<?php
/**
 * Plugin settings: one option, defaults and sanitizing.
 *
 * @package Dialtidy
 */

namespace Dialtidy;

defined( 'ABSPATH' ) || exit;

/**
 * Settings.
 */
class Settings {

	const OPTION = 'dialtidy_settings';

	/** Allowed values of the country source of a phone field. */
	const SOURCES = array( 'all', 'selling', 'shipping', 'custom' );

	/** Allowed checking modes. */
	const MODES = array( 'block', 'warn', 'off' );

	/** Phone fields. */
	const GROUPS = array( 'billing', 'shipping' );

	/**
	 * Cached settings.
	 *
	 * @var array<string,mixed>|null
	 */
	private static $cache = null;

	/**
	 * Defaults.
	 *
	 * @return array<string,mixed>
	 */
	public static function defaults() {
		return array(
			'billing_source'   => 'all',
			'billing_custom'   => array(),
			'billing_exclude'  => array(),
			'shipping_source'  => 'all',
			'shipping_custom'  => array(),
			'shipping_exclude' => array(),
			'popular'          => array(),
			'mode'             => 'block',
		);
	}

	/**
	 * All settings, defaults filled in.
	 *
	 * @return array<string,mixed>
	 */
	public static function all() {
		if ( null !== self::$cache ) {
			return self::$cache;
		}
		$stored = get_option( self::OPTION, array() );
		$all    = self::sanitize( is_array( $stored ) ? $stored : array() );
		if ( Countries::all_codes() ) {
			self::$cache = $all;
		}
		return $all;
	}

	/**
	 * One setting.
	 *
	 * @param string $key Key.
	 * @return mixed
	 */
	public static function get( $key ) {
		$all = self::all();
		return array_key_exists( $key, $all ) ? $all[ $key ] : null;
	}

	/**
	 * Saves settings (sanitized).
	 *
	 * @param array<string,mixed> $values Values.
	 */
	public static function update( array $values ) {
		update_option( self::OPTION, self::sanitize( array_merge( self::all(), $values ) ), true );
		self::$cache = null;
	}

	/**
	 * Forgets the cached settings.
	 */
	public static function reset() {
		self::$cache = null;
	}

	/**
	 * Keeps known keys and allowed values only.
	 *
	 * @param array<string,mixed> $raw Raw values.
	 * @return array<string,mixed>
	 */
	public static function sanitize( array $raw ) {
		$out = self::defaults();
		foreach ( self::GROUPS as $group ) {
			$source = isset( $raw[ $group . '_source' ] ) ? (string) $raw[ $group . '_source' ] : '';
			if ( in_array( $source, self::SOURCES, true ) ) {
				$out[ $group . '_source' ] = $source;
			}
			$out[ $group . '_custom' ]  = self::codes( isset( $raw[ $group . '_custom' ] ) ? $raw[ $group . '_custom' ] : array() );
			$out[ $group . '_exclude' ] = self::codes( isset( $raw[ $group . '_exclude' ] ) ? $raw[ $group . '_exclude' ] : array() );
		}
		$out['popular'] = array_slice( self::codes( isset( $raw['popular'] ) ? $raw['popular'] : array() ), 0, 20 );
		$mode           = isset( $raw['mode'] ) ? (string) $raw['mode'] : '';
		if ( in_array( $mode, self::MODES, true ) ) {
			$out['mode'] = $mode;
		}
		return $out;
	}

	/**
	 * Country codes that WooCommerce knows (any two letters before WooCommerce has loaded its countries), upper case, unique.
	 *
	 * @param mixed $raw Raw list.
	 * @return array<int,string>
	 */
	public static function codes( $raw ) {
		if ( ! is_array( $raw ) ) {
			return array();
		}
		$known = Countries::all_codes();
		$out   = array();
		foreach ( array_slice( $raw, 0, 300 ) as $code ) {
			$code = is_string( $code ) ? strtoupper( trim( $code ) ) : '';
			$ok   = $known ? isset( $known[ $code ] ) : (bool) preg_match( '/^[A-Z]{2}$/', $code );
			if ( $ok && ! in_array( $code, $out, true ) ) {
				$out[] = $code;
			}
		}
		return $out;
	}
}