update concentration.nix

common/concentration.nix

@@ -4,6 +4,21 @@
   config,
   ...
 }: {
+  options = {
+    blockYoutube = lib.mkOption {
+      type = lib.types.bool;
+      default = false;
+      description = "Disables youtube using /etc/hosts file";
+    };
+    blockTwitter = lib.mkOption {
+      type = lib.types.bool;
+      default = false;
+      description = "Disables twitter using /etc/hosts file";
+    };
+  };
+
+  config = lib.mkMerge [
+    (lib.mkIf config.blockYoutube {
       networking.extraHosts = ''
         0.0.0.0   youtube.com
         ::0       youtube.com
@@ -11,4 +26,15 @@
         0.0.0.0   www.youtube.com
         ::0       www.youtube.com
       '';
+    })
+    (lib.mkIf config.blockTwitter {
+      networking.extraHosts = ''
+        0.0.0.0   twitter.com
+        ::0       twitter.com
+
+        0.0.0.0   www.twitter.com
+        ::0       www.twitter.com
+      '';
+    })
+  ];
 }