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

namespace Streetfill;

defined( 'ABSPATH' ) || exit;

/**
 * Settings.
 */
class Settings {

	const OPTION = 'streetfill_settings';

	/** Address services: setting value => key setting. */
	const SERVICES = array(
		'google'   => 'api_key',
		'geoapify' => 'geoapify_key',
		'here'     => 'here_key',
	);

	/**
	 * Service names, not translated. Here (not in Admin) because add-ons need them outside the admin too.
	 *
	 * @return array<string,string>
	 */
	public static function service_names() {
		return array(
			'google'   => 'Google Maps',
			'geoapify' => 'Geoapify',
			'here'     => 'HERE',
		);
	}

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

	/**
	 * Defaults.
	 *
	 * @return array<string,mixed>
	 */
	public static function defaults() {
		return array(
			'provider'     => 'google',
			'api_key'      => '',
			'geoapify_key' => '',
			'here_key'     => '',
			'style'        => 'on',
		);
	}

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

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

	/**
	 * Forgets the cache (after saving, on switch_blog).
	 */
	public static function reset() {
		self::$cache = null;
	}

	/**
	 * Saves sanitized settings.
	 *
	 * @param array<string,mixed> $values New values.
	 */
	public static function save( array $values ) {
		update_option( self::OPTION, self::sanitize( $values ), true );
		self::reset();
	}

	/**
	 * Cleans settings: unknown keys dropped, every value to its type.
	 *
	 * @param array<string,mixed> $values Raw values.
	 * @return array<string,mixed>
	 */
	public static function sanitize( array $values ) {
		$clean = self::defaults();

		if ( isset( $values['provider'] ) && is_string( $values['provider'] ) && isset( self::SERVICES[ $values['provider'] ] ) ) {
			$clean['provider'] = $values['provider'];
		}
		foreach ( self::SERVICES as $field ) {
			if ( isset( $values[ $field ] ) && is_string( $values[ $field ] ) ) {
				$clean[ $field ] = self::clean_key( $values[ $field ] );
			}
		}
		if ( isset( $values['style'] ) && in_array( $values['style'], array( 'on', 'off' ), true ) ) {
			$clean['style'] = $values['style'];
		}

		return $clean;
	}

	/**
	 * An API key: letters, digits, "-" and "_", at most 100 characters.
	 *
	 * @param string $key Raw key.
	 * @return string
	 */
	public static function clean_key( $key ) {
		$key = preg_replace( '/[^A-Za-z0-9_\-]/', '', trim( $key ) );
		return substr( (string) $key, 0, 100 );
	}

	/**
	 * The chosen address service.
	 *
	 * @return string google, geoapify or here.
	 */
	public static function service() {
		return (string) self::get( 'provider' );
	}

	/**
	 * The key of the chosen service.
	 *
	 * @return string
	 */
	public static function key() {
		return (string) self::get( self::SERVICES[ self::service() ] );
	}

	/**
	 * Whether the chosen service has a key.
	 *
	 * @return bool
	 */
	public static function has_key() {
		return '' !== self::key();
	}
}