<?php
/**
 * Plugin settings.
 *
 * @package Transtrix
 */

namespace Transtrix;

use Transtrix\Import\Conflict_Resolver;
use Transtrix\Runner\Job_Store;

defined( 'ABSPATH' ) || exit;

/**
 * One place that reads and writes the settings option.
 *
 * The package directory is reported but not settable: a client-supplied path is
 * a traversal foot-gun, and no user has ever needed their packages somewhere
 * else badly enough to earn that risk.
 */
class Settings {

	/**
	 * Option name.
	 */
	const OPTION = 'transtrix_settings';

	/**
	 * Capabilities an administrator may choose between.
	 */
	const CAPABILITIES = array( 'manage_options', 'edit_others_posts' );

	/**
	 * Defaults, taken from the prototype's settings screen.
	 *
	 * @return array<string,mixed>
	 */
	public static function defaults(): array {
		return array(
			'default_conflict'       => Conflict_Resolver::SKIP,
			'match_by'               => 'slug',
			'restore_retention_days' => 30,
			'full_site_packages'     => 3,
			'capability'             => 'manage_options',
			'delete_on_uninstall'    => false,
		);
	}

	/**
	 * Every setting, defaults filled in.
	 *
	 * @return array<string,mixed>
	 */
	public static function all(): array {
		$stored = get_option( self::OPTION );

		return array_merge( self::defaults(), is_array( $stored ) ? $stored : array() );
	}

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

		return array_key_exists( $key, $all ) ? $all[ $key ] : null;
	}

	/**
	 * Write settings, dropping anything not in the schema.
	 *
	 * @param array<string,mixed> $values Incoming values.
	 * @return array<string,mixed> The settings as stored.
	 */
	public static function update( array $values ): array {
		$current = self::all();

		foreach ( $values as $key => $value ) {
			if ( ! array_key_exists( $key, self::defaults() ) ) {
				continue;
			}

			$current[ $key ] = self::sanitize( (string) $key, $value );
		}

		update_option( self::OPTION, $current );

		return $current;
	}

	/**
	 * The capability a request must hold, never weaker than the floor.
	 *
	 * @return string
	 */
	public static function capability(): string {
		$capability = (string) self::get( 'capability' );

		return in_array( $capability, self::CAPABILITIES, true ) ? $capability : 'manage_options';
	}

	/**
	 * Coerce one value into its allowed shape.
	 *
	 * @param string $key   Setting name.
	 * @param mixed  $value Incoming value.
	 * @return mixed
	 */
	private static function sanitize( string $key, $value ) {
		switch ( $key ) {
			case 'default_conflict':
				$value = sanitize_key( (string) $value );
				return in_array( $value, Conflict_Resolver::strategies(), true ) ? $value : Conflict_Resolver::SKIP;

			case 'match_by':
				return 'slug';

			case 'restore_retention_days':
				return max( 1, min( 365, (int) $value ) );

			case 'full_site_packages':
				return max( 1, min( Job_Store::LIMIT, (int) $value ) );

			case 'capability':
				$value = sanitize_key( (string) $value );
				return in_array( $value, self::CAPABILITIES, true ) ? $value : 'manage_options';

			case 'delete_on_uninstall':
				return (bool) $value;

			default:
				return $value;
		}
	}
}