From e953f3a0c727e8026a3898a3241c2806576b2a93 Mon Sep 17 00:00:00 2001
From: Magnus Norddahl <dpjudas@users.noreply.github.com>
Date: Wed, 3 Jan 2024 03:10:26 +0100
Subject: [PATCH] Add scrollbar to the log

---
 src/common/widgets/errorwindow.cpp | 79 +++++++++++++++++++++++++++++-
 src/common/widgets/errorwindow.h   | 10 ++++
 2 files changed, 87 insertions(+), 2 deletions(-)

diff --git a/src/common/widgets/errorwindow.cpp b/src/common/widgets/errorwindow.cpp
index e8b28b9dee..11057a1f61 100644
--- a/src/common/widgets/errorwindow.cpp
+++ b/src/common/widgets/errorwindow.cpp
@@ -5,6 +5,7 @@
 #include "printf.h"
 #include <zwidget/core/image.h>
 #include <zwidget/widgets/pushbutton/pushbutton.h>
+#include <zwidget/widgets/scrollbar/scrollbar.h>
 
 bool ErrorWindow::ExecModal(const std::string& text, const std::string& log)
 {
@@ -105,7 +106,10 @@ void ErrorWindow::OnGeometryChanged()
 
 LogViewer::LogViewer(Widget* parent) : Widget(parent)
 {
-	SetNoncontentSizes(8.0, 8.0, 8.0, 8.0);
+	SetNoncontentSizes(8.0, 8.0, 3.0, 8.0);
+
+	scrollbar = new Scrollbar(this);
+	scrollbar->FuncScroll = [=]() { OnScrollbarScroll(); };
 }
 
 void LogViewer::SetText(const std::string& text, const std::string& log)
@@ -135,6 +139,9 @@ void LogViewer::SetText(const std::string& text, const std::string& log)
 	layout.AddText(text, largefont, Colorf::fromRgba8(255, 255, 170));
 	lines.push_back(layout);
 
+	scrollbar->SetRanges(0.0, (double)lines.size(), 1.0, 100.0);
+	scrollbar->SetPosition((double)lines.size() - 1.0);
+
 	Update();
 }
 
@@ -194,7 +201,8 @@ void LogViewer::OnPaint(Canvas* canvas)
 {
 	double width = GetWidth();
 	double y = GetHeight();
-	for (size_t i = lines.size(); i > 0 && y > 0.0; i--)
+	size_t start = std::min((size_t)std::round(scrollbar->GetPosition() + 1.0), lines.size());
+	for (size_t i = start; i > 0 && y > 0.0; i--)
 	{
 		SpanLayout& layout = lines[i - 1];
 		layout.Layout(canvas, width);
@@ -203,3 +211,70 @@ void LogViewer::OnPaint(Canvas* canvas)
 		y -= layout.GetSize().height;
 	}
 }
+
+void LogViewer::OnMouseWheel(const Point& pos, EInputKey key)
+{
+	if (key == IK_MouseWheelUp)
+	{
+		ScrollUp(4);
+	}
+	else if (key == IK_MouseWheelDown)
+	{
+		ScrollDown(4);
+	}
+}
+
+void LogViewer::OnKeyDown(EInputKey key)
+{
+	if (key == IK_Home)
+	{
+		scrollbar->SetPosition(0.0f);
+		Update();
+	}
+	if (key == IK_End)
+	{
+		scrollbar->SetPosition(scrollbar->GetMax());
+		Update();
+	}
+	else if (key == IK_PageUp)
+	{
+		ScrollUp(20);
+	}
+	else if (key == IK_PageDown)
+	{
+		ScrollDown(20);
+	}
+	else if (key == IK_Up)
+	{
+		ScrollUp(4);
+	}
+	else if (key == IK_Down)
+	{
+		ScrollDown(4);
+	}
+}
+
+void LogViewer::OnScrollbarScroll()
+{
+	Update();
+}
+
+void LogViewer::OnGeometryChanged()
+{
+	double w = GetWidth();
+	double h = GetHeight();
+	double sw = scrollbar->GetPreferredWidth();
+	scrollbar->SetFrameGeometry(Rect::xywh(w - sw, 0.0, sw, h));
+}
+
+void LogViewer::ScrollUp(int lines)
+{
+	scrollbar->SetPosition(std::max(scrollbar->GetPosition() - (double)lines, 0.0));
+	Update();
+}
+
+void LogViewer::ScrollDown(int lines)
+{
+	scrollbar->SetPosition(std::min(scrollbar->GetPosition() + (double)lines, scrollbar->GetMax()));
+	Update();
+}
diff --git a/src/common/widgets/errorwindow.h b/src/common/widgets/errorwindow.h
index 5f2ecf069f..63304b33f1 100644
--- a/src/common/widgets/errorwindow.h
+++ b/src/common/widgets/errorwindow.h
@@ -5,6 +5,7 @@
 
 class LogViewer;
 class PushButton;
+class Scrollbar;
 
 class ErrorWindow : public Widget
 {
@@ -42,10 +43,19 @@ public:
 protected:
 	void OnPaintFrame(Canvas* canvas) override;
 	void OnPaint(Canvas* canvas) override;
+	void OnMouseWheel(const Point& pos, EInputKey key) override;
+	void OnKeyDown(EInputKey key) override;
+	void OnGeometryChanged() override;
 
 private:
+	void OnScrollbarScroll();
+	void ScrollUp(int lines);
+	void ScrollDown(int lines);
+
 	SpanLayout CreateLineLayout(const std::string& text);
 
+	Scrollbar* scrollbar = nullptr;
+
 	std::shared_ptr<Font> largefont = Font::Create("Poppins", 16.0);
 	std::shared_ptr<Font> font = Font::Create("Poppins", 12.0);
 	std::vector<SpanLayout> lines;