<?php
defined($security_key) or exit;

//------------------------------------------
// VAT Number Validation (VIES Proxy)
//------------------------------------------

// CONTENT FROM API (POST)
$post_content = json_decode($input, true);

// Validate input
if (empty($post_content['countryCode']) || empty($post_content['vatNumber'])) {
    http_response_code(400);
    echo json_encode([
        'error' => 'Missing required parameters: countryCode and vatNumber'
    ]);
    exit;
}

$countryCode = strtoupper(trim($post_content['countryCode']));
$vatNumber = $post_content['vatNumber'];

// Remove all whitespace from VAT number
$vatNumber = preg_replace('/\s+/', '', $vatNumber);

// Remove country code prefix if included in VAT number
if (strpos($vatNumber, $countryCode) === 0) {
    $vatNumber = substr($vatNumber, strlen($countryCode));
}

// VIES API endpoint
$viesUrl = 'https://ec.europa.eu/taxation_customs/vies/rest-api/check-vat-number';

// Prepare request data
$requestData = json_encode([
    'countryCode' => $countryCode,
    'vatNumber' => $vatNumber
]);

// Initialize cURL
$ch = curl_init($viesUrl);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
curl_setopt($ch, CURLOPT_POST, true);
curl_setopt($ch, CURLOPT_POSTFIELDS, $requestData);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    'Content-Type: application/json',
    'Accept: application/json'
]);
curl_setopt($ch, CURLOPT_TIMEOUT, 10); // 10 second timeout

// Execute request
$response = curl_exec($ch);
$httpCode = curl_getinfo($ch, CURLINFO_HTTP_CODE);
$curlError = curl_error($ch);
curl_close($ch);

// Check for cURL errors
if ($curlError) {
    http_response_code(500);
    echo json_encode([
        'error' => 'Failed to connect to VIES service',
        'details' => $curlError
    ]);
    exit;
}

// Parse VIES response regardless of HTTP code
$viesData = json_decode($response, true);

// If we can't parse JSON, return an error
if (json_last_error() !== JSON_ERROR_NONE) {
    http_response_code(500);
    echo json_encode([
        'error' => 'Invalid response from VIES service',
        'httpCode' => $httpCode,
        'response' => $response
    ]);
    exit;
}

// Always return 200 OK to the client with the VIES data
// The client will check the 'valid' field in the response
http_response_code(200);
echo json_encode($viesData);

?>