feat: add ConcurrentTask

This tasks (or rather, meta-task) has the ability to run several other
sub tasks concurrently.

Signed-off-by: flow <flowlnlnln@gmail.com>

2 files changed, 202 insertions, 0 deletions

diff --git a/launcher/tasks/ConcurrentTask.cpp b/launcher/tasks/ConcurrentTask.cpp
new file mode 100644
index 00000000..b88cfb13
--- /dev/null
+++ b/launcher/tasks/ConcurrentTask.cpp
@@ -0,0 +1,144 @@
+#include "ConcurrentTask.h"
+
+#include <QDebug>
+
+ConcurrentTask::ConcurrentTask(QObject* parent, QString task_name, int max_concurrent)
+    : Task(parent), m_name(task_name), m_total_max_size(max_concurrent)
+{}
+
+ConcurrentTask::~ConcurrentTask()
+{
+    for (auto task : m_queue) {
+        if (task)
+            task->deleteLater();
+    }
+}
+
+auto ConcurrentTask::getStepProgress() const -> qint64
+{
+    return m_stepProgress;
+}
+
+auto ConcurrentTask::getStepTotalProgress() const -> qint64
+{
+    return m_stepTotalProgress;
+}
+
+void ConcurrentTask::addTask(Task::Ptr task)
+{
+    if (!isRunning())
+        m_queue.append(task);
+    else
+        qWarning() << "Tried to add a task to a running concurrent task!";
+}
+
+void ConcurrentTask::executeTask()
+{
+    m_total_size = m_queue.size();
+
+    for (int i = 0; i < m_total_max_size; i++)
+        startNext();
+}
+
+bool ConcurrentTask::abort()
+{
+    if (m_doing.isEmpty()) {
+        // Don't call emitAborted() here, we want to bypass the 'is the task running' check
+        emit aborted();
+        emit finished();
+
+        m_aborted = true;
+        return true;
+    }
+
+    m_queue.clear();
+
+    m_aborted = true;
+    for (auto task : m_doing)
+        m_aborted &= task->abort();
+
+    if (m_aborted)
+        emitAborted();
+
+    return m_aborted;
+}
+
+void ConcurrentTask::startNext()
+{
+    if (m_aborted || m_doing.count() > m_total_max_size)
+        return;
+
+    if (m_queue.isEmpty() && m_doing.isEmpty()) {
+        emitSucceeded();
+        return;
+    }
+
+    if (m_queue.isEmpty())
+        return;
+
+    Task::Ptr next = m_queue.dequeue();
+
+    connect(next.get(), &Task::succeeded, this, [this, next] { subTaskSucceeded(next); });
+    connect(next.get(), &Task::failed, this, [this, next](QString msg) { subTaskFailed(next, msg); });
+
+    connect(next.get(), &Task::status, this, &ConcurrentTask::subTaskStatus);
+    connect(next.get(), &Task::stepStatus, this, &ConcurrentTask::subTaskStatus);
+
+    connect(next.get(), &Task::progress, this, &ConcurrentTask::subTaskProgress);
+
+    m_doing.insert(next.get(), next);
+
+    setStepStatus(next->isMultiStep() ? next->getStepStatus() : next->getStatus());
+    updateState();
+
+    next->start();
+}
+
+void ConcurrentTask::subTaskSucceeded(Task::Ptr task)
+{
+    m_done.insert(task.get(), task);
+    m_doing.remove(task.get());
+
+    disconnect(task.get(), 0, this, 0);
+
+    updateState();
+
+    startNext();
+}
+
+void ConcurrentTask::subTaskFailed(Task::Ptr task, const QString& msg)
+{
+    m_done.insert(task.get(), task);
+    m_failed.insert(task.get(), task);
+
+    m_doing.remove(task.get());
+
+    disconnect(task.get(), 0, this, 0);
+
+    updateState();
+
+    startNext();
+}
+
+void ConcurrentTask::subTaskStatus(const QString& msg)
+{
+    setStepStatus(msg);
+}
+
+void ConcurrentTask::subTaskProgress(qint64 current, qint64 total)
+{
+    if (total == 0) {
+        setProgress(0, 100);
+        return;
+    }
+
+    m_stepProgress = current;
+    m_stepTotalProgress = total;
+}
+
+void ConcurrentTask::updateState()
+{
+    setProgress(m_done.count(), m_total_size);
+    setStatus(tr("Executing %1 task(s) (%2 out of %3 are done)")
+                  .arg(QString::number(m_doing.count()), QString::number(m_done.count()), QString::number(m_total_size)));
+}
diff --git a/launcher/tasks/ConcurrentTask.h b/launcher/tasks/ConcurrentTask.h
new file mode 100644
index 00000000..5898899d
--- /dev/null
+++ b/launcher/tasks/ConcurrentTask.h
@@ -0,0 +1,58 @@
+#pragma once
+
+#include <QQueue>
+#include <QSet>
+
+#include "tasks/Task.h"
+
+class ConcurrentTask : public Task {
+    Q_OBJECT
+public:
+    explicit ConcurrentTask(QObject* parent = nullptr, QString task_name = "", int max_concurrent = 6);
+    virtual ~ConcurrentTask();
+
+    inline auto isMultiStep() const -> bool override { return m_queue.size() > 1; };
+    auto getStepProgress() const -> qint64 override;
+    auto getStepTotalProgress() const -> qint64 override;
+
+    inline auto getStepStatus() const -> QString override { return m_step_status; }
+
+    void addTask(Task::Ptr task);
+
+public slots:
+    bool abort() override;
+
+protected
+slots:
+    void executeTask() override;
+
+    virtual void startNext();
+
+    void subTaskSucceeded(Task::Ptr);
+    void subTaskFailed(Task::Ptr, const QString &msg);
+    void subTaskStatus(const QString &msg);
+    void subTaskProgress(qint64 current, qint64 total);
+
+protected:
+    void setStepStatus(QString status) { m_step_status = status; emit stepStatus(status); };
+
+    virtual void updateState();
+
+protected:
+    QString m_name;
+    QString m_step_status;
+
+    QQueue<Task::Ptr> m_queue;
+
+    QHash<Task*, Task::Ptr> m_doing;
+    QHash<Task*, Task::Ptr> m_done;
+    QHash<Task*, Task::Ptr> m_failed;
+
+    int m_total_max_size;
+    int m_total_size;
+
+    qint64 m_stepProgress = 0;
+    qint64 m_stepTotalProgress = 100;
+
+    bool m_aborted = false;
+};