Download Functionality Feature Complete

src/main.rs

@@ -1562,7 +1562,8 @@ fn ui(frame: &mut Frame, app: &App) {
         "{connected}\n\np/P:   play/autoplay
 r/R:   resume/autoplay
 d:     download / cancel
-D:     focus downloads\nq:     quit\n/help: more help"
+q:     quit
+/help: more help"
     );
 
     frame.render_widget(
@@ -2389,82 +2390,134 @@ fn mpv_progress(st: &MpvState) -> (u16, String) {
 }
 
 fn render_downloads_panel(frame: &mut Frame, app: &App, area: Rect) {
-    // Build rows
-    let mut rows: Vec<ListItem> = Vec::new();
-
-    if let Some(dm) = &app.downloads {
-        match dm.state.lock() {
-            Ok(st) => {
-                if st.queue.is_empty() {
-                    rows.push(ListItem::new("(empty)"));
-                } else {
-                    // Fit to available height inside borders
-                    let max_rows = area.height.saturating_sub(2) as usize;
-
-                    for (i, it) in st.queue.iter().enumerate().take(max_rows) {
-                        let status = match &it.status {
-                            DownloadStatus::Queued => "queued",
-                            DownloadStatus::Downloading => "downloading",
-                            DownloadStatus::Finalizing => "finalizing",
-                            DownloadStatus::Completed => "done",
-                            DownloadStatus::Cancelled => "cancelled",
-                            DownloadStatus::Failed(_) => "failed",
-                        };
-
-                        // Always mark the active (front) item with ▶ like before
-                        let active_prefix = if i == 0 { "▶ " } else { "  " };
-
-                        // If downloading, show "NN% (ETA)" BEFORE the title
-                        let prog_prefix = if matches!(it.status, DownloadStatus::Downloading) {
-                            format_download_pct_eta(it.bytes_downloaded, it.bytes_total, it.added_at)
-                        } else {
-                            String::new()
-                        };
-
-                        rows.push(ListItem::new(format!(
-                            "{active_prefix}{status}: {prog_prefix}{}",
-                            it.title
-                        )));
-                    }
-
-                    // NOTE: intentionally removed the footer "— {msg}" line
-                    // because you said it’s unnecessary.
-                }
-            }
-            Err(_) => rows.push(ListItem::new("(downloads lock poisoned)")),
-        }
-    } else {
-        rows.push(ListItem::new("(downloads disabled)"));
-    }
-
-    // Create the list widget
     let title = if app.downloads_focus {
         "Downloads (focus)"
     } else {
         "Downloads"
     };
 
+    // rows available inside the border
+    let viewport = area.height.saturating_sub(2) as usize;
+
+    let mut rows: Vec<ListItem> = Vec::new();
+    let mut state = ListState::default();
+
+    // Helper: "basic" scrolling window (no centering)
+    // Ensures selected is always visible within [start, start+viewport)
+    fn basic_window(len: usize, selected: usize, viewport: usize) -> (usize, usize) {
+        if len == 0 || viewport == 0 {
+            return (0, 0);
+        }
+        let viewport = viewport.min(len);
+        let mut start = 0usize;
+
+        // If selected is below the visible window, scroll down just enough
+        if selected >= start + viewport {
+            start = selected + 1 - viewport;
+        }
+        // If selected is above the visible window, scroll up just enough
+        if selected < start {
+            start = selected;
+        }
+
+        // Clamp
+        if start + viewport > len {
+            start = len - viewport;
+        }
+
+        (start, start + viewport)
+    }
+
+    // Empty states
+    if app.downloads.is_none() {
+        rows.push(ListItem::new("(downloads disabled)"));
+        state.select(None);
+
+        let list = List::new(rows)
+            .block(Block::bordered().title(title).merge_borders(MergeStrategy::Exact))
+            .highlight_symbol(">> ")
+            .highlight_style(Style::default().add_modifier(Modifier::REVERSED));
+
+        frame.render_stateful_widget(list, area, &mut state);
+        return;
+    }
+
+    let dm = app.downloads.as_ref().unwrap();
+
+    match dm.state.lock() {
+        Err(_) => {
+            rows.push(ListItem::new("(downloads lock poisoned)"));
+            state.select(None);
+        }
+        Ok(st) => {
+            let len = st.queue.len();
+
+            if len == 0 {
+                rows.push(ListItem::new("(empty)"));
+                state.select(None);
+            } else {
+                // Clamp selection
+                let selected = app.downloads_selected.min(len.saturating_sub(1));
+
+                // Basic scrolling window
+                let (start, end) = basic_window(len, selected, viewport);
+
+                for i in start..end {
+                    let it = match st.queue.get(i) {
+                        Some(v) => v,
+                        None => continue,
+                    };
+
+                    let status = match &it.status {
+                        DownloadStatus::Queued => "queued",
+                        DownloadStatus::Downloading => "downloading",
+                        DownloadStatus::Finalizing => "finalizing",
+                        DownloadStatus::Completed => "done",
+                        DownloadStatus::Cancelled => "cancelled",
+                        DownloadStatus::Failed(_) => "failed",
+                    };
+
+                    let active_prefix = if i == 0 { "▶ " } else { "  " };
+
+                    // Prefer aria2-derived info if you have it; otherwise it will show --% (--:--)
+                    let prog_prefix = if matches!(it.status, DownloadStatus::Downloading) {
+                        // uses the fields you now populate from aria2 RPC
+                        // (bytes_downloaded, bytes_total, eta_secs)
+                        let pct_str = match it.bytes_total {
+                            Some(t) if t > 0 => {
+                                let pct = (it.bytes_downloaded as f64 / t as f64) * 100.0;
+                                format!("{:0.0}%", pct.clamp(0.0, 100.0))
+                            }
+                            _ => "--%".to_string(),
+                        };
+
+                        let eta_str = match it.eta_secs {
+                            Some(s) => fmt_hms(s as f64),
+                            None => "--:--".to_string(),
+                        };
+
+                        format!("{pct_str} ({eta_str}) ")
+                    } else {
+                        String::new()
+                    };
+
+                    rows.push(ListItem::new(format!(
+                        "{active_prefix}{status}: {prog_prefix}{}",
+                        it.title
+                    )));
+                }
+
+                // selection must be relative to the window slice
+                state.select(Some(selected - start));
+            }
+        }
+    }
+
     let list = List::new(rows)
         .block(Block::bordered().title(title).merge_borders(MergeStrategy::Exact))
         .highlight_symbol(">> ")
         .highlight_style(Style::default().add_modifier(Modifier::REVERSED));
 
-    let mut state = ListState::default();
-
-    // Clamp selection so it never goes out of bounds
-    let len = app
-        .downloads
-        .as_ref()
-        .and_then(|dm| dm.state.lock().ok().map(|st| st.queue.len()))
-        .unwrap_or(0);
-
-    if len == 0 {
-        state.select(None);
-    } else {
-        let sel = app.downloads_selected.min(len.saturating_sub(1));
-        state.select(Some(sel));
-    }
-
     frame.render_stateful_widget(list, area, &mut state);
 }