Initial commit — ferrosonic terminal Subsonic client

Terminal-based Subsonic music client in Rust featuring bit-perfect audio
playback via PipeWire sample rate switching, gapless playback, MPRIS2
desktop integration, cava audio visualizer with theme-matched gradients,
13 built-in color themes with custom TOML theme support, mouse controls,
artist/album browser, playlist support, and play queue management.

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/ui/layout.rs

@@ -0,0 +1,112 @@
+//! Main layout and rendering
+
+use ratatui::{
+    layout::{Constraint, Layout},
+    Frame,
+};
+
+use crate::app::state::{AppState, LayoutAreas, Page};
+
+use super::footer::Footer;
+use super::header::Header;
+use super::pages;
+use super::widgets::{CavaWidget, NowPlayingWidget};
+
+/// Draw the entire UI
+pub fn draw(frame: &mut Frame, state: &mut AppState) {
+    let area = frame.area();
+
+    let cava_active = state.settings_state.cava_enabled && !state.cava_screen.is_empty();
+
+    // Main layout:
+    // [Header]          - 1 line
+    // [Cava]            - ~40% (optional, only when cava is active)
+    // [Page Content]    - flexible
+    // [Now Playing]     - 7 lines
+    // [Footer]          - 1 line
+
+    let (header_area, cava_area, content_area, now_playing_area, footer_area) = if cava_active {
+        let chunks = Layout::vertical([
+            Constraint::Length(1),    // Header
+            Constraint::Percentage(40), // Cava visualizer — top half-ish
+            Constraint::Min(10),      // Page content
+            Constraint::Length(7),    // Now playing
+            Constraint::Length(1),    // Footer
+        ])
+        .split(area);
+        (chunks[0], Some(chunks[1]), chunks[2], chunks[3], chunks[4])
+    } else {
+        let chunks = Layout::vertical([
+            Constraint::Length(1),  // Header
+            Constraint::Min(10),   // Page content
+            Constraint::Length(7), // Now playing
+            Constraint::Length(1), // Footer
+        ])
+        .split(area);
+        (chunks[0], None, chunks[1], chunks[2], chunks[3])
+    };
+
+    // Compute dual-pane splits for pages that use them
+    let (content_left, content_right) = match state.page {
+        Page::Artists | Page::Playlists => {
+            let panes = Layout::horizontal([
+                Constraint::Percentage(40),
+                Constraint::Percentage(60),
+            ])
+            .split(content_area);
+            (Some(panes[0]), Some(panes[1]))
+        }
+        _ => (None, None),
+    };
+
+    // Store layout areas for mouse hit-testing
+    state.layout = LayoutAreas {
+        header: header_area,
+        cava: cava_area,
+        content: content_area,
+        now_playing: now_playing_area,
+        footer: footer_area,
+        content_left,
+        content_right,
+    };
+
+    // Render header
+    let colors = *state.settings_state.theme_colors();
+    let header = Header::new(state.page, state.now_playing.state, colors);
+    frame.render_widget(header, header_area);
+
+    // Render cava visualizer if active
+    if let Some(cava_rect) = cava_area {
+        let cava_widget = CavaWidget::new(&state.cava_screen);
+        frame.render_widget(cava_widget, cava_rect);
+    }
+
+    // Render current page
+    match state.page {
+        Page::Artists => {
+            pages::artists::render(frame, content_area, state);
+        }
+        Page::Queue => {
+            pages::queue::render(frame, content_area, state);
+        }
+        Page::Playlists => {
+            pages::playlists::render(frame, content_area, state);
+        }
+        Page::Server => {
+            pages::server::render(frame, content_area, state);
+        }
+        Page::Settings => {
+            pages::settings::render(frame, content_area, state);
+        }
+    }
+
+    // Render now playing
+    let now_playing = NowPlayingWidget::new(&state.now_playing, colors);
+    frame.render_widget(now_playing, now_playing_area);
+
+    // Render footer
+    let footer = Footer::new(state.page, colors)
+        .sample_rate(state.now_playing.sample_rate)
+        .notification(state.notification.as_ref());
+    frame.render_widget(footer, footer_area);
+}