NOISSUE use model/view for Minecraft log data

api/logic/CMakeLists.txt

@@ -119,6 +119,8 @@ set(LAUNCH_SOURCES
 	launch/LaunchTask.h
 	launch/LoggedProcess.cpp
 	launch/LoggedProcess.h
+	launch/LogModel.cpp
+	launch/LogModel.h
 	launch/MessageLevel.cpp
 	launch/MessageLevel.h
 )

api/logic/launch/LaunchTask.cpp

@@ -167,6 +167,15 @@ bool LaunchTask::abort()
 	return false;
 }
 
+shared_qobject_ptr<LogModel> LaunchTask::getLogModel()
+{
+	if(!m_logModel)
+	{
+		m_logModel.reset(new LogModel());
+	}
+	return m_logModel;
+}
+
 void LaunchTask::onLogLines(const QStringList &lines, MessageLevel::Enum defaultLevel)
 {
 	for (auto & line: lines)
@@ -193,7 +202,8 @@ void LaunchTask::onLogLine(QString line, MessageLevel::Enum level)
 	// censor private user info
 	line = censorPrivateInfo(line);
 
-	emit log(line, level);
+	auto &model = *getLogModel();
+	model.append(level, line);
 }
 
 void LaunchTask::emitSucceeded()

api/logic/launch/LaunchTask.h

@@ -17,6 +17,8 @@
 
 #pragma once
 #include <QProcess>
+#include <QObjectPtr.h>
+#include "LogModel.h"
 #include "BaseInstance.h"
 #include "MessageLevel.h"
 #include "LoggedProcess.h"
@@ -80,6 +82,8 @@ public: /* methods */
 	 */
 	virtual bool abort() override;
 
+	shared_qobject_ptr<LogModel> getLogModel();
+
 public:
 	QString substituteVariables(const QString &cmd) const;
 	QString censorPrivateInfo(QString in);
@@ -98,13 +102,6 @@ signals:
 
 	void requestLogging();
 
-	/**
-	 * @brief emitted when we want to log something
-	 * @param text the text to log
-	 * @param level the level to log at
-	 */
-	void log(QString text, MessageLevel::Enum level = MessageLevel::MultiMC);
-
 public slots:
 	void onLogLines(const QStringList& lines, MessageLevel::Enum defaultLevel = MessageLevel::MultiMC);
 	void onLogLine(QString line, MessageLevel::Enum defaultLevel = MessageLevel::MultiMC);
@@ -114,6 +111,7 @@ public slots:
 
 protected: /* data */
 	InstancePtr m_instance;
+	shared_qobject_ptr<LogModel> m_logModel;
 	QList <std::shared_ptr<LaunchStep>> m_steps;
 	QMap<QString, QString> m_censorFilter;
 	int currentStep = -1;

api/logic/launch/LogModel.cpp

@@ -0,0 +1,135 @@
+#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)
+{
+	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::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 < 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;
+}
+
+void LogModel::setStopOnOverflow(bool stop)
+{
+	m_stopOnOverflow = stop;
+}
+
+void LogModel::setOverflowMessage(const QString& overflowMessage)
+{
+	m_overflowMessage = overflowMessage;
+}

api/logic/launch/LogModel.h

@@ -0,0 +1,51 @@
+#pragma once
+
+#include <QAbstractListModel>
+#include <QString>
+#include "MessageLevel.h"
+
+#include <multimc_logic_export.h>
+
+class MULTIMC_LOGIC_EXPORT 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();
+
+	QString toPlainText();
+
+	void setMaxLines(int maxLines);
+	void setStopOnOverflow(bool stop);
+	void setOverflowMessage(const QString & overflowMessage);
+
+	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";
+
+private:
+	Q_DISABLE_COPY(LogModel)
+};