NOISSUE Flatten gui and logic libraries into MultiMC

16 files changed, 1295 insertions, 0 deletions

diff --git a/launcher/launch/LaunchStep.cpp b/launcher/launch/LaunchStep.cpp
new file mode 100644
index 00000000..d6bb6e88
--- /dev/null
+++ b/launcher/launch/LaunchStep.cpp
@@ -0,0 +1,27 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "LaunchStep.h"
+#include "LaunchTask.h"
+
+void LaunchStep::bind(LaunchTask *parent)
+{
+    m_parent = parent;
+    connect(this, &LaunchStep::readyForLaunch, parent, &LaunchTask::onReadyForLaunch);
+    connect(this, &LaunchStep::logLine, parent, &LaunchTask::onLogLine);
+    connect(this, &LaunchStep::logLines, parent, &LaunchTask::onLogLines);
+    connect(this, &LaunchStep::finished, parent, &LaunchTask::onStepFinished);
+    connect(this, &LaunchStep::progressReportingRequest, parent, &LaunchTask::onProgressReportingRequested);
+}
diff --git a/launcher/launch/LaunchStep.h b/launcher/launch/LaunchStep.h
new file mode 100644
index 00000000..3939f960
--- /dev/null
+++ b/launcher/launch/LaunchStep.h
@@ -0,0 +1,50 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "tasks/Task.h"
+#include "MessageLevel.h"
+
+#include <QStringList>
+
+class LaunchTask;
+class LaunchStep: public Task
+{
+    Q_OBJECT
+public: /* methods */
+    explicit LaunchStep(LaunchTask *parent):Task(nullptr), m_parent(parent)
+    {
+        bind(parent);
+    };
+    virtual ~LaunchStep() {};
+
+private: /* methods */
+    void bind(LaunchTask *parent);
+
+signals:
+    void logLines(QStringList lines, MessageLevel::Enum level);
+    void logLine(QString line, MessageLevel::Enum level);
+    void readyForLaunch();
+    void progressReportingRequest();
+
+public slots:
+    virtual void proceed() {};
+    // called in the opposite order than the Task launch(), used to clean up or otherwise undo things after the launch ends
+    virtual void finalize() {};
+
+protected: /* data */
+    LaunchTask *m_parent;
+};
diff --git a/launcher/launch/LaunchTask.cpp b/launcher/launch/LaunchTask.cpp
new file mode 100644
index 00000000..e6f6bbac
--- /dev/null
+++ b/launcher/launch/LaunchTask.cpp
@@ -0,0 +1,280 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Authors: Orochimarufan <orochimarufan.x3@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "launch/LaunchTask.h"
+#include "MessageLevel.h"
+#include "MMCStrings.h"
+#include "java/JavaChecker.h"
+#include "tasks/Task.h"
+#include <QDebug>
+#include <QDir>
+#include <QEventLoop>
+#include <QRegularExpression>
+#include <QCoreApplication>
+#include <QStandardPaths>
+#include <assert.h>
+
+void LaunchTask::init()
+{
+    m_instance->setRunning(true);
+}
+
+shared_qobject_ptr<LaunchTask> LaunchTask::create(InstancePtr inst)
+{
+    shared_qobject_ptr<LaunchTask> proc(new LaunchTask(inst));
+    proc->init();
+    return proc;
+}
+
+LaunchTask::LaunchTask(InstancePtr instance): m_instance(instance)
+{
+}
+
+void LaunchTask::appendStep(shared_qobject_ptr<LaunchStep> step)
+{
+    m_steps.append(step);
+}
+
+void LaunchTask::prependStep(shared_qobject_ptr<LaunchStep> step)
+{
+    m_steps.prepend(step);
+}
+
+void LaunchTask::executeTask()
+{
+    m_instance->setCrashed(false);
+    if(!m_steps.size())
+    {
+        state = LaunchTask::Finished;
+        emitSucceeded();
+    }
+    state = LaunchTask::Running;
+    onStepFinished();
+}
+
+void LaunchTask::onReadyForLaunch()
+{
+    state = LaunchTask::Waiting;
+    emit readyForLaunch();
+}
+
+void LaunchTask::onStepFinished()
+{
+    // initial -> just start the first step
+    if(currentStep == -1)
+    {
+        currentStep ++;
+        m_steps[currentStep]->start();
+        return;
+    }
+
+    auto step = m_steps[currentStep];
+    if(step->wasSuccessful())
+    {
+        // end?
+        if(currentStep == m_steps.size() - 1)
+        {
+            finalizeSteps(true, QString());
+        }
+        else
+        {
+            currentStep ++;
+            step = m_steps[currentStep];
+            step->start();
+        }
+    }
+    else
+    {
+        finalizeSteps(false, step->failReason());
+    }
+}
+
+void LaunchTask::finalizeSteps(bool successful, const QString& error)
+{
+    for(auto step = currentStep; step >= 0; step--)
+    {
+        m_steps[step]->finalize();
+    }
+    if(successful)
+    {
+        emitSucceeded();
+    }
+    else
+    {
+        emitFailed(error);
+    }
+}
+
+void LaunchTask::onProgressReportingRequested()
+{
+    state = LaunchTask::Waiting;
+    emit requestProgress(m_steps[currentStep].get());
+}
+
+void LaunchTask::setCensorFilter(QMap<QString, QString> filter)
+{
+    m_censorFilter = filter;
+}
+
+QString LaunchTask::censorPrivateInfo(QString in)
+{
+    auto iter = m_censorFilter.begin();
+    while (iter != m_censorFilter.end())
+    {
+        in.replace(iter.key(), iter.value());
+        iter++;
+    }
+    return in;
+}
+
+void LaunchTask::proceed()
+{
+    if(state != LaunchTask::Waiting)
+    {
+        return;
+    }
+    m_steps[currentStep]->proceed();
+}
+
+bool LaunchTask::canAbort() const
+{
+    switch(state)
+    {
+        case LaunchTask::Aborted:
+        case LaunchTask::Failed:
+        case LaunchTask::Finished:
+            return false;
+        case LaunchTask::NotStarted:
+            return true;
+        case LaunchTask::Running:
+        case LaunchTask::Waiting:
+        {
+            auto step = m_steps[currentStep];
+            return step->canAbort();
+        }
+    }
+    return false;
+}
+
+bool LaunchTask::abort()
+{
+    switch(state)
+    {
+        case LaunchTask::Aborted:
+        case LaunchTask::Failed:
+        case LaunchTask::Finished:
+            return true;
+        case LaunchTask::NotStarted:
+        {
+            state = LaunchTask::Aborted;
+            emitFailed("Aborted");
+            return true;
+        }
+        case LaunchTask::Running:
+        case LaunchTask::Waiting:
+        {
+            auto step = m_steps[currentStep];
+            if(!step->canAbort())
+            {
+                return false;
+            }
+            if(step->abort())
+            {
+                state = LaunchTask::Aborted;
+                return true;
+            }
+        }
+        default:
+            break;
+    }
+    return false;
+}
+
+shared_qobject_ptr<LogModel> LaunchTask::getLogModel()
+{
+    if(!m_logModel)
+    {
+        m_logModel.reset(new LogModel());
+        m_logModel->setMaxLines(m_instance->getConsoleMaxLines());
+        m_logModel->setStopOnOverflow(m_instance->shouldStopOnConsoleOverflow());
+        // FIXME: should this really be here?
+        m_logModel->setOverflowMessage(tr("MultiMC stopped watching the game log because the log length surpassed %1 lines.\n"
+            "You may have to fix your mods because the game is still logging to files and"
+            " likely wasting harddrive space at an alarming rate!").arg(m_logModel->getMaxLines()));
+    }
+    return m_logModel;
+}
+
+void LaunchTask::onLogLines(const QStringList &lines, MessageLevel::Enum defaultLevel)
+{
+    for (auto & line: lines)
+    {
+        onLogLine(line, defaultLevel);
+    }
+}
+
+void LaunchTask::onLogLine(QString line, MessageLevel::Enum level)
+{
+    // if the launcher part set a log level, use it
+    auto innerLevel = MessageLevel::fromLine(line);
+    if(innerLevel != MessageLevel::Unknown)
+    {
+        level = innerLevel;
+    }
+
+    // If the level is still undetermined, guess level
+    if (level == MessageLevel::StdErr || level == MessageLevel::StdOut || level == MessageLevel::Unknown)
+    {
+        level = m_instance->guessLevel(line, level);
+    }
+
+    // censor private user info
+    line = censorPrivateInfo(line);
+
+    auto &model = *getLogModel();
+    model.append(level, line);
+}
+
+void LaunchTask::emitSucceeded()
+{
+    m_instance->setRunning(false);
+    Task::emitSucceeded();
+}
+
+void LaunchTask::emitFailed(QString reason)
+{
+    m_instance->setRunning(false);
+    m_instance->setCrashed(true);
+    Task::emitFailed(reason);
+}
+
+QString LaunchTask::substituteVariables(const QString &cmd) const
+{
+    QString out = cmd;
+    auto variables = m_instance->getVariables();
+    for (auto it = variables.begin(); it != variables.end(); ++it)
+    {
+        out.replace("$" + it.key(), it.value());
+    }
+    auto env = QProcessEnvironment::systemEnvironment();
+    for (auto var : env.keys())
+    {
+        out.replace("$" + var, env.value(var));
+    }
+    return out;
+}
+
diff --git a/launcher/launch/LaunchTask.h b/launcher/launch/LaunchTask.h
new file mode 100644
index 00000000..ae81462f
--- /dev/null
+++ b/launcher/launch/LaunchTask.h
@@ -0,0 +1,123 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Authors: Orochimarufan <orochimarufan.x3@gmail.com>
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+#include <QProcess>
+#include <QObjectPtr.h>
+#include "LogModel.h"
+#include "BaseInstance.h"
+#include "MessageLevel.h"
+#include "LoggedProcess.h"
+#include "LaunchStep.h"
+
+class LaunchTask: public Task
+{
+    Q_OBJECT
+protected:
+    explicit LaunchTask(InstancePtr instance);
+    void init();
+
+public:
+    enum State
+    {
+        NotStarted,
+        Running,
+        Waiting,
+        Failed,
+        Aborted,
+        Finished
+    };
+
+public: /* methods */
+    static shared_qobject_ptr<LaunchTask> create(InstancePtr inst);
+    virtual ~LaunchTask() {};
+
+    void appendStep(shared_qobject_ptr<LaunchStep> step);
+    void prependStep(shared_qobject_ptr<LaunchStep> step);
+    void setCensorFilter(QMap<QString, QString> filter);
+
+    InstancePtr instance()
+    {
+        return m_instance;
+    }
+
+    void setPid(qint64 pid)
+    {
+        m_pid = pid;
+    }
+
+    qint64 pid()
+    {
+        return m_pid;
+    }
+
+    /**
+     * @brief prepare the process for launch (for multi-stage launch)
+     */
+    virtual void executeTask() override;
+
+    /**
+     * @brief launch the armed instance
+     */
+    void proceed();
+
+    /**
+     * @brief abort launch
+     */
+    bool abort() override;
+
+    bool canAbort() const override;
+
+    shared_qobject_ptr<LogModel> getLogModel();
+
+public:
+    QString substituteVariables(const QString &cmd) const;
+    QString censorPrivateInfo(QString in);
+
+protected: /* methods */
+    virtual void emitFailed(QString reason) override;
+    virtual void emitSucceeded() override;
+
+signals:
+    /**
+     * @brief emitted when the launch preparations are done
+     */
+    void readyForLaunch();
+
+    void requestProgress(Task *task);
+
+    void requestLogging();
+
+public slots:
+    void onLogLines(const QStringList& lines, MessageLevel::Enum defaultLevel = MessageLevel::MultiMC);
+    void onLogLine(QString line, MessageLevel::Enum defaultLevel = MessageLevel::MultiMC);
+    void onReadyForLaunch();
+    void onStepFinished();
+    void onProgressReportingRequested();
+
+private: /*methods */
+    void finalizeSteps(bool successful, const QString & error);
+
+protected: /* data */
+    InstancePtr m_instance;
+    shared_qobject_ptr<LogModel> m_logModel;
+    QList <shared_qobject_ptr<LaunchStep>> m_steps;
+    QMap<QString, QString> m_censorFilter;
+    int currentStep = -1;
+    State state = NotStarted;
+    qint64 m_pid = -1;
+};
diff --git a/launcher/launch/LogModel.cpp b/launcher/launch/LogModel.cpp
new file mode 100644
index 00000000..92f9487a
--- /dev/null
+++ b/launcher/launch/LogModel.cpp
@@ -0,0 +1,167 @@
+#include "LogModel.h"
+
+LogModel::LogModel(QObject *parent):QAbstractListModel(parent)
+{
+    m_content.resize(m_maxLines);
+}
+
+int LogModel::rowCount(const QModelIndex &parent) const
+{
+    if (parent.isValid())
+        return 0;
+
+    return m_numLines;
+}
+
+QVariant LogModel::data(const QModelIndex &index, int role) const
+{
+    if (index.row() < 0 || index.row() >= m_numLines)
+        return QVariant();
+
+    auto row = index.row();
+    auto realRow = (row + m_firstLine) % m_maxLines;
+    if (role == Qt::DisplayRole || role == Qt::EditRole)
+    {
+        return m_content[realRow].line;
+    }
+    if(role == LevelRole)
+    {
+        return m_content[realRow].level;
+    }
+
+    return QVariant();
+}
+
+void LogModel::append(MessageLevel::Enum level, QString line)
+{
+    if(m_suspended)
+    {
+        return;
+    }
+    int lineNum = (m_firstLine + m_numLines) % m_maxLines;
+    // overflow
+    if(m_numLines == m_maxLines)
+    {
+        if(m_stopOnOverflow)
+        {
+            // nothing more to do, the buffer is full
+            return;
+        }
+        beginRemoveRows(QModelIndex(), 0, 0);
+        m_firstLine = (m_firstLine + 1) % m_maxLines;
+        m_numLines --;
+        endRemoveRows();
+    }
+    else if (m_numLines == m_maxLines - 1 && m_stopOnOverflow)
+    {
+        level = MessageLevel::Fatal;
+        line = m_overflowMessage;
+    }
+    beginInsertRows(QModelIndex(), m_numLines, m_numLines);
+    m_numLines ++;
+    m_content[lineNum].level = level;
+    m_content[lineNum].line = line;
+    endInsertRows();
+}
+
+void LogModel::suspend(bool suspend)
+{
+    m_suspended = suspend;
+}
+
+bool LogModel::suspended()
+{
+    return m_suspended;
+}
+
+void LogModel::clear()
+{
+    beginResetModel();
+    m_firstLine = 0;
+    m_numLines = 0;
+    endResetModel();
+}
+
+QString LogModel::toPlainText()
+{
+    QString out;
+    out.reserve(m_numLines * 80);
+    for(int i = 0; i < m_numLines; i++)
+    {
+        QString & line = m_content[(m_firstLine + i) % m_maxLines].line;
+        out.append(line + '\n');
+    }
+    out.squeeze();
+    return out;
+}
+
+void LogModel::setMaxLines(int maxLines)
+{
+    // no-op
+    if(maxLines == m_maxLines)
+    {
+        return;
+    }
+    // if it all still fits in the buffer, just resize it
+    if(m_firstLine + m_numLines < m_maxLines)
+    {
+        m_maxLines = maxLines;
+        m_content.resize(maxLines);
+        return;
+    }
+    // otherwise, we need to reorganize the data because it crosses the wrap boundary
+    QVector<entry> newContent;
+    newContent.resize(maxLines);
+    if(m_numLines <= maxLines)
+    {
+        // if it all fits in the new buffer, just copy it over
+        for(int i = 0; i < m_numLines; i++)
+        {
+            newContent[i] = m_content[(m_firstLine + i) % m_maxLines];
+        }
+        m_content.swap(newContent);
+    }
+    else
+    {
+        // if it doesn't fit, part of the data needs to be thrown away (the oldest log messages)
+        int lead = m_numLines - maxLines;
+        beginRemoveRows(QModelIndex(), 0, lead - 1);
+        for(int i = 0; i < maxLines; i++)
+        {
+            newContent[i] = m_content[(m_firstLine + lead + i) % m_maxLines];
+        }
+        m_numLines = m_maxLines;
+        m_content.swap(newContent);
+        endRemoveRows();
+    }
+    m_firstLine = 0;
+    m_maxLines = maxLines;
+}
+
+int LogModel::getMaxLines()
+{
+    return m_maxLines;
+}
+
+void LogModel::setStopOnOverflow(bool stop)
+{
+    m_stopOnOverflow = stop;
+}
+
+void LogModel::setOverflowMessage(const QString& overflowMessage)
+{
+    m_overflowMessage = overflowMessage;
+}
+
+void LogModel::setLineWrap(bool state)
+{
+    if(m_lineWrap != state)
+    {
+        m_lineWrap = state;
+    }
+}
+
+bool LogModel::wrapLines() const
+{
+    return m_lineWrap;
+}
diff --git a/launcher/launch/LogModel.h b/launcher/launch/LogModel.h
new file mode 100644
index 00000000..6aabc823
--- /dev/null
+++ b/launcher/launch/LogModel.h
@@ -0,0 +1,58 @@
+#pragma once
+
+#include <QAbstractListModel>
+#include <QString>
+#include "MessageLevel.h"
+
+class LogModel : public QAbstractListModel
+{
+    Q_OBJECT
+public:
+    explicit LogModel(QObject *parent = 0);
+
+    int rowCount(const QModelIndex &parent = QModelIndex()) const;
+    QVariant data(const QModelIndex &index, int role) const;
+
+    void append(MessageLevel::Enum, QString line);
+    void clear();
+
+    void suspend(bool suspend);
+    bool suspended();
+
+    QString toPlainText();
+
+    int getMaxLines();
+    void setMaxLines(int maxLines);
+    void setStopOnOverflow(bool stop);
+    void setOverflowMessage(const QString & overflowMessage);
+
+    void setLineWrap(bool state);
+    bool wrapLines() const;
+
+    enum Roles
+    {
+        LevelRole = Qt::UserRole
+    };
+
+private /* types */:
+    struct entry
+    {
+        MessageLevel::Enum level;
+        QString line;
+    };
+
+private: /* data */
+    QVector <entry> m_content;
+    int m_maxLines = 1000;
+    // first line in the circular buffer
+    int m_firstLine = 0;
+    // number of lines occupied in the circular buffer
+    int m_numLines = 0;
+    bool m_stopOnOverflow = false;
+    QString m_overflowMessage = "OVERFLOW";
+    bool m_suspended = false;
+    bool m_lineWrap = true;
+
+private:
+    Q_DISABLE_COPY(LogModel)
+};
diff --git a/launcher/launch/steps/LookupServerAddress.cpp b/launcher/launch/steps/LookupServerAddress.cpp
new file mode 100644
index 00000000..de56c28a
--- /dev/null
+++ b/launcher/launch/steps/LookupServerAddress.cpp
@@ -0,0 +1,95 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+
+#include "LookupServerAddress.h"
+
+#include <launch/LaunchTask.h>
+
+LookupServerAddress::LookupServerAddress(LaunchTask *parent) :
+    LaunchStep(parent), m_dnsLookup(new QDnsLookup(this))
+{
+    connect(m_dnsLookup, &QDnsLookup::finished, this, &LookupServerAddress::on_dnsLookupFinished);
+
+    m_dnsLookup->setType(QDnsLookup::SRV);
+}
+
+void LookupServerAddress::setLookupAddress(const QString &lookupAddress)
+{
+    m_lookupAddress = lookupAddress;
+    m_dnsLookup->setName(QString("_minecraft._tcp.%1").arg(lookupAddress));
+}
+
+void LookupServerAddress::setOutputAddressPtr(MinecraftServerTargetPtr output)
+{
+    m_output = std::move(output);
+}
+
+bool LookupServerAddress::abort()
+{
+    m_dnsLookup->abort();
+    emitFailed("Aborted");
+    return true;
+}
+
+void LookupServerAddress::executeTask()
+{
+    m_dnsLookup->lookup();
+}
+
+void LookupServerAddress::on_dnsLookupFinished()
+{
+    if (isFinished())
+    {
+        // Aborted
+        return;
+    }
+
+    if (m_dnsLookup->error() != QDnsLookup::NoError)
+    {
+        emit logLine(QString("Failed to resolve server address (this is NOT an error!) %1: %2\n")
+            .arg(m_dnsLookup->name(), m_dnsLookup->errorString()), MessageLevel::MultiMC);
+        resolve(m_lookupAddress, 25565); // Technically the task failed, however, we don't abort the launch
+                                                      // and leave it up to minecraft to fail (or maybe not) when connecting
+        return;
+    }
+
+    const auto records = m_dnsLookup->serviceRecords();
+    if (records.empty())
+    {
+        emit logLine(
+                QString("Failed to resolve server address %1: the DNS lookup succeeded, but no records were returned.\n")
+                .arg(m_dnsLookup->name()), MessageLevel::Warning);
+        resolve(m_lookupAddress, 25565); // Technically the task failed, however, we don't abort the launch
+                                                      // and leave it up to minecraft to fail (or maybe not) when connecting
+        return;
+    }
+
+    const auto &firstRecord = records.at(0);
+    quint16 port = firstRecord.port();
+
+    emit logLine(QString("Resolved server address %1 to %2 with port %3\n").arg(
+            m_dnsLookup->name(), firstRecord.target(), QString::number(port)),MessageLevel::MultiMC);
+    resolve(firstRecord.target(), port);
+}
+
+void LookupServerAddress::resolve(const QString &address, quint16 port)
+{
+    m_output->address = address;
+    m_output->port = port;
+
+    emitSucceeded();
+    m_dnsLookup->deleteLater();
+}
diff --git a/launcher/launch/steps/LookupServerAddress.h b/launcher/launch/steps/LookupServerAddress.h
new file mode 100644
index 00000000..5a5c3de1
--- /dev/null
+++ b/launcher/launch/steps/LookupServerAddress.h
@@ -0,0 +1,49 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <launch/LaunchStep.h>
+#include <QObjectPtr.h>
+#include <QDnsLookup>
+
+#include "minecraft/launch/MinecraftServerTarget.h"
+
+class LookupServerAddress: public LaunchStep {
+Q_OBJECT
+public:
+    explicit LookupServerAddress(LaunchTask *parent);
+    virtual ~LookupServerAddress() {};
+
+    virtual void executeTask();
+    virtual bool abort();
+    virtual bool canAbort() const
+    {
+        return true;
+    }
+
+    void setLookupAddress(const QString &lookupAddress);
+    void setOutputAddressPtr(MinecraftServerTargetPtr output);
+
+private slots:
+    void on_dnsLookupFinished();
+
+private:
+    void resolve(const QString &address, quint16 port);
+
+    QDnsLookup *m_dnsLookup;
+    QString m_lookupAddress;
+    MinecraftServerTargetPtr m_output;
+};
diff --git a/launcher/launch/steps/PostLaunchCommand.cpp b/launcher/launch/steps/PostLaunchCommand.cpp
new file mode 100644
index 00000000..d48d03d1
--- /dev/null
+++ b/launcher/launch/steps/PostLaunchCommand.cpp
@@ -0,0 +1,84 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "PostLaunchCommand.h"
+#include <launch/LaunchTask.h>
+
+PostLaunchCommand::PostLaunchCommand(LaunchTask *parent) : LaunchStep(parent)
+{
+    auto instance = m_parent->instance();
+    m_command = instance->getPostExitCommand();
+    m_process.setProcessEnvironment(instance->createEnvironment());
+    connect(&m_process, &LoggedProcess::log, this, &PostLaunchCommand::logLines);
+    connect(&m_process, &LoggedProcess::stateChanged, this, &PostLaunchCommand::on_state);
+}
+
+void PostLaunchCommand::executeTask()
+{
+    QString postlaunch_cmd = m_parent->substituteVariables(m_command);
+    emit logLine(tr("Running Post-Launch command: %1").arg(postlaunch_cmd), MessageLevel::MultiMC);
+    m_process.start(postlaunch_cmd);
+}
+
+void PostLaunchCommand::on_state(LoggedProcess::State state)
+{
+    auto getError = [&]()
+    {
+        return tr("Post-Launch command failed with code %1.\n\n").arg(m_process.exitCode());
+    };
+    switch(state)
+    {
+        case LoggedProcess::Aborted:
+        case LoggedProcess::Crashed:
+        case LoggedProcess::FailedToStart:
+        {
+            auto error = getError();
+            emit logLine(error, MessageLevel::Fatal);
+            emitFailed(error);
+            return;
+        }
+        case LoggedProcess::Finished:
+        {
+            if(m_process.exitCode() != 0)
+            {
+                auto error = getError();
+                emit logLine(error, MessageLevel::Fatal);
+                emitFailed(error);
+            }
+            else
+            {
+                emit logLine(tr("Post-Launch command ran successfully.\n\n"), MessageLevel::MultiMC);
+                emitSucceeded();
+            }
+        }
+        default:
+            break;
+    }
+}
+
+void PostLaunchCommand::setWorkingDirectory(const QString &wd)
+{
+    m_process.setWorkingDirectory(wd);
+}
+
+bool PostLaunchCommand::abort()
+{
+    auto state = m_process.state();
+    if (state == LoggedProcess::Running || state == LoggedProcess::Starting)
+    {
+        m_process.kill();
+    }
+    return true;
+}
diff --git a/launcher/launch/steps/PostLaunchCommand.h b/launcher/launch/steps/PostLaunchCommand.h
new file mode 100644
index 00000000..ab4c494f
--- /dev/null
+++ b/launcher/launch/steps/PostLaunchCommand.h
@@ -0,0 +1,41 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <launch/LaunchStep.h>
+#include <LoggedProcess.h>
+
+class PostLaunchCommand: public LaunchStep
+{
+    Q_OBJECT
+public:
+    explicit PostLaunchCommand(LaunchTask *parent);
+    virtual ~PostLaunchCommand() {};
+
+    virtual void executeTask();
+    virtual bool abort();
+    virtual bool canAbort() const
+    {
+        return true;
+    }
+    void setWorkingDirectory(const QString &wd);
+private slots:
+    void on_state(LoggedProcess::State state);
+
+private:
+    LoggedProcess m_process;
+    QString m_command;
+};
diff --git a/launcher/launch/steps/PreLaunchCommand.cpp b/launcher/launch/steps/PreLaunchCommand.cpp
new file mode 100644
index 00000000..20e089e2
--- /dev/null
+++ b/launcher/launch/steps/PreLaunchCommand.cpp
@@ -0,0 +1,85 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "PreLaunchCommand.h"
+#include <launch/LaunchTask.h>
+
+PreLaunchCommand::PreLaunchCommand(LaunchTask *parent) : LaunchStep(parent)
+{
+    auto instance = m_parent->instance();
+    m_command = instance->getPreLaunchCommand();
+    m_process.setProcessEnvironment(instance->createEnvironment());
+    connect(&m_process, &LoggedProcess::log, this, &PreLaunchCommand::logLines);
+    connect(&m_process, &LoggedProcess::stateChanged, this, &PreLaunchCommand::on_state);
+}
+
+void PreLaunchCommand::executeTask()
+{
+    //FIXME: where to put this?
+    QString prelaunch_cmd = m_parent->substituteVariables(m_command);
+    emit logLine(tr("Running Pre-Launch command: %1").arg(prelaunch_cmd), MessageLevel::MultiMC);
+    m_process.start(prelaunch_cmd);
+}
+
+void PreLaunchCommand::on_state(LoggedProcess::State state)
+{
+    auto getError = [&]()
+    {
+        return tr("Pre-Launch command failed with code %1.\n\n").arg(m_process.exitCode());
+    };
+    switch(state)
+    {
+        case LoggedProcess::Aborted:
+        case LoggedProcess::Crashed:
+        case LoggedProcess::FailedToStart:
+        {
+            auto error = getError();
+            emit logLine(error, MessageLevel::Fatal);
+            emitFailed(error);
+            return;
+        }
+        case LoggedProcess::Finished:
+        {
+            if(m_process.exitCode() != 0)
+            {
+                auto error = getError();
+                emit logLine(error, MessageLevel::Fatal);
+                emitFailed(error);
+            }
+            else
+            {
+                emit logLine(tr("Pre-Launch command ran successfully.\n\n"), MessageLevel::MultiMC);
+                emitSucceeded();
+            }
+        }
+        default:
+            break;
+    }
+}
+
+void PreLaunchCommand::setWorkingDirectory(const QString &wd)
+{
+    m_process.setWorkingDirectory(wd);
+}
+
+bool PreLaunchCommand::abort()
+{
+    auto state = m_process.state();
+    if (state == LoggedProcess::Running || state == LoggedProcess::Starting)
+    {
+        m_process.kill();
+    }
+    return true;
+}
diff --git a/launcher/launch/steps/PreLaunchCommand.h b/launcher/launch/steps/PreLaunchCommand.h
new file mode 100644
index 00000000..dc069f71
--- /dev/null
+++ b/launcher/launch/steps/PreLaunchCommand.h
@@ -0,0 +1,41 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "launch/LaunchStep.h"
+#include "LoggedProcess.h"
+
+class PreLaunchCommand: public LaunchStep
+{
+    Q_OBJECT
+public:
+    explicit PreLaunchCommand(LaunchTask *parent);
+    virtual ~PreLaunchCommand() {};
+
+    virtual void executeTask();
+    virtual bool abort();
+    virtual bool canAbort() const
+    {
+        return true;
+    }
+    void setWorkingDirectory(const QString &wd);
+private slots:
+    void on_state(LoggedProcess::State state);
+
+private:
+    LoggedProcess m_process;
+    QString m_command;
+};
diff --git a/launcher/launch/steps/TextPrint.cpp b/launcher/launch/steps/TextPrint.cpp
new file mode 100644
index 00000000..0c1f320c
--- /dev/null
+++ b/launcher/launch/steps/TextPrint.cpp
@@ -0,0 +1,29 @@
+#include "TextPrint.h"
+
+TextPrint::TextPrint(LaunchTask * parent, const QStringList &lines, MessageLevel::Enum level) : LaunchStep(parent)
+{
+    m_lines = lines;
+    m_level = level;
+}
+TextPrint::TextPrint(LaunchTask *parent, const QString &line, MessageLevel::Enum level) : LaunchStep(parent)
+{
+    m_lines.append(line);
+    m_level = level;
+}
+
+void TextPrint::executeTask()
+{
+    emit logLines(m_lines, m_level);
+    emitSucceeded();
+}
+
+bool TextPrint::canAbort() const
+{
+    return true;
+}
+
+bool TextPrint::abort()
+{
+    emitFailed("Aborted.");
+    return true;
+}
diff --git a/launcher/launch/steps/TextPrint.h b/launcher/launch/steps/TextPrint.h
new file mode 100644
index 00000000..36fa7f9a
--- /dev/null
+++ b/launcher/launch/steps/TextPrint.h
@@ -0,0 +1,41 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <launch/LaunchStep.h>
+#include <LoggedProcess.h>
+#include <java/JavaChecker.h>
+
+/*
+ * FIXME: maybe do not export
+ */
+
+class TextPrint: public LaunchStep
+{
+    Q_OBJECT
+public:
+    explicit TextPrint(LaunchTask *parent, const QStringList &lines, MessageLevel::Enum level);
+    explicit TextPrint(LaunchTask *parent, const QString &line, MessageLevel::Enum level);
+    virtual ~TextPrint(){};
+
+    virtual void executeTask();
+    virtual bool canAbort() const;
+    virtual bool abort();
+
+private:
+    QStringList m_lines;
+    MessageLevel::Enum m_level;
+};
diff --git a/launcher/launch/steps/Update.cpp b/launcher/launch/steps/Update.cpp
new file mode 100644
index 00000000..28bd153d
--- /dev/null
+++ b/launcher/launch/steps/Update.cpp
@@ -0,0 +1,80 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "Update.h"
+#include <launch/LaunchTask.h>
+
+void Update::executeTask()
+{
+    if(m_aborted)
+    {
+        emitFailed(tr("Task aborted."));
+        return;
+    }
+    m_updateTask.reset(m_parent->instance()->createUpdateTask(m_mode));
+    if(m_updateTask)
+    {
+        connect(m_updateTask.get(), SIGNAL(finished()), this, SLOT(updateFinished()));
+        connect(m_updateTask.get(), &Task::progress, this, &Task::setProgress);
+        connect(m_updateTask.get(), &Task::status, this, &Task::setStatus);
+        emit progressReportingRequest();
+        return;
+    }
+    emitSucceeded();
+}
+
+void Update::proceed()
+{
+    m_updateTask->start();
+}
+
+void Update::updateFinished()
+{
+    if(m_updateTask->wasSuccessful())
+    {
+        m_updateTask.reset();
+        emitSucceeded();
+    }
+    else
+    {
+        QString reason = tr("Instance update failed because: %1\n\n").arg(m_updateTask->failReason());
+        m_updateTask.reset();
+        emit logLine(reason, MessageLevel::Fatal);
+        emitFailed(reason);
+    }
+}
+
+bool Update::canAbort() const
+{
+    if(m_updateTask)
+    {
+        return m_updateTask->canAbort();
+    }
+    return true;
+}
+
+
+bool Update::abort()
+{
+    m_aborted = true;
+    if(m_updateTask)
+    {
+        if(m_updateTask->canAbort())
+        {
+            return m_updateTask->abort();
+        }
+    }
+    return true;
+}
diff --git a/launcher/launch/steps/Update.h b/launcher/launch/steps/Update.h
new file mode 100644
index 00000000..0c9d91e0
--- /dev/null
+++ b/launcher/launch/steps/Update.h
@@ -0,0 +1,45 @@
+/* Copyright 2013-2021 MultiMC Contributors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include <launch/LaunchStep.h>
+#include <QObjectPtr.h>
+#include <LoggedProcess.h>
+#include <java/JavaChecker.h>
+#include <net/Mode.h>
+
+// FIXME: stupid. should be defined by the instance type? or even completely abstracted away...
+class Update: public LaunchStep
+{
+    Q_OBJECT
+public:
+    explicit Update(LaunchTask *parent, Net::Mode mode):LaunchStep(parent), m_mode(mode) {};
+    virtual ~Update() {};
+
+    void executeTask() override;
+    bool canAbort() const override;
+    void proceed() override;
+public slots:
+    bool abort() override;
+
+private slots:
+    void updateFinished();
+
+private:
+    shared_qobject_ptr<Task> m_updateTask;
+    bool m_aborted = false;
+    Net::Mode m_mode = Net::Mode::Offline;
+};