shadow] duration-200",        on || partial          ? "bg-(--color-ink) text-(--color-paper)"          : "bg-(--color-paper) shadow-[inset_0_0_0_1.5px_var(--color-rule)]",      )}    >      <svg        viewBox="0 0 16 16"        className="size-3"        fill="none"        stroke="currentColor"        strokeWidth="2.4"        strokeLinecap="round"        strokeLinejoin="round"      >        {partial ? (          <path d="M4.5 8h7" />        ) : (          <motion.path            d="M3.5 8.5 6.5 11.5 12.5 4.5"            initial={false}            animate={{ pathLength: on ? 1 : 0, opacity: on ? 1 : 0 }}            transition={{ duration: reduce ? 0 : 0.2 }}          />        )}      </svg>    </span>  );}
function Spinner({ reduce }: { reduce: boolean }) {  return (    <motion.svg      viewBox="0 0 16 16"      className="size-3.5"      fill="none"      stroke="currentColor"      strokeWidth="2"      strokeLinecap="round"      animate={reduce ? undefined : { rotate: 360 }}      transition={{ duration: 0.8, repeat: Infinity, ease: "linear" }}    >      <path d="M8 2a6 6 0 1 1-6 6" />    </motion.svg>  );}
function Button({  quiet,  children,  ref,  ...rest}: {  quiet?: boolean;  ref?: Ref<HTMLButtonElement>;} & ButtonHTMLAttributes<HTMLButtonElement>) {  return (    <button      ref={ref}      type="button"      {...rest}      className={cn(        "inline-flex h-9 items-center gap-1.5 overflow-hidden rounded-full px-3.5 text-[12.5px] font-medium transition-[background-color,color,opacity,transform] duration-150 outline-none active:scale-[0.97] disabled:pointer-events-none disabled:opacity-40",        "focus-visible:ring-2 focus-visible:ring-(--color-focus) focus-visible:ring-offset-2 focus-visible:ring-offset-(--color-paper)",        quiet          ? "text-(--color-ink-2) hover:bg-(--color-paper-2) hover:text-(--color-ink)"          : "bg-(--color-ink) text-(--color-paper) hover:opacity-90",      )}    >      {children}    </button>  );}

Adjust import paths according to your folder structure.

Basic Usage

tsx
import { DiffApprovalCard } from "@/components/ui/diff-approval-card";
<DiffApprovalCard  title="Storefront details"  fields={[    { id: "headline", label: "Headline", before: "Objects for everyday life.", after: "Everyday objects, considered design." },    { id: "shipping", label: "Shipping", before: "Ships in 5–7 business days", after: "Ships in 2–3 business days" },  ]}  onAccept={(result) => api.saveStore(result)}  onUndo={(result) => api.revertStore(result)}/>

Props

PropTypeRequiredDefaultDescription
fields{ id, label, before, after }[]Yes—Fields to compare. Identical ones are grouped as unchanged.
title / descriptionstringNo—Heading and subline.
defaultExpandedbooleanNofalseStart in review.
defaultView"inline" | "split"No"inline"Inline diff or side by side.
onAccept(fields) => void | Promise<void>No—Receives every field with after set to the value that will be current. A rejection keeps the card in review and shows an error.
onUndo(fields) => void | Promise<void>No—Rolls back. Undo shows when this is set, or when there is no onAccept.
onReject() => voidNo—Called when the proposal is dismissed.
classNamestringNo—Classes for the card.

Best Practices

  1. Resolve onAccept only after the save succeeds; the card waits and shows an error if it rejects.
  2. Use inline view for short text and side by side for longer values or when the order of words changed a lot.
  3. Keep labels human (“Return policy”, not returns_policy); they're also the checkbox names for screen readers.
  4. Escape collapses the review, and every state change is announced.