From 7d4452f45cf672bb77beb42178e5d78d66c55e94 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Henrik=20Ga=C3=9Fmann?=
 <BurningEnlightenment@users.noreply.github.com>
Date: Tue, 14 Sep 2021 14:22:30 +0200
Subject: [PATCH] Add an UDL for combined hex RGB colors (#203)

In order to allow using the literal on its own it has been put into the
inline namespace `literals`.
---
 examples/dom/style_color.cpp   |  6 ++++--
 include/ftxui/screen/color.hpp | 10 +++++++++-
 src/ftxui/screen/color.cpp     | 14 ++++++++++++++
 3 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/examples/dom/style_color.cpp b/examples/dom/style_color.cpp
index 6a626cd..6f42bd1 100644
--- a/examples/dom/style_color.cpp
+++ b/examples/dom/style_color.cpp
@@ -28,7 +28,8 @@ int main(int argc, const char* argv[]) {
         color(Color::Red, text("Red")),
         color(Color::RedLight, text("RedLight")),
         color(Color::Yellow, text("Yellow")),
-        color(Color::YellowLight, text("YellowLight"))
+        color(Color::YellowLight, text("YellowLight")),
+        color(0x66ff66_rgb, text("Phosphor"))
       ),
       vbox(
         bgcolor(Color::Default, text("Default")),
@@ -47,7 +48,8 @@ int main(int argc, const char* argv[]) {
         bgcolor(Color::Red, text("Red")),
         bgcolor(Color::RedLight, text("RedLight")),
         bgcolor(Color::Yellow, text("Yellow")),
-        bgcolor(Color::YellowLight, text("YellowLight"))
+        bgcolor(Color::YellowLight, text("YellowLight")),
+        bgcolor(0x66ff66_rgb, text("Phosphor"))
       ),
       filler()
     );
diff --git a/include/ftxui/screen/color.hpp b/include/ftxui/screen/color.hpp
index 521c7cd..8ebd59a 100644
--- a/include/ftxui/screen/color.hpp
+++ b/include/ftxui/screen/color.hpp
@@ -2,7 +2,7 @@
 #define FTXUI_SCREEN_COLOR
 
 #include <stdint.h>  // for uint8_t
-#include <string>    // for wstring
+#include <string>  // for wstring
 
 #ifdef RGB
 // Workaround for wingdi.h (via Windows.h) defining macros that break things.
@@ -322,6 +322,14 @@ class Color {
   uint8_t blue_ = 0;
 };
 
+inline namespace literals {
+
+/// @brief Creates a color from a combined hex RGB representation, 
+/// e.g. 0x808000_rgb
+Color operator""_rgb(unsigned long long int combined);
+
+}  // namespace literals
+
 }  // namespace ftxui
 
 #endif /* end of include guard: FTXUI_COLOR_H_ */
diff --git a/src/ftxui/screen/color.cpp b/src/ftxui/screen/color.cpp
index ed92e13..bf402e7 100644
--- a/src/ftxui/screen/color.cpp
+++ b/src/ftxui/screen/color.cpp
@@ -1,5 +1,7 @@
 #include "ftxui/screen/color.hpp"
 
+#include <cassert>
+
 #include "ftxui/screen/color_info.hpp"  // for GetColorInfo, ColorInfo
 #include "ftxui/screen/terminal.hpp"  // for Terminal, Terminal::Color, Terminal::Palette256, Terminal::TrueColor
 
@@ -143,6 +145,18 @@ Color Color::HSV(uint8_t h, uint8_t s, uint8_t v) {
   return Color(0, 0, 0);
 }
 
+inline namespace literals {
+
+Color operator""_rgb(unsigned long long int combined) {
+  assert(combined <= 0xffffffU);
+  auto const red = static_cast<uint8_t>(combined >> 16);
+  auto const green = static_cast<uint8_t>(combined >> 8);
+  auto const blue = static_cast<uint8_t>(combined);
+  return Color(red, green, blue);
+}
+
+}  // namespace literals
+
 }  // namespace ftxui
 
 // Copyright 2020 Arthur Sonzogni. All rights reserved.