<?php
declare(strict_types=1);

/**
 * Thought Gallery events chat — loads credentials from /home/home2/cgny/.env
 */
final class EventsChatConfig
{
    private static ?array $cfg = null;

    public static function get(): array
    {
        if (self::$cfg !== null) {
            return self::$cfg;
        }

        $envPath = '/home/home2/cgny/.env';
        if (!is_readable($envPath)) {
            throw new RuntimeException('Config file not readable.');
        }

        $raw = file_get_contents($envPath);
        if ($raw === false) {
            throw new RuntimeException('Unable to read config file.');
        }

        if (!preg_match('/db\s*=\s*(\S+)\s*\/\s*(\S+)/i', $raw, $dbMatch)) {
            throw new RuntimeException('DB credentials missing from config.');
        }
        if (!preg_match('/([a-z0-9.-]+\.rds\.amazonaws\.com)/i', $raw, $hostMatch)) {
            throw new RuntimeException('DB host missing from config.');
        }
        if (!preg_match('/(?:openapi|openai)\s*key\s*=\s*(sk-[A-Za-z0-9_\-]+)/i', $raw, $keyMatch)) {
            throw new RuntimeException('OpenAI API key missing from config.');
        }

        self::$cfg = [
            'db_host' => $hostMatch[1],
            'db_user' => $dbMatch[1],
            'db_pass' => $dbMatch[2],
            'db_name' => 'tgnew_prod',
            'openai_api_key' => $keyMatch[1],
            'openai_model' => 'gpt-4o-mini',
            'admin_password' => $dbMatch[2],
            'event_base_url' => 'https://thoughtgallery.org/events/',
            'cache_path' => __DIR__ . '/cache/events.json',
            'cache_max_age_seconds' => 90 * 60,
            'history_limit' => 12,
            'rate_input' => 0.15,
            'rate_cached_input' => 0.075,
            'rate_output' => 0.60,
        ];

        return self::$cfg;
    }
}