From 4566b40de51f842849195417b6d7558b69da8f29 Mon Sep 17 00:00:00 2001
From: Anthony Rodriguez <anthony@nezia.dev>
Date: Tue, 1 Oct 2024 17:53:23 +0200
Subject: [PATCH] lib: add custom overlay with function to build konsole
 colorscheme

---
 lib/default.nix        | 98 ++++++++++++++++++++++++++++++++++++++++++
 system/nix/nixpkgs.nix | 15 ++++++-
 2 files changed, 111 insertions(+), 2 deletions(-)
 create mode 100644 lib/default.nix

diff --git a/lib/default.nix b/lib/default.nix
new file mode 100644
index 0000000..cd61e0f
--- /dev/null
+++ b/lib/default.nix
@@ -0,0 +1,98 @@
+{
+  pkgs,
+  lib,
+  ...
+}: let
+  # Helper function to convert hex color to decimal RGB values
+  hexToDec = v: let
+    hexToInt = {
+      "0" = 0;
+      "1" = 1;
+      "2" = 2;
+      "3" = 3;
+      "4" = 4;
+      "5" = 5;
+      "6" = 6;
+      "7" = 7;
+      "8" = 8;
+      "9" = 9;
+      "a" = 10;
+      "b" = 11;
+      "c" = 12;
+      "d" = 13;
+      "e" = 14;
+      "f" = 15;
+      "A" = 10;
+      "B" = 11;
+      "C" = 12;
+      "D" = 13;
+      "E" = 14;
+      "F" = 15;
+    };
+    chars = lib.strings.stringToCharacters v;
+    charsLen = builtins.length chars;
+  in
+    lib.lists.foldl (a: v: a + v) 0
+    (lib.lists.imap0 (k: v: hexToInt."${v}" * (pow 16 (charsLen - k - 1))) chars);
+
+  # Power function for exponentiation
+  pow = let
+    pow' = base: exponent: value:
+      if exponent == 0
+      then 1
+      else if exponent <= 1
+      then value
+      else pow' base (exponent - 1) (value * base);
+  in
+    base: exponent: pow' base exponent base;
+
+  # Converts hex color to KDE color format
+  colorToKde = name: hexColor: let
+    r = hexToDec (builtins.substring 0 2 hexColor);
+    g = hexToDec (builtins.substring 2 2 hexColor);
+    b = hexToDec (builtins.substring 4 2 hexColor);
+  in "[${name}]\nColor=${toString r},${toString g},${toString b}\n";
+
+  # Mapping base16 colors to KDE color scheme sections
+  schemeToKonsole = scheme: let
+    inherit (scheme) palette;
+
+    colorMap = {
+      base00 = ["Background" "BackgroundFaint" "BackgroundIntense"];
+      base01 = ["Color0"];
+      base02 = ["Color0Intense"];
+      base04 = ["Color4"];
+      base05 = ["Foreground" "ForegroundFaint" "ForegroundIntense"];
+      base06 = ["Color7"];
+      base07 = ["Color7Intense"];
+      base08 = ["Color1" "Color1Intense"];
+      base09 = ["Color1Intense"];
+      base0A = ["Color3" "Color3Intense"];
+      base0B = ["Color2" "Color2Intense"];
+      base0C = ["Color6" "Color6Intense"];
+      base0D = ["Color4" "Color4Intense"];
+      base0E = ["Color5" "Color5Intense"];
+    };
+
+    # Generate KDE color sections using the mapped colors
+    colorSections = lib.concatStringsSep "\n" (lib.attrsets.mapAttrsToList
+      (
+        name: value:
+          lib.concatMapStrings (slot: colorToKde slot value) (colorMap.${name} or [])
+      )
+      palette);
+  in
+    lib.strings.concatStringsSep "\n" (
+      [
+        "[General]"
+        "\nDescription=${scheme.name}"
+        "\nOpacity=1"
+        "\nWallpaper="
+      ]
+      ++ [colorSections]
+    );
+
+  # Main function to create the KDE colorscheme file
+  mkKonsoleColorScheme = scheme:
+    pkgs.writeText "${scheme.name}.colorscheme" (schemeToKonsole scheme);
+in {inherit mkKonsoleColorScheme;}
diff --git a/system/nix/nixpkgs.nix b/system/nix/nixpkgs.nix
index e95ec3c..c1f61f3 100644
--- a/system/nix/nixpkgs.nix
+++ b/system/nix/nixpkgs.nix
@@ -1,3 +1,14 @@
-{
-  nixpkgs.config.allowUnfree = true;
+_: {
+  nixpkgs = {
+    config.allowUnfree = true;
+    overlays = [
+      (_: prev: {
+        lib =
+          prev.lib
+          // import ../../lib {
+            inherit (prev) lib pkgs;
+          };
+      })
+    ];
+  };
 }