Textarea With Counter

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import type { ChangeEvent, ReactNode, TextareaHTMLAttributes } from "react";
import { useId, useState } from "react";

function cx(...parts: Array<string | false | null | undefined>): string {
  return parts.filter(Boolean).join(" ");
}

const TEXTAREA_BASE =
  "w-full min-h-[80px] resize-y rounded-[var(--ds-radius-sm)] border bg-[var(--ds-color-input)] px-3 py-2 text-sm leading-5 text-[var(--ds-color-foreground)] shadow-none transition-colors duration-150 ease-out placeholder:text-[var(--ds-color-muted-foreground)] hover:bg-[var(--ds-color-input-hover,var(--ds-color-input))] focus:bg-[var(--ds-color-input-focus,var(--ds-color-input))] focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-[var(--ds-color-focus-ring)] disabled:pointer-events-none disabled:bg-[var(--ds-color-muted)] disabled:text-[var(--ds-color-muted-foreground)] disabled:opacity-60 read-only:bg-[var(--ds-color-surface-subtle)] read-only:text-[var(--ds-color-muted-foreground)] motion-reduce:transition-none";

const TEXTAREA_BORDER =
  "border-[var(--ds-color-border)] focus:border-[var(--ds-color-border-strong)]";

export interface TextareaWithCounterProps extends TextareaHTMLAttributes<HTMLTextAreaElement> {
  /** Visible label — required. */
  label: ReactNode;
  /** Optional helper text rendered beside the counter. */
  helperText?: ReactNode;
}

/**
 * Textarea with a live character counter. The count is derived from the
 * real value — the controlled `value` when provided, otherwise the
 * uncontrolled text the user has typed — so it always reflects what is
 * actually in the field. When `maxLength` is supplied the counter shows
 * `current / maximum` and the native attribute enforces the limit; at the
 * limit the count gains emphasis (weight + foreground color — no loud
 * colors or animation). When no `maxLength` is supplied the counter shows
 * a plain character count. The counter region is `aria-live` polite and
 * linked with `aria-describedby`.
 */
export function TextareaWithCounter({
  label,
  helperText,
  id,
  className,
  rows = 3,
  value,
  defaultValue = "",
  onChange,
  maxLength,
  ...props
}: TextareaWithCounterProps) {
  const generatedId = useId();
  const textareaId = id ?? `textarea-${generatedId}`;
  const countId = `${textareaId}-count`;
  const [internalValue, setInternalValue] = useState(String(defaultValue ?? ""));
  const currentValue = value === undefined ? internalValue : String(value ?? "");
  const atLimit = maxLength !== undefined && currentValue.length >= maxLength;

  function handleChange(event: ChangeEvent<HTMLTextAreaElement>) {
    if (value === undefined) setInternalValue(event.target.value);
    onChange?.(event);
  }

  return (
    <div className="w-full">
      <label
        htmlFor={textareaId}
        className="mb-2 block text-[13px] font-medium leading-5 text-[var(--ds-color-foreground)]"
      >
        {label}
      </label>
      <textarea
        id={textareaId}
        rows={rows}
        value={currentValue}
        onChange={handleChange}
        maxLength={maxLength}
        aria-describedby={countId}
        className={cx(TEXTAREA_BASE, TEXTAREA_BORDER, className)}
        {...props}
      />
      <div
        id={countId}
        aria-live="polite"
        className="mt-2 flex items-baseline justify-between gap-3 text-xs leading-4 text-[var(--ds-color-muted-foreground)]"
      >
        <span>{helperText}</span>
        <span className={cx("shrink-0", atLimit && "font-medium text-[var(--ds-color-foreground)]")}>
          {currentValue.length}{maxLength !== undefined ? ` / ${maxLength}` : ""}
        </span>
      </div>
    </div>
  );
}

export default TextareaWithCounter;

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/* DevSnips React — JavaScript parity build.
 * Same API, behavior, and classes as code.tsx; TypeScript types removed.
 * Regenerated from code.tsx — edit code.tsx and re-run the generator.
 */

import { useId, useState } from "react";
function cx(...parts) {
  return parts.filter(Boolean).join(" ");
}
const TEXTAREA_BASE = "w-full min-h-[80px] resize-y rounded-[var(--ds-radius-sm)] border bg-[var(--ds-color-input)] px-3 py-2 text-sm leading-5 text-[var(--ds-color-foreground)] shadow-none transition-colors duration-150 ease-out placeholder:text-[var(--ds-color-muted-foreground)] hover:bg-[var(--ds-color-input-hover,var(--ds-color-input))] focus:bg-[var(--ds-color-input-focus,var(--ds-color-input))] focus-visible:outline-2 focus-visible:outline-offset-2 focus-visible:outline-[var(--ds-color-focus-ring)] disabled:pointer-events-none disabled:bg-[var(--ds-color-muted)] disabled:text-[var(--ds-color-muted-foreground)] disabled:opacity-60 read-only:bg-[var(--ds-color-surface-subtle)] read-only:text-[var(--ds-color-muted-foreground)] motion-reduce:transition-none";
const TEXTAREA_BORDER = "border-[var(--ds-color-border)] focus:border-[var(--ds-color-border-strong)]";
export function TextareaWithCounter({
  label,
  helperText,
  id,
  className,
  rows = 3,
  value,
  defaultValue = "",
  onChange,
  maxLength,
  ...props
}) {
  const generatedId = useId();
  const textareaId = id ?? `textarea-${generatedId}`;
  const countId = `${textareaId}-count`;
  const [internalValue, setInternalValue] = useState(String(defaultValue ?? ""));
  const currentValue = value === undefined ? internalValue : String(value ?? "");
  const atLimit = maxLength !== undefined && currentValue.length >= maxLength;
  function handleChange(event) {
    if (value === undefined) setInternalValue(event.target.value);
    onChange?.(event);
  }
  return <div className="w-full">
      <label
    htmlFor={textareaId}
    className="mb-2 block text-[13px] font-medium leading-5 text-[var(--ds-color-foreground)]"
  >
        {label}
      </label>
      <textarea
    id={textareaId}
    rows={rows}
    value={currentValue}
    onChange={handleChange}
    maxLength={maxLength}
    aria-describedby={countId}
    className={cx(TEXTAREA_BASE, TEXTAREA_BORDER, className)}
    {...props}
  />
      <div
    id={countId}
    aria-live="polite"
    className="mt-2 flex items-baseline justify-between gap-3 text-xs leading-4 text-[var(--ds-color-muted-foreground)]"
  >
        <span>{helperText}</span>
        <span className={cx("shrink-0", atLimit && "font-medium text-[var(--ds-color-foreground)]")}>
          {currentValue.length}{maxLength !== undefined ? ` / ${maxLength}` : ""}
        </span>
      </div>
    </div>;
}

export default TextareaWithCounter;

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# Textarea With Counter

Textarea with a live character counter (current / maximum) derived from the real value.

## Usage

```tsx
<TextareaWithCounter label="Release notes" maxLength={280} helperText="Shown on the changelog page." rows={4} />
```

## JavaScript

A `code.jsx` build is provided for projects that ship plain JSX. It exposes the same API and behavior as `code.tsx` — only the TypeScript types are removed.

```jsx
<TextareaWithCounter label="Release notes" maxLength={280} helperText="Shown on the changelog page." rows={4} />
```

## Props

| Name | Type | Default | Description |
|---|---|---:|---|
| `label` | `ReactNode` (required) | — | Visible label above the control. |
| `value` / `defaultValue` | `string` | — | Controlled / uncontrolled value. |
| `onChange` | `(event) => void` | — | Native change callback. |
| `rows` | `number` | `3` | Visible rows — the natural height floor (with `min-h-[80px]`). |
| `placeholder` | `string` | — | Muted placeholder (never critical information). |
| `disabled` | `boolean` | — | Native disabled — not focusable, not submitted. |
| `readOnly` | `boolean` | — | Native read-only — focusable, selectable, submitted. |
| `required` / `name` / `id` | `boolean` / `string` | — | Native form semantics (`id` also the label `htmlFor`). |
| `minLength` / `maxLength` | `number` | — | Native length constraints. |
| `className` | `string` | — | Extra Tailwind classes merged onto the control. |
| other native props / `aria-*` | — | — | Passed through to the `<textarea>`. |
| `helperText` | `ReactNode` | — | Optional text beside the counter. |

## States

Native textarea with a live character counter under the field. The count is computed from the actual value (controlled `value` or tracked uncontrolled text) — it updates on every keystroke and is never faked. When `maxLength` is supplied the counter reads `current / maximum` and the native attribute enforces the limit; at the limit the count gains weight + foreground color as a quiet, non-color-only cue. Without `maxLength` the counter is a plain character count.

## Accessibility

The counter region is linked with `aria-describedby` and marked `aria-live="polite"`, so screen readers can read the count on demand and hear polite updates without focus theft. The at-limit cue is text weight + color together — not color alone. Native `maxLength` behavior (typing stops at the cap) is preserved.

## Styling

Built with React, Tailwind CSS, and DevSnips design tokens. The component consumes the `--ds-*` semantic tokens via arbitrary values (for example `bg-[var(--ds-color-input)]`). Define the tokens once in your theme — no component-specific CSS file is required.

## Design Tokens

See [React/DESIGN_TOKENS.md](../../../DESIGN_TOKENS.md) for the authoritative token specification. This textarea uses the semantic color, radius, spacing, and motion tokens.

## Notes

Use for bounded content: changelog entries, status updates, short bios. For long-form content where a limit would be hostile, drop `maxLength` and keep the plain count, or use the plain `textarea`.