<?php
/**
 * Moving over from the plugin "Classic Editor".
 *
 * Site settings are copied once on activation. The per-user and per-post choices it stored are
 * read as a fallback, so nothing has to be rewritten in the database.
 *
 * @package ThreeCE
 */

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

/**
 * Migration from Classic Editor.
 */
class ThreeCE_Migrate {

	/**
	 * Activation: copies the Classic Editor site settings unless we already have our own. Activated for a whole
	 * network, every site takes over its own values.
	 *
	 * @param mixed $network_wide True when activated network-wide (from register_activation_hook).
	 */
	public static function activate( $network_wide = false ): void {
		self::each_site( $network_wide, array( __CLASS__, 'activate_site' ) );
	}

	/**
	 * Runs a callback on every site of the network for a network-wide activation, otherwise on the current site.
	 *
	 * @param mixed    $network_wide True for the whole network.
	 * @param callable $callback     Called once per site.
	 */
	public static function each_site( $network_wide, $callback ): void {
		if ( ! $network_wide || ! is_multisite() ) {
			call_user_func( $callback );
			return;
		}
		foreach ( get_sites(
			array(
				'fields' => 'ids',
				'number' => 0,
			)
		) as $site_id ) {
			switch_to_blog( (int) $site_id );
			call_user_func( $callback );
			restore_current_blog();
		}
	}

	/**
	 * Takes over the Classic Editor values of the current site, once.
	 */
	public static function activate_site(): void {
		if ( false !== get_option( ThreeCE_Editor_Switch::OPTION ) ) {
			return;
		}
		$replace = get_option( 'classic-editor-replace' );
		$allow   = get_option( 'classic-editor-allow-users' );
		if ( false === $replace && false === $allow ) {
			return;
		}
		update_option(
			ThreeCE_Editor_Switch::OPTION,
			array(
				// Classic Editor still accepts its old values "replace" and "no-replace".
				'editor'      => ( 'block' === $replace || 'no-replace' === $replace ) ? 'block' : 'classic',
				'allow_users' => ( 'allow' === $allow ),
			)
		);
	}

	/**
	 * Editor Classic Editor remembered for a post, or ''.
	 *
	 * @param int $post_id Post ID.
	 * @return string
	 */
	public static function post_editor( $post_id ) {
		$which = get_post_meta( $post_id, 'classic-editor-remember', true );
		if ( 'block-editor' === $which ) {
			return 'block';
		}
		return ( 'classic-editor' === $which ) ? 'classic' : '';
	}

	/**
	 * Default editor a user chose in Classic Editor, or ''.
	 *
	 * @param int $user_id User ID.
	 * @return string
	 */
	public static function user_editor( $user_id ) {
		$which = get_user_option( 'classic-editor-settings', $user_id );
		return ( 'block' === $which || 'classic' === $which ) ? $which : '';
	}
}