From f754fa27103e0df9a10b0083babd7ad29605e016 Mon Sep 17 00:00:00 2001
From: Michael Carlberg <c@rlberg.se>
Date: Tue, 25 Apr 2017 20:26:48 +0200
Subject: [PATCH] feat(parser): Keep track of formatting colors #544

---
 include/components/parser.hpp |  8 ++++++++
 src/components/parser.cpp     | 28 ++++++++++++++++++++++------
 2 files changed, 30 insertions(+), 6 deletions(-)

diff --git a/include/components/parser.hpp b/include/components/parser.hpp
index 8aeba5c0..993cd59e 100644
--- a/include/components/parser.hpp
+++ b/include/components/parser.hpp
@@ -1,5 +1,7 @@
 #pragma once
 
+#include <stack>
+
 #include "common.hpp"
 #include "errors.hpp"
 
@@ -28,6 +30,7 @@ class parser {
   void codeblock(string&& data, const bar_settings& bar);
   size_t text(string&& data);
 
+  unsigned int color(std::stack<unsigned int>& color_stack, string& value, unsigned int fallback);
   unsigned int parse_color(const string& s, unsigned int fallback = 0);
   int parse_fontindex(const string& s);
   attribute parse_attr(const char attr);
@@ -38,6 +41,11 @@ class parser {
   signal_emitter& m_sig;
   vector<int> m_actions;
   unique_ptr<parser> m_parser;
+
+  std::stack<unsigned int> m_fg;
+  std::stack<unsigned int> m_bg;
+  std::stack<unsigned int> m_ul;
+  std::stack<unsigned int> m_ol;
 };
 
 POLYBAR_NS_END
diff --git a/src/components/parser.cpp b/src/components/parser.cpp
index f30e5802..7efc9f9d 100644
--- a/src/components/parser.cpp
+++ b/src/components/parser.cpp
@@ -76,13 +76,15 @@ void parser::codeblock(string&& data, const bar_settings& bar) {
     }
 
     switch (tag) {
-      case 'B':
-        m_sig.emit(change_background{parse_color(value, 0)});
+      case 'B': {
+        m_sig.emit(change_background{color(m_bg, value, 0UL)});
         break;
+      }
 
-      case 'F':
-        m_sig.emit(change_foreground{parse_color(value, bar.foreground)});
+      case 'F': {
+        m_sig.emit(change_foreground{color(m_fg, value, bar.foreground)});
         break;
+      }
 
       case 'T':
         m_sig.emit(change_font{parse_fontindex(value)});
@@ -94,11 +96,11 @@ void parser::codeblock(string&& data, const bar_settings& bar) {
         break;
 
       case 'u':
-        m_sig.emit(change_underline{parse_color(value, bar.underline.color)});
+        m_sig.emit(change_underline{color(m_ul, value, bar.underline.color)});
         break;
 
       case 'o':
-        m_sig.emit(change_overline{parse_color(value, bar.overline.color)});
+        m_sig.emit(change_underline{color(m_ul, value, bar.overline.color)});
         break;
 
       case 'R':
@@ -177,6 +179,20 @@ size_t parser::text(string&& data) {
   return data.size();
 }
 
+/**
+ * Determine color using passed stack and input value
+ */
+unsigned int parser::color(std::stack<unsigned int>& color_stack, string& value, unsigned int fallback) {
+  if (!color_stack.empty() && !value.empty() && value[0] == '-') {
+    color_stack.pop();
+  }
+  auto parsed_value = parse_color(value, !color_stack.empty() ? color_stack.top() : fallback);
+  if (!value.empty() && value[0] != '-') {
+    color_stack.push(parsed_value);
+  }
+  return parsed_value;
+}
+
 /**
  * Process color hex string and convert it to the correct value
  */