Cargo.lock

@@ -853,7 +853,7 @@ dependencies = [
 
 [[package]]
 name = "mould"
-version = "0.4.1"
+version = "0.4.2"
 dependencies = [
  "anyhow",
  "clap",

README.md

@@ -64,6 +64,7 @@ mould config.template.json -o config.json
   - `o`: Append a new item to the current array
   - `O`: Prepend a new item to the current array
   - `dd`: Delete the currently selected variable or group
+  - `u`: Undo the last change
   - `a`: Add missing value from template to active config
   - `/`: Search for configuration keys (Jump to matches)
   - `n`: Jump to the next search match

config.example.toml

@@ -44,3 +44,4 @@ jump_bottom = "G"
 append_item = "o"
 prepend_item = "O"
 delete_item = "dd"
+undo = "u"

src/app.rs

@@ -33,6 +33,8 @@ pub struct App {
     pub input: Input,
     /// The current search query for filtering keys.
     pub search_query: String,
+    /// Stack of previous variable states for undo functionality.
+    pub undo_stack: Vec<Vec<ConfigItem>>,
 }
 
 impl App {
@@ -47,6 +49,7 @@ impl App {
             status_message: None,
             input: Input::new(initial_input),
             search_query: String::new(),
+            undo_stack: Vec::new(),
         }
     }
 
@@ -159,8 +162,8 @@ impl App {
     pub fn enter_insert(&mut self, variant: InsertVariant) {
         if let Some(var) = self.vars.get(self.selected) {
             if !var.is_group {
+                self.save_undo_state();
                 self.mode = Mode::Insert;
-                self.status_message = None;
                 match variant {
                     InsertVariant::Start => {
                         use tui_input::InputRequest;
@@ -190,6 +193,7 @@ impl App {
             return;
         }
 
+        self.save_undo_state();
         let selected_path = self.vars[self.selected].path.clone();
         let is_group = self.vars[self.selected].is_group;
 
@@ -252,6 +256,7 @@ impl App {
             return;
         }
 
+        self.save_undo_state();
         let (base, idx, depth) = {
             let selected_item = &self.vars[self.selected];
             if selected_item.is_group {
@@ -322,6 +327,28 @@ impl App {
             .map(|v| v.status == crate::format::ItemStatus::MissingFromActive)
             .unwrap_or(false)
     }
+
+    /// Saves the current state of variables to the undo stack.
+    pub fn save_undo_state(&mut self) {
+        self.undo_stack.push(self.vars.clone());
+        if self.undo_stack.len() > 50 {
+            self.undo_stack.remove(0);
+        }
+    }
+
+    /// Reverts to the last saved state of variables.
+    pub fn undo(&mut self) {
+        if let Some(previous_vars) = self.undo_stack.pop() {
+            self.vars = previous_vars;
+            if self.selected >= self.vars.len() && !self.vars.is_empty() {
+                self.selected = self.vars.len() - 1;
+            }
+            self.sync_input_with_selected();
+            self.status_message = Some("Undo applied".to_string());
+        } else {
+            self.status_message = Some("Nothing to undo".to_string());
+        }
+    }
 }
 
 fn parse_index(path: &str) -> Option<(&str, usize)> {

src/config.rs

@@ -119,6 +119,7 @@ pub struct KeybindsConfig {
     pub append_item: String,
     pub prepend_item: String,
     pub delete_item: String,
+    pub undo: String,
 }
 
 impl Default for KeybindsConfig {
@@ -140,6 +141,7 @@ impl Default for KeybindsConfig {
             append_item: "o".to_string(),
             prepend_item: "O".to_string(),
             delete_item: "dd".to_string(),
+            undo: "u".to_string(),
         }
     }
 }

src/runner.rs

@@ -127,6 +127,7 @@ where
                 (&self.config.keybinds.append_item, "append_item"),
                 (&self.config.keybinds.prepend_item, "prepend_item"),
                 (&self.config.keybinds.delete_item, "delete_item"),
+                (&self.config.keybinds.undo, "undo"),
                 (&"a".to_string(), "add_missing"),
                 (&":".to_string(), "command"),
                 (&"q".to_string(), "quit"),
@@ -164,7 +165,11 @@ where
                     "append_item" => self.app.add_array_item(true),
                     "prepend_item" => self.app.add_array_item(false),
                     "delete_item" => self.app.delete_selected(),
-                    "add_missing" => self.add_missing_item(),
+                    "undo" => self.app.undo(),
+                    "add_missing" => {
+                        self.app.save_undo_state();
+                        self.add_missing_item();
+                    }
                     "command" => {
                         self.command_buffer.push(':');
                         self.sync_command_status();

src/ui.rs

@@ -272,21 +272,27 @@ pub fn draw(f: &mut Frame, app: &mut App, config: &Config) {
     let status_msg = if let Some(msg) = &app.status_message {
         msg.clone()
     } else {
+        let kb = &config.keybinds;
         match app.mode {
             Mode::Normal => {
-                let mut parts = vec!["j/k move", "gg/G jump", "/ search"];
+                let mut parts = vec![
+                    format!("{}/{} move", kb.down, kb.up),
+                    format!("{}/{} jump", kb.jump_top, kb.jump_bottom),
+                    format!("{} search", kb.search),
+                ];
                 if !app.selected_is_group() {
-                    parts.push("i/A/S edit");
+                    parts.push(format!("{}/{}/{} edit", kb.edit, kb.edit_append, kb.edit_substitute));
                 }
                 if app.selected_is_missing() {
-                    parts.push("a add");
+                    parts.push(format!("{} add", "a")); // 'a' is currently hardcoded in runner
                 }
                 if app.selected_is_array() {
-                    parts.push("o/O array");
+                    parts.push(format!("{}/{} array", kb.append_item, kb.prepend_item));
                 }
-                parts.push("dd del");
+                parts.push(format!("{} del", kb.delete_item));
-                parts.push(":w save");
+                parts.push(format!("{} undo", kb.undo));
-                parts.push(":q quit");
+                parts.push(format!("{} save", kb.save));
+                parts.push(format!("{} quit", kb.quit));
                 parts.join(" · ")
             }
             Mode::Insert => "Esc normal · Enter commit".to_string(),