refactor: cleanup entry point

src/main.rs

@@ -1,10 +1,10 @@
-mod model;
-mod formula;
-mod view;
-mod ui;
-mod import;
-mod persistence;
 mod command;
+mod formula;
+mod import;
+mod model;
+mod persistence;
+mod ui;
+mod view;
 
 use std::io;
 use std::path::PathBuf;
@@ -24,18 +24,24 @@ use ratatui::{
     Frame, Terminal,
 };
 
+use model::Model;
 use ui::app::{App, AppMode};
-use ui::grid::GridWidget;
-use ui::tile_bar::TileBar;
-use ui::formula_panel::FormulaPanel;
 use ui::category_panel::CategoryPanel;
-use ui::view_panel::ViewPanel;
+use ui::formula_panel::FormulaPanel;
+use ui::grid::GridWidget;
 use ui::help::HelpWidget;
 use ui::import_wizard_ui::ImportWizardWidget;
-use model::Model;
+use ui::tile_bar::TileBar;
+use ui::view_panel::ViewPanel;
 
-fn main() -> Result<()> {
+struct CmdLineArgs {
-    let args: Vec<String> = std::env::args().collect();
+    file_path: Option<PathBuf>,
+    headless_cmds: Vec<String>,
+    headless_script: Option<PathBuf>,
+    import_path: Option<PathBuf>,
+}
+
+fn parse_args(args: Vec<String>) -> Option<CmdLineArgs> {
     let mut file_path: Option<PathBuf> = None;
     let mut headless_cmds: Vec<String> = Vec::new();
     let mut headless_script: Option<PathBuf> = None;
@@ -60,7 +66,7 @@ fn main() -> Result<()> {
             }
             "--help" | "-h" => {
                 print_usage();
-                return Ok(());
+                return None;
             }
             arg if !arg.starts_with('-') => {
                 file_path = Some(PathBuf::from(arg));
@@ -70,15 +76,33 @@ fn main() -> Result<()> {
         i += 1;
     }
 
+    return Some(CmdLineArgs {
+        file_path,
+        headless_cmds,
+        headless_script,
+        import_path,
+    });
+}
+
+fn main() -> Result<()> {
+    let args: Vec<String> = std::env::args().collect();
+    let maybe_cmd_line_args = parse_args(args);
+
+    if maybe_cmd_line_args.is_none() {
+        return Ok(());
+    }
+    let cmd_line_args = maybe_cmd_line_args.unwrap();
+
     // Load or create model
-    let mut model = if let Some(ref path) = file_path {
+    let mut model = if let Some(ref path) = cmd_line_args.file_path {
         if path.exists() {
             let mut m = persistence::load(path)
                 .with_context(|| format!("Failed to load {}", path.display()))?;
             m.normalize_view_state();
             m
         } else {
-            let name = path.file_stem()
+            let name = path
+                .file_stem()
                 .and_then(|s| s.to_str())
                 .unwrap_or("New Model")
                 .to_string();
@@ -89,24 +113,35 @@ fn main() -> Result<()> {
     };
 
     // Headless mode
-    if !headless_cmds.is_empty() || headless_script.is_some() {
+    if !cmd_line_args.headless_cmds.is_empty() || cmd_line_args.headless_script.is_some() {
-        return run_headless(&mut model, file_path, headless_cmds, headless_script);
+        return run_headless(
+            &mut model,
+            cmd_line_args.file_path,
+            cmd_line_args.headless_cmds,
+            cmd_line_args.headless_script,
+        );
     }
 
     // Pre-TUI import: parse JSON and open wizard
-    let import_json = if let Some(ref path) = import_path {
+    let import_json = if let Some(ref path) = cmd_line_args.import_path {
         match std::fs::read_to_string(path) {
-            Err(e) => { eprintln!("Cannot read '{}': {e}", path.display()); return Ok(()); }
+            Err(e) => {
-            Ok(content) => match serde_json::from_str::<serde_json::Value>(&content) {
+                eprintln!("Cannot read '{}': {e}", path.display());
-                Err(e) => { eprintln!("JSON parse error: {e}"); return Ok(()); }
+                return Ok(());
-                Ok(json) => Some(json),
             }
+            Ok(content) => match serde_json::from_str::<serde_json::Value>(&content) {
+                Err(e) => {
+                    eprintln!("JSON parse error: {e}");
+                    return Ok(());
+                }
+                Ok(json) => Some(json),
+            },
         }
     } else {
         None
     };
 
-    run_tui(model, file_path, import_json)
+    run_tui(model, cmd_line_args.file_path, import_json)
 }
 
 fn run_headless(
@@ -138,7 +173,9 @@ fn run_headless(
             }
         };
         let result = command::dispatch(model, &parsed);
-        if !result.ok { exit_code = 1; }
+        if !result.ok {
+            exit_code = 1;
+        }
         println!("{}", serde_json::to_string(&result)?);
     }
 
@@ -149,7 +186,11 @@ fn run_headless(
     std::process::exit(exit_code);
 }
 
-fn run_tui(model: Model, file_path: Option<PathBuf>, import_json: Option<serde_json::Value>) -> Result<()> {
+fn run_tui(
+    model: Model,
+    file_path: Option<PathBuf>,
+    import_json: Option<serde_json::Value>,
+) -> Result<()> {
     enable_raw_mode()?;
     let mut stdout = io::stdout();
     execute!(stdout, EnterAlternateScreen)?;
@@ -228,7 +269,9 @@ fn draw(f: &mut Frame, app: &App) {
 
 fn draw_title(f: &mut Frame, area: Rect, app: &App) {
     let dirty = if app.dirty { " [+]" } else { "" };
-    let file = app.file_path.as_ref()
+    let file = app
+        .file_path
+        .as_ref()
         .and_then(|p| p.file_name())
         .and_then(|n| n.to_str())
         .map(|n| format!(" ({n})"))
@@ -238,8 +281,12 @@ fn draw_title(f: &mut Frame, area: Rect, app: &App) {
     let pad = " ".repeat((area.width as usize).saturating_sub(title.len() + right.len()));
     let line = format!("{title}{pad}{right}");
     f.render_widget(
-        Paragraph::new(line)
+        Paragraph::new(line).style(
-            .style(Style::default().fg(Color::Black).bg(Color::Blue).add_modifier(Modifier::BOLD)),
+            Style::default()
+                .fg(Color::Black)
+                .bg(Color::Blue)
+                .add_modifier(Modifier::BOLD),
+        ),
         area,
     );
 }
@@ -254,30 +301,51 @@ fn draw_content(f: &mut Frame, area: Rect, app: &App) {
             .constraints([Constraint::Min(40), Constraint::Length(side_w)])
             .split(area);
 
-        f.render_widget(GridWidget::new(&app.model, &app.mode, &app.search_query), chunks[0]);
+        f.render_widget(
+            GridWidget::new(&app.model, &app.mode, &app.search_query),
+            chunks[0],
+        );
 
         let side = chunks[1];
-        let panel_count = [app.formula_panel_open, app.category_panel_open, app.view_panel_open]
+        let panel_count = [
-            .iter().filter(|&&b| b).count() as u16;
+            app.formula_panel_open,
+            app.category_panel_open,
+            app.view_panel_open,
+        ]
+        .iter()
+        .filter(|&&b| b)
+        .count() as u16;
         let ph = side.height / panel_count.max(1);
         let mut y = side.y;
 
         if app.formula_panel_open {
             let a = Rect::new(side.x, y, side.width, ph);
-            f.render_widget(FormulaPanel::new(&app.model, &app.mode, app.formula_cursor), a);
+            f.render_widget(
+                FormulaPanel::new(&app.model, &app.mode, app.formula_cursor),
+                a,
+            );
             y += ph;
         }
         if app.category_panel_open {
             let a = Rect::new(side.x, y, side.width, ph);
-            f.render_widget(CategoryPanel::new(&app.model, &app.mode, app.cat_panel_cursor), a);
+            f.render_widget(
+                CategoryPanel::new(&app.model, &app.mode, app.cat_panel_cursor),
+                a,
+            );
             y += ph;
         }
         if app.view_panel_open {
             let a = Rect::new(side.x, y, side.width, ph);
-            f.render_widget(ViewPanel::new(&app.model, &app.mode, app.view_panel_cursor), a);
+            f.render_widget(
+                ViewPanel::new(&app.model, &app.mode, app.view_panel_cursor),
+                a,
+            );
         }
     } else {
-        f.render_widget(GridWidget::new(&app.model, &app.mode, &app.search_query), area);
+        f.render_widget(
+            GridWidget::new(&app.model, &app.mode, &app.search_query),
+            area,
+        );
     }
 }
 
@@ -320,10 +388,7 @@ fn draw_status(f: &mut Frame, area: Rect, app: &App) {
 
     let left = format!("  {mode_badge}{search_part}  {msg}");
     let right = view_badge;
-    let pad = " ".repeat(
+    let pad = " ".repeat((area.width as usize).saturating_sub(left.len() + right.len()));
-        (area.width as usize)
-            .saturating_sub(left.len() + right.len()),
-    );
     let line = format!("{left}{pad}{right}");
 
     let badge_style = match &app.mode {
@@ -337,7 +402,11 @@ fn draw_status(f: &mut Frame, area: Rect, app: &App) {
 }
 
 fn draw_command_bar(f: &mut Frame, area: Rect, app: &App) {
-    let buf = if let AppMode::CommandMode { buffer } = &app.mode { buffer.as_str() } else { "" };
+    let buf = if let AppMode::CommandMode { buffer } = &app.mode {
+        buffer.as_str()
+    } else {
+        ""
+    };
     let line = format!(":{buf}▌");
     f.render_widget(
         Paragraph::new(line).style(Style::default().fg(Color::White).bg(Color::Black)),
@@ -346,7 +415,11 @@ fn draw_command_bar(f: &mut Frame, area: Rect, app: &App) {
 }
 
 fn draw_export_prompt(f: &mut Frame, area: Rect, app: &App) {
-    let buf = if let AppMode::ExportPrompt { buffer } = &app.mode { buffer.as_str() } else { "" };
+    let buf = if let AppMode::ExportPrompt { buffer } = &app.mode {
+        buffer.as_str()
+    } else {
+        ""
+    };
     let popup_w = 64u16.min(area.width);
     let x = area.x + area.width.saturating_sub(popup_w) / 2;
     let y = area.y + area.height / 2;
@@ -360,8 +433,7 @@ fn draw_export_prompt(f: &mut Frame, area: Rect, app: &App) {
     let inner = block.inner(popup_area);
     f.render_widget(block, popup_area);
     f.render_widget(
-        Paragraph::new(format!("{buf}▌"))
+        Paragraph::new(format!("{buf}▌")).style(Style::default().fg(Color::Green)),
-            .style(Style::default().fg(Color::Green)),
         inner,
     );
 }
@@ -383,32 +455,82 @@ fn draw_welcome(f: &mut Frame, area: Rect, _app: &App) {
     f.render_widget(block, popup);
 
     let lines: &[(&str, Style)] = &[
-        ("Multi-dimensional data modeling — in your terminal.", Style::default().fg(Color::White)),
+        (
+            "Multi-dimensional data modeling — in your terminal.",
+            Style::default().fg(Color::White),
+        ),
         ("", Style::default()),
-        ("Getting started", Style::default().fg(Color::Blue).add_modifier(Modifier::BOLD)),
+        (
+            "Getting started",
+            Style::default()
+                .fg(Color::Blue)
+                .add_modifier(Modifier::BOLD),
+        ),
         ("", Style::default()),
-        (":import <file.json>    Import a JSON file", Style::default().fg(Color::Cyan)),
+        (
-        (":add-cat <name>        Add a category (dimension)", Style::default().fg(Color::Cyan)),
+            ":import <file.json>    Import a JSON file",
-        (":add-item <cat> <name> Add an item to a category", Style::default().fg(Color::Cyan)),
+            Style::default().fg(Color::Cyan),
-        (":formula <cat> <expr>  Add a formula, e.g.:", Style::default().fg(Color::Cyan)),
+        ),
-        ("  Profit = Revenue - Cost", Style::default().fg(Color::Green)),
+        (
-        (":w <file.improv>       Save your model", Style::default().fg(Color::Cyan)),
+            ":add-cat <name>        Add a category (dimension)",
+            Style::default().fg(Color::Cyan),
+        ),
+        (
+            ":add-item <cat> <name> Add an item to a category",
+            Style::default().fg(Color::Cyan),
+        ),
+        (
+            ":formula <cat> <expr>  Add a formula, e.g.:",
+            Style::default().fg(Color::Cyan),
+        ),
+        (
+            "  Profit = Revenue - Cost",
+            Style::default().fg(Color::Green),
+        ),
+        (
+            ":w <file.improv>       Save your model",
+            Style::default().fg(Color::Cyan),
+        ),
         ("", Style::default()),
-        ("Navigation", Style::default().fg(Color::Blue).add_modifier(Modifier::BOLD)),
+        (
+            "Navigation",
+            Style::default()
+                .fg(Color::Blue)
+                .add_modifier(Modifier::BOLD),
+        ),
         ("", Style::default()),
-        ("F C V                  Open panels (Formulas/Categories/Views)", Style::default()),
+        (
-        ("T                      Tile-select: pivot rows ↔ cols ↔ page", Style::default()),
+            "F C V                  Open panels (Formulas/Categories/Views)",
+            Style::default(),
+        ),
+        (
+            "T                      Tile-select: pivot rows ↔ cols ↔ page",
+            Style::default(),
+        ),
         ("i  Enter               Edit a cell", Style::default()),
-        ("[ ]                    Cycle the page-axis filter", Style::default()),
+        (
-        ("?  or  :help           Full key reference", Style::default()),
+            "[ ]                    Cycle the page-axis filter",
+            Style::default(),
+        ),
+        (
+            "?  or  :help           Full key reference",
+            Style::default(),
+        ),
         (":q                     Quit", Style::default()),
     ];
 
     for (i, (text, style)) in lines.iter().enumerate() {
-        if i >= inner.height as usize { break; }
+        if i >= inner.height as usize {
+            break;
+        }
         f.render_widget(
             Paragraph::new(*text).style(*style),
-            Rect::new(inner.x + 1, inner.y + i as u16, inner.width.saturating_sub(2), 1),
+            Rect::new(
+                inner.x + 1,
+                inner.y + i as u16,
+                inner.width.saturating_sub(2),
+                1,
+            ),
         );
     }
 }