From 3c4c830e202c70e714472ab6a705f63e450ce4a5 Mon Sep 17 00:00:00 2001
From: Megamouse <studienricky89@googlemail.com>
Date: Mon, 19 Apr 2021 20:14:08 +0200
Subject: [PATCH] Qt: Speed up Log Viewer

---
 rpcs3/rpcs3qt/log_viewer.cpp  | 17 +++++++----------
 rpcs3/rpcs3qt/log_viewer.h    | 12 ++++++------
 rpcs3/rpcs3qt/main_window.cpp |  1 +
 3 files changed, 14 insertions(+), 16 deletions(-)

diff --git a/rpcs3/rpcs3qt/log_viewer.cpp b/rpcs3/rpcs3qt/log_viewer.cpp
index f07a163a0d..fdb7a9ad26 100644
--- a/rpcs3/rpcs3qt/log_viewer.cpp
+++ b/rpcs3/rpcs3qt/log_viewer.cpp
@@ -5,6 +5,7 @@
 #include "syntax_highlighter.h"
 #include "find_dialog.h"
 
+#include <QApplication>
 #include <QMenu>
 #include <QFile>
 #include <QFileDialog>
@@ -35,7 +36,7 @@ log_viewer::log_viewer(std::shared_ptr<gui_settings> gui_settings)
 
 	m_path_last = m_gui_settings->GetValue(gui::fd_log_viewer).toString();
 
-	m_log_text = new QTextEdit(this);
+	m_log_text = new QPlainTextEdit(this);
 	m_log_text->setReadOnly(true);
 	m_log_text->setContextMenuPolicy(Qt::CustomContextMenu);
 	m_log_text->setWordWrapMode(QTextOption::NoWrap);
@@ -51,8 +52,6 @@ log_viewer::log_viewer(std::shared_ptr<gui_settings> gui_settings)
 	setLayout(layout);
 
 	connect(m_log_text, &QWidget::customContextMenuRequested, this, &log_viewer::show_context_menu);
-
-	show_log();
 }
 
 void log_viewer::show_context_menu(const QPoint& pos)
@@ -79,7 +78,7 @@ void log_viewer::show_context_menu(const QPoint& pos)
 		show_log();
 	});
 
-	const auto obj = qobject_cast<QTextEdit*>(sender());
+	const auto obj = qobject_cast<QPlainTextEdit*>(sender());
 
 	QPoint origin;
 
@@ -103,6 +102,8 @@ void log_viewer::show_log() const
 	}
 
 	m_log_text->clear();
+	m_log_text->setPlainText(tr("Loading file..."));
+	QApplication::processEvents();
 
 	if (QFile file(m_path_last);
 		file.exists() && file.open(QIODevice::ReadOnly | QIODevice::Text))
@@ -110,17 +111,13 @@ void log_viewer::show_log() const
 		m_gui_settings->SetValue(gui::fd_log_viewer, m_path_last);
 
 		QTextStream stream(&file);
-
-		while (!stream.atEnd())
-		{
-			m_log_text->append(stream.readLine());
-		}
-
+		m_log_text->setPlainText(stream.readAll());
 		file.close();
 	}
 	else
 	{
 		gui_log.error("log_viewer: Failed to open %s", sstr(m_path_last));
+		m_log_text->setPlainText(tr("Failed to open '%0'").arg(m_path_last));
 	}
 }
 
diff --git a/rpcs3/rpcs3qt/log_viewer.h b/rpcs3/rpcs3qt/log_viewer.h
index 9b18cf6fe3..16cf768191 100644
--- a/rpcs3/rpcs3qt/log_viewer.h
+++ b/rpcs3/rpcs3qt/log_viewer.h
@@ -1,6 +1,6 @@
 #pragma once
 
-#include <QTextEdit>
+#include <QPlainTextEdit>
 #include <QDropEvent>
 
 #include <memory>
@@ -13,22 +13,22 @@ class log_viewer : public QWidget
 {
 	Q_OBJECT
 
+public:
+	explicit log_viewer(std::shared_ptr<gui_settings> gui_settings);
+	void show_log() const;
+
 private Q_SLOTS:
 	void show_context_menu(const QPoint& pos);
 
 private:
-	void show_log() const;
 	bool is_valid_file(const QMimeData& md, bool save = false);
 
 	std::shared_ptr<gui_settings> m_gui_settings;
 	QString m_path_last;
-	QTextEdit* m_log_text;
+	QPlainTextEdit* m_log_text;
 	LogHighlighter* m_log_highlighter;
 	std::unique_ptr<find_dialog> m_find_dialog;
 
-public:
-	explicit log_viewer(std::shared_ptr<gui_settings> settings);
-
 protected:
 	void dropEvent(QDropEvent* ev) override;
 	void dragEnterEvent(QDragEnterEvent* ev) override;
diff --git a/rpcs3/rpcs3qt/main_window.cpp b/rpcs3/rpcs3qt/main_window.cpp
index 1cfca1dd59..1962aa4ec3 100644
--- a/rpcs3/rpcs3qt/main_window.cpp
+++ b/rpcs3/rpcs3qt/main_window.cpp
@@ -2113,6 +2113,7 @@ void main_window::CreateConnects()
 	{
 		log_viewer* viewer = new log_viewer(m_gui_settings);
 		viewer->show();
+		viewer->show_log();
 	});
 
 	connect(ui->toolskernel_explorerAct, &QAction::triggered, this, [this]