<?php
/**
 * Business customer identifiers at checkout (SIRET and VAT number).
 *
 * Both checkout types are supported:
 * - Block checkout (default since WooCommerce 8.3) through the Additional Checkout Fields API.
 * - Classic shortcode checkout through the woocommerce_checkout_fields filter.
 *
 * The fields are optional: an order with a SIRET is treated as B2B, an order
 * without one as B2C (to be e-reported, not e-invoiced).
 *
 * @package EFactureFR
 */

defined( 'ABSPATH' ) || exit;

/**
 * Checkout fields.
 */
class EFacture_FR_Checkout_Fields {

	const BLOCK_SIRET = 'efacture-fr/siret';
	const BLOCK_VAT   = 'efacture-fr/vat-number';

	// Meta keys used by the Additional Checkout Fields API for the "order" location.
	const BLOCK_META_SIRET = '_wc_other/efacture-fr/siret';
	const BLOCK_META_VAT   = '_wc_other/efacture-fr/vat-number';

	// Meta keys used by the classic checkout.
	const CLASSIC_META_SIRET = '_billing_efacture_siret';
	const CLASSIC_META_VAT   = '_billing_efacture_vat';

	/**
	 * Hook in.
	 */
	public static function init() {
		add_action( 'woocommerce_init', array( __CLASS__, 'register_block_fields' ) );

		add_filter( 'woocommerce_checkout_fields', array( __CLASS__, 'add_classic_fields' ) );
		add_action( 'woocommerce_after_checkout_validation', array( __CLASS__, 'validate_classic' ), 10, 2 );
		add_action( 'woocommerce_checkout_create_order', array( __CLASS__, 'save_classic' ), 10, 2 );
	}

	/**
	 * Register fields for the block checkout.
	 */
	public static function register_block_fields() {
		if ( ! function_exists( 'woocommerce_register_additional_checkout_field' ) ) {
			return;
		}

		woocommerce_register_additional_checkout_field(
			array(
				'id'                => self::BLOCK_SIRET,
				'label'             => __( 'SIRET (businesses only)', 'factella' ),
				'optionalLabel'     => __( 'SIRET (businesses only, optional)', 'factella' ),
				'location'          => 'order',
				'type'              => 'text',
				'required'          => false,
				'sanitize_callback' => array( 'EFacture_FR_Identifiers', 'normalize' ),
				'validate_callback' => static function ( $value ) {
					if ( '' !== $value && ! EFacture_FR_Identifiers::is_valid_siret( $value ) ) {
						return new WP_Error( 'efacture_fr_invalid_siret', __( 'The SIRET number is not valid. Please check the 14 digits.', 'factella' ) );
					}
					return true;
				},
			)
		);

		woocommerce_register_additional_checkout_field(
			array(
				'id'                => self::BLOCK_VAT,
				'label'             => __( 'VAT number (businesses only)', 'factella' ),
				'optionalLabel'     => __( 'VAT number (businesses only, optional)', 'factella' ),
				'location'          => 'order',
				'type'              => 'text',
				'required'          => false,
				'sanitize_callback' => array( 'EFacture_FR_Identifiers', 'normalize' ),
				'validate_callback' => static function ( $value ) {
					if ( '' !== $value && ! EFacture_FR_Identifiers::looks_like_eu_vat( $value ) ) {
						return new WP_Error( 'efacture_fr_invalid_vat', __( 'The VAT number is not valid.', 'factella' ) );
					}
					return true;
				},
			)
		);
	}

	/**
	 * Add fields to the classic checkout.
	 *
	 * @param array $fields Checkout fields.
	 * @return array
	 */
	public static function add_classic_fields( $fields ) {
		$fields['billing']['billing_efacture_siret'] = array(
			'label'    => __( 'SIRET (businesses only)', 'factella' ),
			'required' => false,
			'class'    => array( 'form-row-first' ),
			'priority' => 35,
		);
		$fields['billing']['billing_efacture_vat'] = array(
			'label'    => __( 'VAT number (businesses only)', 'factella' ),
			'required' => false,
			'class'    => array( 'form-row-last' ),
			'priority' => 36,
		);
		return $fields;
	}

	/**
	 * Validate classic checkout values.
	 *
	 * @param array    $data   Posted data.
	 * @param WP_Error $errors Errors.
	 */
	public static function validate_classic( $data, $errors ) {
		$siret = isset( $data['billing_efacture_siret'] ) ? EFacture_FR_Identifiers::normalize( $data['billing_efacture_siret'] ) : '';
		$vat   = isset( $data['billing_efacture_vat'] ) ? EFacture_FR_Identifiers::normalize( $data['billing_efacture_vat'] ) : '';

		if ( '' !== $siret && ! EFacture_FR_Identifiers::is_valid_siret( $siret ) ) {
			$errors->add( 'efacture_fr_invalid_siret', __( 'The SIRET number is not valid. Please check the 14 digits.', 'factella' ) );
		}
		if ( '' !== $vat && ! EFacture_FR_Identifiers::looks_like_eu_vat( $vat ) ) {
			$errors->add( 'efacture_fr_invalid_vat', __( 'The VAT number is not valid.', 'factella' ) );
		}
	}

	/**
	 * Store classic checkout values on the order.
	 *
	 * @param WC_Order $order Order being created.
	 * @param array    $data  Posted data.
	 */
	public static function save_classic( $order, $data ) {
		if ( ! empty( $data['billing_efacture_siret'] ) ) {
			$order->update_meta_data( self::CLASSIC_META_SIRET, EFacture_FR_Identifiers::normalize( $data['billing_efacture_siret'] ) );
		}
		if ( ! empty( $data['billing_efacture_vat'] ) ) {
			$order->update_meta_data( self::CLASSIC_META_VAT, EFacture_FR_Identifiers::normalize( $data['billing_efacture_vat'] ) );
		}
	}

	/**
	 * Read the buyer identifiers from an order, whichever checkout was used.
	 *
	 * @param WC_Order $order Order.
	 * @return array{siret:string,siren:string,vat:string}
	 */
	public static function get_buyer_ids( $order ) {
		$siret = (string) $order->get_meta( self::BLOCK_META_SIRET );
		if ( '' === $siret ) {
			$siret = (string) $order->get_meta( self::CLASSIC_META_SIRET );
		}
		$vat = (string) $order->get_meta( self::BLOCK_META_VAT );
		if ( '' === $vat ) {
			$vat = (string) $order->get_meta( self::CLASSIC_META_VAT );
		}
		return array(
			'siret' => $siret,
			'siren' => '' !== $siret ? EFacture_FR_Identifiers::siren_from_siret( $siret ) : '',
			'vat'   => $vat,
		);
	}
}