Add custom theme support with wallpaper-based color extraction (#6)

* Add custom theme support with wallpaper-based color extraction

- Extended theme option to accept "custom" value
- Added customTheme configuration with wallpaperPath and variant options
- Integrated nix-colors colorSchemeFromPicture for dynamic color generation
- Updated wallpaper selection to handle custom paths
- Added VSCode theme fallback for custom color schemes
- Fixed nix-colors contrib function call (requires pkgs argument)
- Maintains full backward compatibility with existing themes

Users can now generate themes from their own wallpapers:
  omarchy = {
    theme = "custom";
    customTheme = {
      wallpaperPath = ./wallpapers/my-image.png;
      variant = "dark"; # or "light"
    };
  };

* Fix: Screen sharing broken due to Qt library version mismatch

  File changed: modules/nixos/hyprland.nix

  Problem:
  The omarchy-nix configuration was using xdg-desktop-portal-hyprland from the hyprland flake input, which had a Qt library version mismatch (6.9.1 vs 6.9.0). This caused the
   hyprland-share-picker to crash with "Cannot mix incompatible Qt library" errors, preventing screen sharing from working.

  Solution:
  Changed the portalPackage from the hyprland flake version to the stable nixpkgs version:

  - portalPackage = inputs.hyprland.packages.${pkgs.stdenv.hostPlatform.system}.xdg-desktop-portal-hyprland;
  + portalPackage = pkgs.xdg-desktop-portal-hyprland; # Use stable nixpkgs version to fix Qt version mismatch

  Why this works:
  - The stable nixpkgs version of xdg-desktop-portal-hyprland has consistent Qt library versions
  - This matches the working configuration used on other NixOS Hyprland setups
  - Maintains all screen sharing functionality while avoiding the Qt version conflict

README.md

@@ -58,6 +58,33 @@ I've specified some basic configuration options to help you get started with ini
 
 Refer to [the root configuration](https://github.com/henrysipp/omarchy-nix/blob/main/config.nix) file for more information on what options are available.
 
+### Themes
+
+Omarchy-nix includes several predefined themes:
+- `tokyo-night` (default)
+- `kanagawa`
+- `everforest`
+- `catppuccin`
+- `nord`
+- `gruvbox`
+- `gruvbox-light`
+
+You can also generate a custom theme from any wallpaper image:
+
+```nix
+{
+  omarchy = {
+    theme = "custom";
+    customTheme = {
+      wallpaperPath = ./path/to/your/wallpaper.png;
+      variant = "dark"; # or "light" for light themes
+    };
+  };
+}
+```
+
+This will automatically extract colors from your wallpaper and generate a matching color scheme for all Omarchy applications (terminal, editor, launcher, etc.). 
+
 ## License
 
 This project is released under the MIT License, same as the original Omarchy.

config.nix

@@ -9,7 +9,7 @@ lib: {
       description = "Main user's email address";
     };
     theme = lib.mkOption {
-      type = lib.types.enum [
+      type = lib.types.either (lib.types.enum [
         "tokyo-night"
         "kanagawa"
         "everforest"
@@ -17,10 +17,28 @@ lib: {
         "nord"
         "gruvbox"
         "gruvbox-light"
-      ];
+        "custom"
+      ]) lib.types.str;
       default = "tokyo-night";
       description = "Theme to use for Omarchy configuration";
     };
+    customTheme = lib.mkOption {
+      type = lib.types.submodule {
+        options = {
+          wallpaperPath = lib.mkOption {
+            type = lib.types.path;
+            description = "Path to the wallpaper image to extract colors from";
+          };
+          variant = lib.mkOption {
+            type = lib.types.enum [ "light" "dark" ];
+            default = "dark";
+            description = "Color scheme variant to extract (light or dark)";
+          };
+        };
+      };
+      default = {};
+      description = "Custom theme configuration when theme is set to 'custom'";
+    };
     primary_font = lib.mkOption {
       type = lib.types.str;
       default = "Liberation Sans 11";

lib/selected-wallpaper.nix

@@ -21,7 +21,12 @@ config: let
     ];
   };
 
-  selected_wallpaper = builtins.elemAt (wallpapers.${cfg.theme}) 0;
+  # Handle custom wallpaper path
+  wallpaper_path = if cfg.theme == "custom"
+    then toString cfg.customTheme.wallpaperPath
+    else let
+      selected_wallpaper = builtins.elemAt (wallpapers.${cfg.theme}) 0;
+    in "~/Pictures/Wallpapers/${selected_wallpaper}";
 in {
-  wallpaper_path = "~/Pictures/Wallpapers/${selected_wallpaper}";
+  inherit wallpaper_path;
 }

modules/home-manager/default.nix

@@ -7,7 +7,19 @@ inputs: {
   packages = import ../packages.nix {inherit pkgs lib; exclude_packages = config.omarchy.exclude_packages;};
 
   themes = import ../themes.nix;
-  selectedTheme = themes.${config.omarchy.theme};
+  
+  # Handle theme selection - either predefined or custom
+  selectedTheme = if config.omarchy.theme == "custom"
+    then themes.custom
+    else themes.${config.omarchy.theme};
+  
+  # Generate color scheme - either from predefined or from wallpaper
+  generatedColorScheme = if config.omarchy.theme == "custom"
+    then (inputs.nix-colors.lib.contrib { inherit pkgs; }).colorSchemeFromPicture {
+      path = config.omarchy.customTheme.wallpaperPath;
+      variant = config.omarchy.customTheme.variant;
+    }
+    else null;
 in {
   imports = [
     (import ./hyprland.nix inputs)
@@ -35,7 +47,9 @@ in {
   };
   home.packages = packages.homePackages;
 
-  colorScheme = inputs.nix-colors.colorSchemes.${selectedTheme.base16-theme};
+  colorScheme = if config.omarchy.theme == "custom"
+    then generatedColorScheme
+    else inputs.nix-colors.colorSchemes.${selectedTheme.base16-theme};
 
   gtk = {
     enable = true;

modules/nixos/hyprland.nix

@@ -7,6 +7,6 @@ inputs: {
     enable = true;
     # package = inputs.hyprland.packages.${pkgs.system}.hyprland;
     package = inputs.hyprland.packages.${pkgs.stdenv.hostPlatform.system}.hyprland;
-    portalPackage = inputs.hyprland.packages.${pkgs.stdenv.hostPlatform.system}.xdg-desktop-portal-hyprland;
+    portalPackage = pkgs.xdg-desktop-portal-hyprland; # Use stable nixpkgs version to fix Qt version mismatch
   };
 }

modules/themes.nix

@@ -29,5 +29,11 @@
     base16-theme = "gruvbox-light-medium";
     vscode-theme = "Gruvbox Light Medium";
   };
+  
+  "custom" = {
+    # Custom themes don't have predefined base16 schemes (generated dynamically)
+    # VSCode theme fallback for custom color schemes
+    vscode-theme = "Tokyo Night"; # Default fallback theme
+  };
   # Add more themes here
 }