<?php
/**
 * Countries a phone field accepts.
 *
 * @package Dialtidy
 */

namespace Dialtidy;

defined( 'ABSPATH' ) || exit;

/**
 * Countries.
 */
class Countries {

	/**
	 * Every country WooCommerce knows: code => name.
	 *
	 * @return array<string,string>
	 */
	public static function all_codes() {
		if ( ! function_exists( 'WC' ) || ! WC()->countries ) {
			return array();
		}
		return (array) WC()->countries->get_countries();
	}

	/**
	 * Countries a phone field never accepts.
	 *
	 * @param string $group billing or shipping.
	 * @return array<int,string> Upper-case codes.
	 */
	public static function excluded( $group ) {
		return array_map( 'strval', (array) Settings::get( ( 'shipping' === $group ? 'shipping' : 'billing' ) . '_exclude' ) );
	}

	/**
	 * Countries a phone field is limited to (excluded removed); null when not limited or when the limit leaves no country.
	 *
	 * @param string $group billing or shipping.
	 * @return array<int,string>|null Upper-case codes.
	 */
	public static function only( $group ) {
		$group  = 'shipping' === $group ? 'shipping' : 'billing';
		$source = (string) Settings::get( $group . '_source' );
		$list   = array();
		if ( 'selling' === $source && function_exists( 'WC' ) && WC()->countries ) {
			$list = array_keys( (array) WC()->countries->get_allowed_countries() );
		} elseif ( 'shipping' === $source && function_exists( 'WC' ) && WC()->countries ) {
			$list = array_keys( (array) WC()->countries->get_shipping_countries() );
		} elseif ( 'custom' === $source ) {
			$list = (array) Settings::get( $group . '_custom' );
		}
		$list = array_values( array_diff( array_map( 'strtoupper', array_map( 'strval', $list ) ), self::excluded( $group ) ) );
		return $list ? $list : null;
	}

	/**
	 * Whether a field is set to a country list that leaves no country (then only the excluded ones are refused).
	 *
	 * @param string $group billing or shipping.
	 * @return bool
	 */
	public static function limit_is_empty( $group ) {
		$group = 'shipping' === $group ? 'shipping' : 'billing';
		return 'all' !== Settings::get( $group . '_source' ) && null === self::only( $group );
	}

	/**
	 * Countries shown in a phone field's list; an empty list means every country.
	 *
	 * @param string $group billing or shipping.
	 * @return array<int,string> Upper-case codes.
	 */
	public static function allowed( $group ) {
		$only = self::only( $group );
		if ( null !== $only ) {
			return $only;
		}
		$exclude = self::excluded( $group );
		return $exclude ? array_values( array_diff( array_keys( self::all_codes() ), $exclude ) ) : array();
	}

	/**
	 * Whether a phone field accepts numbers from a country.
	 *
	 * @param string $group   billing or shipping.
	 * @param string $country Upper-case code.
	 * @return bool
	 */
	public static function accepts( $group, $country ) {
		$country = strtoupper( (string) $country );
		$only    = self::only( $group );
		if ( null !== $only && ! in_array( $country, $only, true ) ) {
			return false;
		}
		return ! in_array( $country, self::excluded( $group ), true );
	}

	/**
	 * The store's own country.
	 *
	 * @return string Upper-case code or ''.
	 */
	public static function store() {
		if ( ! function_exists( 'WC' ) || ! WC()->countries ) {
			return '';
		}
		return strtoupper( (string) WC()->countries->get_base_country() );
	}
}