<?php
if ( ! defined( 'ABSPATH' ) ) {
    exit;
}

class WPVFB_DB {
    const DB_VERSION = '2';

    public static function activate() {
        global $wpdb;
        $charset_collate = $wpdb->get_charset_collate();

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

        $table_forms = $wpdb->prefix . 'wpvfb_forms';
        $sql_forms = "CREATE TABLE $table_forms (
            id varchar(36) NOT NULL,
            name varchar(255) NOT NULL,
            fields longtext NULL,
            settings longtext NULL,
            confirmations longtext NULL,
            notifications longtext NULL,
            is_active tinyint(1) DEFAULT 1 NOT NULL,
            created_at datetime DEFAULT CURRENT_TIMESTAMP NOT NULL,
            updated_at datetime DEFAULT CURRENT_TIMESTAMP ON UPDATE CURRENT_TIMESTAMP NOT NULL,
            PRIMARY KEY  (id)
        ) $charset_collate;";

        dbDelta( $sql_forms );

        $table_entries = $wpdb->prefix . 'wpvfb_entries';
        $sql_entries = "CREATE TABLE $table_entries (
            id varchar(36) NOT NULL,
            form_id varchar(36) NOT NULL,
            data longtext NOT NULL,
            user_ip varchar(45) NULL,
            user_agent text NULL,
            created_at datetime DEFAULT CURRENT_TIMESTAMP NOT NULL,
            PRIMARY KEY  (id),
            KEY form_id (form_id)
        ) $charset_collate;";

        dbDelta( $sql_entries );

        update_option( 'wpvfb_db_version', self::DB_VERSION );
    }

    /**
     * Activation hooks do not run on plugin updates, so new columns are added here.
     * dbDelta only adds missing columns; existing data is never dropped.
     */
    public static function maybe_upgrade() {
        if ( get_option( 'wpvfb_db_version' ) !== self::DB_VERSION ) {
            self::activate();
        }
    }
}