wp-calypso/client/my-sites/checkout/src/components/coupon.tsx

import { Button } from '@automattic/composite-checkout';
import { Field, styled, joinClasses } from '@automattic/wpcom-checkout';
import { keyframes } from '@emotion/react';
import { useTranslate } from 'i18n-calypso';
import PropTypes from 'prop-types';
import type { CouponFieldStateProps } from '../hooks/use-coupon-field-state';
import type { CouponStatus } from '@automattic/shopping-cart';

/* eslint-disable @typescript-eslint/no-use-before-define */

export default function Coupon( {
	id,
	className,
	disabled,
	couponStatus,
	couponFieldStateProps,
}: {
	id: string;
	className?: string;
	disabled?: boolean;
	couponStatus: CouponStatus;
	couponFieldStateProps: CouponFieldStateProps;
} ) {
	const translate = useTranslate();
	const {
		couponFieldValue,
		setCouponFieldValue,
		isApplyButtonActive,
		isFreshOrEdited,
		setIsFreshOrEdited,
		handleCouponSubmit,
	} = couponFieldStateProps;

	const hasCouponError = couponStatus === 'rejected';
	const isPending = couponStatus === 'pending';

	const errorMessage = getCouponErrorMessageFromStatus( translate, couponStatus, isFreshOrEdited );

	return (
		<CouponWrapper
			className={ joinClasses( [ className, 'coupon' ] ) }
			onSubmit={ ( event ) => {
				event.preventDefault();
				setIsFreshOrEdited( false );
				handleCouponSubmit();
			} }
		>
			<Field
				id={ id }
				inputClassName="coupon-code"
				value={ couponFieldValue }
				disabled={ disabled || isPending }
				placeholder={ String( translate( 'Enter your coupon code' ) ) }
				isError={ hasCouponError && ! isFreshOrEdited }
				errorMessage={ errorMessage }
				onChange={ ( input ) => {
					setIsFreshOrEdited( true );
					setCouponFieldValue( input );
				} }
			/>

			{ isApplyButtonActive && (
				<ApplyButton disabled={ isPending } buttonType="secondary">
					{ isPending ? translate( 'Processing…' ) : translate( 'Apply' ) }
				</ApplyButton>
			) }
		</CouponWrapper>
	);
}

Coupon.propTypes = {
	id: PropTypes.string.isRequired,
	couponAdded: PropTypes.func,
	disabled: PropTypes.bool,
};

const animateIn = keyframes`
  from {
    opacity: 0;
    transform: translateX(8px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
`;

const animateInRTL = keyframes`
  from {
    opacity: 0;
    transform: translateX(-8px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
`;

const CouponWrapper = styled.form`
	margin: 0;
	padding-top: 0;
	position: relative;

	& input {
		font-size: 14px;
	}
`;

const ApplyButton = styled( Button )`
	animation: ${ animateIn } 0.2s ease-out;
	animation-fill-mode: backwards;
	margin: 0;
	position: absolute;
	font-size: 14px;
	padding: 8px;
	top: 2px;
	right: 2px;

	.rtl & {
		animation-name: ${ animateInRTL };
		left: 4px;
		right: auto;
	}
`;

function getCouponErrorMessageFromStatus(
	translate: ReturnType< typeof useTranslate >,
	status: CouponStatus,
	isFreshOrEdited: boolean
): string | undefined {
	if ( status === 'rejected' && ! isFreshOrEdited ) {
		return translate( 'There was a problem applying this coupon.', { textOnly: true } );
	}
	return undefined;
}