<?php
$apiKey = 'YOUR_API_KEY';
$baseUrl = 'https://wa.libertaspro.io/api';
$sessionId = 'your-session-id';

function sendMessage($to, $message) {
    global $apiKey, $baseUrl, $sessionId;

    $url = "$baseUrl/sessions/$sessionId/send";
    $data = json_encode(['to' => $to, 'message' => $message]);

    $ch = curl_init($url);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_POST, true);
    curl_setopt($ch, CURLOPT_POSTFIELDS, $data);
    curl_setopt($ch, CURLOPT_HTTPHEADER, [
        'Content-Type: application/json',
        "X-API-Key: $apiKey"
    ]);

    $response = curl_exec($ch);
    curl_close($ch);
    return json_decode($response, true);
}

$result = sendMessage('1234567890', 'Hello from PHP!');
print_r($result);
?>