From 374bb1f45bed3d21ad9abd7343bf0d2fc8a56fbc Mon Sep 17 00:00:00 2001
From: Manuel Nickschas <sputnick@quassel-irc.org>
Date: Thu, 8 Mar 2018 00:22:24 +0100
Subject: [PATCH] uistyle: Support reverse color rendering

Format codes 0x12 and 0x16 toggle the swap of foreground and
background colors. In the current implementation, the color
swap only applies to custom colors, i.e. mIRC colors and hex
colors. Normal text is not affected.

Since this is not a styleable property, remove support for it
from the stylesheet parser.
---
 src/uisupport/qssparser.cpp |  2 --
 src/uisupport/uistyle.cpp   | 20 ++++++++++++++------
 src/uisupport/uistyle.h     |  1 -
 3 files changed, 14 insertions(+), 9 deletions(-)

diff --git a/src/uisupport/qssparser.cpp b/src/uisupport/qssparser.cpp
index d1a13e8f..07dab3a8 100644
--- a/src/uisupport/qssparser.cpp
+++ b/src/uisupport/qssparser.cpp
@@ -322,8 +322,6 @@ std::pair<UiStyle::FormatType, UiStyle::MessageLabel> QssParser::parseFormatType
                     fmtType |= FormatType::Italic;
                 else if (condValue == "underline")
                     fmtType |= FormatType::Underline;
-                else if (condValue == "reverse")
-                    fmtType |= FormatType::Reverse;
                 else {
                     qWarning() << Q_FUNC_INFO << tr("Invalid format name: %1").arg(condValue);
                     return invalid;
diff --git a/src/uisupport/uistyle.cpp b/src/uisupport/uistyle.cpp
index d913fc9b..bd9b013c 100644
--- a/src/uisupport/uistyle.cpp
+++ b/src/uisupport/uistyle.cpp
@@ -18,6 +18,7 @@
  *   51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.         *
  ***************************************************************************/
 
+#include <utility>
 #include <vector>
 
 #include <QApplication>
@@ -86,7 +87,6 @@ UiStyle::UiStyle(QObject *parent)
     _formatCodes["%B"] = FormatType::Bold;
     _formatCodes["%S"] = FormatType::Italic;
     _formatCodes["%U"] = FormatType::Underline;
-    _formatCodes["%R"] = FormatType::Reverse;
 
     _formatCodes["%DN"] = FormatType::Nick;
     _formatCodes["%DH"] = FormatType::Hostmask;
@@ -639,6 +639,7 @@ UiStyle::StyledString UiStyle::styleString(const QString &s_, FormatType baseFor
     }
 
     Format curfmt{baseFormat, {}, {}};
+    QChar fgChar{'f'}; // character to indicate foreground color, changed when reversing
 
     int pos = 0; quint16 length = 0;
     for (;;) {
@@ -660,7 +661,7 @@ UiStyle::StyledString UiStyle::styleString(const QString &s_, FormatType baseFor
                 quint32 color = 10 * s[pos+4].digitValue() + s[pos+5].digitValue();
                 // Color values 0-15 are traditional mIRC colors, defined in the stylesheet and thus going through the format engine
                 // Larger color values are hardcoded and applied separately (cf. https://modern.ircdocs.horse/formatting.html#colors-16-98)
-                if (s[pos+3] == 'f') {
+                if (s[pos+3] == fgChar) {
                     if (color < 16) {
                         // Traditional mIRC color, defined in the stylesheet
                         curfmt.type &= 0xf0ffffff;
@@ -688,7 +689,7 @@ UiStyle::StyledString UiStyle::styleString(const QString &s_, FormatType baseFor
         }
         else if (s[pos+1] == 'D' && s[pos+2] == 'h') { // Hex color
             QColor color{s.mid(pos+4, 7)};
-            if (s[pos+3] == 'f') {
+            if (s[pos+3] == fgChar) {
                 curfmt.type &= 0xf0bfffff;  // mask out mIRC foreground color
                 curfmt.foreground = std::move(color);
             }
@@ -702,11 +703,18 @@ UiStyle::StyledString UiStyle::styleString(const QString &s_, FormatType baseFor
             curfmt.type &= 0x000000ff; // we keep message type-specific formatting
             curfmt.foreground = QColor{};
             curfmt.background = QColor{};
+            fgChar = 'f';
             length = 2;
         }
-        else if (s[pos+1] == 'R') { // reverse
-            // TODO: implement reverse formatting
-
+        else if (s[pos+1] == 'R') { // Reverse colors
+            fgChar = (fgChar == 'f' ? 'b' : 'f');
+            quint32 orig = static_cast<quint32>(curfmt.type & 0xffc00000);
+            curfmt.type &= 0x003fffff;
+            curfmt.type |= (orig & 0x00400000) <<1;
+            curfmt.type |= (orig & 0x0f000000) <<4;
+            curfmt.type |= (orig & 0x00800000) >>1;
+            curfmt.type |= (orig & 0xf0000000) >>4;
+            std::swap(curfmt.foreground, curfmt.background);
             length = 2;
         }
         else { // all others are toggles
diff --git a/src/uisupport/uistyle.h b/src/uisupport/uistyle.h
index f0618bbb..35d9eeeb 100644
--- a/src/uisupport/uistyle.h
+++ b/src/uisupport/uistyle.h
@@ -81,7 +81,6 @@ public:
         Bold            = 0x00000100,
         Italic          = 0x00000200,
         Underline       = 0x00000400,
-        Reverse         = 0x00000800,
 
         // Individual parts of a message
         Timestamp       = 0x00001000,
-- 
2.20.1