tv xmonad: read screen/font width from build env

tv/2configs/xserver/default.nix

@@ -6,6 +6,12 @@ let
     configDir = "/var/empty";
     dataDir = "/run/xdg/${cfg.user.name}/xmonad";
     user = config.krebs.build.user;
+    xmonad.pkg = pkgs.haskellPackages.xmonad-tv.overrideAttrs (_: {
+      XMONAD_BUILD_SCREEN_WIDTH = 1366;
+      XMONAD_BUILD_TERM_FONT_WIDTH = 6;
+      XMONAD_BUILD_TERM_FONT = "-*-clean-*-*-*-*-*-*-*-*-*-*-iso10646-1";
+      XMONAD_BUILD_TERM_PADDING = 2;
+    });
   };
 in {
 
@@ -51,7 +57,7 @@ in {
   systemd.services.display-manager.enable = false;
 
   systemd.services.xmonad = let
-    xmonad = "${pkgs.haskellPackages.xmonad-tv}/bin/xmonad";
+    xmonad = "${cfg.xmonad.pkg}/bin/xmonad";
     xmonad-start = pkgs.writeDash "xmonad-start" ''
       ${pkgs.coreutils}/bin/mkdir -p "$XMONAD_CACHE_DIR"
       ${pkgs.coreutils}/bin/mkdir -p "$XMONAD_CONFIG_DIR"

tv/5pkgs/haskell/xmonad-tv/default.nix

@@ -1,5 +1,6 @@
-{ mkDerivation, base, containers, directory, extra, stdenv, unix
+{ mkDerivation, aeson, base, bytestring, containers, directory
-, X11, xmonad, xmonad-contrib, xmonad-stockholm
+, extra, stdenv, template-haskell, th-env, unix, X11, xmonad
+, xmonad-contrib, xmonad-stockholm
 }:
 mkDerivation {
   pname = "xmonad-tv";
@@ -8,8 +9,8 @@ mkDerivation {
   isLibrary = false;
   isExecutable = true;
   executableHaskellDepends = [
-    base containers directory extra unix X11 xmonad xmonad-contrib
+    aeson base bytestring containers directory extra template-haskell
-    xmonad-stockholm
+    th-env unix X11 xmonad xmonad-contrib xmonad-stockholm
   ];
   license = stdenv.lib.licenses.mit;
 }

tv/5pkgs/haskell/xmonad-tv/src/THEnv/JSON.hs

@@ -0,0 +1,18 @@
+{-# LANGUAGE ScopedTypeVariables #-}
+
+module THEnv.JSON where
+
+import Data.Aeson (eitherDecode,FromJSON)
+import Data.ByteString.Lazy.Char8 (pack)
+import Language.Haskell.TH.Syntax (Exp,Lift(lift),Q)
+import THEnv (getCompileEnv)
+import Control.Monad
+
+getCompileEnvJSON :: (FromJSON a) => String -> Q a
+getCompileEnvJSON name =
+    either error (id :: a -> a) . eitherDecode . pack <$>  getCompileEnv name
+
+getCompileEnvJSONExp ::
+  forall proxy a. (FromJSON a, Lift a) => proxy a -> String -> Q Exp
+getCompileEnvJSONExp _ =
+    (lift :: a -> Q Exp) <=< getCompileEnvJSON

tv/5pkgs/haskell/xmonad-tv/src/main.hs

@@ -1,4 +1,6 @@
 {-# LANGUAGE LambdaCase #-}
+{-# LANGUAGE TemplateHaskell #-}
+{-# LANGUAGE TypeApplications #-}
 
 module Main (main) where
 
@@ -32,10 +34,23 @@ import XMonad.Stockholm.Pager
 import XMonad.Stockholm.Shutdown
 import qualified Paths
 
+import THEnv.JSON (getCompileEnvJSONExp)
+
 
 myFont :: String
 myFont = "-schumacher-*-*-*-*-*-*-*-*-*-*-*-iso10646-*"
 
+myScreenWidth :: Dimension
+myScreenWidth =
+  $(getCompileEnvJSONExp (id @Dimension) "XMONAD_BUILD_SCREEN_WIDTH")
+
+myTermFontWidth :: Dimension
+myTermFontWidth =
+  $(getCompileEnvJSONExp (id @Dimension) "XMONAD_BUILD_TERM_FONT_WIDTH")
+
+myTermPadding :: Dimension
+myTermPadding = 2
+
 
 main :: IO ()
 main = getArgs >>= \case
@@ -46,7 +61,6 @@ main = getArgs >>= \case
 
 mainNoArgs :: IO ()
 mainNoArgs = do
-    let width = 1366
     workspaces0 <- getWorkspaces0
     handleShutdownEvent <- newShutdownEventHandler
     launch
@@ -60,8 +74,9 @@ mainNoArgs = do
                 smartBorders $
                   ResizableTall
                     1
-                    (10 * 6 / width)
+                    (fromIntegral (10 * myTermFontWidth) / fromIntegral myScreenWidth)
-                    ((80 * 6 + 2 * (1+1+1))/width) []
+                    (fromIntegral (80 * myTermFontWidth + 2 * (myTermPadding + borderWidth def)) / fromIntegral myScreenWidth)
+                    []
                   |||
                   Full
             , manageHook =

tv/5pkgs/haskell/xmonad-tv/src/xmonad-tv.cabal

@@ -9,10 +9,14 @@ cabal-version: >=1.10
 executable xmonad
   main-is: main.hs
   build-depends:
+    aeson,
     base,
+    bytestring,
     containers,
     directory,
     extra,
+    template-haskell,
+    th-env,
     unix,
     X11,
     xmonad,
@@ -20,6 +24,7 @@ executable xmonad
     xmonad-stockholm
   other-modules:
     Helpers.Path,
-    Paths
+    Paths,
+    THEnv.JSON
   default-language: Haskell2010
   ghc-options: -O2 -Wall -threaded