Add more keybinding options to pager

pager/pager.go

@@ -28,6 +28,10 @@ type Model struct {
 	InactiveDot      string
 	ArabicFormat     string
 	RTL              bool
+	UseLeftRightKeys bool
+	UseUpDownKeys    bool
+	UseHLKeys        bool
+	UseJKKeys        bool
 }
 
 // SetTotalPages is a helper method for calculatng the total number of pages
@@ -45,6 +49,18 @@ func (m *Model) SetTotalPages(items int) int {
 	return n
 }
 
+func (m *Model) prevPage() {
+	if m.Page > 0 {
+		m.Page--
+	}
+}
+
+func (m *Model) nextPage() {
+	if m.Page < m.TotalPages-1 {
+		m.Page++
+	}
+}
+
 // NewModel creates a new model with defaults
 func NewModel() Model {
 	return Model{
@@ -55,28 +71,51 @@ func NewModel() Model {
 		InactiveDot:      "○",
 		ArabicFormat:     "%d/%d",
 		RTL:              false,
+		UseLeftRightKeys: true,
+		UseUpDownKeys:    false,
+		UseHLKeys:        true,
+		UseJKKeys:        false,
 	}
 }
 
 // Update is the Tea update function which binds keystrokes to pagination
-func Update(msg tea.Msg, model tea.Model) (tea.Model, tea.Cmd) {
-	m, ok := model.(Model)
-	if !ok {
-		return tea.ModelAssertionErr, nil
-	}
+func Update(msg tea.Msg, m Model) (Model, tea.Cmd) {
 	switch msg := msg.(type) {
 	case tea.KeyMsg:
+		if m.UseLeftRightKeys {
 			switch msg.String() {
 			case "left":
-			if m.Page > 0 {
-				m.Page--
-			}
+				m.prevPage()
 			case "right":
-			if m.Page < m.TotalPages-1 {
-				m.Page++
+				m.nextPage()
+			}
+		}
+		if m.UseUpDownKeys {
+			switch msg.String() {
+			case "up":
+				m.prevPage()
+			case "down":
+				m.nextPage()
+			}
+		}
+		if m.UseHLKeys {
+			switch msg.String() {
+			case "h":
+				m.prevPage()
+			case "l":
+				m.nextPage()
+			}
+		}
+		if m.UseJKKeys {
+			switch msg.String() {
+			case "j":
+				m.prevPage()
+			case "k":
+				m.nextPage()
 			}
 		}
 	}
+
 	return m, nil
 }