feat: use shift+tab to toggle selection and move up (#167)

* feat: use `shift+tab` to toggle selection and move up

* refactor: extract CursorUp, CursorDown, ToggleSelection methods

Co-authored-by: Maas Lalani <maas@lalani.dev>

filter/filter.go

@@ -119,34 +119,21 @@ func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			m.quitting = true
 			return m, tea.Quit
 		case "ctrl+n", "ctrl+j", "down":
-			m.cursor = clamp(0, len(m.matches)-1, m.cursor+1)
+			m.CursorDown()
-			if m.cursor >= m.viewport.YOffset+m.viewport.Height {
-				m.viewport.LineDown(1)
-			}
 		case "ctrl+p", "ctrl+k", "up":
-			m.cursor = clamp(0, len(m.matches)-1, m.cursor-1)
+			m.CursorUp()
-			if m.cursor < m.viewport.YOffset {
-				m.viewport.SetYOffset(m.cursor)
-			}
 		case "tab":
 			if m.limit == 1 {
 				break // no op
 			}
-
+			m.ToggleSelection()
-			// Tab is used to toggle selection of current item in the list
+			m.CursorDown()
-			if _, ok := m.selected[m.matches[m.cursor].Str]; ok {
+		case "shift+tab":
-				delete(m.selected, m.matches[m.cursor].Str)
+			if m.limit == 1 {
-				m.numSelected--
+				break // no op
-			} else if m.numSelected < m.limit {
-				m.selected[m.matches[m.cursor].Str] = struct{}{}
-				m.numSelected++
-			}
-
-			// Go down by one line
-			m.cursor = clamp(0, len(m.matches)-1, m.cursor+1)
-			if m.cursor >= m.viewport.YOffset+m.viewport.Height {
-				m.viewport.LineDown(1)
 			}
+			m.ToggleSelection()
+			m.CursorUp()
 		default:
 			m.textinput, cmd = m.textinput.Update(msg)
 
@@ -170,6 +157,30 @@ func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 	return m, cmd
 }
 
+func (m *model) CursorUp() {
+	m.cursor = clamp(0, len(m.matches)-1, m.cursor-1)
+	if m.cursor < m.viewport.YOffset {
+		m.viewport.SetYOffset(m.cursor)
+	}
+}
+
+func (m *model) CursorDown() {
+	m.cursor = clamp(0, len(m.matches)-1, m.cursor+1)
+	if m.cursor >= m.viewport.YOffset+m.viewport.Height {
+		m.viewport.LineDown(1)
+	}
+}
+
+func (m *model) ToggleSelection() {
+	if _, ok := m.selected[m.matches[m.cursor].Str]; ok {
+		delete(m.selected, m.matches[m.cursor].Str)
+		m.numSelected--
+	} else if m.numSelected < m.limit {
+		m.selected[m.matches[m.cursor].Str] = struct{}{}
+		m.numSelected++
+	}
+}
+
 func matchAll(options []string) []fuzzy.Match {
 	var matches = make([]fuzzy.Match, len(options))
 	for i, option := range options {