/**
 * External dependencies
 */
import { __ } from '@wordpress/i18n';
import { useState } from '@wordpress/element';
import Button from '@woocommerce/base-components/button';
import LoadingMask from '@woocommerce/base-components/loading-mask';
import { withInstanceId } from '@wordpress/compose';
import {
	ValidatedTextInput,
	ValidationInputError,
} from '@woocommerce/blocks-checkout';
import { useSelect } from '@wordpress/data';
import { VALIDATION_STORE_KEY } from '@woocommerce/block-data';
import classnames from 'classnames';

/**
 * Internal dependencies
 */
import './style.scss';

export interface TotalsCouponProps {
	/**
	 * Instance id of the input
	 */
	instanceId: string;
	/**
	 * Whether the component is in a loading state
	 */
	isLoading?: boolean;
	/**
	 * Whether the coupon form is hidden
	 */
	displayCouponForm?: boolean;
	/**
	 * Submit handler
	 */
	onSubmit?: ( couponValue: string ) => Promise< boolean > | undefined;
}

export const TotalsCoupon = ( {
	instanceId,
	isLoading = false,
	onSubmit,
	displayCouponForm = false,
}: TotalsCouponProps ): JSX.Element => {
	const [ couponValue, setCouponValue ] = useState( '' );
	const [ isCouponFormHidden, setIsCouponFormHidden ] = useState(
		! displayCouponForm
	);
	const textInputId = `wc-block-components-totals-coupon__input-${ instanceId }`;
	const formWrapperClass = classnames(
		'wc-block-components-totals-coupon__content',
		{
			'screen-reader-text': isCouponFormHidden,
		}
	);
	const { validationErrorId } = useSelect( ( select ) => {
		const store = select( VALIDATION_STORE_KEY );
		return {
			validationErrorId: store.getValidationErrorId( textInputId ),
		};
	} );
	const handleCouponAnchorClick = (
		e: React.MouseEvent< HTMLAnchorElement, MouseEvent >
	) => {
		e.preventDefault();
		setIsCouponFormHidden( false );
	};
	const handleCouponSubmit = (
		e: React.MouseEvent< HTMLButtonElement, MouseEvent >
	) => {
		e.preventDefault();
		if ( onSubmit !== undefined ) {
			onSubmit( couponValue ).then( ( result ) => {
				if ( result ) {
					setCouponValue( '' );
					setIsCouponFormHidden( true );
				}
			} );
		} else {
			setCouponValue( '' );
			setIsCouponFormHidden( true );
		}
	};

	return (
		<div className="wc-block-components-totals-coupon">
			{ isCouponFormHidden && (
				<a
					role="button"
					href="#wc-block-components-totals-coupon__form"
					className="wc-block-components-totals-coupon-link"
					aria-label={ __(
						'Add a coupon',
						'woo-gutenberg-products-block'
					) }
					onClick={ handleCouponAnchorClick }
				>
					{ __( 'Add a coupon', 'woo-gutenberg-products-block' ) }
				</a>
			) }
			<LoadingMask
				screenReaderLabel={ __(
					'Applying coupon…',
					'woo-gutenberg-products-block'
				) }
				isLoading={ isLoading }
				showSpinner={ false }
			>
				<div className={ formWrapperClass }>
					<form
						className="wc-block-components-totals-coupon__form"
						id="wc-block-components-totals-coupon__form"
					>
						<ValidatedTextInput
							id={ textInputId }
							errorId="coupon"
							className="wc-block-components-totals-coupon__input"
							label={ __(
								'Enter code',
								'woo-gutenberg-products-block'
							) }
							value={ couponValue }
							ariaDescribedBy={ validationErrorId }
							onChange={ ( newCouponValue ) => {
								setCouponValue( newCouponValue );
							} }
							focusOnMount={ true }
							showError={ false }
						/>
						<Button
							className="wc-block-components-totals-coupon__button"
							disabled={ isLoading || ! couponValue }
							showSpinner={ isLoading }
							onClick={ handleCouponSubmit }
							type="submit"
						>
							{ __( 'Apply', 'woo-gutenberg-products-block' ) }
						</Button>
					</form>
					<ValidationInputError
						propertyName="coupon"
						elementId={ textInputId }
					/>
				</div>
			</LoadingMask>
		</div>
	);
};

export default withInstanceId( TotalsCoupon );