<?php
require_once dirname(__DIR__, 2) . '/vendor/autoload.php';
require_once dirname(__FILE__) . '/class/VisualLimsApiClient.class.php';

header('Content-Type: application/json');
ini_set('display_errors', '0');
error_reporting(E_ALL);

$fieldId = intval($_GET['field_id'] ?? 0);
$q = mb_strtolower(trim($_GET['q'] ?? ''));
$id = isset($_GET['id']) ? intval($_GET['id']) : null;
$limit = max(1, min(50, intval($_GET['limit'] ?? 20)));

if (!$fieldId) {
    echo json_encode(['results' => []]);
    exit;
}

try {
    $cacheDir = __DIR__ . '/cache';
    $cacheFile = $cacheDir . '/customfield_' . $fieldId . '.json';

    if (file_exists($cacheFile) && (time() - filemtime($cacheFile) < 3600)) {
        $values = json_decode(file_get_contents($cacheFile), true);
    } else {
        $api = VisualLimsApiClient::getInstance();
        $data = $api->get("CustomField($fieldId)?\$expand=CustomFieldsValues");
        $values = $data['CustomFieldsValues'] ?? [];
        if (!is_dir($cacheDir)) mkdir($cacheDir, 0777, true);
        file_put_contents($cacheFile, json_encode($values));
    }

    // Lookup by ID
    if ($id !== null) {
        foreach ($values as $v) {
            if ((int)($v['IdCustomFieldsValue'] ?? 0) === $id) {
                echo json_encode(['results' => [['id' => $v['IdCustomFieldsValue'], 'text' => $v['Valore'] ?? '']]]);
                exit;
            }
        }
        echo json_encode(['results' => []]);
        exit;
    }

    // Search by query
    $results = [];
    foreach ($values as $v) {
        $text = $v['Valore'] ?? '';
        if ($q === '' || mb_strpos(mb_strtolower($text), $q) !== false) {
            $results[] = ['id' => $v['IdCustomFieldsValue'], 'text' => $text];
            if (count($results) >= $limit) break;
        }
    }

    // Sort alphabetically
    usort($results, fn($a, $b) => strcasecmp($a['text'], $b['text']));

    echo json_encode(['results' => $results]);
} catch (Exception $e) {
    http_response_code(500);
    echo json_encode(['error' => $e->getMessage()]);
}