<?php

/**
 * ticket_status_api.php — Bearer-key endpoint to change a ticket's status.
 *
 * POST only. Requires 'read_write' scope.
 *
 * Body (JSON): {
 *   "ticket_id":        "NNN"   (required),
 *   "status":           "..."   (required target status),
 *   "comment":          "..."   (optional; REQUIRED when the transition
 *                                requires_comment),
 *   "markdown_enabled": bool     (optional, applies to the comment)
 * }
 * Response: {success:true, ticket_id, status}
 *
 * Mirrors api/update_ticket.php: workflow validation, requires_comment
 * enforcement, updateTicket (updated_by/updated_at + closed_at handling), Matrix
 * status-change notification, and StatsModel cache invalidation. When a comment
 * is supplied it is posted first (per-key label) so "close with reason" is one call.
 */

header('Content-Type: application/json');

error_reporting(E_ALL);
ini_set('display_errors', 0);

require_once dirname(__DIR__) . '/middleware/RateLimitMiddleware.php';
RateLimitMiddleware::apply('api');

require_once dirname(__DIR__) . '/config/config.php';
require_once dirname(__DIR__) . '/helpers/Database.php';
require_once dirname(__DIR__) . '/middleware/ApiKeyAuth.php';
require_once dirname(__DIR__) . '/models/TicketModel.php';
require_once dirname(__DIR__) . '/models/CommentModel.php';
require_once dirname(__DIR__) . '/models/WorkflowModel.php';
require_once dirname(__DIR__) . '/models/AuditLogModel.php';
require_once dirname(__DIR__) . '/models/StatsModel.php';
require_once dirname(__DIR__) . '/helpers/NotificationHelper.php';

try {
    $conn = Database::getConnection();
} catch (Throwable $e) {
    error_log('ticket_status_api: DB connection failed: ' . $e->getMessage());
    http_response_code(500);
    echo json_encode(['success' => false, 'error' => 'Internal server error']);
    exit;
}

$apiKeyAuth = new ApiKeyAuth($conn);

try {
    $apiKeyAuth->authenticate();
} catch (Exception $e) {
    // ApiKeyAuth already sent the 401 response.
    exit;
}

// Changing status is a write — reject 'read' keys with 403 before any mutation.
$apiKeyAuth->requireScope('read_write');

if ($_SERVER['REQUEST_METHOD'] !== 'POST') {
    http_response_code(405);
    echo json_encode(['success' => false, 'error' => 'Method not allowed. Use POST.']);
    exit;
}

$context = $apiKeyAuth->getKeyContext();
$keyName = $context['key_name'] ?? 'API';
$createdBy = ($context['created_by'] ?? null) !== null ? (int)$context['created_by'] : null;

$rawInput = file_get_contents('php://input');
$data = json_decode($rawInput, true);
if (!is_array($data)) {
    http_response_code(400);
    echo json_encode(['success' => false, 'error' => 'Invalid JSON body']);
    exit;
}

$ticketId = isset($data['ticket_id']) ? trim((string)$data['ticket_id']) : '';
if ($ticketId === '') {
    http_response_code(400);
    echo json_encode(['success' => false, 'error' => 'ticket_id is required']);
    exit;
}

$newStatus = isset($data['status']) ? trim((string)$data['status']) : '';
if ($newStatus === '') {
    http_response_code(400);
    echo json_encode(['success' => false, 'error' => 'status is required']);
    exit;
}

$comment = isset($data['comment']) ? trim((string)$data['comment']) : '';

// Validate the ticket exists.
$ticketModel = new TicketModel($conn);
$ticket = $ticketModel->getTicketById($ticketId);
if (!$ticket) {
    http_response_code(404);
    echo json_encode(['success' => false, 'error' => 'Ticket not found']);
    exit;
}

$currentStatus = (string)$ticket['status'];

// Validate the transition (API key is never admin).
$workflowModel = new WorkflowModel($conn);
if (!$workflowModel->isTransitionAllowed($currentStatus, $newStatus, false)) {
    http_response_code(400);
    echo json_encode([
        'success' => false,
        'error' => 'Status transition not allowed: ' . $currentStatus . ' -> ' . $newStatus,
    ]);
    exit;
}

// Enforce requires_comment transitions server-side.
if ($workflowModel->transitionRequiresComment($currentStatus, $newStatus) && $comment === '') {
    http_response_code(400);
    echo json_encode([
        'success' => false,
        'error' => 'A comment is required for this status change',
        'requires_comment' => true,
    ]);
    exit;
}

// Post the comment first (per-key label) so a close-with-reason is one call.
if ($comment !== '') {
    $commentModel = new CommentModel($conn);
    $commentResult = $commentModel->addComment($ticketId, [
        'user_name' => $keyName,
        'comment_text' => $comment,
        'markdown_enabled' => !empty($data['markdown_enabled']),
    ], $createdBy);
    if (empty($commentResult['success'])) {
        error_log('ticket_status_api: addComment failed for ticket ' . $ticketId
            . ': ' . ($commentResult['error'] ?? 'unknown'));
        http_response_code(500);
        echo json_encode(['success' => false, 'error' => 'Failed to add comment']);
        exit;
    }
}

// Apply the status change. updateTicket sets updated_by/updated_at and handles
// closed_at (set on close, cleared on reopen) via its own SQL.
$updateData = [
    'ticket_id' => $ticketId,
    'title' => $ticket['title'],
    'description' => $ticket['description'],
    'category' => $ticket['category'],
    'type' => $ticket['type'],
    'status' => $newStatus,
    'priority' => (int)$ticket['priority'],
];

$updateResult = $ticketModel->updateTicket($updateData, $createdBy);
if (empty($updateResult['success'])) {
    error_log('ticket_status_api: updateTicket failed for ticket ' . $ticketId
        . ': ' . ($updateResult['error'] ?? 'unknown'));
    http_response_code(500);
    echo json_encode(['success' => false, 'error' => 'Failed to update ticket status']);
    exit;
}

// Notify, audit, and refresh stats only when the status actually changed.
if ($currentStatus !== $newStatus) {
    NotificationHelper::sendStatusChangeNotification(
        $ticketId,
        $currentStatus,
        $newStatus,
        (string)$ticket['title'],
        $keyName
    );
    NotificationHelper::notifyWatchers(
        $conn,
        $ticketId,
        (string)$ticket['title'],
        'status_changed',
        ['old_status' => $currentStatus, 'new_status' => $newStatus, 'changed_by' => $keyName],
        $createdBy,
        $ticket['visibility'] ?? 'public'
    );

    // Audit trail (action 'update' / entity 'ticket' are both whitelisted).
    $auditLog = new AuditLogModel($conn);
    $auditLog->log($createdBy, 'update', 'ticket', $ticketId, [
        'status' => ['from' => $currentStatus, 'to' => $newStatus],
        'key_name' => $keyName,
        'via_api' => true,
    ]);

    // Status change is a ticket-state change — refresh dashboard stats.
    (new StatsModel($conn))->invalidateCache();
}

echo json_encode([
    'success' => true,
    'ticket_id' => $ticketId,
    'status' => $newStatus,
]);
exit;