From d73a6674372d12f605b31c2aa2fb9406d049c054 Mon Sep 17 00:00:00 2001
From: Bananymous <oskari.alaranta@bananymous.com>
Date: Fri, 27 Jun 2025 13:49:15 +0300
Subject: [PATCH] LibGUI: Implement very bad widget system :D

---
 userspace/libraries/LibGUI/CMakeLists.txt     |   6 +
 userspace/libraries/LibGUI/Widget/Button.cpp  |  60 +++++
 userspace/libraries/LibGUI/Widget/Grid.cpp    |  53 ++++
 userspace/libraries/LibGUI/Widget/Label.cpp   |  44 ++++
 .../libraries/LibGUI/Widget/RoundedWidget.cpp | 117 +++++++++
 .../libraries/LibGUI/Widget/TextArea.cpp      |  96 +++++++
 userspace/libraries/LibGUI/Widget/Widget.cpp  | 241 ++++++++++++++++++
 userspace/libraries/LibGUI/Window.cpp         |  61 ++++-
 .../LibGUI/include/LibGUI/Widget/Button.h     |  54 ++++
 .../LibGUI/include/LibGUI/Widget/Grid.h       |  42 +++
 .../LibGUI/include/LibGUI/Widget/Label.h      |  44 ++++
 .../include/LibGUI/Widget/RoundedWidget.h     |  42 +++
 .../LibGUI/include/LibGUI/Widget/TextArea.h   |  50 ++++
 .../LibGUI/include/LibGUI/Widget/Widget.h     | 163 ++++++++++++
 .../libraries/LibGUI/include/LibGUI/Window.h  |   5 +
 15 files changed, 1076 insertions(+), 2 deletions(-)
 create mode 100644 userspace/libraries/LibGUI/Widget/Button.cpp
 create mode 100644 userspace/libraries/LibGUI/Widget/Grid.cpp
 create mode 100644 userspace/libraries/LibGUI/Widget/Label.cpp
 create mode 100644 userspace/libraries/LibGUI/Widget/RoundedWidget.cpp
 create mode 100644 userspace/libraries/LibGUI/Widget/TextArea.cpp
 create mode 100644 userspace/libraries/LibGUI/Widget/Widget.cpp
 create mode 100644 userspace/libraries/LibGUI/include/LibGUI/Widget/Button.h
 create mode 100644 userspace/libraries/LibGUI/include/LibGUI/Widget/Grid.h
 create mode 100644 userspace/libraries/LibGUI/include/LibGUI/Widget/Label.h
 create mode 100644 userspace/libraries/LibGUI/include/LibGUI/Widget/RoundedWidget.h
 create mode 100644 userspace/libraries/LibGUI/include/LibGUI/Widget/TextArea.h
 create mode 100644 userspace/libraries/LibGUI/include/LibGUI/Widget/Widget.h

diff --git a/userspace/libraries/LibGUI/CMakeLists.txt b/userspace/libraries/LibGUI/CMakeLists.txt
index 361b17f3..7f81b5fc 100644
--- a/userspace/libraries/LibGUI/CMakeLists.txt
+++ b/userspace/libraries/LibGUI/CMakeLists.txt
@@ -1,5 +1,11 @@
 set(LIBGUI_SOURCES
 	Texture.cpp
+	Widget/Button.cpp
+	Widget/Grid.cpp
+	Widget/Label.cpp
+	Widget/RoundedWidget.cpp
+	Widget/TextArea.cpp
+	Widget/Widget.cpp
 	Window.cpp
 )
 
diff --git a/userspace/libraries/LibGUI/Widget/Button.cpp b/userspace/libraries/LibGUI/Widget/Button.cpp
new file mode 100644
index 00000000..eeebc96c
--- /dev/null
+++ b/userspace/libraries/LibGUI/Widget/Button.cpp
@@ -0,0 +1,60 @@
+#include <LibFont/Font.h>
+#include <LibGUI/Widget/Button.h>
+#include <LibGUI/Window.h>
+
+namespace LibGUI::Widget
+{
+
+	BAN::ErrorOr<BAN::RefPtr<Button>> Button::create(BAN::RefPtr<Widget> parent, BAN::StringView text, Rectangle geometry)
+	{
+		auto* button_ptr = new Button(parent, geometry);
+		if (button_ptr == nullptr)
+			return BAN::Error::from_errno(ENOMEM);
+		auto button = BAN::RefPtr<Button>::adopt(button_ptr);
+		TRY(button->initialize(color_invisible));
+		TRY(button->m_text.append(text));
+		return button;
+	}
+
+	BAN::ErrorOr<void> Button::set_text(BAN::StringView text)
+	{
+		m_text.clear();
+		TRY(m_text.append(text));
+		if (is_shown())
+			show();
+		return {};
+	}
+
+	void Button::update_impl()
+	{
+		const bool hover_color = is_hovered() && !is_child_hovered();
+		if (hover_color != m_hover_state)
+			show();
+	}
+
+	void Button::show_impl()
+	{
+		m_hover_state = is_hovered() && !is_child_hovered();
+
+		const auto& font = default_font();
+		const int32_t text_h = font.height();
+		const int32_t text_w = font.width() * m_text.size();
+
+		const int32_t off_x = (static_cast<int32_t>(width())  - text_w) / 2;
+		const int32_t off_y = (static_cast<int32_t>(height()) - text_h) / 2;
+
+		m_texture.fill(m_hover_state ? m_style.color_hovered : m_style.color_normal);
+		m_texture.draw_text(m_text, font, off_x, off_y, m_style.color_text);
+
+		RoundedWidget::style() = m_style;
+		RoundedWidget::show_impl();
+	}
+
+	bool Button::on_mouse_button_impl(LibGUI::EventPacket::MouseButtonEvent::event_t event)
+	{
+		if (event.pressed && event.button == LibInput::MouseButton::Left && m_click_callback)
+			m_click_callback();
+		return true;
+	}
+
+}
diff --git a/userspace/libraries/LibGUI/Widget/Grid.cpp b/userspace/libraries/LibGUI/Widget/Grid.cpp
new file mode 100644
index 00000000..61fc4b54
--- /dev/null
+++ b/userspace/libraries/LibGUI/Widget/Grid.cpp
@@ -0,0 +1,53 @@
+#include <LibGUI/Widget/Grid.h>
+
+namespace LibGUI::Widget
+{
+
+	BAN::ErrorOr<BAN::RefPtr<Grid>> Grid::create(BAN::RefPtr<Widget> parent, uint32_t cols, uint32_t rows, uint32_t color, Rectangle geometry)
+	{
+		auto* grid_ptr = new Grid(parent, geometry, cols, rows);
+		if (grid_ptr == nullptr)
+			return BAN::Error::from_errno(ENOMEM);
+		auto grid = BAN::RefPtr<Grid>::adopt(grid_ptr);
+		TRY(grid->initialize(color));
+		return grid;
+	}
+
+	Widget::Rectangle Grid::grid_element_area(const GridElement& element) const
+	{
+		const uint32_t this_x = element.col * width()  / m_cols;
+		const uint32_t this_y = element.row * height() / m_rows;
+
+		const uint32_t next_x = (element.col + element.col_span) * width() / m_cols;
+		const uint32_t next_y = (element.row + element.row_span) * height() / m_rows;
+
+		return Widget::Rectangle {
+			.x = static_cast<int32_t>(this_x),
+			.y = static_cast<int32_t>(this_y),
+			.w = next_x - this_x,
+			.h = next_y - this_y,
+		};
+	}
+
+	BAN::ErrorOr<void> Grid::update_geometry_impl()
+	{
+		for (auto& grid_element : m_grid_elements)
+			TRY(grid_element.widget->set_fixed_geometry(grid_element_area(grid_element)));
+		return {};
+	}
+
+	BAN::ErrorOr<void> Grid::set_widget_position(BAN::RefPtr<Widget> widget, uint32_t col, uint32_t col_span, uint32_t row, uint32_t row_span)
+	{
+		if (col_span == 0 || row_span == 0)
+			return BAN::Error::from_errno(EINVAL);
+		if (col + col_span > m_cols)
+			return BAN::Error::from_errno(EINVAL);
+		if (row + row_span > m_rows)
+			return BAN::Error::from_errno(EINVAL);
+		ASSERT(widget->parent() == this);
+		TRY(m_grid_elements.emplace_back(widget, col, col_span, row, row_span));
+		TRY(widget->set_fixed_geometry(grid_element_area(m_grid_elements.back())));
+		return {};
+	}
+
+}
diff --git a/userspace/libraries/LibGUI/Widget/Label.cpp b/userspace/libraries/LibGUI/Widget/Label.cpp
new file mode 100644
index 00000000..0f323169
--- /dev/null
+++ b/userspace/libraries/LibGUI/Widget/Label.cpp
@@ -0,0 +1,44 @@
+#include <LibFont/Font.h>
+#include <LibGUI/Widget/Label.h>
+#include <LibGUI/Window.h>
+
+namespace LibGUI::Widget
+{
+
+	BAN::ErrorOr<BAN::RefPtr<Label>> Label::create(BAN::RefPtr<Widget> parent, BAN::StringView text, Rectangle geometry)
+	{
+		auto* label_ptr = new Label(parent, geometry);
+		if (label_ptr == nullptr)
+			return BAN::Error::from_errno(ENOMEM);
+		auto label = BAN::RefPtr<Label>::adopt(label_ptr);
+		TRY(label->initialize(color_invisible));
+		TRY(label->m_text.append(text));
+		return label;
+	}
+
+	BAN::ErrorOr<void> Label::set_text(BAN::StringView text)
+	{
+		m_text.clear();
+		TRY(m_text.append(text));
+		if (is_shown())
+			show();
+		return {};
+	}
+
+	void Label::show_impl()
+	{
+		const auto& font = default_font();
+		const int32_t text_h = font.height();
+		const int32_t text_w = font.width() * m_text.size();
+
+		const int32_t off_x = (static_cast<int32_t>(width())  - text_w) / 2;
+		const int32_t off_y = (static_cast<int32_t>(height()) - text_h) / 2;
+
+		m_texture.fill(m_style.color_normal);
+		m_texture.draw_text(m_text, font, off_x, off_y, m_style.color_text);
+
+		RoundedWidget::style() = m_style;
+		RoundedWidget::show_impl();
+	}
+
+}
diff --git a/userspace/libraries/LibGUI/Widget/RoundedWidget.cpp b/userspace/libraries/LibGUI/Widget/RoundedWidget.cpp
new file mode 100644
index 00000000..743882c5
--- /dev/null
+++ b/userspace/libraries/LibGUI/Widget/RoundedWidget.cpp
@@ -0,0 +1,117 @@
+#include <LibGUI/Widget/RoundedWidget.h>
+
+namespace LibGUI::Widget
+{
+
+	bool RoundedWidget::contains(Point point) const
+	{
+		if (!Widget::contains(point))
+			return false;
+
+		const auto is_outside_corner =
+			[this]<uint8_t quadrant>(Point point) -> bool
+			{
+				const auto radius = m_style.corner_radius;
+				const uint32_t base_x = (quadrant % 2) ? m_texture.width()  - radius - 1 : 0;
+				const uint32_t base_y = (quadrant / 2) ? m_texture.height() - radius - 1 : 0;
+
+				if (point.x < static_cast<int32_t>(base_x) || point.x > static_cast<int32_t>(base_x + radius))
+					return false;
+				if (point.y < static_cast<int32_t>(base_y) || point.y > static_cast<int32_t>(base_y + radius))
+					return false;
+
+				const uint32_t x_off = point.x - base_x;
+				const uint32_t y_off = point.y - base_y;
+
+				const uint32_t dx = ((quadrant % 2) ? x_off : radius - x_off);
+				const uint32_t dy = ((quadrant / 2) ? y_off : radius - y_off);
+				const uint32_t distance = dx * dx + dy * dy;
+
+				return distance >= radius * radius;
+			};
+
+		if (is_outside_corner.operator()<0>(point))
+			return false;
+		if (is_outside_corner.operator()<1>(point))
+			return false;
+		if (is_outside_corner.operator()<2>(point))
+			return false;
+		if (is_outside_corner.operator()<3>(point))
+			return false;
+		return true;
+	}
+
+	void RoundedWidget::show_impl()
+	{
+		if (m_style.border_width)
+		{
+			m_texture.fill_rect(
+				0,
+				0,
+				m_texture.width(),
+				m_style.border_width,
+				m_style.color_border
+			);
+			m_texture.fill_rect(
+				0,
+				0,
+				m_style.border_width,
+				m_texture.height(),
+				m_style.color_border
+			);
+			m_texture.fill_rect(
+				0,
+				m_texture.height() - m_style.border_width,
+				m_texture.width(),
+				m_style.border_width,
+				m_style.color_border
+			);
+			m_texture.fill_rect(
+				m_texture.width() - m_style.border_width,
+				0,
+				m_style.border_width,
+				m_texture.height(),
+				m_style.color_border
+			);
+		}
+
+		if (m_style.corner_radius)
+		{
+			const auto draw_corner =
+				[this]<uint8_t quadrant>()
+				{
+					const auto radius = m_style.corner_radius;
+					const uint32_t base_x = (quadrant % 2) ? m_texture.width()  - radius - 1 : 0;
+					const uint32_t base_y = (quadrant / 2) ? m_texture.height() - radius - 1 : 0;
+					const uint32_t distance_max = radius * radius;
+					const uint32_t distance_min = (radius - m_style.border_width) * (radius - m_style.border_width);
+
+					for (uint32_t y_off = 0; y_off <= radius; y_off++)
+					{
+						for (uint32_t x_off = 0; x_off <= radius; x_off++)
+						{
+							const uint32_t dx = ((quadrant % 2) ? x_off : radius - x_off);
+							const uint32_t dy = ((quadrant / 2) ? y_off : radius - y_off);
+							const uint32_t distance = dx * dx + dy * dy;
+
+							if (base_x + x_off >= m_texture.width())
+								continue;
+							if (base_y + y_off >= m_texture.height())
+								continue;
+
+							if (distance > distance_max)
+								m_texture.set_pixel(base_x + x_off, base_y + y_off, color_invisible);
+							else if (distance >= distance_min)
+								m_texture.set_pixel(base_x + x_off, base_y + y_off, m_style.color_border);
+						}
+					}
+				};
+
+			draw_corner.operator()<0>();
+			draw_corner.operator()<1>();
+			draw_corner.operator()<2>();
+			draw_corner.operator()<3>();
+		}
+	}
+
+}
diff --git a/userspace/libraries/LibGUI/Widget/TextArea.cpp b/userspace/libraries/LibGUI/Widget/TextArea.cpp
new file mode 100644
index 00000000..0a1afa91
--- /dev/null
+++ b/userspace/libraries/LibGUI/Widget/TextArea.cpp
@@ -0,0 +1,96 @@
+#include <LibFont/Font.h>
+#include <LibGUI/Widget/TextArea.h>
+#include <LibGUI/Window.h>
+
+#include <ctype.h>
+
+namespace LibGUI::Widget
+{
+
+	BAN::ErrorOr<BAN::RefPtr<TextArea>> TextArea::create(BAN::RefPtr<Widget> parent, BAN::StringView text, Rectangle geometry)
+	{
+		auto* text_area_ptr = new TextArea(parent, geometry);
+		if (text_area_ptr == nullptr)
+			return BAN::Error::from_errno(ENOMEM);
+		auto text_area = BAN::RefPtr<TextArea>::adopt(text_area_ptr);
+		TRY(text_area->initialize(color_invisible));
+		TRY(text_area->set_text(text));
+		return text_area;
+	}
+
+	BAN::ErrorOr<void> TextArea::set_text(BAN::StringView text)
+	{
+		m_text.clear();
+		TRY(m_text.append(text));
+		TRY(wrap_text());
+		if (is_shown())
+			show();
+		return {};
+	}
+
+	uint32_t TextArea::get_required_height() const
+	{
+		auto& font = default_font();
+		return m_wrapped_text.size() * font.height();
+	}
+
+	BAN::ErrorOr<void> TextArea::wrap_text()
+	{
+		m_wrapped_text.clear();
+
+		if (width() == 0)
+			return {};
+
+		auto& font = default_font();
+
+		const uint32_t total_columns = width() / font.width();
+		ASSERT(total_columns != 0);
+
+		TRY(m_wrapped_text.emplace_back());
+
+		for (size_t i = 0; i < m_text.size(); i++)
+		{
+			if (m_text[i] == '\n')
+				TRY(m_wrapped_text.emplace_back());
+			else if (isspace(m_text[i]) && m_wrapped_text.back().size() == 0)
+				;
+			else
+			{
+				TRY(m_wrapped_text.back().push_back(m_text[i]));
+
+				if (i + 1 < m_text.size() && isspace(m_text[i]) && !isspace(m_text[i + 1]))
+				{
+					size_t word_len = 0;
+					for (size_t j = i + 1; j < m_text.size() && !isspace(m_text[j]); j++)
+						word_len++;
+					if (word_len <= total_columns && m_wrapped_text.back().size() + word_len > total_columns)
+						TRY(m_wrapped_text.emplace_back());
+				}
+
+				if (m_wrapped_text.back().size() >= total_columns)
+					TRY(m_wrapped_text.emplace_back());
+			}
+		}
+
+		return {};
+	}
+
+	BAN::ErrorOr<void> TextArea::update_geometry_impl()
+	{
+		TRY(wrap_text());
+		return Widget::update_geometry_impl();
+	}
+
+	void TextArea::show_impl()
+	{
+		const auto& font = default_font();
+
+		m_texture.fill(m_style.color_normal);
+		for (int32_t row = 0; row < static_cast<int32_t>(m_wrapped_text.size()); row++)
+			m_texture.draw_text(m_wrapped_text[row].sv(), font, 0, row * font.height(), m_style.color_text);
+
+		RoundedWidget::style() = m_style;
+		RoundedWidget::show_impl();
+	}
+
+}
diff --git a/userspace/libraries/LibGUI/Widget/Widget.cpp b/userspace/libraries/LibGUI/Widget/Widget.cpp
new file mode 100644
index 00000000..d6489d87
--- /dev/null
+++ b/userspace/libraries/LibGUI/Widget/Widget.cpp
@@ -0,0 +1,241 @@
+#include <LibGUI/Widget/Widget.h>
+#include <LibFont/Font.h>
+
+namespace LibGUI::Widget
+{
+
+	static BAN::Optional<LibFont::Font> s_default_font;
+
+	BAN::ErrorOr<void> Widget::set_default_font(BAN::StringView path)
+	{
+		s_default_font = TRY(LibFont::Font::load(path));
+		return {};
+	}
+
+	const LibFont::Font& Widget::default_font()
+	{
+		if (!s_default_font.has_value())
+			MUST(set_default_font("/usr/share/fonts/lat0-16.psfu"_sv));
+		return s_default_font.value();
+	}
+
+	BAN::ErrorOr<BAN::RefPtr<Widget>> Widget::create(BAN::RefPtr<Widget> parent, uint32_t color, Rectangle area)
+	{
+		auto* widget_ptr = new Widget(parent, area);
+		if (widget_ptr == nullptr)
+			return BAN::Error::from_errno(ENOMEM);
+		auto widget = BAN::RefPtr<Widget>::adopt(widget_ptr);
+		TRY(widget->initialize(color));
+		return widget;
+	}
+
+	BAN::ErrorOr<void> Widget::initialize(uint32_t color)
+	{
+		m_texture = TRY(Texture::create(width(), height(), color));
+		if (m_parent)
+			TRY(m_parent->m_children.push_back(this));
+		return {};
+	}
+
+	bool Widget::is_child_hovered() const
+	{
+		for (auto child : m_children)
+			if (child->m_hovered || child->is_child_hovered())
+				return true;
+		return false;
+	}
+
+	BAN::ErrorOr<void> Widget::set_fixed_geometry(Rectangle area)
+	{
+		TRY(m_texture.resize(area.w, area.h));
+		m_fixed_area = area;
+		m_relative_area.clear();
+
+		TRY(update_geometry_impl());
+
+		if (is_shown())
+			show();
+
+		return {};
+	}
+
+	BAN::ErrorOr<void> Widget::set_relative_geometry(FloatRectangle area)
+	{
+		if (area.w < 0.0f || area.h < 0.0f)
+			return BAN::Error::from_errno(EINVAL);
+		ASSERT(m_parent);
+
+		TRY(set_fixed_geometry({
+			.x = static_cast<int32_t>(area.x * m_parent->width()),
+			.y = static_cast<int32_t>(area.y * m_parent->height()),
+			.w = static_cast<uint32_t>(area.w * m_parent->width()),
+			.h = static_cast<uint32_t>(area.h * m_parent->height()),
+		}));
+
+		m_relative_area = area;
+		return {};
+	}
+
+	BAN::ErrorOr<void> Widget::update_geometry_impl()
+	{
+		for (auto child : m_children)
+		{
+			if (!child->m_relative_area.has_value())
+				continue;
+			TRY(child->set_relative_geometry(child->m_relative_area.value()));
+		}
+		return {};
+	}
+
+	void Widget::show()
+	{
+		m_shown = true;
+
+		show_impl();
+		m_changed = true;
+
+		for (auto child : m_children)
+			if (child->is_shown())
+				child->show();
+	}
+
+	void Widget::hide()
+	{
+		if (!is_shown())
+			return;
+		m_shown = false;
+
+		auto root = m_parent;
+		while (root && root->m_parent)
+			root = root->m_parent;
+		if (root)
+			root->show();
+	}
+
+	void Widget::before_mouse_move()
+	{
+		if (!is_shown())
+			return;
+
+		m_old_hovered = m_hovered;
+		m_hovered = false;
+
+		for (auto child : m_children)
+			child->before_mouse_move();
+	}
+
+	void Widget::after_mouse_move()
+	{
+		if (!is_shown())
+			return;
+
+		if (m_old_hovered != m_hovered)
+			on_hover_change_impl(m_hovered);
+
+		for (auto child : m_children)
+			child->after_mouse_move();
+	}
+
+	bool Widget::on_mouse_move(LibGUI::EventPacket::MouseMoveEvent::event_t event)
+	{
+		if (!Rectangle { 0, 0, width(), height() }.contains({ event.x, event.y }))
+			return false;
+		if (!is_shown())
+			return false;
+
+		m_hovered = contains({ event.x, event.y });
+
+		for (auto child : m_children)
+		{
+			auto rel_event = event;
+			rel_event.x -= child->m_fixed_area.x;
+			rel_event.y -= child->m_fixed_area.y;
+			if (child->on_mouse_move(rel_event))
+				return true;
+		}
+
+		if (!m_hovered)
+			return false;
+		return on_mouse_move_impl(event);
+	}
+
+	bool Widget::on_mouse_button(LibGUI::EventPacket::MouseButtonEvent::event_t event)
+	{
+		if (!Rectangle { 0, 0, width(), height() }.contains({ event.x, event.y }))
+			return false;
+		if (!is_shown())
+			return false;
+
+		for (auto child : m_children)
+		{
+			auto rel_event = event;
+			rel_event.x -= child->m_fixed_area.x;
+			rel_event.y -= child->m_fixed_area.y;
+			if (child->on_mouse_button(rel_event))
+				return true;
+		}
+
+		if (!contains({ event.x, event.y }))
+			return false;
+		return on_mouse_button_impl(event);
+	}
+
+	Widget::Rectangle Widget::render(Texture& output, Point parent_position, Rectangle out_area)
+	{
+		if (!is_shown())
+			return {};
+
+		update_impl();
+
+		Rectangle invalidated {};
+		if (m_changed)
+		{
+			auto where_i_would_be = Rectangle {
+				.x = parent_position.x + m_fixed_area.x,
+				.y = parent_position.y + m_fixed_area.y,
+				.w = m_fixed_area.w,
+				.h = m_fixed_area.h,
+			};
+
+			auto where_to_draw = out_area.overlap(where_i_would_be);
+
+			if (where_to_draw.w && where_to_draw.h)
+			{
+				output.copy_texture(
+					m_texture,
+					where_to_draw.x,
+					where_to_draw.y,
+					where_to_draw.x - where_i_would_be.x,
+					where_to_draw.y - where_i_would_be.y,
+					where_to_draw.w,
+					where_to_draw.h
+				);
+			}
+
+			invalidated = where_to_draw;
+			m_changed = false;
+		}
+
+		out_area = out_area.overlap({
+			.x = parent_position.x + m_fixed_area.x,
+			.y = parent_position.y + m_fixed_area.y,
+			.w = m_fixed_area.w,
+			.h = m_fixed_area.h,
+		});
+
+		parent_position = {
+			.x = parent_position.x + m_fixed_area.x,
+			.y = parent_position.y + m_fixed_area.y,
+		};
+
+		for (auto child : m_children)
+		{
+			invalidated = invalidated.bounding_box(
+				child->render(output, parent_position, out_area)
+			);
+		}
+
+		return invalidated;
+	}
+
+}
diff --git a/userspace/libraries/LibGUI/Window.cpp b/userspace/libraries/LibGUI/Window.cpp
index a5661961..9e2ab867 100644
--- a/userspace/libraries/LibGUI/Window.cpp
+++ b/userspace/libraries/LibGUI/Window.cpp
@@ -113,6 +113,17 @@ namespace LibGUI
 		return window;
 	}
 
+	BAN::ErrorOr<void> Window::set_root_widget(BAN::RefPtr<Widget::Widget> widget)
+	{
+		TRY(widget->set_fixed_geometry({ 0, 0, m_width, m_height }));
+		m_root_widget = widget;
+		m_root_widget->show();
+		const auto invalidated = m_root_widget->render(m_texture, { 0, 0 }, { 0, 0, m_width, m_height });
+		if (invalidated.w && invalidated.h)
+			invalidate(invalidated.x, invalidated.y, invalidated.w, invalidated.h);
+		return {};
+	}
+
 	void Window::invalidate(int32_t x, int32_t y, uint32_t width, uint32_t height)
 	{
 		if (!m_texture.clamp_to_texture(x, y, width, height))
@@ -168,6 +179,28 @@ namespace LibGUI
 			return on_socket_error(__FUNCTION__);
 	}
 
+	void Window::set_cursor_visible(bool visible)
+	{
+		auto attributes = m_attributes;
+		if (attributes.cursor_visible == visible)
+			return;
+		attributes.cursor_visible = visible;
+		set_attributes(attributes);
+	}
+
+	void Window::set_cursor(uint32_t width, uint32_t height, BAN::Span<uint32_t> pixels)
+	{
+		WindowPacket::WindowSetCursor packet;
+		packet.width = width;
+		packet.height = height;
+		MUST(packet.pixels.resize(pixels.size()));
+		for (size_t i = 0; i < packet.pixels.size(); i++)
+			packet.pixels[i] = pixels[i];
+
+		if (auto ret = packet.send_serialized(m_server_fd); ret.is_error())
+			return on_socket_error(__FUNCTION__);
+	}
+
 	void Window::set_min_size(uint32_t width, uint32_t height)
 	{
 		WindowPacket::WindowSetMinSize packet;
@@ -238,6 +271,9 @@ namespace LibGUI
 
 		TRY(m_texture.resize(event.width, event.height));
 
+		if (m_root_widget)
+			TRY(m_root_widget->set_fixed_geometry({ 0, 0, event.width, event.height }));
+
 		void* framebuffer_addr = smo_map(event.smo_key);
 		if (framebuffer_addr == nullptr)
 			return BAN::Error::from_errno(errno);
@@ -304,13 +340,27 @@ namespace LibGUI
 						m_key_event_callback(TRY_OR_BREAK(EventPacket::KeyEvent::deserialize(packet_data.span())).event);
 					break;
 				case PacketType::MouseButtonEvent:
+				{
+					auto event = TRY_OR_BREAK(EventPacket::MouseButtonEvent::deserialize(packet_data.span())).event;
 					if (m_mouse_button_event_callback)
-						m_mouse_button_event_callback(TRY_OR_BREAK(EventPacket::MouseButtonEvent::deserialize(packet_data.span())).event);
+						m_mouse_button_event_callback(event);
+					if (m_root_widget)
+						m_root_widget->on_mouse_button(event);
 					break;
+				}
 				case PacketType::MouseMoveEvent:
+				{
+					auto event = TRY_OR_BREAK(EventPacket::MouseMoveEvent::deserialize(packet_data.span())).event;
 					if (m_mouse_move_event_callback)
-						m_mouse_move_event_callback(TRY_OR_BREAK(EventPacket::MouseMoveEvent::deserialize(packet_data.span())).event);
+						m_mouse_move_event_callback(event);
+					if (m_root_widget)
+					{
+						m_root_widget->before_mouse_move();
+						m_root_widget->on_mouse_move(event);
+						m_root_widget->after_mouse_move();
+					}
 					break;
+				}
 				case PacketType::MouseScrollEvent:
 					if (m_mouse_scroll_event_callback)
 						m_mouse_scroll_event_callback(TRY_OR_BREAK(EventPacket::MouseScrollEvent::deserialize(packet_data.span())).event);
@@ -320,6 +370,13 @@ namespace LibGUI
 			}
 		}
 #undef TRY_OR_BREAK
+
+		if (m_root_widget)
+		{
+			const auto invalidated = m_root_widget->render(m_texture, { 0, 0 }, { 0, 0, m_width, m_height });
+			if (invalidated.w && invalidated.h)
+				invalidate(invalidated.x, invalidated.y, invalidated.w, invalidated.h);
+		}
 	}
 
 }
diff --git a/userspace/libraries/LibGUI/include/LibGUI/Widget/Button.h b/userspace/libraries/LibGUI/include/LibGUI/Widget/Button.h
new file mode 100644
index 00000000..6bb16bb2
--- /dev/null
+++ b/userspace/libraries/LibGUI/include/LibGUI/Widget/Button.h
@@ -0,0 +1,54 @@
+#pragma once
+
+#include <BAN/Function.h>
+#include <BAN/StringView.h>
+
+#include <LibGUI/Widget/RoundedWidget.h>
+
+namespace LibGUI::Widget
+{
+
+	class Button : public RoundedWidget
+	{
+	public:
+		struct Style : RoundedWidget::Style
+		{
+			Style()
+				: RoundedWidget::Style()
+				, color_hovered(0x808080)
+				, color_text(0x000000)
+			{}
+
+			uint32_t color_hovered;
+			uint32_t color_text;
+		};
+
+	public:
+		static BAN::ErrorOr<BAN::RefPtr<Button>> create(BAN::RefPtr<Widget> parent, BAN::StringView text, Rectangle geometry = {});
+
+		BAN::ErrorOr<void> set_text(BAN::StringView);
+
+		Style& style() { return m_style; }
+		const Style& style() const { return m_style; }
+
+		void set_click_callback(BAN::Function<void()> callback) { m_click_callback = callback; }
+
+	protected:
+		Button(BAN::RefPtr<Widget> parent, Rectangle area)
+			: RoundedWidget(parent, area)
+		{ }
+
+		void update_impl() override;
+		void show_impl() override;
+
+		bool on_mouse_button_impl(LibGUI::EventPacket::MouseButtonEvent::event_t) override;
+
+	private:
+		Style m_style;
+		bool m_hover_state { false };
+		BAN::String m_text;
+
+		BAN::Function<void()> m_click_callback;
+	};
+
+}
diff --git a/userspace/libraries/LibGUI/include/LibGUI/Widget/Grid.h b/userspace/libraries/LibGUI/include/LibGUI/Widget/Grid.h
new file mode 100644
index 00000000..6bf7eeef
--- /dev/null
+++ b/userspace/libraries/LibGUI/include/LibGUI/Widget/Grid.h
@@ -0,0 +1,42 @@
+#pragma once
+
+#include <LibGUI/Widget/Widget.h>
+
+namespace LibGUI::Widget
+{
+
+	class Grid : public Widget
+	{
+	public:
+		static BAN::ErrorOr<BAN::RefPtr<Grid>> create(BAN::RefPtr<Widget> parent, uint32_t cols, uint32_t rows, uint32_t color = color_invisible, Rectangle geometry = {});
+
+		BAN::ErrorOr<void> set_widget_position(BAN::RefPtr<Widget> widget, uint32_t col, uint32_t col_span, uint32_t row, uint32_t row_span);
+
+	protected:
+		Grid(BAN::RefPtr<Widget> parent, Rectangle geometry, uint32_t cols, uint32_t rows)
+			: Widget(parent, geometry)
+			, m_cols(cols)
+			, m_rows(rows)
+		{ }
+
+		BAN::ErrorOr<void> update_geometry_impl() override;
+
+	private:
+		struct GridElement
+		{
+			BAN::RefPtr<Widget> widget;
+			uint32_t col;
+			uint32_t col_span;
+			uint32_t row;
+			uint32_t row_span;
+		};
+
+		Rectangle grid_element_area(const GridElement& element) const;
+
+	private:
+		const uint32_t m_cols;
+		const uint32_t m_rows;
+		BAN::Vector<GridElement> m_grid_elements;
+	};
+
+}
diff --git a/userspace/libraries/LibGUI/include/LibGUI/Widget/Label.h b/userspace/libraries/LibGUI/include/LibGUI/Widget/Label.h
new file mode 100644
index 00000000..7b9d4db8
--- /dev/null
+++ b/userspace/libraries/LibGUI/include/LibGUI/Widget/Label.h
@@ -0,0 +1,44 @@
+#pragma once
+
+#include <BAN/StringView.h>
+
+#include <LibGUI/Widget/RoundedWidget.h>
+
+namespace LibGUI::Widget
+{
+
+	class Label : public RoundedWidget
+	{
+	public:
+		struct Style : RoundedWidget::Style
+		{
+			Style()
+				: RoundedWidget::Style()
+				, color_text(0x000000)
+			{}
+
+			uint32_t color_text;
+		};
+
+	public:
+		static BAN::ErrorOr<BAN::RefPtr<Label>> create(BAN::RefPtr<Widget> parent, BAN::StringView text, Rectangle geometry = {});
+
+		BAN::StringView text() const { return m_text; }
+		BAN::ErrorOr<void> set_text(BAN::StringView);
+
+		Style& style() { return m_style; }
+		const Style& style() const { return m_style; }
+
+	protected:
+		Label(BAN::RefPtr<Widget> parent, Rectangle area)
+			: RoundedWidget(parent, area)
+		{ }
+
+		void show_impl() override;
+
+	private:
+		Style m_style;
+		BAN::String m_text;
+	};
+
+}
diff --git a/userspace/libraries/LibGUI/include/LibGUI/Widget/RoundedWidget.h b/userspace/libraries/LibGUI/include/LibGUI/Widget/RoundedWidget.h
new file mode 100644
index 00000000..d86e46d4
--- /dev/null
+++ b/userspace/libraries/LibGUI/include/LibGUI/Widget/RoundedWidget.h
@@ -0,0 +1,42 @@
+#pragma once
+
+#include <LibGUI/Widget/Widget.h>
+
+namespace LibGUI::Widget
+{
+
+	class RoundedWidget : public Widget
+	{
+	public:
+		struct Style
+		{
+			Style(uint32_t color_normal = 0xA0A0A0, uint32_t border_width = 1, uint32_t color_border = 0x000000, uint32_t corner_radius = 5)
+				: color_normal(color_normal)
+				, border_width(border_width)
+				, color_border(color_border)
+				, corner_radius(corner_radius)
+			{}
+
+			uint32_t color_normal;
+			uint32_t border_width;
+			uint32_t color_border;
+			uint32_t corner_radius;
+		};
+
+		Style& style() { return m_style; }
+		const Style& style() const { return m_style; }
+
+	protected:
+		RoundedWidget(BAN::RefPtr<Widget> parent, Rectangle area)
+			: Widget(parent, area)
+		{ }
+
+		bool contains(Point point) const override;
+
+		void show_impl() override;
+
+	private:
+		Style m_style;
+	};
+
+}
diff --git a/userspace/libraries/LibGUI/include/LibGUI/Widget/TextArea.h b/userspace/libraries/LibGUI/include/LibGUI/Widget/TextArea.h
new file mode 100644
index 00000000..71729b2a
--- /dev/null
+++ b/userspace/libraries/LibGUI/include/LibGUI/Widget/TextArea.h
@@ -0,0 +1,50 @@
+#pragma once
+
+#include <BAN/StringView.h>
+
+#include <LibGUI/Widget/RoundedWidget.h>
+
+namespace LibGUI::Widget
+{
+
+	class TextArea : public RoundedWidget
+	{
+	public:
+		struct Style : RoundedWidget::Style
+		{
+			Style()
+				: RoundedWidget::Style()
+				, color_text(0x000000)
+			{}
+
+			uint32_t color_text;
+		};
+
+	public:
+		static BAN::ErrorOr<BAN::RefPtr<TextArea>> create(BAN::RefPtr<Widget> parent, BAN::StringView text, Rectangle geometry = {});
+
+		BAN::StringView text() const { return m_text; }
+		BAN::ErrorOr<void> set_text(BAN::StringView);
+
+		uint32_t get_required_height() const;
+
+		Style& style() { return m_style; }
+		const Style& style() const { return m_style; }
+
+	protected:
+		TextArea(BAN::RefPtr<Widget> parent, Rectangle area)
+			: RoundedWidget(parent, area)
+		{ }
+
+		BAN::ErrorOr<void> wrap_text();
+
+		BAN::ErrorOr<void> update_geometry_impl() override;
+		void show_impl() override;
+
+	private:
+		Style m_style;
+		BAN::String m_text;
+		BAN::Vector<BAN::String> m_wrapped_text;
+	};
+
+}
diff --git a/userspace/libraries/LibGUI/include/LibGUI/Widget/Widget.h b/userspace/libraries/LibGUI/include/LibGUI/Widget/Widget.h
new file mode 100644
index 00000000..8d0f0c22
--- /dev/null
+++ b/userspace/libraries/LibGUI/include/LibGUI/Widget/Widget.h
@@ -0,0 +1,163 @@
+#pragma once
+
+#include <BAN/RefPtr.h>
+
+#include <LibGUI/Texture.h>
+#include <LibGUI/Packet.h>
+
+namespace LibGUI { class Window; }
+
+namespace LibGUI::Widget
+{
+
+	class Widget : public BAN::RefCounted<Widget>
+	{
+	public:
+		static constexpr uint32_t color_invisible = Texture::color_invisible;
+
+		struct Point
+		{
+			int32_t x, y;
+		};
+
+		struct FloatRectangle
+		{
+			float x, y;
+			float w, h;
+		};
+
+		struct Rectangle
+		{
+			int32_t x, y;
+			uint32_t w, h;
+
+			struct Bounds
+			{
+				int32_t min_x, min_y;
+				int32_t max_x, max_y;
+			};
+
+			bool contains(Point point) const
+			{
+				if (point.x < x || point.x >= x + static_cast<int32_t>(w))
+					return false;
+				if (point.y < y || point.y >= y + static_cast<int32_t>(h))
+					return false;
+				return true;
+			}
+
+			Bounds bounds(Rectangle other) const
+			{
+				return Bounds {
+					.min_x = BAN::Math::max(x, other.x),
+					.min_y = BAN::Math::max(y, other.y),
+					.max_x = BAN::Math::min(x + static_cast<int32_t>(w), other.x + static_cast<int32_t>(other.w)),
+					.max_y = BAN::Math::min(y + static_cast<int32_t>(h), other.y + static_cast<int32_t>(other.h)),
+				};
+			};
+
+			Rectangle overlap(Rectangle other) const
+			{
+				const auto min_x = BAN::Math::max(x, other.x);
+				const auto min_y = BAN::Math::max(y, other.y);
+				const auto max_x = BAN::Math::min(x + static_cast<int32_t>(w), other.x + static_cast<int32_t>(other.w));
+				const auto max_y = BAN::Math::min(y + static_cast<int32_t>(h), other.y + static_cast<int32_t>(other.h));
+				if (min_x >= max_x || min_y >= max_y)
+					return {};
+				return Rectangle {
+					.x = min_x,
+					.y = min_y,
+					.w = static_cast<uint32_t>(max_x - min_x),
+					.h = static_cast<uint32_t>(max_y - min_y),
+				};
+			}
+
+			Rectangle bounding_box(Rectangle other) const
+			{
+				if (w == 0 || h == 0)
+					return other;
+				if (other.w == 0 || other.h == 0)
+					return *this;
+				const auto min_x = BAN::Math::min(x, other.x);
+				const auto min_y = BAN::Math::min(y, other.y);
+				const auto max_x = BAN::Math::max(x + static_cast<int32_t>(w), other.x + static_cast<int32_t>(other.w));
+				const auto max_y = BAN::Math::max(y + static_cast<int32_t>(h), other.y + static_cast<int32_t>(other.h));
+				return Rectangle {
+					.x = min_x,
+					.y = min_y,
+					.w = static_cast<uint32_t>(max_x - min_x),
+					.h = static_cast<uint32_t>(max_y - min_y),
+				};
+			}
+		};
+
+	public:
+		static BAN::ErrorOr<BAN::RefPtr<Widget>> create(BAN::RefPtr<Widget> parent, uint32_t color = color_invisible, Rectangle geometry = {});
+
+		static BAN::ErrorOr<void> set_default_font(BAN::StringView path);
+		static const LibFont::Font& default_font();
+
+		void show();
+		void hide();
+
+		BAN::ErrorOr<void> set_fixed_geometry(Rectangle);
+		BAN::ErrorOr<void> set_relative_geometry(FloatRectangle);
+
+		BAN::RefPtr<Widget> parent() { return m_parent; }
+
+		uint32_t width() const { return m_fixed_area.w; }
+		uint32_t height() const { return m_fixed_area.h; }
+
+	private:
+		void before_mouse_move();
+		void after_mouse_move();
+		bool on_mouse_move(LibGUI::EventPacket::MouseMoveEvent::event_t);
+
+		bool on_mouse_button(LibGUI::EventPacket::MouseButtonEvent::event_t);
+
+	protected:
+		Widget(BAN::RefPtr<Widget> parent, Rectangle area)
+			: m_parent(parent)
+			, m_fixed_area(area)
+		{ }
+
+		BAN::ErrorOr<void> initialize(uint32_t color);
+
+		virtual bool contains(Point point) const { return Rectangle { 0, 0, width(), height() }.contains(point); }
+
+		bool is_hovered() const { return m_hovered; }
+		bool is_child_hovered() const;
+
+		bool is_shown() const { return m_shown; }
+
+		Rectangle render(Texture& output, Point parent_position, Rectangle out_area);
+
+		virtual void update_impl() {}
+		virtual void show_impl() {}
+
+		virtual BAN::ErrorOr<void> update_geometry_impl();
+
+		virtual void on_hover_change_impl(bool hovered) { (void)hovered; }
+		virtual bool on_mouse_move_impl(LibGUI::EventPacket::MouseMoveEvent::event_t) { return true; }
+		virtual bool on_mouse_button_impl(LibGUI::EventPacket::MouseButtonEvent::event_t) { return true; }
+
+	protected:
+		Texture m_texture;
+
+	private:
+		BAN::RefPtr<Widget> m_parent;
+		BAN::Vector<BAN::RefPtr<Widget>> m_children;
+		bool m_shown { false };
+
+		Rectangle m_fixed_area;
+		BAN::Optional<FloatRectangle> m_relative_area;
+
+		bool m_changed { false };
+
+		bool m_hovered { false };
+		bool m_old_hovered { false };
+
+		friend class LibGUI::Window;
+	};
+
+}
diff --git a/userspace/libraries/LibGUI/include/LibGUI/Window.h b/userspace/libraries/LibGUI/include/LibGUI/Window.h
index c73f9dda..bcdc02f3 100644
--- a/userspace/libraries/LibGUI/include/LibGUI/Window.h
+++ b/userspace/libraries/LibGUI/include/LibGUI/Window.h
@@ -6,6 +6,7 @@
 
 #include <LibGUI/Packet.h>
 #include <LibGUI/Texture.h>
+#include <LibGUI/Widget/Widget.h>
 
 namespace LibFont { class Font; }
 
@@ -32,6 +33,9 @@ namespace LibGUI
 
 		static BAN::ErrorOr<BAN::UniqPtr<Window>> create(uint32_t width, uint32_t height, BAN::StringView title, Attributes attributes = default_attributes);
 
+		BAN::ErrorOr<void> set_root_widget(BAN::RefPtr<Widget::Widget> widget);
+		BAN::RefPtr<Widget::Widget> root_widget() { return m_root_widget; }
+
 		Texture& texture() { return m_texture; }
 		const Texture& texture() const { return m_texture; }
 
@@ -94,6 +98,7 @@ namespace LibGUI
 		uint32_t m_height { 0 };
 
 		Texture m_texture;
+		BAN::RefPtr<Widget::Widget> m_root_widget;
 
 		BAN::Function<void()>                                       m_socket_error_callback;
 		BAN::Function<void()>                                       m_close_window_event_callback;