From 32376992f7ef4d7ae76dda690de5b23725fd8300 Mon Sep 17 00:00:00 2001
From: Thiago Kenji Okada <thiagokokada@gmail.com>
Date: Wed, 14 Jun 2023 19:16:20 +0000
Subject: [PATCH] qt: add "kde" to qt.platformTheme (#4085)

This allow you to configure Qt integration using KDE instead of
qgnomeplatform or qtstyleplugins. Useful if your theme supports both GTK
and KDE, for example Nordic.

To use this properly you will need to do some manual configuration for
now. You can set the theme settings using `~/.config/kdeglobals`.

Example:

```nix
{ ... }:
{
  qt = {
    enable = true;
    platformTheme = "kde";
  };

  xdg = {
    configFile.kdeglobals.text = lib.generators.toINI { } {
      General = {
        ColorScheme = "nordicbluish";
        Name = "nordic-bluish";
        shadeSortColumn = true;
      };
      Icons = {
        Theme = "Nordic-bluish";
      };
      KDE = {
        LookAndFeelPackage = "Nordic-bluish";
        contrast = 4;
      };
    };

    dataFile = {
      # For General.ColorScheme
      color-schemes = {
        source = "${pkgs.nordic}/share/color-schemes";
        recursive = true;
      };
      # For KDE.LookAndFeelPackage
      plasma = {
        source = "${pkgs.nordic}/share/plasma";
        recursive = true;
      };
    };
  };
}
```
---
 modules/misc/qt.nix | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/modules/misc/qt.nix b/modules/misc/qt.nix
index 4c289522f..cdc0283d6 100644
--- a/modules/misc/qt.nix
+++ b/modules/misc/qt.nix
@@ -38,7 +38,7 @@ in {
       enable = mkEnableOption "Qt 4 and 5 configuration";
 
       platformTheme = mkOption {
-        type = types.nullOr (types.enum [ "gtk" "gnome" ]);
+        type = types.nullOr (types.enum [ "gtk" "gnome" "kde" ]);
         default = null;
         example = "gnome";
         relatedPackages =
@@ -59,6 +59,10 @@ in {
                 <link xlink:href="https://github.com/FedoraQt/QGnomePlatform">qgnomeplatform</link>
               </para></listitem>
             </varlistentry>
+            <varlistentry>
+              <term><literal>kde</literal></term>
+              <listitem><para>Use Qt settings from Plasma</para></listitem>
+            </varlistentry>
           </variablelist>
         '';
       };
@@ -134,14 +138,17 @@ in {
     # Necessary because home.sessionVariables doesn't support mkIf
     home.sessionVariables = filterAttrs (n: v: v != null) {
       QT_QPA_PLATFORMTHEME =
-        if cfg.platformTheme == "gnome" then "gnome" else "gtk2";
+        if cfg.platformTheme == "gtk" then "gtk2" else cfg.platformTheme;
       QT_STYLE_OVERRIDE = cfg.style.name;
     };
 
     home.packages = if cfg.platformTheme == "gnome" then
       [ pkgs.qgnomeplatform ]
       ++ lib.optionals (cfg.style.package != null) [ cfg.style.package ]
-    else
+    else if cfg.platformTheme == "kde" then [
+      pkgs.libsForQt5.plasma-integration
+      pkgs.libsForQt5.systemsettings
+    ] else
       [ pkgs.libsForQt5.qtstyleplugins ];
 
     xsession.importedVariables = [ "QT_QPA_PLATFORMTHEME" ]