From 6d4662aa9821ba911314eb0fe8147b84fbae7cd0 Mon Sep 17 00:00:00 2001
From: eelke <eelke@eelkeklein.nl>
Date: Mon, 25 Dec 2017 15:32:02 +0100
Subject: [PATCH] Added WorkManager to manage background tasks.

Relies heavily on the QThreadPool.
---
 core/WorkManager.cpp | 47 ++++++++++++++++++++++++++++++++++++++++++++
 core/WorkManager.h   | 20 +++++++++++++++++++
 core/core.pro        |  6 ++++--
 3 files changed, 71 insertions(+), 2 deletions(-)
 create mode 100644 core/WorkManager.cpp
 create mode 100644 core/WorkManager.h

diff --git a/core/WorkManager.cpp b/core/WorkManager.cpp
new file mode 100644
index 0000000..12d7a0a
--- /dev/null
+++ b/core/WorkManager.cpp
@@ -0,0 +1,47 @@
+#include "WorkManager.h"
+
+#include <QRunnable.h>
+#include <QThreadPool.h>
+#include <deque>
+#include <functional>
+#include <mutex>
+
+
+class WorkManagerImpl: public WorkManager {
+public:
+	virtual void addRunnable(QRunnable *runnable) override;
+	virtual void addWork(Work work) override;
+};
+
+
+
+std::shared_ptr<WorkManager> WorkManager::getWorkManager()
+{
+	static std::shared_ptr<WorkManager> wm = std::make_shared<WorkManagerImpl>();
+	return wm;
+}
+
+void WorkManagerImpl::addRunnable(QRunnable *runnable)
+{
+	auto tp = QThreadPool::globalInstance();
+	tp->start(runnable);
+}
+
+class CallableTask : public QRunnable {
+public:
+	CallableTask(WorkManager::Work &&w)
+		: work(std::move(w))
+	{}
+protected:
+	void run()
+	{
+		work();
+	}
+private:
+	WorkManager::Work work;
+};
+
+void WorkManagerImpl::addWork(Work work)
+{
+	addRunnable(new CallableTask(std::move(work)));
+}
diff --git a/core/WorkManager.h b/core/WorkManager.h
new file mode 100644
index 0000000..28780ae
--- /dev/null
+++ b/core/WorkManager.h
@@ -0,0 +1,20 @@
+#ifndef WORKMANAGER_H
+#define WORKMANAGER_H
+
+#include <functional>
+#include <memory>
+
+class QRunnable;
+
+class WorkManager {
+public:
+
+	static std::shared_ptr<WorkManager> getWorkManager();
+
+	using Work = std::function<void()>;
+	virtual void addRunnable(QRunnable *runnable) = 0;
+	virtual void addWork(Work work) = 0;
+
+};
+
+#endif // WORKMANAGER_H
diff --git a/core/core.pro b/core/core.pro
index bbc84b9..fcf9077 100644
--- a/core/core.pro
+++ b/core/core.pro
@@ -38,7 +38,8 @@ SOURCES += my_boost_assert_handler.cpp \
     BackupFormatModel.cpp \
 	QueuedBackgroundTask.cpp \
     ExplainTreeModelItem.cpp \
-    jsoncpp.cpp
+    jsoncpp.cpp \
+    WorkManager.cpp
 
 HEADERS += PasswordManager.h \
     SqlLexer.h \
@@ -48,7 +49,8 @@ HEADERS += PasswordManager.h \
 	QueuedBackgroundTask.h \
 	Expected.h \
     ExplainTreeModelItem.h \
-    json/json.h
+    json/json.h \
+    WorkManager.h
 	
 unix {
     target.path = /usr/lib