<?php
/**
 * Creates and upgrades the plugin's database table.
 *
 * @package Fitzaro
 */

namespace Fitzaro\Database;

defined( 'ABSPATH' ) || exit;

/**
 * Runs dbDelta only when the stored schema version differs from Schema::VERSION,
 * so normal page loads cost one autoloaded option read.
 */
final class Installer {

	public const VERSION_OPTION = 'fitzaro_db_version';

	/**
	 * Activation hook: always make sure the table exists.
	 */
	public static function activate(): void {
		self::install();
	}

	/**
	 * Upgrades the table after a plugin update. Called on every request, cheap when up to date.
	 */
	public static function maybe_upgrade(): void {
		if ( ! self::needs_upgrade( get_option( self::VERSION_OPTION, '' ) ) ) {
			return;
		}

		self::install();
	}

	/**
	 * Whether the stored version differs from the code's schema version.
	 *
	 * @param mixed $stored_version Value of the version option.
	 */
	public static function needs_upgrade( $stored_version ): bool {
		return Schema::VERSION !== (string) $stored_version;
	}

	/**
	 * Creates or alters the table, then records the version.
	 */
	private static function install(): void {
		global $wpdb;

		require_once ABSPATH . 'wp-admin/includes/upgrade.php';

		dbDelta( Schema::create_table_sql( Schema::table_name( $wpdb->prefix ), $wpdb->get_charset_collate() ) );

		update_option( self::VERSION_OPTION, Schema::VERSION, true );
	}
}