chore(merge): branch 'main' into command-algebra

Add Claude Code GitHub Workflow

.github/workflows/claude-code-review.yml

@@ -0,0 +1,44 @@
+name: Claude Code Review
+
+on:
+  pull_request:
+    types: [opened, synchronize, ready_for_review, reopened]
+    # Optional: Only run on specific file changes
+    # paths:
+    #   - "src/**/*.ts"
+    #   - "src/**/*.tsx"
+    #   - "src/**/*.js"
+    #   - "src/**/*.jsx"
+
+jobs:
+  claude-review:
+    # Optional: Filter by PR author
+    # if: |
+    #   github.event.pull_request.user.login == 'external-contributor' ||
+    #   github.event.pull_request.user.login == 'new-developer' ||
+    #   github.event.pull_request.author_association == 'FIRST_TIME_CONTRIBUTOR'
+
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      pull-requests: read
+      issues: read
+      id-token: write
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 1
+
+      - name: Run Claude Code Review
+        id: claude-review
+        uses: anthropics/claude-code-action@v1
+        with:
+          claude_code_oauth_token: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
+          plugin_marketplaces: 'https://github.com/anthropics/claude-code.git'
+          plugins: 'code-review@claude-code-plugins'
+          prompt: '/code-review:code-review ${{ github.repository }}/pull/${{ github.event.pull_request.number }}'
+          # See https://github.com/anthropics/claude-code-action/blob/main/docs/usage.md
+          # or https://code.claude.com/docs/en/cli-reference for available options
+

.github/workflows/claude.yml

@@ -0,0 +1,50 @@
+name: Claude Code
+
+on:
+  issue_comment:
+    types: [created]
+  pull_request_review_comment:
+    types: [created]
+  issues:
+    types: [opened, assigned]
+  pull_request_review:
+    types: [submitted]
+
+jobs:
+  claude:
+    if: |
+      (github.event_name == 'issue_comment' && contains(github.event.comment.body, '@claude')) ||
+      (github.event_name == 'pull_request_review_comment' && contains(github.event.comment.body, '@claude')) ||
+      (github.event_name == 'pull_request_review' && contains(github.event.review.body, '@claude')) ||
+      (github.event_name == 'issues' && (contains(github.event.issue.body, '@claude') || contains(github.event.issue.title, '@claude')))
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      pull-requests: read
+      issues: read
+      id-token: write
+      actions: read # Required for Claude to read CI results on PRs
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 1
+
+      - name: Run Claude Code
+        id: claude
+        uses: anthropics/claude-code-action@v1
+        with:
+          claude_code_oauth_token: ${{ secrets.CLAUDE_CODE_OAUTH_TOKEN }}
+
+          # This is an optional setting that allows Claude to read CI results on PRs
+          additional_permissions: |
+            actions: read
+
+          # Optional: Give a custom prompt to Claude. If this is not specified, Claude will perform the instructions specified in the comment that tagged it.
+          # prompt: 'Update the pull request description to include a summary of changes.'
+
+          # Optional: Add claude_args to customize behavior and configuration
+          # See https://github.com/anthropics/claude-code-action/blob/main/docs/usage.md
+          # or https://code.claude.com/docs/en/cli-reference for available options
+          # claude_args: '--allowed-tools Bash(gh pr:*)'
+

.gitignore

@@ -8,3 +8,7 @@ symbols.json
 profile.json
 profile.json.gz
 bench/*.txt
+
+# Added by git-smart-commit
+*.patch
+*.improv

src/command/keymap.rs

@@ -72,6 +72,8 @@ pub enum Binding {
     },
     /// A prefix sub-keymap (Emacs-style).
     Prefix(Arc<Keymap>),
+    /// A sequence of commands executed in order, concatenating their effects.
+    Sequence(Vec<(&'static str, Vec<String>)>),
 }
 
 /// A keymap maps key patterns to bindings (command names or prefix sub-keymaps).
@@ -121,6 +123,17 @@ impl Keymap {
             .insert(KeyPattern::Key(key, mods), Binding::Prefix(sub));
     }
 
+    /// Bind a key to a sequence of commands (executed in order).
+    pub fn bind_seq(
+        &mut self,
+        key: KeyCode,
+        mods: KeyModifiers,
+        steps: Vec<(&'static str, Vec<String>)>,
+    ) {
+        self.bindings
+            .insert(KeyPattern::Key(key, mods), Binding::Sequence(steps));
+    }
+
     /// Bind a catch-all for any Char key.
     pub fn bind_any_char(&mut self, name: &'static str, args: Vec<String>) {
         self.bindings
@@ -143,8 +156,7 @@ impl Keymap {
             .or_else(|| {
                 // Retry Char keys without modifiers (shift is implicit in the char)
                 if matches!(key, KeyCode::Char(_)) && mods != KeyModifiers::NONE {
-                    self.bindings
-                        .get(&KeyPattern::Key(key, KeyModifiers::NONE))
+                    self.bindings.get(&KeyPattern::Key(key, KeyModifiers::NONE))
                 } else {
                     None
                 }
@@ -174,6 +186,14 @@ impl Keymap {
                 Some(cmd.execute(ctx))
             }
             Binding::Prefix(sub) => Some(vec![Box::new(SetTransientKeymap(sub.clone()))]),
+            Binding::Sequence(steps) => {
+                let mut effects: Vec<Box<dyn Effect>> = Vec::new();
+                for (name, args) in steps {
+                    let cmd = registry.interactive(name, args, ctx).ok()?;
+                    effects.extend(cmd.execute(ctx));
+                }
+                Some(effects)
+            }
         }
     }
 }
@@ -266,10 +286,14 @@ impl KeymapSet {
         normal.bind(KeyCode::Char('G'), none, "jump-last-row");
         normal.bind(KeyCode::Char('0'), none, "jump-first-col");
         normal.bind(KeyCode::Char('$'), none, "jump-last-col");
+        normal.bind(KeyCode::Home, none, "jump-first-col");
+        normal.bind(KeyCode::End, none, "jump-last-col");
 
         // Scroll
         normal.bind_args(KeyCode::Char('d'), ctrl, "scroll-rows", vec!["5".into()]);
         normal.bind_args(KeyCode::Char('u'), ctrl, "scroll-rows", vec!["-5".into()]);
+        normal.bind_args(KeyCode::PageDown, none, "page-scroll", vec!["1".into()]);
+        normal.bind_args(KeyCode::PageUp, none, "page-scroll", vec!["-1".into()]);
 
         // Cell operations
         normal.bind(KeyCode::Char('x'), none, "clear-cell");
@@ -357,7 +381,11 @@ impl KeymapSet {
         // Drill into aggregated cell / view history / add row
         normal.bind(KeyCode::Char('>'), none, "drill-into-cell");
         normal.bind(KeyCode::Char('<'), none, "view-back");
-        normal.bind(KeyCode::Char('o'), none, "add-record-row");
+        normal.bind_seq(
+            KeyCode::Char('o'),
+            none,
+            vec![("add-record-row", vec![]), ("enter-edit-at-cursor", vec![])],
+        );
 
         // Records mode toggle and prune toggle
         normal.bind(KeyCode::Char('R'), none, "toggle-records-mode");
@@ -381,7 +409,11 @@ impl KeymapSet {
         normal.bind_prefix(KeyCode::Char('y'), none, Arc::new(y_map));
 
         let mut z_map = Keymap::new();
-        z_map.bind(KeyCode::Char('Z'), none, "save-and-quit");
+        z_map.bind_seq(
+            KeyCode::Char('Z'),
+            none,
+            vec![("save", vec![]), ("force-quit", vec![])],
+        );
         normal.bind_prefix(KeyCode::Char('Z'), none, Arc::new(z_map));
 
         set.insert(ModeKey::Normal, Arc::new(normal));
@@ -422,9 +454,24 @@ impl KeymapSet {
         fp.bind(KeyCode::Char('o'), none, "enter-formula-edit");
         fp.bind(KeyCode::Char('d'), none, "delete-formula-at-cursor");
         fp.bind(KeyCode::Delete, none, "delete-formula-at-cursor");
-        fp.bind_args(KeyCode::Char('F'), none, "toggle-panel-and-focus", vec!["formula".into()]);
-        fp.bind_args(KeyCode::Char('C'), none, "toggle-panel-and-focus", vec!["category".into()]);
-        fp.bind_args(KeyCode::Char('V'), none, "toggle-panel-and-focus", vec!["view".into()]);
+        fp.bind_args(
+            KeyCode::Char('F'),
+            none,
+            "toggle-panel-and-focus",
+            vec!["formula".into()],
+        );
+        fp.bind_args(
+            KeyCode::Char('C'),
+            none,
+            "toggle-panel-and-focus",
+            vec!["category".into()],
+        );
+        fp.bind_args(
+            KeyCode::Char('V'),
+            none,
+            "toggle-panel-and-focus",
+            vec!["view".into()],
+        );
         set.insert(ModeKey::FormulaPanel, Arc::new(fp));
 
         // ── Category panel ───────────────────────────────────────────────
@@ -505,9 +552,24 @@ impl KeymapSet {
         vp.bind(KeyCode::Char('o'), none, "create-and-switch-view");
         vp.bind(KeyCode::Char('d'), none, "delete-view-at-cursor");
         vp.bind(KeyCode::Delete, none, "delete-view-at-cursor");
-        vp.bind_args(KeyCode::Char('V'), none, "toggle-panel-and-focus", vec!["view".into()]);
-        vp.bind_args(KeyCode::Char('C'), none, "toggle-panel-and-focus", vec!["category".into()]);
-        vp.bind_args(KeyCode::Char('F'), none, "toggle-panel-and-focus", vec!["formula".into()]);
+        vp.bind_args(
+            KeyCode::Char('V'),
+            none,
+            "toggle-panel-and-focus",
+            vec!["view".into()],
+        );
+        vp.bind_args(
+            KeyCode::Char('C'),
+            none,
+            "toggle-panel-and-focus",
+            vec!["category".into()],
+        );
+        vp.bind_args(
+            KeyCode::Char('F'),
+            none,
+            "toggle-panel-and-focus",
+            vec!["formula".into()],
+        );
         set.insert(ModeKey::ViewPanel, Arc::new(vp));
 
         // ── Tile select ──────────────────────────────────────────────────
@@ -560,6 +622,7 @@ impl KeymapSet {
         let mut ed = Keymap::new();
         ed.bind_args(KeyCode::Esc, none, "enter-mode", vec!["normal".into()]);
         ed.bind(KeyCode::Enter, none, "commit-cell-edit");
+        ed.bind(KeyCode::Tab, none, "commit-and-advance-right");
         ed.bind_args(KeyCode::Backspace, none, "pop-char", vec!["edit".into()]);
         ed.bind_any_char("append-char", vec!["edit".into()]);
         set.insert(ModeKey::Editing, Arc::new(ed));
@@ -630,8 +693,8 @@ impl KeymapSet {
         let mut sm = Keymap::new();
         sm.bind(KeyCode::Esc, none, "exit-search-mode");
         sm.bind(KeyCode::Enter, none, "exit-search-mode");
-        sm.bind(KeyCode::Backspace, none, "search-pop-char");
-        sm.bind_any_char("search-append-char", vec![]);
+        sm.bind_args(KeyCode::Backspace, none, "pop-char", vec!["search".into()]);
+        sm.bind_any_char("append-char", vec!["search".into()]);
         set.insert(ModeKey::SearchMode, Arc::new(sm));
 
         // ── Import wizard ────────────────────────────────────────────────

src/draw.rs

@@ -257,6 +257,7 @@ fn draw_content(f: &mut Frame, area: Rect, app: &App) {
     f.render_widget(
         GridWidget::new(
             &app.model,
+            &app.layout,
             &app.mode,
             &app.search_query,
             &app.buffers,
@@ -282,11 +283,7 @@ fn draw_bottom_bar(f: &mut Frame, area: Rect, app: &App) {
             Some((format!("edit: {buf}▌"), Color::Green))
         }
         AppMode::FormulaEdit { .. } => {
-            let buf = app
-                .buffers
-                .get("formula")
-                .map(|s| s.as_str())
-                .unwrap_or("");
+            let buf = app.buffers.get("formula").map(|s| s.as_str()).unwrap_or("");
             Some((format!("formula: {buf}▌"), Color::Cyan))
         }
         AppMode::CategoryAdd { .. } => {
@@ -302,11 +299,7 @@ fn draw_bottom_bar(f: &mut Frame, area: Rect, app: &App) {
             Some((format!("add item to {category}: {buf}▌"), Color::Green))
         }
         AppMode::ExportPrompt { .. } => {
-            let buf = app
-                .buffers
-                .get("export")
-                .map(|s| s.as_str())
-                .unwrap_or("");
+            let buf = app.buffers.get("export").map(|s| s.as_str()).unwrap_or("");
             Some((format!("export path: {buf}▌"), Color::Yellow))
         }
         _ => None,
@@ -349,7 +342,6 @@ fn draw_status(f: &mut Frame, area: Rect, app: &App) {
     f.render_widget(Paragraph::new(line).style(mode_style(&app.mode)), area);
 }
 
-
 fn draw_welcome(f: &mut Frame, area: Rect) {
     let popup = centered_popup(area, 58, 20);
     let inner = draw_popup_frame(f, popup, "  Welcome to improvise  ", Color::Blue);

src/format.rs

@@ -0,0 +1,50 @@
+use crate::model::cell::CellValue;
+
+/// Format a CellValue for display with number formatting options.
+pub fn format_value(v: Option<&CellValue>, comma: bool, decimals: u8) -> String {
+    match v {
+        Some(CellValue::Number(n)) => format_f64(*n, comma, decimals),
+        Some(CellValue::Text(s)) => s.clone(),
+        None => String::new(),
+    }
+}
+
+/// Parse a number format string like ",.0" into (use_commas, decimal_places).
+pub fn parse_number_format(fmt: &str) -> (bool, u8) {
+    let comma = fmt.contains(',');
+    let decimals = fmt
+        .rfind('.')
+        .and_then(|i| fmt[i + 1..].parse::<u8>().ok())
+        .unwrap_or(0);
+    (comma, decimals)
+}
+
+/// Format an f64 with optional comma grouping and decimal places.
+pub fn format_f64(n: f64, comma: bool, decimals: u8) -> String {
+    let formatted = format!("{:.prec$}", n, prec = decimals as usize);
+    if !comma {
+        return formatted;
+    }
+    let (int_part, dec_part) = if let Some(dot) = formatted.find('.') {
+        (&formatted[..dot], Some(&formatted[dot..]))
+    } else {
+        (&formatted[..], None)
+    };
+    let is_neg = int_part.starts_with('-');
+    let digits = if is_neg { &int_part[1..] } else { int_part };
+    let mut result = String::new();
+    for (idx, c) in digits.chars().rev().enumerate() {
+        if idx > 0 && idx % 3 == 0 {
+            result.push(',');
+        }
+        result.push(c);
+    }
+    if is_neg {
+        result.push('-');
+    }
+    let mut out: String = result.chars().rev().collect();
+    if let Some(dec) = dec_part {
+        out.push_str(dec);
+    }
+    out
+}

src/main.rs

@@ -1,5 +1,6 @@
 mod command;
 mod draw;
+mod format;
 mod formula;
 mod import;
 mod model;

src/model/cell.rs

@@ -93,7 +93,6 @@ impl std::fmt::Display for CellValue {
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
 pub struct InternedKey(pub Vec<(Symbol, Symbol)>);
 
-
 /// Serialized as a list of (key, value) pairs so CellKey doesn't need
 /// to implement the `Serialize`-as-string requirement for JSON object keys.
 #[derive(Debug, Clone, Default)]
@@ -180,9 +179,7 @@ impl DataStore {
 
     /// Iterate over all cells, yielding (CellKey, &CellValue) pairs.
     pub fn iter_cells(&self) -> impl Iterator<Item = (CellKey, &CellValue)> {
-        self.cells
-            .iter()
-            .map(|(k, v)| (self.to_cell_key(k), v))
+        self.cells.iter().map(|(k, v)| (self.to_cell_key(k), v))
     }
 
     pub fn remove(&mut self, key: &CellKey) {

src/model/types.rs

@@ -132,8 +132,7 @@ impl Model {
             self.data.remove(&k);
         }
         // Remove formulas targeting this category
-        self.formulas
-            .retain(|f| f.target_category != name);
+        self.formulas.retain(|f| f.target_category != name);
     }
 
     /// Remove an item from a category and all cells that reference it.

src/persistence/mod.rs

@@ -458,17 +458,7 @@ pub fn export_csv(model: &Model, view_name: &str, path: &Path) -> Result<()> {
             out.push(',');
         }
         let row_values: Vec<String> = (0..layout.col_count())
-            .map(|ci| {
-                if layout.is_records_mode() {
-                    layout.records_display(ri, ci).unwrap_or_default()
-                } else {
-                    layout
-                        .cell_key(ri, ci)
-                        .and_then(|key| model.evaluate_aggregated(&key, &layout.none_cats))
-                        .map(|v| v.to_string())
-                        .unwrap_or_default()
-                }
-            })
+            .map(|ci| layout.display_text(model, ri, ci, false, 0))
             .collect();
         out.push_str(&row_values.join(","));
         out.push('\n');

src/ui/app.rs

@@ -5,23 +5,25 @@ use std::path::PathBuf;
 use std::sync::Arc;
 use std::time::{Duration, Instant};
 
+use std::rc::Rc;
+
 use crate::command::cmd::CmdContext;
 use crate::command::keymap::{Keymap, KeymapSet};
 use crate::import::wizard::ImportWizard;
 use crate::model::cell::CellValue;
 use crate::model::Model;
 use crate::persistence;
+use crate::ui::grid::{
+    compute_col_widths, compute_row_header_width, compute_visible_cols, parse_number_format,
+};
 use crate::view::GridLayout;
 
 /// Drill-down state: frozen record snapshot + pending edits that have not
 /// yet been applied to the model.
 #[derive(Debug, Clone, Default)]
 pub struct DrillState {
-    /// Frozen snapshot of records shown in the drill view.
-    pub records: Vec<(
-        crate::model::cell::CellKey,
-        crate::model::cell::CellValue,
-    )>,
+    /// Frozen snapshot of records shown in the drill view (Rc for cheap cloning).
+    pub records: Rc<Vec<(crate::model::cell::CellKey, crate::model::cell::CellValue)>>,
     /// Pending edits keyed by (record_idx, column_name) → new string value.
     /// column_name is either "Value" or a category name.
     pub pending_edits: std::collections::HashMap<(usize, String), String>,
@@ -100,11 +102,18 @@ pub struct App {
     pub buffers: HashMap<String, String>,
     /// Transient keymap for Emacs-style prefix key sequences (g→gg, y→yy, etc.)
     pub transient_keymap: Option<Arc<Keymap>>,
+    /// Current grid layout, derived from model + view + drill_state.
+    /// Rebuilt via `rebuild_layout()` after state changes.
+    pub layout: GridLayout,
     keymap_set: KeymapSet,
 }
 
 impl App {
     pub fn new(model: Model, file_path: Option<PathBuf>) -> Self {
+        let layout = {
+            let view = model.active_view();
+            GridLayout::with_frozen_records(&model, view, None)
+        };
         Self {
             model,
             file_path,
@@ -131,17 +140,26 @@ impl App {
             expanded_cats: std::collections::HashSet::new(),
             buffers: HashMap::new(),
             transient_keymap: None,
+            layout,
             keymap_set: KeymapSet::default_keymaps(),
         }
     }
 
+    /// Rebuild the grid layout from current model, view, and drill state.
+    /// Note: `with_frozen_records` already handles pruning internally.
+    pub fn rebuild_layout(&mut self) {
+        let view = self.model.active_view();
+        let frozen = self.drill_state.as_ref().map(|s| Rc::clone(&s.records));
+        self.layout = GridLayout::with_frozen_records(&self.model, view, frozen);
+    }
+
     pub fn cmd_context(&self, key: KeyCode, _mods: KeyModifiers) -> CmdContext<'_> {
         let view = self.model.active_view();
-        let frozen_records = self.drill_state.as_ref().map(|s| s.records.clone());
-        let layout = GridLayout::with_frozen_records(&self.model, view, frozen_records);
+        let layout = &self.layout;
         let (sel_row, sel_col) = view.selected;
         CmdContext {
             model: &self.model,
+            layout,
             mode: &self.mode,
             selected: view.selected,
             row_offset: view.row_offset,
@@ -158,34 +176,39 @@ impl App {
             cat_panel_cursor: self.cat_panel_cursor,
             view_panel_cursor: self.view_panel_cursor,
             tile_cat_idx: self.tile_cat_idx,
-            cell_key: layout.cell_key(sel_row, sel_col),
-            row_count: layout.row_count(),
-            col_count: layout.col_count(),
-            none_cats: layout.none_cats.clone(),
-            view_back_stack: self.view_back_stack.clone(),
-            view_forward_stack: self.view_forward_stack.clone(),
-            records_col: if layout.is_records_mode() {
-                Some(layout.col_label(sel_col))
+            view_back_stack: &self.view_back_stack,
+            view_forward_stack: &self.view_forward_stack,
+            display_value: {
+                let key = layout.cell_key(sel_row, sel_col);
+                if let Some(k) = &key {
+                    if let Some((idx, dim)) = crate::view::synthetic_record_info(k) {
+                        self.drill_state
+                            .as_ref()
+                            .and_then(|s| s.pending_edits.get(&(idx, dim)).cloned())
+                            .or_else(|| layout.resolve_display(k))
+                            .unwrap_or_default()
                     } else {
-                None
-            },
-            records_value: if layout.is_records_mode() {
-                // Check pending edits first, then fall back to original
-                let col_name = layout.col_label(sel_col);
-                let pending = self.drill_state.as_ref().and_then(|s| {
-                    s.pending_edits.get(&(sel_row, col_name.clone())).cloned()
-                });
-                pending.or_else(|| layout.records_display(sel_row, sel_col))
+                        self.model
+                            .get_cell(k)
+                            .map(|v| v.to_string())
+                            .unwrap_or_default()
+                    }
                 } else {
-                None
+                    String::new()
+                }
             },
-            // Approximate visible rows/cols from terminal size.
-            // Chrome: title(1) + border(2) + col_headers(n_col_levels) + separator(1)
-            //         + tile_bar(1) + status_bar(1) = ~8 rows of chrome.
             visible_rows: (self.term_height as usize).saturating_sub(8),
-            // Visible cols depends on column widths — use a rough estimate.
-            // The grid renderer does the precise calculation.
-            visible_cols: ((self.term_width as usize).saturating_sub(30) / 12).max(1),
+            visible_cols: {
+                let (fmt_comma, fmt_decimals) = parse_number_format(&view.number_format);
+                let col_widths = compute_col_widths(&self.model, layout, fmt_comma, fmt_decimals);
+                let row_header_width = compute_row_header_width(layout);
+                compute_visible_cols(
+                    &col_widths,
+                    row_header_width,
+                    self.term_width,
+                    view.col_offset,
+                )
+            },
             expanded_cats: &self.expanded_cats,
             key_code: key,
         }
@@ -195,6 +218,7 @@ impl App {
         for effect in effects {
             effect.apply(self);
         }
+        self.rebuild_layout();
     }
 
     /// True when the model has no categories yet (show welcome screen)
@@ -203,6 +227,8 @@ impl App {
     }
 
     pub fn handle_key(&mut self, key: KeyEvent) -> Result<()> {
+        self.rebuild_layout();
+
         // Transient keymap (prefix key sequence) takes priority
         if let Some(transient) = self.transient_keymap.take() {
             let effects = {
@@ -247,7 +273,7 @@ impl App {
     pub fn hint_text(&self) -> &'static str {
         match &self.mode {
             AppMode::Normal => "hjkl:nav  i:edit  R:records  P:prune  F/C/V:panels  T:tiles  [:]:page  >:drill  ::cmd",
-            AppMode::Editing { .. } => "Enter:commit  Esc:cancel",
+            AppMode::Editing { .. } => "Enter:commit  Tab:commit+right  Esc:cancel",
             AppMode::FormulaPanel => "n:new  d:delete  jk:nav  Esc:back",
             AppMode::FormulaEdit { .. } => "Enter:save  Esc:cancel  — type: Name = expression",
             AppMode::CategoryPanel => "jk:nav  Space:cycle-axis  n:new-cat  a:add-items  d:delete  Esc:back",
@@ -371,6 +397,190 @@ mod tests {
         assert_eq!(app.buffers.get("command").map(|s| s.as_str()), Some("q"));
     }
 
+    #[test]
+    fn col_offset_scrolls_when_cursor_moves_past_visible_columns() {
+        use crate::model::cell::{CellKey, CellValue};
+        // Create a model with 8 wide columns. Column item names are 30 chars
+        // each → column widths ~31 chars. With term_width=80, row header ~4,
+        // data area ~76 → only ~2 columns actually fit. But the rough estimate
+        // (80−30)/12 = 4 over-counts, so viewport_effects never scrolls.
+        let mut m = Model::new("T");
+        m.add_category("Row").unwrap();
+        m.add_category("Col").unwrap();
+        m.category_mut("Row").unwrap().add_item("R1");
+        for i in 0..8 {
+            let name = format!("VeryLongColumnItemName_{i:03}");
+            m.category_mut("Col").unwrap().add_item(&name);
+        }
+        // Populate a value so the model isn't empty
+        let key = CellKey::new(vec![
+            ("Row".to_string(), "R1".to_string()),
+            ("Col".to_string(), "VeryLongColumnItemName_000".to_string()),
+        ]);
+        m.set_cell(key, CellValue::Number(1.0));
+
+        let mut app = App::new(m, None);
+        app.term_width = 80;
+
+        // Press 'l' (right) 3 times to move cursor to column 3.
+        // Only ~2 columns fit in 76 chars of data area (each col ~26 chars wide),
+        // so column 3 is well off-screen. The buggy estimate (80−30)/12 = 4
+        // thinks 4 columns fit, so it won't scroll until col 4.
+        for _ in 0..3 {
+            app.handle_key(KeyEvent::new(KeyCode::Char('l'), KeyModifiers::NONE))
+                .unwrap();
+        }
+
+        assert_eq!(
+            app.model.active_view().selected.1,
+            3,
+            "cursor should be at column 3"
+        );
+        assert!(
+            app.model.active_view().col_offset > 0,
+            "col_offset should scroll when cursor moves past visible area (only ~2 cols fit \
+             in 80-char terminal with 26-char-wide columns), but col_offset is {}",
+            app.model.active_view().col_offset
+        );
+    }
+
+    #[test]
+    fn home_jumps_to_first_col() {
+        let mut app = two_col_model();
+        app.model.active_view_mut().selected = (1, 1);
+        app.handle_key(KeyEvent::new(KeyCode::Home, KeyModifiers::NONE))
+            .unwrap();
+        assert_eq!(app.model.active_view().selected, (1, 0));
+    }
+
+    #[test]
+    fn end_jumps_to_last_col() {
+        let mut app = two_col_model();
+        app.model.active_view_mut().selected = (1, 0);
+        app.handle_key(KeyEvent::new(KeyCode::End, KeyModifiers::NONE))
+            .unwrap();
+        assert_eq!(app.model.active_view().selected, (1, 1));
+    }
+
+    #[test]
+    fn page_down_scrolls_by_three_quarters_visible() {
+        let mut app = two_col_model();
+        // Add enough rows
+        for i in 0..30 {
+            app.model
+                .category_mut("Row")
+                .unwrap()
+                .add_item(&format!("R{i}"));
+        }
+        app.term_height = 28; // ~20 visible rows → delta = 15
+        app.model.active_view_mut().selected = (0, 0);
+        app.handle_key(KeyEvent::new(KeyCode::PageDown, KeyModifiers::NONE))
+            .unwrap();
+        assert_eq!(app.model.active_view().selected.1, 0, "column preserved");
+        assert!(
+            app.model.active_view().selected.0 > 0,
+            "row should advance on PageDown"
+        );
+        // 3/4 of ~20 = 15
+        assert_eq!(app.model.active_view().selected.0, 15);
+    }
+
+    #[test]
+    fn page_up_scrolls_backward() {
+        let mut app = two_col_model();
+        for i in 0..30 {
+            app.model
+                .category_mut("Row")
+                .unwrap()
+                .add_item(&format!("R{i}"));
+        }
+        app.term_height = 28;
+        app.model.active_view_mut().selected = (20, 0);
+        app.handle_key(KeyEvent::new(KeyCode::PageUp, KeyModifiers::NONE))
+            .unwrap();
+        assert_eq!(app.model.active_view().selected.0, 5);
+    }
+
+    #[test]
+    fn jump_last_row_scrolls_with_small_terminal() {
+        let mut app = two_col_model();
+        // Total rows: A, B, C + R0..R9 = 13 rows. Last row = 12.
+        for i in 0..10 {
+            app.model
+                .category_mut("Row")
+                .unwrap()
+                .add_item(&format!("R{i}"));
+        }
+        app.term_height = 13; // ~5 visible rows
+        app.model.active_view_mut().selected = (0, 0);
+        // G jumps to last row (row 12)
+        app.handle_key(KeyEvent::new(KeyCode::Char('G'), KeyModifiers::NONE))
+            .unwrap();
+        let last = app.model.active_view().selected.0;
+        assert_eq!(last, 12, "should be at last row");
+        // With only ~5 visible rows and 13 rows, offset should scroll.
+        // Bug: hardcoded 20 means `12 >= 0 + 20` is false → no scroll.
+        let offset = app.model.active_view().row_offset;
+        assert!(
+            offset > 0,
+            "row_offset should scroll when last row is beyond visible area, but is {offset}"
+        );
+    }
+
+    #[test]
+    fn ctrl_d_scrolls_viewport_with_small_terminal() {
+        let mut app = two_col_model();
+        for i in 0..30 {
+            app.model
+                .category_mut("Row")
+                .unwrap()
+                .add_item(&format!("R{i}"));
+        }
+        app.term_height = 13; // ~5 visible rows
+        app.model.active_view_mut().selected = (0, 0);
+        // Ctrl+d scrolls by 5 rows
+        app.handle_key(KeyEvent::new(KeyCode::Char('d'), KeyModifiers::CONTROL))
+            .unwrap();
+        assert_eq!(app.model.active_view().selected.0, 5);
+        // Press Ctrl+d again — now at row 10 with only 5 visible rows,
+        // row_offset should have scrolled (not stay at 0 due to hardcoded 20)
+        app.handle_key(KeyEvent::new(KeyCode::Char('d'), KeyModifiers::CONTROL))
+            .unwrap();
+        assert_eq!(app.model.active_view().selected.0, 10);
+        assert!(
+            app.model.active_view().row_offset > 0,
+            "row_offset should scroll with small terminal, but is {}",
+            app.model.active_view().row_offset
+        );
+    }
+
+    #[test]
+    fn tab_in_edit_mode_commits_and_moves_right() {
+        let mut app = two_col_model();
+        app.model.active_view_mut().selected = (0, 0);
+        // Enter edit mode
+        app.handle_key(KeyEvent::new(KeyCode::Char('i'), KeyModifiers::NONE))
+            .unwrap();
+        assert!(matches!(app.mode, AppMode::Editing { .. }));
+        // Type a digit
+        app.handle_key(KeyEvent::new(KeyCode::Char('5'), KeyModifiers::NONE))
+            .unwrap();
+        // Press Tab — should commit, move right, re-enter edit mode
+        app.handle_key(KeyEvent::new(KeyCode::Tab, KeyModifiers::NONE))
+            .unwrap();
+        // Should be in edit mode on column 1
+        assert!(
+            matches!(app.mode, AppMode::Editing { .. }),
+            "should be in edit mode after Tab, but mode is {:?}",
+            app.mode
+        );
+        assert_eq!(
+            app.model.active_view().selected.1,
+            1,
+            "should have moved to column 1"
+        );
+    }
+
     #[test]
     fn command_mode_buffer_cleared_on_reentry() {
         use crossterm::event::KeyEvent;

src/ui/category_panel.rs

@@ -49,7 +49,7 @@ impl<'a> Widget for CategoryPanel<'a> {
         let is_active = matches!(self.mode, AppMode::CategoryPanel) || is_item_add || is_cat_add;
 
         let (border_color, title) = if is_active {
-            (Color::Cyan, " Categories  n:new  d:del  Space:axis ")
+            (Color::Cyan, " Categories ")
         } else {
             (Color::DarkGray, " Categories ")
         };

src/ui/effect.rs

@@ -96,16 +96,12 @@ impl Effect for RemoveFormula {
 pub struct EnterEditAtCursor;
 impl Effect for EnterEditAtCursor {
     fn apply(&self, app: &mut App) {
-        let ctx = app.cmd_context(crossterm::event::KeyCode::Null, crossterm::event::KeyModifiers::NONE);
-        let value = if let Some(v) = &ctx.records_value {
-            v.clone()
-        } else {
-            ctx.cell_key
-                .as_ref()
-                .and_then(|k| ctx.model.get_cell(k).cloned())
-                .map(|v| v.to_string())
-                .unwrap_or_default()
-        };
+        app.rebuild_layout();
+        let ctx = app.cmd_context(
+            crossterm::event::KeyCode::Null,
+            crossterm::event::KeyModifiers::NONE,
+        );
+        let value = ctx.display_value.clone();
         drop(ctx);
         app.buffers.insert("edit".to_string(), value);
         app.mode = AppMode::Editing {
@@ -406,7 +402,7 @@ pub struct StartDrill(pub Vec<(CellKey, CellValue)>);
 impl Effect for StartDrill {
     fn apply(&self, app: &mut App) {
         app.drill_state = Some(super::app::DrillState {
-            records: self.0.clone(),
+            records: std::rc::Rc::new(self.0.clone()),
             pending_edits: std::collections::HashMap::new(),
         });
     }
@@ -480,9 +476,10 @@ pub struct SetDrillPendingEdit {
 impl Effect for SetDrillPendingEdit {
     fn apply(&self, app: &mut App) {
         if let Some(drill) = &mut app.drill_state {
-            drill
-                .pending_edits
-                .insert((self.record_idx, self.col_name.clone()), self.new_value.clone());
+            drill.pending_edits.insert(
+                (self.record_idx, self.col_name.clone()),
+                self.new_value.clone(),
+            );
         }
     }
 }
@@ -838,6 +835,16 @@ pub enum Panel {
     View,
 }
 
+impl Panel {
+    pub fn mode(self) -> AppMode {
+        match self {
+            Panel::Formula => AppMode::FormulaPanel,
+            Panel::Category => AppMode::CategoryPanel,
+            Panel::View => AppMode::ViewPanel,
+        }
+    }
+}
+
 impl Effect for SetPanelOpen {
     fn apply(&self, app: &mut App) {
         match self.panel {

src/ui/grid.rs

@@ -6,7 +6,6 @@ use ratatui::{
 };
 use unicode_width::UnicodeWidthStr;
 
-use crate::model::cell::CellValue;
 use crate::model::Model;
 use crate::ui::app::AppMode;
 use crate::view::{AxisEntry, GridLayout};
@@ -23,6 +22,7 @@ const GROUP_COLLAPSED: &str = "▶";
 
 pub struct GridWidget<'a> {
     pub model: &'a Model,
+    pub layout: &'a GridLayout,
     pub mode: &'a AppMode,
     pub search_query: &'a str,
     pub buffers: &'a std::collections::HashMap<String, String>,
@@ -32,6 +32,7 @@ pub struct GridWidget<'a> {
 impl<'a> GridWidget<'a> {
     pub fn new(
         model: &'a Model,
+        layout: &'a GridLayout,
         mode: &'a AppMode,
         search_query: &'a str,
         buffers: &'a std::collections::HashMap<String, String>,
@@ -39,6 +40,7 @@ impl<'a> GridWidget<'a> {
     ) -> Self {
         Self {
             model,
+            layout,
             mode,
             search_query,
             buffers,
@@ -46,23 +48,9 @@ impl<'a> GridWidget<'a> {
         }
     }
 
-    /// In records mode, get the display text for (row, col): pending edit if
-    /// staged, otherwise the underlying record's value for that column.
-    fn records_cell_text(&self, layout: &GridLayout, row: usize, col: usize) -> String {
-        let col_name = layout.col_label(col);
-        let pending = self
-            .drill_state
-            .and_then(|s| s.pending_edits.get(&(row, col_name.clone())).cloned());
-        pending
-            .or_else(|| layout.records_display(row, col))
-            .unwrap_or_default()
-    }
-
     fn render_grid(&self, area: Rect, buf: &mut Buffer) {
         let view = self.model.active_view();
-
-        let frozen = self.drill_state.map(|s| s.records.clone());
-        let layout = GridLayout::with_frozen_records(self.model, view, frozen);
+        let layout = self.layout;
         let (sel_row, sel_col) = view.selected;
         let row_offset = view.row_offset;
         let col_offset = view.col_offset;
@@ -71,56 +59,9 @@ impl<'a> GridWidget<'a> {
         let n_col_levels = layout.col_cats.len().max(1);
         let n_row_levels = layout.row_cats.len().max(1);
 
-        // ── Adaptive column widths ────────────────────────────────────
-        // Size each column to fit its widest content (header + cell values)
-        // plus 1 char gap. Minimum MIN_COL_WIDTH, capped at MAX_COL_WIDTH.
-        let col_widths: Vec<u16> = {
-            let n = layout.col_count();
-            let mut widths = vec![0u16; n];
-            // Measure column header labels
-            for ci in 0..n {
-                let header = layout.col_label(ci);
-                let w = header.width() as u16;
-                if w > widths[ci] {
-                    widths[ci] = w;
-                }
-            }
-            // Measure cell content
-            if layout.is_records_mode() {
-                for ri in 0..layout.row_count() {
-                    for (ci, wref) in widths.iter_mut().enumerate().take(n) {
-                        let s = self.records_cell_text(&layout, ri, ci);
-                        let w = s.width() as u16;
-                        if w > *wref {
-                            *wref = w;
-                        }
-                    }
-                }
-            } else {
-                // Pivot mode: measure formatted cell values
-                for ri in 0..layout.row_count() {
-                    for (ci, wref) in widths.iter_mut().enumerate().take(n) {
-                        if let Some(key) = layout.cell_key(ri, ci) {
-                            let value =
-                                self.model.evaluate_aggregated(&key, &layout.none_cats);
-                            let s = format_value(value.as_ref(), fmt_comma, fmt_decimals);
-                            let w = s.width() as u16;
-                            if w > *wref {
-                                *wref = w;
-                            }
-                        }
-                    }
-                }
-            }
-            // +1 for gap between columns
-            widths
-                .into_iter()
-                .map(|w| (w + 1).max(MIN_COL_WIDTH).min(MAX_COL_WIDTH))
-                .collect()
-        };
+        let col_widths = compute_col_widths(self.model, layout, fmt_comma, fmt_decimals);
 
         // ── Adaptive row header widths ───────────────────────────────
-        // Measure the widest label at each row-header level.
         let data_row_items: Vec<&Vec<String>> = layout
             .row_items
             .iter()
@@ -187,9 +128,7 @@ impl<'a> GridWidget<'a> {
             v
         };
         let col_x_at = |ci: usize| -> u16 {
-            area.x
-                + row_header_width
-                + col_x[ci].saturating_sub(col_x[col_offset])
+            area.x + row_header_width + col_x[ci].saturating_sub(col_x[col_offset])
         };
         let col_w_at = |ci: usize| -> u16 { *col_widths.get(ci).unwrap_or(&MIN_COL_WIDTH) };
 
@@ -240,7 +179,11 @@ impl<'a> GridWidget<'a> {
                 buf.set_string(
                     x,
                     y,
-                    format!("{:<width$}", truncate(&label, cw.saturating_sub(1)), width = cw),
+                    format!(
+                        "{:<width$}",
+                        truncate(&label, cw.saturating_sub(1)),
+                        width = cw
+                    ),
                     group_style,
                 );
             }
@@ -292,7 +235,11 @@ impl<'a> GridWidget<'a> {
                 buf.set_string(
                     x,
                     y,
-                    format!("{:>width$}", truncate(&label, cw.saturating_sub(1)), width = cw),
+                    format!(
+                        "{:>width$}",
+                        truncate(&label, cw.saturating_sub(1)),
+                        width = cw
+                    ),
                     styled,
                 );
             }
@@ -410,23 +357,17 @@ impl<'a> GridWidget<'a> {
                         }
                         let cw = col_w_at(ci) as usize;
 
-                        let (cell_str, value) = if layout.is_records_mode() {
-                            let s = self.records_cell_text(&layout, ri, ci);
-                            // In records mode the value is a string, not aggregated
-                            let v = if !s.is_empty() {
-                                Some(crate::model::cell::CellValue::Text(s.clone()))
+                        // Check pending drill edits first, then use display_text
+                        let cell_str = if let Some(ds) = self.drill_state {
+                            let col_name = layout.col_label(ci);
+                            ds.pending_edits
+                                .get(&(ri, col_name))
+                                .cloned()
+                                .unwrap_or_else(|| {
+                                    layout.display_text(self.model, ri, ci, fmt_comma, fmt_decimals)
+                                })
                         } else {
-                                None
-                            };
-                            (s, v)
-                        } else {
-                            let key = match layout.cell_key(ri, ci) {
-                                Some(k) => k,
-                                None => continue,
-                            };
-                            let value = self.model.evaluate_aggregated(&key, &layout.none_cats);
-                            let s = format_value(value.as_ref(), fmt_comma, fmt_decimals);
-                            (s, value)
+                            layout.display_text(self.model, ri, ci, fmt_comma, fmt_decimals)
                         };
                         let is_selected = ri == sel_row && ci == sel_col;
                         let is_search_match = !self.search_query.is_empty()
@@ -453,13 +394,13 @@ impl<'a> GridWidget<'a> {
                         } else if is_search_match {
                             Style::default().fg(Color::Black).bg(Color::Yellow)
                         } else if is_sel_row {
-                            let fg = if value.is_none() {
+                            let fg = if cell_str.is_empty() {
                                 Color::DarkGray
                             } else {
                                 Color::White
                             };
                             Style::default().fg(fg).bg(ROW_HIGHLIGHT_BG)
-                        } else if value.is_none() {
+                        } else if cell_str.is_empty() {
                             Style::default().fg(Color::DarkGray)
                         } else {
                             Style::default()
@@ -561,9 +502,9 @@ impl<'a> Widget for GridWidget<'a> {
         block.render(area, buf);
 
         // Page axis bar
-        let layout = GridLayout::new(self.model, self.model.active_view());
-        if !layout.page_coords.is_empty() && inner.height > 0 {
-            let page_info: Vec<String> = layout
+        if !self.layout.page_coords.is_empty() && inner.height > 0 {
+            let page_info: Vec<String> = self
+                .layout
                 .page_coords
                 .iter()
                 .map(|(cat, sel)| format!("{cat} = {sel}"))
@@ -588,52 +529,122 @@ impl<'a> Widget for GridWidget<'a> {
     }
 }
 
-fn format_value(v: Option<&CellValue>, comma: bool, decimals: u8) -> String {
-    match v {
-        Some(CellValue::Number(n)) => format_f64(*n, comma, decimals),
-        Some(CellValue::Text(s)) => s.clone(),
-        None => String::new(),
-    }
-}
-
-pub fn parse_number_format(fmt: &str) -> (bool, u8) {
-    let comma = fmt.contains(',');
-    let decimals = fmt
-        .rfind('.')
-        .and_then(|i| fmt[i + 1..].parse::<u8>().ok())
-        .unwrap_or(0);
-    (comma, decimals)
-}
-
-pub fn format_f64(n: f64, comma: bool, decimals: u8) -> String {
-    let formatted = format!("{:.prec$}", n, prec = decimals as usize);
-    if !comma {
-        return formatted;
-    }
-    // Split integer and decimal parts
-    let (int_part, dec_part) = if let Some(dot) = formatted.find('.') {
-        (&formatted[..dot], Some(&formatted[dot..]))
+/// Compute adaptive column widths for pivot mode (header labels + cell values).
+/// Header widths use the widest *individual* level label (not the joined
+/// multi-level string), matching how the grid renderer draws each level on
+/// its own row with repeat-suppression.
+pub fn compute_col_widths(
+    model: &Model,
+    layout: &GridLayout,
+    fmt_comma: bool,
+    fmt_decimals: u8,
+) -> Vec<u16> {
+    let n = layout.col_count();
+    let mut widths = vec![0u16; n];
+    // Measure individual header level labels
+    let data_col_items: Vec<&Vec<String>> = layout
+        .col_items
+        .iter()
+        .filter_map(|e| {
+            if let AxisEntry::DataItem(v) = e {
+                Some(v)
             } else {
-        (&formatted[..], None)
-    };
-    let is_neg = int_part.starts_with('-');
-    let digits = if is_neg { &int_part[1..] } else { int_part };
-    let mut result = String::new();
-    for (idx, c) in digits.chars().rev().enumerate() {
-        if idx > 0 && idx % 3 == 0 {
-            result.push(',');
+                None
             }
-        result.push(c);
+        })
+        .collect();
+    for (ci, wref) in widths.iter_mut().enumerate().take(n) {
+        if let Some(levels) = data_col_items.get(ci) {
+            let max_level_w = levels.iter().map(|s| s.width() as u16).max().unwrap_or(0);
+            if max_level_w > *wref {
+                *wref = max_level_w;
             }
-    if is_neg {
-        result.push('-');
         }
-    let mut out: String = result.chars().rev().collect();
-    if let Some(dec) = dec_part {
-        out.push_str(dec);
     }
-    out
+    // Measure cell content widths (works for both pivot and records modes)
+    for ri in 0..layout.row_count() {
+        for (ci, wref) in widths.iter_mut().enumerate().take(n) {
+            let s = layout.display_text(model, ri, ci, fmt_comma, fmt_decimals);
+            let w = s.width() as u16;
+            if w > *wref {
+                *wref = w;
             }
+        }
+    }
+    // Measure total row (column sums) — pivot mode only
+    if !layout.is_records_mode() && layout.row_count() > 0 {
+        for (ci, wref) in widths.iter_mut().enumerate().take(n) {
+            let total: f64 = (0..layout.row_count())
+                .filter_map(|ri| layout.cell_key(ri, ci))
+                .map(|key| model.evaluate_aggregated_f64(&key, &layout.none_cats))
+                .sum();
+            let s = format_f64(total, fmt_comma, fmt_decimals);
+            let w = s.width() as u16;
+            if w > *wref {
+                *wref = w;
+            }
+        }
+    }
+    widths
+        .into_iter()
+        .map(|w| (w + 1).max(MIN_COL_WIDTH).min(MAX_COL_WIDTH))
+        .collect()
+}
+
+/// Compute the total row header width from the layout's row items.
+pub fn compute_row_header_width(layout: &GridLayout) -> u16 {
+    let n_row_levels = layout.row_cats.len().max(1);
+    let data_row_items: Vec<&Vec<String>> = layout
+        .row_items
+        .iter()
+        .filter_map(|e| {
+            if let AxisEntry::DataItem(v) = e {
+                Some(v)
+            } else {
+                None
+            }
+        })
+        .collect();
+    let sub_widths: Vec<u16> = (0..n_row_levels)
+        .map(|d| {
+            let max_label = data_row_items
+                .iter()
+                .filter_map(|v| v.get(d))
+                .map(|s| s.width() as u16)
+                .max()
+                .unwrap_or(0);
+            (max_label + 1).max(MIN_ROW_HEADER_W).min(MAX_ROW_HEADER_W)
+        })
+        .collect();
+    sub_widths.iter().sum()
+}
+
+/// Count how many columns fit starting from `col_offset` given the available width.
+pub fn compute_visible_cols(
+    col_widths: &[u16],
+    row_header_width: u16,
+    term_width: u16,
+    col_offset: usize,
+) -> usize {
+    // Account for grid border (2 chars)
+    let data_area_width = term_width
+        .saturating_sub(2)
+        .saturating_sub(row_header_width);
+    let mut acc = 0u16;
+    let mut count = 0usize;
+    for ci in col_offset..col_widths.len() {
+        let w = col_widths[ci];
+        if acc + w > data_area_width {
+            break;
+        }
+        acc += w;
+        count += 1;
+    }
+    count.max(1)
+}
+
+// Re-export shared formatting functions
+pub use crate::format::{format_f64, parse_number_format};
 
 fn truncate(s: &str, max_width: usize) -> String {
     let w = s.width();
@@ -666,6 +677,7 @@ mod tests {
     use crate::model::cell::{CellKey, CellValue};
     use crate::model::Model;
     use crate::ui::app::AppMode;
+    use crate::view::GridLayout;
 
     // ── Helpers ───────────────────────────────────────────────────────────────
 
@@ -674,7 +686,8 @@ mod tests {
         let area = Rect::new(0, 0, width, height);
         let mut buf = Buffer::empty(area);
         let bufs = std::collections::HashMap::new();
-        GridWidget::new(model, &AppMode::Normal, "", &bufs, None).render(area, &mut buf);
+        let layout = GridLayout::new(model, model.active_view());
+        GridWidget::new(model, &layout, &AppMode::Normal, "", &bufs, None).render(area, &mut buf);
         buf
     }
 
@@ -720,10 +733,7 @@ mod tests {
         // Fill every cell so nothing is pruned as empty.
         for t in ["Food", "Clothing"] {
             for mo in ["Jan", "Feb"] {
-                m.set_cell(
-                    coord(&[("Type", t), ("Month", mo)]),
-                    CellValue::Number(1.0),
-                );
+                m.set_cell(coord(&[("Type", t), ("Month", mo)]), CellValue::Number(1.0));
             }
         }
         m

src/ui/tile_bar.rs

@@ -4,20 +4,12 @@ use ratatui::{
     style::{Color, Modifier, Style},
     widgets::Widget,
 };
+use unicode_width::UnicodeWidthStr;
 
 use crate::model::Model;
 use crate::ui::app::AppMode;
 use crate::view::Axis;
 
-fn axis_display(axis: Axis) -> (&'static str, Color) {
-    match axis {
-        Axis::Row => ("↕", Color::Green),
-        Axis::Column => ("↔", Color::Blue),
-        Axis::Page => ("☰", Color::Magenta),
-        Axis::None => ("∅", Color::DarkGray),
-    }
-}
-
 pub struct TileBar<'a> {
     pub model: &'a Model,
     pub mode: &'a AppMode,
@@ -32,10 +24,26 @@ impl<'a> TileBar<'a> {
             tile_cat_idx,
         }
     }
+    fn axis_display(axis: Axis) -> (&'static str, Color) {
+        match axis {
+            Axis::Row => ("|", Color::Green),
+            Axis::Column => ("-", Color::Blue),
+            Axis::Page => ("=", Color::Magenta),
+            Axis::None => (".", Color::DarkGray),
+        }
+    }
 }
 
 impl<'a> Widget for TileBar<'a> {
     fn render(self, area: Rect, buf: &mut Buffer) {
+        // Clear the line to avoid stale characters from previous renders
+        buf.set_string(
+            area.x,
+            area.y,
+            " ".repeat(area.width as usize),
+            Style::default(),
+        );
+
         let view = self.model.active_view();
 
         let selected_cat_idx = if matches!(self.mode, AppMode::TileSelect) {
@@ -50,7 +58,7 @@ impl<'a> Widget for TileBar<'a> {
 
         let cat_names: Vec<&str> = self.model.category_names();
         for (i, cat_name) in cat_names.iter().enumerate() {
-            let (axis_symbol, axis_color) = axis_display(view.axis_of(cat_name));
+            let (axis_symbol, axis_color) = TileBar::axis_display(view.axis_of(cat_name));
             let label = format!(" [{cat_name} {axis_symbol}] ");
             let is_selected = selected_cat_idx == Some(i);
 
@@ -63,22 +71,23 @@ impl<'a> Widget for TileBar<'a> {
                 Style::default().fg(axis_color)
             };
 
-            if x + label.len() as u16 > area.x + area.width {
+            let label_w = label.width() as u16;
+            if x + label_w > area.x + area.width {
                 break;
             }
             buf.set_string(x, area.y, &label, style);
-            x += label.len() as u16;
+            x += label_w;
         }
 
         // Hint
         if matches!(self.mode, AppMode::TileSelect) {
             let hint = " [Enter] cycle axis  [r/c/p] set axis  [←→] select  [Esc] cancel";
-            if x + hint.len() as u16 <= area.x + area.width {
+            if x + hint.width() as u16 <= area.x + area.width {
                 buf.set_string(x, area.y, hint, Style::default().fg(Color::DarkGray));
             }
         } else {
             let hint = " Ctrl+↑↓←→ to move tiles";
-            if x + hint.len() as u16 <= area.x + area.width {
+            if x + hint.width() as u16 <= area.x + area.width {
                 buf.set_string(x, area.y, hint, Style::default().fg(Color::DarkGray));
             }
         }

src/ui/view_panel.rs

@@ -36,7 +36,7 @@ impl<'a> Widget for ViewPanel<'a> {
         let block = Block::default()
             .borders(Borders::ALL)
             .border_style(border_style)
-            .title(" Views [Enter] switch [n]ew [d]elete ");
+            .title(" Views ");
         let inner = block.inner(area);
         block.render(area, buf);
 

src/view/layout.rs

@@ -1,7 +1,17 @@
+use std::rc::Rc;
+
 use crate::model::cell::{CellKey, CellValue};
 use crate::model::Model;
 use crate::view::{Axis, View};
 
+/// Extract (record_index, dim_name) from a synthetic records-mode CellKey.
+/// Returns None for normal pivot-mode keys.
+pub fn synthetic_record_info(key: &CellKey) -> Option<(usize, String)> {
+    let idx: usize = key.get("_Index")?.parse().ok()?;
+    let dim = key.get("_Dim")?.to_string();
+    Some((idx, dim))
+}
+
 /// One entry on a grid axis: either a visual group header or a data-item tuple.
 ///
 /// `GroupHeader` entries are always visible so the user can see the group label
@@ -30,8 +40,8 @@ pub struct GridLayout {
     /// Categories on `Axis::None` — hidden, implicitly aggregated.
     pub none_cats: Vec<String>,
     /// In records mode: the filtered cell list, one per row.
-    /// None for normal pivot views.
-    pub records: Option<Vec<(CellKey, CellValue)>>,
+    /// None for normal pivot views. Rc for cheap sharing.
+    pub records: Option<Rc<Vec<(CellKey, CellValue)>>>,
 }
 
 impl GridLayout {
@@ -40,12 +50,11 @@ impl GridLayout {
     pub fn with_frozen_records(
         model: &Model,
         view: &View,
-        frozen_records: Option<Vec<(CellKey, CellValue)>>,
+        frozen_records: Option<Rc<Vec<(CellKey, CellValue)>>>,
     ) -> Self {
         let mut layout = Self::new(model, view);
         if layout.is_records_mode() {
             if let Some(records) = frozen_records {
-                // Re-build with the frozen records instead
                 let row_items: Vec<AxisEntry> = (0..records.len())
                     .map(|i| AxisEntry::DataItem(vec![i.to_string()]))
                     .collect();
@@ -175,7 +184,7 @@ impl GridLayout {
             row_items,
             col_items,
             none_cats,
-            records: Some(records),
+            records: Some(Rc::new(records)),
         }
     }
 
@@ -220,14 +229,10 @@ impl GridLayout {
         let mut has_value = vec![vec![false; cc]; rc];
         for ri in 0..rc {
             for ci in 0..cc {
-                has_value[ri][ci] = if self.is_records_mode() {
-                    let s = self.records_display(ri, ci).unwrap_or_default();
-                    !s.is_empty()
-                } else {
-                    self.cell_key(ri, ci)
+                has_value[ri][ci] = self
+                    .cell_key(ri, ci)
                     .and_then(|k| model.evaluate_aggregated(&k, &self.none_cats))
-                        .is_some()
-                };
+                    .is_some();
             }
         }
 
@@ -297,7 +302,7 @@ impl GridLayout {
                 .map(|i| AxisEntry::DataItem(vec![i.to_string()]))
                 .collect();
             self.row_items = new_row_items;
-            self.records = Some(new_records);
+            self.records = Some(Rc::new(new_records));
         }
     }
 
@@ -352,18 +357,57 @@ impl GridLayout {
             .unwrap_or_default()
     }
 
+    /// Resolve the display string for a synthetic records-mode CellKey.
+    /// Returns None for non-synthetic (pivot) keys.
+    pub fn resolve_display(&self, key: &CellKey) -> Option<String> {
+        let (idx, dim) = synthetic_record_info(key)?;
+        let records = self.records.as_ref()?;
+        let (orig_key, value) = records.get(idx)?;
+        if dim == "Value" {
+            Some(value.to_string())
+        } else {
+            Some(orig_key.get(&dim).unwrap_or("").to_string())
+        }
+    }
+
+    /// Unified display text for a cell at (row, col). Handles both pivot and
+    /// records modes. In pivot mode, evaluates and formats the cell value.
+    /// In records mode, resolves via the frozen records snapshot.
+    pub fn display_text(
+        &self,
+        model: &Model,
+        row: usize,
+        col: usize,
+        fmt_comma: bool,
+        fmt_decimals: u8,
+    ) -> String {
+        if self.is_records_mode() {
+            self.records_display(row, col).unwrap_or_default()
+        } else {
+            self.cell_key(row, col)
+                .and_then(|key| model.evaluate_aggregated(&key, &self.none_cats))
+                .map(|v| crate::format::format_value(Some(&v), fmt_comma, fmt_decimals))
+                .unwrap_or_default()
+        }
+    }
+
     /// Build the CellKey for the data cell at (row, col), including the active
     /// page-axis filter. Returns None if row or col is out of bounds.
-    /// In records mode: returns the real underlying CellKey when the column
-    /// is "Value" (editable); returns None for coord columns (read-only).
+    /// In records mode: returns a synthetic `(_Index, _Dim)` key for every column.
     pub fn cell_key(&self, row: usize, col: usize) -> Option<CellKey> {
-        if let Some(records) = &self.records {
-            // Records mode: only the Value column maps to a real, editable cell.
-            if self.col_label(col) == "Value" {
-                return records.get(row).map(|(k, _)| k.clone());
-            } else {
+        if self.records.is_some() {
+            let records = self.records.as_ref().unwrap();
+            if row >= records.len() {
                 return None;
             }
+            let col_label = self.col_label(col);
+            if col_label.is_empty() {
+                return None;
+            }
+            return Some(CellKey::new(vec![
+                ("_Index".to_string(), row.to_string()),
+                ("_Dim".to_string(), col_label),
+            ]));
         }
         let row_item = self
             .row_items
@@ -527,7 +571,7 @@ fn cross_product(model: &Model, view: &View, cats: &[String]) -> Vec<AxisEntry>
 
 #[cfg(test)]
 mod tests {
-    use super::{AxisEntry, GridLayout};
+    use super::{synthetic_record_info, AxisEntry, GridLayout};
     use crate::model::cell::{CellKey, CellValue};
     use crate::model::Model;
     use crate::view::Axis;
@@ -566,10 +610,7 @@ mod tests {
         m.category_mut("Col").unwrap().add_item("Y");
         // Only X has data; Y is entirely empty
         m.set_cell(
-            CellKey::new(vec![
-                ("Row".into(), "A".into()),
-                ("Col".into(), "X".into()),
-            ]),
+            CellKey::new(vec![("Row".into(), "A".into()), ("Col".into(), "X".into())]),
             CellValue::Number(1.0),
         );
 
@@ -592,40 +633,73 @@ mod tests {
     }
 
     #[test]
-    fn records_mode_cell_key_editable_for_value_column() {
+    fn records_mode_cell_key_returns_synthetic_for_all_columns() {
         let mut m = records_model();
         let v = m.active_view_mut();
         v.set_axis("_Index", Axis::Row);
         v.set_axis("_Dim", Axis::Column);
         let layout = GridLayout::new(&m, m.active_view());
         assert!(layout.is_records_mode());
-        // Find the "Value" column index
-        let cols: Vec<String> = (0..layout.col_count()).map(|i| layout.col_label(i)).collect();
+        let cols: Vec<String> = (0..layout.col_count())
+            .map(|i| layout.col_label(i))
+            .collect();
+        // All columns return synthetic keys
         let value_col = cols.iter().position(|c| c == "Value").unwrap();
-        // cell_key should be Some for Value column
-        let key = layout.cell_key(0, value_col);
-        assert!(key.is_some(), "Value column should be editable");
-        // cell_key should be None for coord columns
+        let key = layout.cell_key(0, value_col).unwrap();
+        assert_eq!(key.get("_Index"), Some("0"));
+        assert_eq!(key.get("_Dim"), Some("Value"));
+
         let region_col = cols.iter().position(|c| c == "Region").unwrap();
-        assert!(
-            layout.cell_key(0, region_col).is_none(),
-            "Region column should not be editable"
-        );
+        let key = layout.cell_key(0, region_col).unwrap();
+        assert_eq!(key.get("_Index"), Some("0"));
+        assert_eq!(key.get("_Dim"), Some("Region"));
     }
 
     #[test]
-    fn records_mode_cell_key_maps_to_real_cell() {
+    fn records_mode_resolve_display_returns_values() {
         let mut m = records_model();
         let v = m.active_view_mut();
         v.set_axis("_Index", Axis::Row);
         v.set_axis("_Dim", Axis::Column);
         let layout = GridLayout::new(&m, m.active_view());
-        let cols: Vec<String> = (0..layout.col_count()).map(|i| layout.col_label(i)).collect();
+        let cols: Vec<String> = (0..layout.col_count())
+            .map(|i| layout.col_label(i))
+            .collect();
+
+        // Value column resolves to the cell value
         let value_col = cols.iter().position(|c| c == "Value").unwrap();
-        // The CellKey at (0, Value) should look up a real cell value
         let key = layout.cell_key(0, value_col).unwrap();
-        let val = m.evaluate(&key);
-        assert!(val.is_some(), "cell_key should resolve to a real cell");
+        let display = layout.resolve_display(&key);
+        assert!(display.is_some(), "Value column should resolve");
+
+        // Category column resolves to the coordinate value
+        let region_col = cols.iter().position(|c| c == "Region").unwrap();
+        let key = layout.cell_key(0, region_col).unwrap();
+        let display = layout.resolve_display(&key).unwrap();
+        assert!(
+            !display.is_empty(),
+            "Region column should resolve to a value"
+        );
+    }
+
+    #[test]
+    fn synthetic_record_info_returns_none_for_pivot_keys() {
+        let key = CellKey::new(vec![
+            ("Region".to_string(), "East".to_string()),
+            ("Product".to_string(), "Shoes".to_string()),
+        ]);
+        assert!(synthetic_record_info(&key).is_none());
+    }
+
+    #[test]
+    fn synthetic_record_info_extracts_index_and_dim() {
+        let key = CellKey::new(vec![
+            ("_Index".to_string(), "3".to_string()),
+            ("_Dim".to_string(), "Region".to_string()),
+        ]);
+        let (idx, dim) = synthetic_record_info(&key).unwrap();
+        assert_eq!(idx, 3);
+        assert_eq!(dim, "Region");
     }
 
     fn coord(pairs: &[(&str, &str)]) -> CellKey {

src/view/mod.rs

@@ -3,5 +3,5 @@ pub mod layout;
 pub mod types;
 
 pub use axis::Axis;
-pub use layout::{AxisEntry, GridLayout};
+pub use layout::{synthetic_record_info, AxisEntry, GridLayout};
 pub use types::View;