feat: obsidian's vault helper command

hosts/desktop/shared-home.nix

@@ -38,7 +38,10 @@
     krita.enable = true;
     davinci.enable = true;
     obs.enable = true;
-    obsidian.enable = true;
+    obsidian = {
+      enable = true;
+      vaultCmd = true;
+    };
 
     librewolf = {
       enable = true;

modules/home-manager/programs/obsidian.nix

@@ -1,16 +1,43 @@
 { config, lib, pkgs, ... }:
 
+
 let
   cfg = config.obsidian;
+  vaultCmd = pkgs.writeShellScriptBin "vault" ''
+    command="$1";
+
+    if [[ "$command" == "sync" ]]; then
+      git="${pkgs.git}/bin/git";
+      date="$(date +%F) $(date +%R)"
+
+      cd ${cfg.vaultDir}
+      $git pull
+      if [[ "$(echo "$($git diff --shortstat)" | awk '{print $1}')" -ne "" ]]; then
+        $git commit -m "vault backup: $date" -a
+      fi
+      $git push
+    fi
+  '';
 in
 {
   imports = [ ];
   options.obsidian = with lib; with lib.types; {
     enable = mkEnableOption "";
+    vaultCmd = mkOption {
+      type = bool;
+      default = false;
+    };
+    vaultDir = mkOption {
+      type = str;
+      default = "${config.home.homeDirectory}/.vault";
+    };
   };
   config = lib.mkIf cfg.enable {
     services.flatpak.packages = [
       "md.obsidian.Obsidian"
     ];
+    home.packages = [
+      (if cfg.vaultCmd then vaultCmd else null)
+    ];
   };
 }