Continues migration with DDS, Common

Lts/Common/LtsUtils/LtsUtilsCore/promise.cpp

@@ -0,0 +1,103 @@
+
+
+
+#include "promise.h"
+
+#include <QTimer>
+
+namespace LtsUtils
+{
+
+Promise::Promise(const std::function<void(ResultFunction resolve, ResultFunction reject)> &function, QObject *parent)
+  : QObject(parent)
+  , m_functionAlreadySet(false)
+  , m_timeout(new QTimer(this))
+  , m_resultSet(false)
+  , m_timeoutSet(false)
+{
+  m_timeout->setSingleShot(true);
+  connect(m_timeout, &QTimer::timeout,
+          this, &Promise::slotTimeout);
+  setFunction(function);
+}
+
+
+void Promise::setFunction(const std::function<void(ResultFunction resolve, ResultFunction reject)> &function)
+{
+  if (!function || m_functionAlreadySet)
+    return;
+
+  m_functionAlreadySet = true;
+
+  if (m_timeoutSet)
+    m_timeout->start();
+
+  
+  QTimer::singleShot(0, this, [this, function]()
+  {
+    
+    function([this](const QVariant &value)
+    { 
+      resolve(value);
+    }, [this](const QVariant &value)
+    {
+      
+      reject(value);
+    });
+  });
+}
+
+
+void Promise::setTimeout(int interval)
+{
+  m_timeout->stop();
+  m_timeout->setInterval(interval);
+  m_timeoutSet = (interval != 0);
+
+  if (interval != 0 && m_functionAlreadySet)
+    m_timeout->start();
+}
+
+
+void Promise::slotTimeout()
+{
+  reject(QStringLiteral("timeout"));
+}
+
+
+void Promise::resolve(const QVariant &value)
+{
+  if (m_resultSet)
+    return;
+  m_resultSet = true;
+
+  m_timeout->stop();
+  m_resolveFn(value);
+}
+
+
+void Promise::reject(const QVariant &value)
+{
+  if (m_resultSet)
+    return;
+  m_resultSet = true;
+
+  m_timeout->stop();
+  m_rejectFn(value);
+}
+
+
+Promise &Promise::resolved(ResultFunction resolveFn)
+{
+  m_resolveFn = resolveFn;
+  return *this;
+}
+
+
+Promise &Promise::rejected(ResultFunction rejectFn)
+{
+  m_rejectFn = rejectFn;
+  return *this;
+}
+
+}