<?php
/**
 * Upgrade/migration helpers.
 *
 * @package AgenizedChatWidget
 */

namespace AgenizedChatWidget;

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

final class Upgrade {
	private const MIGRATION_DONE_OPTION = 'agenized_chat_widget_migration_done_v1';

	public static function init(): void {
		add_action('plugins_loaded', [self::class, 'run_migrations'], 5);
	}

	public static function run_migrations(): void {
		if (self::option_exists(self::MIGRATION_DONE_OPTION)) {
			return;
		}

		self::migrate_legacy_option_keys();
		update_option(self::MIGRATION_DONE_OPTION, '1', false);
	}

	private static function migrate_legacy_option_keys(): void {
		$legacy_to_current = [
			'agenized_api_base_url' => Options::OPT_API_BASE_URL,
			'agenized_widget_api_base_url' => Options::OPT_WIDGET_API_BASE_URL,
			'agenized_portal_base_url' => Options::OPT_PORTAL_BASE_URL,
			'agenized_widget_script_url' => Options::OPT_WIDGET_SCRIPT_URL,
			'agenized_signup_url' => Options::OPT_SIGNUP_URL,
			'agenized_oauth_client_id' => Options::OPT_OAUTH_CLIENT_ID,
			'agenized_oauth_client_secret' => Options::OPT_OAUTH_CLIENT_SECRET,
			'agenized_oauth_scopes' => Options::OPT_OAUTH_SCOPES,
			'agenized_access_token' => Options::OPT_ACCESS_TOKEN,
			'agenized_refresh_token' => Options::OPT_REFRESH_TOKEN,
			'agenized_token_expires_at' => Options::OPT_TOKEN_EXPIRES_AT,
			'agenized_channel_id' => Options::OPT_CHANNEL_ID,
			'agenized_channel_public_key' => Options::OPT_CHANNEL_PUBLIC_KEY,
			'agenized_wc_action_connection_id' => Options::OPT_WC_ACTION_CONNECTION_ID,
			'agenized_wc_key_id' => Options::OPT_WC_KEY_ID,
			'agenized_orders_webhook_secret' => Options::OPT_ORDERS_WEBHOOK_SECRET,
			'agenized_enable_context_events' => Options::OPT_ENABLE_CONTEXT_EVENTS,
			'agenized_enable_order_webhooks' => Options::OPT_ENABLE_ORDER_WEBHOOKS,
		];

		foreach ($legacy_to_current as $legacy_key => $current_key) {
			$current_value = get_option($current_key, null);
			if (self::has_meaningful_value($current_value)) {
				continue;
			}

			if (!self::option_exists($legacy_key)) {
				continue;
			}

			$legacy_value = get_option($legacy_key, null);
			if ($legacy_value === null) {
				continue;
			}

			update_option($current_key, $legacy_value, false);
		}
	}

	private static function option_exists(string $key): bool {
		$sentinel = '__agenized_missing__';
		$value = get_option($key, $sentinel);
		return $value !== $sentinel;
	}

	/**
	 * Treat empty strings/null as not set; booleans/integers are meaningful.
	 *
	 * @param mixed $value Option value.
	 */
	private static function has_meaningful_value($value): bool {
		if ($value === null) {
			return false;
		}
		if (is_string($value)) {
			return trim($value) !== '';
		}
		return true;
	}
}