<?php
class SmsService {
    public static function sendSms($to, $message) {
        $sms_config = require __DIR__ . '/../config/sms.php';
        $api_key = $sms_config['smslink']['api_key'];
        $sender = $sms_config['smslink']['sender'];

        if ($api_key === 'YOUR_SMSLINK_API_KEY') {
            // Don't send SMS if the API key is not set
            error_log('SMS not sent: SMSLink API key is not set.');
            return ['success' => false, 'error' => 'SMSLink API key is not set.'];
        }

        $url = 'https://secure.smslink.ro/sms/gateway/communicate/index.php';
        $post_fields = [
            'connection_id' => $api_key,
            'to' => $to,
            'message' => $message,
            'sender' => $sender,
        ];

        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_POST, true);
        curl_setopt($ch, CURLOPT_POSTFIELDS, http_build_query($post_fields));
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

        $response = curl_exec($ch);
        $err = curl_error($ch);

        curl_close($ch);

        if ($err) {
            return ['success' => false, 'error' => $err];
        } else {
            // Basic check for success response from SMSLink
            if (strpos($response, 'RESPONSE_CODE: 0') !== false) {
                return ['success' => true];
            } else {
                return ['success' => false, 'error' => $response];
            }
        }
    }
}