<?php
require_once dirname(__DIR__, 2) . '/vendor/autoload.php';
require_once __DIR__ . '/class/db-functions.php';
include dirname(__DIR__) . '/../extra/auth.php';
if (!Auth::check()) {
    http_response_code(401);
    echo json_encode(['error' => 'Unauthorized']);
    exit;
}

require_once __DIR__ . '/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;
$rawLimit = intval($_GET['limit'] ?? 20);
$limit = $rawLimit <= 0 ? 0 : max(1, min(500, $rawLimit));

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 — multi-term AND, position-independent, ranked
    $terms = array_values(array_filter(
        preg_split('/\s+/u', $q, -1, PREG_SPLIT_NO_EMPTY)
    ));

    // Nessun termine digitato: alfabetico, taglio al limite
    if (empty($terms)) {
        $all = [];
        foreach ($values as $v) {
            $all[] = ['id' => $v['IdCustomFieldsValue'], 'text' => $v['Valore'] ?? ''];
        }
        usort($all, fn($a, $b) => strcasecmp($a['text'], $b['text']));
        if ($limit > 0) $all = array_slice($all, 0, $limit);
        echo json_encode(['results' => $all]);
        exit;
    }

    $firstTerm = $terms[0];
    $scored = [];

    foreach ($values as $v) {
        $text = $v['Valore'] ?? '';
        $textLower = mb_strtolower($text);

        // AND: tutti i termini devono essere presenti, in qualsiasi posizione
        $matchAll = true;
        foreach ($terms as $t) {
            if (mb_strpos($textLower, $t) === false) {
                $matchAll = false;
                break;
            }
        }
        if (!$matchAll) continue;

        // Punteggio di pertinenza (più basso = più rilevante)
        if ($textLower === $q) {
            $score = 0;                                   // match esatto
        } elseif (mb_strpos($textLower, $firstTerm) === 0) {
            $score = 1;                                   // inizia col primo termine
        } elseif (preg_match('/(^|\s)' . preg_quote($firstTerm, '/') . '/u', $textLower)) {
            $score = 2;                                   // primo termine a inizio di una parola
        } else {
            $score = 3;                                   // presente ma non a inizio parola
        }

        $scored[] = [
            'id'   => $v['IdCustomFieldsValue'],
            'text' => $text,
            '_s'   => $score,
            '_n'   => $textLower
        ];
    }

    // Ordina per punteggio, poi alfabetico
    usort($scored, function ($a, $b) {
        if ($a['_s'] !== $b['_s']) return $a['_s'] - $b['_s'];
        return strcmp($a['_n'], $b['_n']);
    });

    // Taglia DOPO l'ordinamento e rimuovi i campi interni
    if ($limit > 0) {
        $scored = array_slice($scored, 0, $limit);
    }

    $results = array_map(
        fn($r) => ['id' => $r['id'], 'text' => $r['text']],
        $scored
    );

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