From 69bd54684854674affc77cee522812f630d3df46 Mon Sep 17 00:00:00 2001
From: lisyarus <lisyarus@gmail.com>
Date: Thu, 25 Feb 2021 11:42:47 +0300
Subject: [PATCH] Label implementation wip

---
 examples/ui.cpp                            |  1 +
 libs/ui/include/psemek/ui/label.hpp        | 15 +++++++
 libs/ui/include/psemek/ui/style.hpp        |  4 ++
 libs/ui/source/default_element_factory.cpp |  7 ++++
 libs/ui/source/label.cpp                   | 47 +++++++++++++++++++++-
 5 files changed, 72 insertions(+), 2 deletions(-)

diff --git a/examples/ui.cpp b/examples/ui.cpp
index cbadb121..1478bb8f 100644
--- a/examples/ui.cpp
+++ b/examples/ui.cpp
@@ -19,6 +19,7 @@ struct ui_example
 	{
 		auto style = std::make_shared<ui::style>();
 		style->font = ui::make_default_9x12_font();
+		style->text_scale = 2;
 		element_factory.set_style(style);
 
 		auto screen = element_factory.make_screen();
diff --git a/libs/ui/include/psemek/ui/label.hpp b/libs/ui/include/psemek/ui/label.hpp
index daa65415..0485ef32 100644
--- a/libs/ui/include/psemek/ui/label.hpp
+++ b/libs/ui/include/psemek/ui/label.hpp
@@ -1,6 +1,7 @@
 #pragma once
 
 #include <psemek/ui/element.hpp>
+#include <psemek/ui/box_shape.hpp>
 
 #include <string>
 #include <string_view>
@@ -54,6 +55,10 @@ namespace psemek::ui
 		virtual void set_overflow(overflow_mode value);
 		virtual overflow_mode overflow() const { return overflow_; }
 
+		struct shape const & shape() const override { return shape_; }
+		void reshape(geom::box<float, 2> const & bbox) override;
+		void draw(painter & p) const override;
+
 	protected:
 		virtual void on_state_changed();
 
@@ -63,6 +68,16 @@ namespace psemek::ui
 		valignment valign_;
 		multiline_mode multiline_;
 		overflow_mode overflow_;
+
+		box_shape shape_;
+
+		struct cached_state
+		{
+			struct font const * font = nullptr;
+			std::vector<glyph> glyphs;
+		};
+
+		mutable std::optional<cached_state> cached_state_;
 	};
 
 }
diff --git a/libs/ui/include/psemek/ui/style.hpp b/libs/ui/include/psemek/ui/style.hpp
index ccdb6a7d..b04c5582 100644
--- a/libs/ui/include/psemek/ui/style.hpp
+++ b/libs/ui/include/psemek/ui/style.hpp
@@ -19,7 +19,11 @@ namespace psemek::ui
 		geom::vector<int, 2> shadow_offset{1, 1};
 		gfx::color_rgba shadow_color{0, 0, 0, 255};
 
+		int inner_margin = 5;
+		int outer_margin = 10;
+
 		gfx::color_rgba text_color{0, 0, 0, 255};
+		int text_scale = 1;
 		std::shared_ptr<struct font> font;
 	};
 
diff --git a/libs/ui/source/default_element_factory.cpp b/libs/ui/source/default_element_factory.cpp
index df784584..29494dab 100644
--- a/libs/ui/source/default_element_factory.cpp
+++ b/libs/ui/source/default_element_factory.cpp
@@ -14,6 +14,10 @@ namespace psemek::ui
 			button_impl()
 			{
 				set_label(std::make_unique<struct label>());
+				label()->set_valign(label::valignment::center);
+				label()->set_halign(label::halignment::center);
+				label()->set_overflow(label::overflow_mode::drop);
+				label()->set_multiline(label::multiline_mode::none);
 			}
 
 			struct shape const & shape() const override
@@ -24,6 +28,8 @@ namespace psemek::ui
 			void reshape(geom::box<float, 2> const & bbox) override
 			{
 				shape_.box = bbox;
+				auto s = style();
+				if (s && label()) label()->reshape(geom::shrink(bbox, 1.f * (s->border_width + s->inner_margin)));
 			}
 
 			void draw(painter & p) const override
@@ -95,6 +101,7 @@ namespace psemek::ui
 	{
 		auto r = impl().create<button_impl>();
 		r->label()->set_text(std::move(text));
+		r->label()->set_style(impl().style);
 		return r;
 	}
 
diff --git a/libs/ui/source/label.cpp b/libs/ui/source/label.cpp
index 087bca2c..529f4b82 100644
--- a/libs/ui/source/label.cpp
+++ b/libs/ui/source/label.cpp
@@ -3,8 +3,6 @@
 namespace psemek::ui
 {
 
-	// TODO: changes should notify parent about content change
-
 	void label::set_text(std::string text)
 	{
 		text_ = std::move(text);
@@ -35,4 +33,49 @@ namespace psemek::ui
 		on_state_changed();
 	}
 
+	void label::reshape(geom::box<float, 2> const & bbox)
+	{
+		shape_.box = bbox;
+		cached_state_.reset();
+	}
+
+	void label::draw(painter & p) const
+	{
+		if (text_.empty()) return;
+
+		auto st = style();
+		if (!st) return;
+		if (!st->font) return;
+
+		if (!cached_state_ || cached_state_->font != st->font.get())
+		{
+			cached_state_ = cached_state{};
+			cached_state_->font = st->font.get();
+
+			shape_options opts;
+			opts.scale = st->text_scale;
+			cached_state_->glyphs = st->font->shape(text_, opts);
+
+			geom::box<float, 2> bbox;
+			for (auto const & g : cached_state_->glyphs)
+				bbox |= g.position;
+
+			geom::vector<float, 2> offset;
+			offset[0] = shape_.box[0].center() - bbox[0].length() / 2.f;
+			offset[1] = shape_.box[1].center() - st->text_scale * st->font->size()[1] / 2.f;
+
+			for (auto & g : cached_state_->glyphs)
+				g.position += offset;
+		}
+
+		for (auto & g : cached_state_->glyphs)
+			p.draw_rect(g.position, st->text_color);
+	}
+
+	void label::on_state_changed()
+	{
+		// TODO: changes should notify parent about content change
+		element::reshape();
+	}
+
 }