<?php
/**
 * Settings management for the AI Translator plugin.
 *
 * @package ROBOTSTXT\AI_Translator
 * @since   1.0.0
 */

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

if ( ! class_exists( 'AI_Translator_Settings' ) ) {

	/**
	 * Handles reading and writing the plugin settings in single-site and Multisite contexts.
	 *
	 * In Multisite, the network admin chooses between two modes:
	 *  - "global"   : a single configuration shared by every subsite.
	 *  - "per-site" : each subsite stores its own configuration, with the network values
	 *                 acting as defaults when a subsite has not been configured yet.
	 *
	 * @since 1.0.0
	 */
	class AI_Translator_Settings {

		/**
		 * Option key for site-level settings (single-site or per-site Multisite mode).
		 *
		 * @since 1.0.0
		 * @var string
		 */
		const OPTION_SITE = 'ai_translator_settings';

		/**
		 * Sitemeta key for network-level settings (Multisite global mode and defaults).
		 *
		 * @since 1.0.0
		 * @var string
		 */
		const OPTION_NETWORK = 'ai_translator_settings';

		/**
		 * Sitemeta key for the configuration mode in Multisite.
		 *
		 * @since 1.0.0
		 * @var string
		 */
		const OPTION_MODE = 'ai_translator_network_mode';

		/**
		 * Default settings values.
		 *
		 * @since 1.0.0
		 * @var array<string,bool>
		 */
		const DEFAULTS = array(
			'translate_title'              => true,
			'translate_content'            => true,
			'translate_excerpt'            => true,
			'auto_translate_on_mlp_create' => false,
		);

		/**
		 * Returns the current configuration mode in Multisite.
		 *
		 * @since 1.0.0
		 *
		 * @return string Either 'global' or 'per-site'. Returns 'global' on single-site installs.
		 */
		public function get_network_mode() {
			if ( ! is_multisite() ) {
				return 'global';
			}

			$mode = get_site_option( self::OPTION_MODE, 'global' );

			return in_array( $mode, array( 'global', 'per-site' ), true ) ? $mode : 'global';
		}

		/**
		 * Updates the Multisite configuration mode.
		 *
		 * @since 1.0.0
		 *
		 * @param string $mode Either 'global' or 'per-site'.
		 *
		 * @return bool True on success.
		 */
		public function update_network_mode( $mode ) {
			if ( ! is_multisite() ) {
				return false;
			}

			$mode = in_array( $mode, array( 'global', 'per-site' ), true ) ? $mode : 'global';

			return (bool) update_site_option( self::OPTION_MODE, $mode );
		}

		/**
		 * Returns the effective settings for a given site, applying multisite mode rules.
		 *
		 * @since 1.0.0
		 *
		 * @param int|null $blog_id Optional blog ID. Defaults to the current site.
		 *
		 * @return array<string,bool> Settings array with boolean values.
		 */
		public function get_settings( $blog_id = null ) {
			if ( ! is_multisite() ) {
				return $this->normalize( (array) get_option( self::OPTION_SITE, array() ) );
			}

			$mode = $this->get_network_mode();

			if ( 'global' === $mode ) {
				return $this->normalize( (array) get_site_option( self::OPTION_NETWORK, array() ) );
			}

			$network_defaults = $this->normalize( (array) get_site_option( self::OPTION_NETWORK, array() ) );

			if ( null === $blog_id || get_current_blog_id() === (int) $blog_id ) {
				$site_settings = get_option( self::OPTION_SITE, null );
			} else {
				switch_to_blog( (int) $blog_id );
				$site_settings = get_option( self::OPTION_SITE, null );
				restore_current_blog();
			}

			if ( null === $site_settings ) {
				return $network_defaults;
			}

			return $this->normalize( array_merge( $network_defaults, (array) $site_settings ) );
		}

		/**
		 * Returns the raw network-level settings (used by the network admin form).
		 *
		 * @since 1.0.0
		 *
		 * @return array<string,bool>
		 */
		public function get_network_settings() {
			return $this->normalize( (array) get_site_option( self::OPTION_NETWORK, array() ) );
		}

		/**
		 * Returns the raw site-level settings (used by the site admin form).
		 *
		 * @since 1.0.0
		 *
		 * @return array<string,bool>
		 */
		public function get_site_settings() {
			return $this->normalize( (array) get_option( self::OPTION_SITE, array() ) );
		}

		/**
		 * Persists the network-level settings (Multisite only).
		 *
		 * @since 1.0.0
		 *
		 * @param array<string,bool> $settings Settings to store.
		 *
		 * @return bool True on success.
		 */
		public function update_network_settings( array $settings ) {
			if ( ! is_multisite() ) {
				return false;
			}

			return (bool) update_site_option( self::OPTION_NETWORK, $this->normalize( $settings ) );
		}

		/**
		 * Persists the site-level settings.
		 *
		 * @since 1.0.0
		 *
		 * @param array<string,bool> $settings Settings to store.
		 *
		 * @return bool True on success.
		 */
		public function update_site_settings( array $settings ) {
			return (bool) update_option( self::OPTION_SITE, $this->normalize( $settings ) );
		}

		/**
		 * Normalises raw settings into a strict array of booleans matching the schema.
		 *
		 * @since 1.0.0
		 *
		 * @param array<int|string,mixed> $settings Raw settings.
		 *
		 * @return array<string,bool>
		 */
		private function normalize( array $settings ) {
			$normalized = array();

			foreach ( self::DEFAULTS as $key => $default ) {
				if ( array_key_exists( $key, $settings ) ) {
					$normalized[ $key ] = (bool) $settings[ $key ];
				} else {
					$normalized[ $key ] = (bool) $default;
				}
			}

			return $normalized;
		}
	}
}