<?php

/**
 * Creating a ticket as a user: required-field and required-custom-field
 * validation, TicketModel::createTicket (which enforces visibility rules),
 * audit log, stats-cache invalidation, custom field values, optional
 * "duplicates" link, and the new-ticket Matrix notification.
 *
 * Shared by the web UI (TicketController::create) and the MCP create_ticket
 * tool so both run one code path (tinker_tickets#111). Extracted from
 * TicketController::create with the same checks, order and error messages.
 * Callers own request parsing, CSRF, and rendering.
 */

require_once dirname(__DIR__) . '/models/TicketModel.php';
require_once dirname(__DIR__) . '/models/AuditLogModel.php';
require_once dirname(__DIR__) . '/models/CustomFieldModel.php';
require_once dirname(__DIR__) . '/models/StatsModel.php';
require_once dirname(__DIR__) . '/helpers/NotificationHelper.php';

class TicketCreationService
{
    /**
     * @param array $currentUser Authenticated user row
     * @param array $input       title, description, priority, category, type, status,
     *                           visibility, visibility_groups (string or list), assigned_to,
     *                           custom_fields (field_id => value), link_duplicate_of
     *
     * @return array ['success' => true, 'ticket_id' => ...] or ['success' => false, 'error' => ...]
     */
    public static function create(mysqli $conn, array $currentUser, array $input): array
    {
        $userId = $currentUser['user_id'] ?? null;

        // Handle visibility groups (a list from the web form's checkboxes, or a string)
        $visibilityGroups = null;
        if (isset($input['visibility_groups']) && is_array($input['visibility_groups'])) {
            $visibilityGroups = implode(',', array_map('trim', $input['visibility_groups']));
        } elseif (isset($input['visibility_groups']) && is_string($input['visibility_groups']) && trim($input['visibility_groups']) !== '') {
            $visibilityGroups = trim($input['visibility_groups']);
        }

        // Honor the posted status, validated against the app's canonical list
        $validStatuses = $GLOBALS['config']['TICKET_STATUSES'] ?? ['Open', 'Pending', 'In Progress', 'Closed'];
        $status = $input['status'] ?? 'Open';
        if (!in_array($status, $validStatuses, true)) {
            $status = 'Open';
        }

        $ticketData = [
            'title' => trim($input['title'] ?? ''),
            'description' => $input['description'] ?? '',
            'priority' => $input['priority'] ?? '4',
            'category' => $input['category'] ?? 'General',
            'type' => $input['type'] ?? 'Issue',
            'status' => $status,
            'visibility' => $input['visibility'] ?? 'public',
            'visibility_groups' => $visibilityGroups,
            'assigned_to' => !empty($input['assigned_to']) ? $input['assigned_to'] : null
        ];

        if ($ticketData['title'] === '') {
            return ['success' => false, 'error' => 'Title is required'];
        }

        if (trim($ticketData['description']) === '') {
            return ['success' => false, 'error' => 'Description is required'];
        }

        // Custom fields applicable to the submitted category — validate
        // is_required server-side (the form is novalidate, and a field
        // hidden by the client-side category toggle must not silently
        // bypass a requirement that applies to the category actually
        // submitted).
        $customFieldModel = new CustomFieldModel($conn);
        $allCustomFieldDefs = $customFieldModel->getAllDefinitions(null, true);
        $submittedCustomFields = is_array($input['custom_fields'] ?? null) ? $input['custom_fields'] : [];
        $applicableFieldDefs = array_filter(
            $allCustomFieldDefs,
            fn($def) => $def['category'] === null || $def['category'] === $ticketData['category']
        );
        $customFieldsToSave = [];
        foreach ($applicableFieldDefs as $def) {
            $fieldId = (int)$def['field_id'];
            $raw = $submittedCustomFields[$fieldId] ?? null;
            $normalized = $def['field_type'] === 'checkbox'
                ? (!empty($raw) ? '1' : '0')
                : (is_scalar($raw) ? trim((string)$raw) : '');

            if (!empty($def['is_required']) && $def['field_type'] !== 'checkbox' && $normalized === '') {
                return ['success' => false, 'error' => $def['field_label'] . ' is required'];
            }

            if ($normalized !== '') {
                $customFieldsToSave[$fieldId] = $normalized;
            }
        }

        // Create ticket with user tracking
        $result = (new TicketModel($conn))->createTicket($ticketData, $userId);
        if (!$result['success']) {
            return ['success' => false, 'error' => $result['error']];
        }

        // Log ticket creation to audit log
        if ($userId) {
            (new AuditLogModel($conn))->logTicketCreate($userId, $result['ticket_id'], $ticketData);
        }

        // Ticket counts changed — invalidate the cached dashboard stats
        (new StatsModel($conn))->invalidateCache();

        // Persist custom field values for the fields applicable to this ticket's category
        if (!empty($customFieldsToSave)) {
            $customFieldModel->setValues($result['ticket_id'], $customFieldsToSave);
        }

        // Auto-link as duplicate if requested
        $linkDupOfRaw = trim((string)($input['link_duplicate_of'] ?? ''));
        if ($linkDupOfRaw !== '' && ctype_digit($linkDupOfRaw)) {
            $depSql = "INSERT IGNORE INTO ticket_dependencies (ticket_id, depends_on_id, dependency_type, created_by)
                       VALUES (?, ?, 'duplicates', ?)";
            $depStmt = $conn->prepare($depSql);
            $depStmt->bind_param("ssi", $result['ticket_id'], $linkDupOfRaw, $userId);
            $depStmt->execute();
            $depStmt->close();
        }

        // Send Matrix notification for new ticket
        NotificationHelper::sendTicketNotification($result['ticket_id'], $ticketData, 'manual');

        return ['success' => true, 'ticket_id' => $result['ticket_id']];
    }
}