<?php
function checkAuth(PDO $pdo): ?array {
    if (!isset($_SESSION['user_id'])) return null;
    $stmt = $pdo->prepare("SELECT * FROM users WHERE id = ?");
    $stmt->execute([$_SESSION['user_id']]);
    $user = $stmt->fetch();
    return $user ?: null;
}

function redirect(string $url): void {
    header("Location: $url");
    exit;
}

function getUserForms(PDO $pdo, int $userId): array {
    $stmt = $pdo->prepare("SELECT * FROM forms WHERE user_id = ? ORDER BY created_at DESC");
    $stmt->execute([$userId]);
    return $stmt->fetchAll();
}

function createLocalForm(PDO $pdo, ?int $userId, string $type, array $data, string $status = 'pending', ?string $priority = null, ?int $locationId = null): int {
    $jsonData = json_encode($data, JSON_UNESCAPED_UNICODE);
    $stmt = $pdo->prepare("INSERT INTO forms (user_id, type, data, status, priority, location_id) VALUES (?, ?, ?, ?, ?, ?)");
    $stmt->execute([$userId, $type, $jsonData, $status, $priority, $locationId]);
    return (int)$pdo->lastInsertId();
}

function uploadFile(array $file): string|false {
    if ($file['error'] !== UPLOAD_ERR_OK) return false;
    if ($file['size'] > MAX_FILE_SIZE) return false;
    $allowedTypes = ['image/jpeg', 'image/png', 'image/gif', 'application/pdf'];
    if (!in_array($file['type'], $allowedTypes)) return false;
    
    $ext = pathinfo($file['name'], PATHINFO_EXTENSION);
    $basename = bin2hex(random_bytes(16)) . '.' . $ext;
    $destination = UPLOAD_DIR . $basename;
    
    if (move_uploaded_file($file['tmp_name'], $destination)) {
        return 'uploads/' . $basename;
    }
    return false;
}

function syncFormWithGlpi(PDO $pdo, array &$form, GlpiApi $glpi): bool {
    $data = json_decode($form['data'], true);
    $glpiId = $data['glpi_ticket_id'] ?? null;
    if (!$glpiId) return true;

    $ticket = $glpi->getTicket($glpiId);
    if (!$ticket) {
        $stmt = $pdo->prepare("DELETE FROM forms WHERE id = ?");
        $stmt->execute([$form['id']]);
        return false;
    }

    $data['glpi_status'] = $ticket['status'] ?? null;
    $data['glpi_priority'] = $ticket['priority'] ?? null;
    $data['glpi_name'] = $ticket['name'] ?? '';
    $newData = json_encode($data, JSON_UNESCAPED_UNICODE);

    // ----- МАППИНГ СТАТУСОВ GLPI В ДОПУСТИМЫЕ ЗНАЧЕНИЯ -----
    $statusGlpi = strtolower($ticket['status_name'] ?? $ticket['status'] ?? 'unknown');
    
    $statusMap = [
        'new'        => 'pending',
        'incoming'   => 'pending',
        'waiting'    => 'pending',
        'processing' => 'processing',
        'assigned'   => 'processing',
        'solved'     => 'completed',
        'closed'     => 'completed',
        'rejected'   => 'rejected',
        'pending'    => 'pending'
    ];
    
    $newStatus = $statusMap[$statusGlpi] ?? 'pending';
    // Дополнительная проверка на допустимость
    $allowedStatuses = ['pending', 'processing', 'completed', 'rejected'];
    if (!in_array($newStatus, $allowedStatuses)) {
        $newStatus = 'pending';
    }
    
    // ----- МАППИНГ ПРИОРИТЕТОВ (ЧИСЛО -> 'low','medium','high') -----
    $priorityGlpi = $ticket['priority'] ?? 3; // число 1..5
    $priorityMap = [
        1 => 'low',
        2 => 'low',
        3 => 'medium',
        4 => 'high',
        5 => 'high'
    ];
    $newPriority = $priorityMap[$priorityGlpi] ?? 'medium';

    // Обновляем запись в БД
    $stmt = $pdo->prepare("UPDATE forms SET data = ?, status = ?, priority = ? WHERE id = ?");
    $stmt->execute([$newData, $newStatus, $newPriority, $form['id']]);

    $form['data'] = $newData;
    $form['status'] = $newStatus;
    $form['priority'] = $newPriority;
    return true;
}

/* ========== БАЗА ЗНАНИЙ (исправленная) ========== */

// Получение всех статей
function getAllLocalKnowledgeArticles(PDO $pdo): array {
    return $pdo->query("SELECT * FROM knowledge_base ORDER BY updated_at DESC")->fetchAll();
}

// Поиск с FULLTEXT или LIKE
function searchLocalKnowledgeFulltext(PDO $pdo, string $query, int $limit = 30): array {
    if (strlen($query) < 3) {
        $stmt = $pdo->prepare("SELECT id, title, SUBSTRING(content, 1, 200) AS preview, updated_at FROM knowledge_base WHERE title LIKE :q1 OR content LIKE :q2 ORDER BY updated_at DESC LIMIT $limit");
        $like = '%' . $query . '%';
        $stmt->execute(['q1' => $like, 'q2' => $like]);
        return $stmt->fetchAll();
    }
    $stmt = $pdo->prepare("SELECT id, title, SUBSTRING(content, 1, 200) AS preview, updated_at, MATCH(title, content) AGAINST(:query IN NATURAL LANGUAGE MODE) AS relevance FROM knowledge_base WHERE MATCH(title, content) AGAINST(:query IN NATURAL LANGUAGE MODE) ORDER BY relevance DESC LIMIT $limit");
    $stmt->execute(['query' => $query]);
    return $stmt->fetchAll();
}

// Инкрементальная синхронизация (с проверкой существования колонки)
function syncKnowledgeBaseIncremental(PDO $pdo, GlpiApi $glpi, array &$log = []): void {
    $log[] = "=== Инкрементальная синхронизация ===";
    
    // Проверяем наличие колонки glpi_updated_at
    try {
        $pdo->query("SELECT glpi_updated_at FROM knowledge_base LIMIT 1");
    } catch (PDOException $e) {
        $log[] = "Ошибка: колонка glpi_updated_at отсутствует. Выполните ALTER TABLE knowledge_base ADD COLUMN glpi_updated_at DATETIME DEFAULT NULL;";
        return;
    }
    
    $stmt = $pdo->query("SELECT MAX(glpi_updated_at) as last FROM knowledge_base");
    $lastSync = $stmt->fetch()['last'];
    $since = $lastSync ? $lastSync : '1970-01-01 00:00:00';
    
    $glpiItems = $glpi->searchKnowbaseItemsSince($since);
    $log[] = "Найдено изменённых статей в GLPI: " . count($glpiItems);
    
    foreach ($glpiItems as $glpiArticle) {
        $glpiId = (int)$glpiArticle['id'];
        $fullArticle = $glpi->getKnowbaseItem($glpiId);
        if (!$fullArticle) continue;
        
        $title = $fullArticle['name'];
        $content = $fullArticle['answer'] ?? '';
        $content = html_entity_decode($content, ENT_QUOTES | ENT_HTML5, 'UTF-8');
        $content = strip_tags($content, '<p><a><img><ul><li><ol><h1><h2><h3><h4><strong><em><span><div><br>');
        $glpiUpdatedAt = $fullArticle['date_mod'] ?? date('Y-m-d H:i:s');
        
        // Получаем документы (улучшенным методом)
        $docs = $glpi->getKnowbaseItemDocuments($glpiId);
        $log[] = "Статья GLPI #$glpiId: найдено документов: " . count($docs);
        $documentsMeta = [];
        foreach ($docs as $doc) {
            $documentsMeta[] = [
                'id' => $doc['id'],
                'name' => $doc['name'] ?? $doc['filename'] ?? "document_{$doc['id']}",
                'mime' => $doc['mime'] ?? '',
                'path' => null // путь будет установлен при первом скачивании
            ];
        }
        
        $existing = findLocalKnowledgeByGlpiId($pdo, $glpiId);
        if ($existing) {
            updateLocalKnowledgeArticleMeta($pdo, $existing['id'], $title, $content, $documentsMeta, $glpiUpdatedAt);
            $log[] = "Обновлена статья GLPI #$glpiId";
        } else {
            insertLocalKnowledgeArticle($pdo, $glpiId, $title, $content, $documentsMeta, $glpiUpdatedAt);
            $log[] = "Добавлена новая статья GLPI #$glpiId";
        }
    }
    $log[] = "=== Синхронизация завершена ===";
}

function findLocalKnowledgeByGlpiId(PDO $pdo, int $glpiId): ?array {
    $stmt = $pdo->prepare("SELECT * FROM knowledge_base WHERE glpi_id = ?");
    $stmt->execute([$glpiId]);
    return $stmt->fetch() ?: null;
}

function insertLocalKnowledgeArticle(PDO $pdo, int $glpiId, string $title, string $content, array $documents, string $glpiUpdatedAt): int {
    $stmt = $pdo->prepare("INSERT INTO knowledge_base (glpi_id, title, content, documents, glpi_updated_at) VALUES (?, ?, ?, ?, ?)");
    $stmt->execute([$glpiId, $title, $content, json_encode($documents, JSON_UNESCAPED_UNICODE), $glpiUpdatedAt]);
    return (int)$pdo->lastInsertId();
}

function updateLocalKnowledgeArticleMeta(PDO $pdo, int $localId, string $title, string $content, array $documents, string $glpiUpdatedAt): void {
    $stmt = $pdo->prepare("SELECT documents FROM knowledge_base WHERE id = ?");
    $stmt->execute([$localId]);
    $old = $stmt->fetch();
    $oldDocs = json_decode($old['documents'], true);
    // Сохраняем уже скачанные пути
    foreach ($documents as &$newDoc) {
        foreach ($oldDocs as $oldDoc) {
            if ($oldDoc['id'] == $newDoc['id'] && isset($oldDoc['path'])) {
                $newDoc['path'] = $oldDoc['path'];
                break;
            }
        }
    }
    $update = $pdo->prepare("UPDATE knowledge_base SET title = ?, content = ?, documents = ?, glpi_updated_at = ?, updated_at = NOW() WHERE id = ?");
    $update->execute([$title, $content, json_encode($documents, JSON_UNESCAPED_UNICODE), $glpiUpdatedAt, $localId]);
}

function getLocalKnowledgeArticle(PDO $pdo, int $id): ?array {
    $stmt = $pdo->prepare("SELECT * FROM knowledge_base WHERE id = ?");
    $stmt->execute([$id]);
    return $stmt->fetch() ?: null;
}

function lazyLoadDocument(PDO $pdo, int $knowledgeId, int $docId, string $docName, string $docMime, GlpiApi $glpi): ?string {
    $safeName = $docId . '_' . sanitizeFileName($docName);
    $cachePath = KB_CACHE_DIR . $safeName;
    if (file_exists($cachePath)) {
        return $cachePath;
    }
    $content = $glpi->getDocumentContent($docId);
    if ($content === null) return null;
    if (file_put_contents($cachePath, $content)) {
        // Обновляем путь в БД
        $stmt = $pdo->prepare("SELECT documents FROM knowledge_base WHERE id = ?");
        $stmt->execute([$knowledgeId]);
        $row = $stmt->fetch();
        $docs = json_decode($row['documents'], true);
        foreach ($docs as &$d) {
            if ($d['id'] == $docId) {
                $d['path'] = $safeName;
                break;
            }
        }
        $update = $pdo->prepare("UPDATE knowledge_base SET documents = ? WHERE id = ?");
        $update->execute([json_encode($docs), $knowledgeId]);
        return $cachePath;
    }
    return null;
}

function sanitizeFileName(string $name): string {
    $name = basename($name);
    return preg_replace('/[^a-zA-Z0-9_\-\.]/u', '_', $name);
}

function getDocumentUrl(PDO $pdo, int $knowledgeId, int $docId): ?string {
    $stmt = $pdo->prepare("SELECT documents FROM knowledge_base WHERE id = ?");
    $stmt->execute([$knowledgeId]);
    $row = $stmt->fetch();
    if (!$row) return null;
    $docs = json_decode($row['documents'], true);
    foreach ($docs as $doc) {
        if ($doc['id'] == $docId) {
            if (!empty($doc['path']) && file_exists(KB_CACHE_DIR . $doc['path'])) {
                return 'get_document.php?kid=' . $knowledgeId . '&doc=' . $docId;
            } else {
                // Файл ещё не скачан, но ссылка та же - будет скачан при запросе
                return 'get_document.php?kid=' . $knowledgeId . '&doc=' . $docId;
            }
        }
    }
    return null;
}