qt-migration-legatus/qt6-after/qt6-migrated-legatus/Lts/Common/LtsRestClient/lts_rest_client.cpp

/**
 * Lightweight REST Client Framework
 * $Id$
 * $HeadURL$
 * $Author$
 * Created by Hannes Fritsche, ESZS, 2026-08-21
 */

#include "lts_rest_client.h"
#include <QTimer>
#include <QUrl>
#include <QtNetwork/QNetworkAccessManager>
#include <QtNetwork/QNetworkReply>
#include <QtNetwork/QNetworkRequest>

namespace LtsCommon
{

  LtsRestClient::LtsRestClient(const QString &baseUrl, QObject *parent)
      : QObject(parent)
      , m_baseUrl(baseUrl)
      , m_manager(new QNetworkAccessManager(this))
  {
  }

  void LtsRestClient::ping(PingSuccessCallback onSuccess, ErrorCallback onError, int timeoutMs)
  {
    const QNetworkRequest request((QUrl(m_baseUrl)));
    QNetworkReply *reply = m_manager->head(request);

    if (!reply)
    {
      if (onError)
        onError(QStringLiteral("Failed to initiate ping."));

      return;
    }

    // 1. Setup the timer (parented to reply for auto-cleanup)
    QTimer *timeoutTimer = new QTimer(reply);
    timeoutTimer->setSingleShot(true);

    // 2. Connect the timeout signal to abort the request
    connect(timeoutTimer,
            &QTimer::timeout,
            this,
            [reply]()
            {
              if (reply && reply->isRunning())
                reply->abort(); // Triggers finished() with OperationCanceledError
            });

    // 3. Connect the finished signal to handle the response
    connect(reply,
            &QNetworkReply::finished,
            this,
            [reply, timeoutTimer, onSuccess, onError]()
            {
              timeoutTimer->stop();
              reply->deleteLater();

              if (reply->error() != QNetworkReply::NoError)
              {
                if (onError)
                {
                  if (reply->error() == QNetworkReply::OperationCanceledError)
                    onError(QStringLiteral("Ping timed out."));
                  else
                    onError(reply->errorString());
                }

                return;
              }

              const int statusCode = reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt();

              if (onSuccess)
                onSuccess(statusCode);
            });

    // 4. Start the timer only after all connections are successfully established
    timeoutTimer->start(timeoutMs);
  }

  void LtsRestClient::get(const QString &endpoint, SuccessCallback onSuccess, ErrorCallback onError)
  {
    sendRequest(QStringLiteral("GET"), endpoint, QByteArray(), onSuccess, onError);
  }

  void LtsRestClient::post(const QString &endpoint, const QJsonDocument &json, SuccessCallback onSuccess, ErrorCallback onError)
  {
    sendRequest(QStringLiteral("POST"), endpoint, json.toJson(), onSuccess, onError);
  }

  void LtsRestClient::put(const QString &endpoint, const QJsonDocument &json, SuccessCallback onSuccess, ErrorCallback onError)
  {
    sendRequest(QStringLiteral("PUT"), endpoint, json.toJson(), onSuccess, onError);
  }

  void LtsRestClient::del(const QString &endpoint, SuccessCallback onSuccess, ErrorCallback onError)
  {
    sendRequest(QStringLiteral("DELETE"), endpoint, QByteArray(), onSuccess, onError);
  }

  void LtsRestClient::sendRequest(const QString &method, const QString &endpoint, const QByteArray &data, SuccessCallback onSuccess, ErrorCallback onError)
  {
    QUrl url(m_baseUrl);
    url.setPath(url.path() + endpoint);

    QNetworkRequest request(url);
    request.setHeader(QNetworkRequest::ContentTypeHeader, QStringLiteral("application/json"));

    QNetworkReply *reply = nullptr;

    if (method == QStringLiteral("GET"))
      reply = m_manager->get(request);
    else if (method == QStringLiteral("POST"))
      reply = m_manager->post(request, data);
    else if (method == QStringLiteral("PUT"))
      reply = m_manager->put(request, data);
    else if (method == QStringLiteral("DELETE"))
      reply = m_manager->deleteResource(request);

    if (!reply)
    {
      if (onError)
        onError(QStringLiteral("Failed to initiate request."));

      return;
    }

    connect(reply,
            &QNetworkReply::finished,
            this,
            [reply, onSuccess, onError]()
            {
              reply->deleteLater();

              // Handle network errors
              if (reply->error() != QNetworkReply::NoError)
              {
                if (onError)
                  onError(reply->errorString());

                return;
              }

              // Handle HTTP errors
              const int statusCode = reply->attribute(QNetworkRequest::HttpStatusCodeAttribute).toInt();
              if (statusCode >= 400)
              {
                if (onError)
                  onError(QStringLiteral("HTTP Error %1").arg(statusCode));

                return;
              }

              // Parse JSON safely
              QJsonParseError parseError;
              const QJsonDocument doc = QJsonDocument::fromJson(reply->readAll(), &parseError);

              if (parseError.error != QJsonParseError::NoError)
              {
                if (onError)
                  onError(QStringLiteral("JSON Parse Error: ") + parseError.errorString());

                return;
              }

              if (onSuccess)
                onSuccess(doc);
            });
  }

} // namespace LtsCommon