Introduce central theme module; rounded borders and consistent styling

All colors/styles now live in src/theme.rs (palette + pane/dialog
block builders): sidebar, file view, bottom bar, context menu and all
dialogs share one look that can be changed in one place. Rounded
borders throughout.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

src/main.rs

@@ -1,6 +1,7 @@
 mod app;
 mod config;
 mod file_ops;
+mod theme;
 mod ui;
 mod events;
 

src/theme.rs

@@ -0,0 +1,95 @@
+//! Centralt tema för TUI-FM.
+//!
+//! ALLA färger och återkommande stilar definieras här — ändra utseendet
+//! på hela appen från en enda fil. UI-koden ska aldrig hårdkoda
+//! `Color::`-literaler för sådant som temat täcker.
+//!
+//! OBS: använd bara tecken med entydig bredd i UI:t — se
+//! `file_ops::tests::emoji_icons_are_wide`.
+
+use ratatui::style::{Color, Modifier, Style};
+use ratatui::widgets::{Block, BorderType, Borders};
+
+// ─── Palett ──────────────────────────────────────────────────────────────
+/// Fokusmarkering och markerade rader
+pub const ACCENT: Color = Color::Cyan;
+/// Rubriker och interaktiva knappar
+pub const HEADER: Color = Color::Yellow;
+/// Navigering ("Gå upp" m.m.)
+pub const NAV: Color = Color::Magenta;
+/// Positiv handling (skapa, lägg till)
+pub const OK: Color = Color::Green;
+/// Destruktiv handling (ta bort, stäng)
+pub const DANGER: Color = Color::Red;
+/// Nedtonad text: hints, avgränsare, ofokuserade ramar
+pub const DIM: Color = Color::DarkGray;
+/// Normal text
+pub const TEXT: Color = Color::White;
+
+// ─── Stilar ──────────────────────────────────────────────────────────────
+pub fn header() -> Style {
+    Style::default().fg(HEADER).add_modifier(Modifier::BOLD)
+}
+
+pub fn nav() -> Style {
+    Style::default().fg(NAV).add_modifier(Modifier::BOLD)
+}
+
+pub fn hint() -> Style {
+    Style::default().fg(DIM)
+}
+
+pub fn button() -> Style {
+    Style::default().fg(OK).add_modifier(Modifier::BOLD)
+}
+
+pub fn selected_row() -> Style {
+    Style::default()
+        .fg(Color::Black)
+        .bg(ACCENT)
+        .add_modifier(Modifier::BOLD)
+}
+
+pub fn current_item() -> Style {
+    Style::default().fg(ACCENT).add_modifier(Modifier::BOLD)
+}
+
+pub fn text() -> Style {
+    Style::default().fg(TEXT)
+}
+
+// ─── Block/ramar ─────────────────────────────────────────────────────────
+/// Standardram för en yta: rundade hörn, accentfärg vid fokus.
+pub fn pane_block(title: &str, focused: bool) -> Block<'static> {
+    let border = if focused {
+        Style::default().fg(ACCENT)
+    } else {
+        Style::default().fg(DIM)
+    };
+    let block = Block::default()
+        .borders(Borders::ALL)
+        .border_type(BorderType::Rounded)
+        .border_style(border);
+    if title.is_empty() {
+        block
+    } else {
+        block
+            .title(format!(" {} ", title))
+            .title_style(Style::default().fg(TEXT).add_modifier(Modifier::BOLD))
+    }
+}
+
+/// Ram för dialoger/popups: rundade hörn, färgad ram + rubrik.
+pub fn dialog_block_colored(title: &str, color: Color) -> Block<'static> {
+    Block::default()
+        .title(format!(" {} ", title))
+        .title_style(Style::default().fg(color).add_modifier(Modifier::BOLD))
+        .borders(Borders::ALL)
+        .border_type(BorderType::Rounded)
+        .border_style(Style::default().fg(color))
+}
+
+/// Standarddialog: accentfärgad.
+pub fn dialog_block(title: &str) -> Block<'static> {
+    dialog_block_colored(title, ACCENT)
+}

src/ui.rs

@@ -12,6 +12,7 @@ use ratatui::{
 use unicode_width::UnicodeWidthStr;
 
 use crate::app::{App, ContextMenuItem, DialogMode, Focus};
+use crate::theme;
 use crate::file_ops::{self, format_size};
 
 /// Compute the display width of a string, accounting for emojis (2 columns) and
@@ -124,24 +125,15 @@ pub fn draw(f: &mut Frame, app: &mut App) {
 
 fn draw_sidebar(f: &mut Frame, app: &App, area: Rect) {
     let focused = app.focus == Focus::Sidebar;
-    let border_style = if focused {
+    let block = theme::pane_block("Navigering", focused);
-        Style::default().fg(Color::Cyan)
-    } else {
-        Style::default().fg(Color::DarkGray)
-    };
-
-    let block = Block::default()
-        .title(" Navigering ")
-        .borders(Borders::ALL)
-        .border_style(border_style);
 
     let inner = block.inner(area);
     f.render_widget(block, area);
 
-    let header_s = Style::default().fg(Color::Yellow).add_modifier(Modifier::BOLD);
+    let header_s = theme::header();
-    let go_up_s  = Style::default().fg(Color::Magenta).add_modifier(Modifier::BOLD);
+    let go_up_s  = theme::nav();
-    let hint_s   = Style::default().fg(Color::DarkGray);
+    let hint_s   = theme::hint();
-    let btn_s    = Style::default().fg(Color::Green).add_modifier(Modifier::BOLD);
+    let btn_s    = theme::button();
 
     let sep_str: String = if app.unicode_support {
         "\u{2500}".repeat(inner.width as usize)
@@ -187,11 +179,7 @@ fn draw_sidebar(f: &mut Frame, app: &App, area: Rect) {
                 .map(|n| n.to_string_lossy().to_string())
                 .unwrap_or_else(|| fav.clone());
             let is_current = fav == &app.current_path.to_string_lossy().to_string();
-            let style = if is_current {
+            let style = if is_current { theme::current_item() } else { theme::text() };
-                Style::default().fg(Color::Cyan).add_modifier(Modifier::BOLD)
-            } else {
-                Style::default().fg(Color::White)
-            };
             // ★ U+2605 is East-Asian-Width Narrow → 1 display column, safe for alignment
             let star = if app.unicode_support { "\u{2605}" } else { "*" };
             let icon_w = display_width(star);
@@ -286,11 +274,6 @@ fn draw_sidebar(f: &mut Frame, app: &App, area: Rect) {
 
 fn draw_file_view(f: &mut Frame, app: &App, area: Rect) {
     let focused = app.focus == Focus::FileView;
-    let border_style = if focused {
-        Style::default().fg(Color::Cyan)
-    } else {
-        Style::default().fg(Color::DarkGray)
-    };
 
     let rows: Vec<Row> = app
         .entries
@@ -327,14 +310,11 @@ fn draw_file_view(f: &mut Frame, app: &App, area: Rect) {
         Cell::from("Namn"),
         Cell::from("Storlek"),
     ])
-    .style(Style::default().fg(Color::Yellow).add_modifier(Modifier::BOLD | Modifier::UNDERLINED))
+    .style(theme::header().add_modifier(Modifier::UNDERLINED))
     .height(1);
 
-    let path_title = format!(" {} ", app.current_path.to_string_lossy());
+    let path_title = app.current_path.to_string_lossy();
-    let block = Block::default()
+    let block = theme::pane_block(&path_title, focused);
-        .title(path_title)
-        .borders(Borders::ALL)
-        .border_style(border_style);
 
     let widths = [Constraint::Min(10), Constraint::Length(10)];
 
@@ -386,13 +366,7 @@ fn draw_file_view(f: &mut Frame, app: &App, area: Rect) {
 fn draw_bottom_bar(f: &mut Frame, app: &App, area: Rect) {
     let focused = app.focus == Focus::PathInput;
 
-    let outer_block = Block::default()
+    let outer_block = theme::pane_block("", focused);
-        .borders(Borders::ALL)
-        .border_style(if focused {
-            Style::default().fg(Color::Cyan)
-        } else {
-            Style::default().fg(Color::DarkGray)
-        });
 
     let inner = outer_block.inner(area);
     f.render_widget(outer_block, area);
@@ -544,10 +518,7 @@ fn draw_context_menu(f: &mut Frame, app: &App, menu: crate::app::ContextMenu) {
     let menu_area = Rect::new(x, y, menu_width, menu_height);
     f.render_widget(Clear, menu_area);
 
-    let block = Block::default()
+    let block = theme::dialog_block("Meny");
-        .title(" Meny ")
-        .borders(Borders::ALL)
-        .border_style(Style::default().fg(Color::Cyan));
 
     let inner = block.inner(menu_area);
     f.render_widget(block, menu_area);
@@ -625,9 +596,7 @@ fn draw_context_menu(f: &mut Frame, app: &App, menu: crate::app::ContextMenu) {
         let sub_x = (x + menu_width).min(term_area.width.saturating_sub(sub_w));
         let sub_area = Rect::new(sub_x, new_sub_row, sub_w, 4);
         f.render_widget(Clear, sub_area);
-        let sub_block = Block::default()
+        let sub_block = theme::dialog_block_colored("", theme::OK);
-            .borders(Borders::ALL)
-            .border_style(Style::default().fg(Color::Green));
         let sub_inner = sub_block.inner(sub_area);
         f.render_widget(sub_block, sub_area);
 
@@ -678,11 +647,7 @@ fn draw_settings(f: &mut Frame, app: &App, right_edge: u16) {
     } else {
         " [S] Inställningar "
     };
-    let block = Block::default()
+    let block = theme::dialog_block_colored(title.trim(), theme::HEADER);
-        .title(title)
-        .title_style(Style::default().fg(Color::Yellow).add_modifier(Modifier::BOLD))
-        .borders(Borders::ALL)
-        .border_style(Style::default().fg(Color::Yellow));
     let inner = block.inner(area);
     f.render_widget(block, area);
 
@@ -903,10 +868,7 @@ fn draw_input_dialog(f: &mut Frame, title: &str, current: &str, area: Rect) {
     let dlg = Rect::new(x, y, dlg_width, dlg_height);
 
     f.render_widget(Clear, dlg);
-    let block = Block::default()
+    let block = theme::dialog_block(title);
-        .title(format!(" {} ", title))
-        .borders(Borders::ALL)
-        .border_style(Style::default().fg(Color::Cyan));
     let inner = block.inner(dlg);
     f.render_widget(block, dlg);
 
@@ -944,10 +906,7 @@ fn draw_properties(f: &mut Frame, info: crate::app::PropertiesInfo, area: Rect)
     let dlg = Rect::new(x, y, dlg_width, dlg_height);
 
     f.render_widget(Clear, dlg);
-    let block = Block::default()
+    let block = theme::dialog_block("Egenskaper");
-        .title(" Egenskaper ")
-        .borders(Borders::ALL)
-        .border_style(Style::default().fg(Color::Cyan));
     let inner = block.inner(dlg);
     f.render_widget(block, dlg);
 
@@ -1005,11 +964,7 @@ fn draw_error_dialog(f: &mut Frame, msg: &str, area: Rect) {
     let dlg = Rect::new(x, y, dlg_width, dlg_height);
 
     f.render_widget(Clear, dlg);
-    let block = Block::default()
+    let block = theme::dialog_block_colored("Fel", theme::DANGER);
-        .title(" Fel ")
-        .title_style(Style::default().fg(Color::Red).add_modifier(Modifier::BOLD))
-        .borders(Borders::ALL)
-        .border_style(Style::default().fg(Color::Red));
     let inner = block.inner(dlg);
     f.render_widget(block, dlg);
 
@@ -1044,11 +999,7 @@ fn draw_confirm_dialog(f: &mut Frame, msg: &str, area: Rect) {
     let dlg = Rect::new(x, y, dlg_width, dlg_height);
 
     f.render_widget(Clear, dlg);
-    let block = Block::default()
+    let block = theme::dialog_block_colored("Bekräfta", theme::HEADER);
-        .title(" Bekräfta ")
-        .title_style(Style::default().fg(Color::Yellow).add_modifier(Modifier::BOLD))
-        .borders(Borders::ALL)
-        .border_style(Style::default().fg(Color::Yellow));
     let inner = block.inner(dlg);
     f.render_widget(block, dlg);