Library: keep the place after removing a title

The list is reloaded after a removal and the selection follows the
selected title by id; the removed title is gone, so it fell back to the
top. Now a title that has left the library hands its row to the one that
moved up into it (or the new last one). A title that is only filtered out
still starts the list from the top.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_019reK4DUGYqDUjniWYJvwUW

internal/ui/library.go

@@ -391,9 +391,9 @@ func (v *libraryView) render() {
 }
 
 func (v *libraryView) renderPane(p *libPane) {
-	selID := -1
+	selID, prevRow := -1, 0
 	if r, _ := p.table.GetSelection(); r >= 1 && r <= len(p.shown) {
-		selID = p.shown[r-1].id
+		selID, prevRow = p.shown[r-1].id, r
 	}
 	p.shown = filterItems(p.all, p.filter, p.text, p.attr)
 
@@ -408,6 +408,13 @@ func (v *libraryView) renderPane(p *libPane) {
 			selRow = i + 1
 		}
 	}
+	if selRow == 0 && selID != -1 && !containsItem(p.all, selID) {
+		// The selected title is gone from the library (removed): stay at its
+		// place, on the title that moved up into it (or the new last one),
+		// instead of jumping to the top. A title that is only filtered out
+		// still starts the list from the top.
+		selRow = min(prevRow, len(p.shown))
+	}
 	placeholder := "Nothing matches the filter"
 	switch {
 	case p.err != nil && !p.loaded:
@@ -437,6 +444,15 @@ func (v *libraryView) renderPane(p *libPane) {
 	p.table.SetTitle(title + " ")
 }
 
+func containsItem(items []libItem, id int) bool {
+	for _, it := range items {
+		if it.id == id {
+			return true
+		}
+	}
+	return false
+}
+
 func (v *libraryView) renderDetails() {
 	if it, ok := v.selected(); ok {
 		v.details.Show(it.details, it.cover)

internal/ui/library_test.go

@@ -209,3 +209,51 @@ func TestListedValues(t *testing.T) {
 		t.Errorf("empty pool: %v", got)
 	}
 }
+
+func TestRemovingATitleKeepsThePlace(t *testing.T) {
+	a := newTestApp(t)
+	v := newLibraryView(a, a.radarr, a.sonarr)
+	p := v.panes[0]
+	items := func(ids ...int) []libItem {
+		var out []libItem
+		for _, id := range ids {
+			out = append(out, libItem{id: id, title: string(rune('A' + id)), label: string(rune('A' + id))})
+		}
+		return out
+	}
+	selectedID := func() int {
+		r, _ := p.table.GetSelection()
+		return p.shown[r-1].id
+	}
+	p.all, p.loaded = items(1, 2, 3, 4, 5), true
+	v.renderPane(p)
+
+	// Remove the third title: the fourth moves up into its place and is selected.
+	p.table.Select(3, 0)
+	p.all = items(1, 2, 4, 5)
+	v.renderPane(p)
+	if r, _ := p.table.GetSelection(); r != 3 || selectedID() != 4 {
+		t.Errorf("after removing the third: row %d, title %d", r, selectedID())
+	}
+	// Remove the last title: the new last one is selected.
+	p.table.Select(4, 0)
+	p.all = items(1, 2, 4)
+	v.renderPane(p)
+	if r, _ := p.table.GetSelection(); r != 3 || selectedID() != 4 {
+		t.Errorf("after removing the last: row %d, title %d", r, selectedID())
+	}
+	// A reload that keeps the title keeps it selected, wherever it is now.
+	p.table.Select(2, 0) // title 2
+	p.all = items(0, 1, 2, 4)
+	v.renderPane(p)
+	if selectedID() != 2 {
+		t.Errorf("kept title not followed: %d", selectedID())
+	}
+	// A title that is only filtered out still starts the list from the top.
+	p.table.Select(4, 0) // title 4
+	p.text = "B"         // title 1 only: 4 is filtered out, not removed
+	v.renderPane(p)
+	if r, _ := p.table.GetSelection(); r != 1 {
+		t.Errorf("filtered out: row %d, want the top", r)
+	}
+}