<?php

namespace App\Events;

use App\Libraries\MY_Migration;
use App\Models\Appconfig;
use CodeIgniter\Session\Handlers\DatabaseHandler;
use CodeIgniter\Session\Handlers\FileHandler;
use CodeIgniter\Session\Session;
use Config\OSPOS;
use Config\Services;

/**
 * @property my_migration migration;
 * @property session session;
 * @property appconfig appconfig;
 * @property mixed $migration_config
 * @property mixed $config
 */
class Load_config
{
    public Session $session;

    /**
     * Loads configuration from database into App CI config and then applies those settings
     */
    public function load_config(): void
    {
        // Migrations
        $migration_config = config('Migrations');
        $migration = new MY_Migration($migration_config);

        // Use file-based session until database is migrated
        $this->session = $this->createSession($migration->is_latest());

        // Database Configuration
        $config = config(OSPOS::class);

        if (!$migration->is_latest()) {
            $this->session->destroy();
        }

        // Language
        $language_exists = file_exists('../app/Language/' . current_language_code());

        if (current_language_code() == null || current_language() == null || !$language_exists) {    // TODO: current_language() is undefined
            $config->settings['language'] = 'english';
            $config->settings['language_code'] = 'en';
        }

        $language = Services::language();
        $language->setLocale($config->settings['language_code']);

        // Time Zone
        date_default_timezone_set($config->settings['timezone'] ?? ini_get('date.timezone'));

        bcscale(max(2, totals_decimals() + tax_decimals()));
    }

    /**
     * Creates session with appropriate handler.
     * Uses file-based session until database is migrated, then switches to database session.
     * 
     * This prevents a circular dependency where login requires session, but the sessions
     * database table doesn't exist yet because migrations run after login.
     */
    private function createSession(bool $isDbMigrated): Session
    {
        $sessionConfig = config('Session');
        
        // If database is not migrated and we're configured to use database sessions,
        // temporarily fall back to file-based sessions to allow migrations to complete.
        // Once migrations run, the user must re-authenticate (session is destroyed in
        // load_config() when migrations are pending).
        if (!$isDbMigrated && $sessionConfig->driver === DatabaseHandler::class) {
            $sessionConfig = clone $sessionConfig;
            $sessionConfig->driver = FileHandler::class;
            $sessionConfig->savePath = WRITEPATH . 'session';
        }
        
        return Services::session($sessionConfig);
    }
}