tui: fleshed out converation selection

pkg/tui/chat.go

@@ -253,6 +253,7 @@ func (m chatModel) Update(msg tea.Msg) (chatModel, tea.Cmd) {
 		m.conversation = (*models.Conversation)(msg)
 		cmds = append(cmds, m.loadMessages(m.conversation))
 	case msgMessagesLoaded:
+		m.selectedMessage = len(msg) - 1
 		m.setMessages(msg)
 		m.updateContent()
 		m.content.GotoBottom()
@@ -407,7 +408,7 @@ func (m *chatModel) handleMessagesKey(msg tea.KeyMsg) (bool, tea.Cmd) {
 			m.selectedMessage--
 			m.updateContent()
 			offset := m.messageOffsets[m.selectedMessage]
-			scrollIntoView(&m.content, offset, 0.1)
+			scrollIntoView(&m.content, offset, m.content.Height/2)
 		}
 		return true, nil
 	case "ctrl+j":
@@ -415,7 +416,7 @@ func (m *chatModel) handleMessagesKey(msg tea.KeyMsg) (bool, tea.Cmd) {
 			m.selectedMessage++
 			m.updateContent()
 			offset := m.messageOffsets[m.selectedMessage]
-			scrollIntoView(&m.content, offset, 0.1)
+			scrollIntoView(&m.content, offset, m.content.Height/2)
 		}
 		return true, nil
 	case "ctrl+r":
@@ -441,7 +442,7 @@ func (m *chatModel) handleInputKey(msg tea.KeyMsg) (bool, tea.Cmd) {
 				m.selectedMessage = len(m.messages) - 1
 			}
 			offset := m.messageOffsets[m.selectedMessage]
-			scrollIntoView(&m.content, offset, 0.1)
+			scrollIntoView(&m.content, offset, m.content.Height/2)
 		}
 		m.updateContent()
 		m.input.Blur()

pkg/tui/conversations.go

@@ -29,7 +29,8 @@ type conversationsModel struct {
 	basemodel
 
 	conversations []loadedConversation
-	cursor        int // index of the currently selected message message
+	cursor        int   // index of the currently selected conversation
+	itemOffsets   []int // keeps track of the viewport y offset of each rendered item
 
 	content viewport.Model
 }
@@ -59,13 +60,33 @@ func (m *conversationsModel) handleInput(msg tea.KeyMsg) (bool, tea.Cmd) {
 	case "j", "down":
 		if m.cursor < len(m.conversations)-1 {
 			m.cursor++
+			if m.cursor == len(m.conversations)-1 {
+				// if last conversation, simply scroll to the bottom
+				m.content.GotoBottom()
+			} else {
+				// this hack positions the *next* conversatoin slightly
+				// *off* the screen, ensuring the entire m.cursor is shown,
+				// even if its height may not be constant due to wrapping.
+				scrollIntoView(&m.content, m.itemOffsets[m.cursor+1], -1)
+			}
 			m.content.SetContent(m.renderConversationList())
+		} else {
+			m.cursor = len(m.conversations) - 1
+			m.content.GotoBottom()
 		}
 		return true, nil
 	case "k", "up":
 		if m.cursor > 0 {
 			m.cursor--
+			if m.cursor == 0 {
+				m.content.GotoTop()
+			} else {
+				scrollIntoView(&m.content, m.itemOffsets[m.cursor], 1)
+			}
 			m.content.SetContent(m.renderConversationList())
+		} else {
+			m.cursor = 0
+			m.content.GotoTop()
 		}
 		return true, nil
 	case "n":
@@ -186,7 +207,6 @@ func (m *conversationsModel) renderConversationList() string {
 		{"Older", now.Sub(time.Time{})},
 	}
 
-	// TODO: pick nice color
 	categoryStyle := lipgloss.NewStyle().
 		MarginBottom(1).
 		Foreground(lipgloss.Color("170")).
@@ -201,8 +221,12 @@ func (m *conversationsModel) renderConversationList() string {
 	untitledStyle := lipgloss.NewStyle().Faint(true).Italic(true)
 	selectedStyle := lipgloss.NewStyle().Faint(true).Foreground(lipgloss.Color("6"))
 
+	var currentOffset int
 	var currentCategory string
+	m.itemOffsets = make([]int, len(m.conversations))
 	sb := &strings.Builder{}
+	sb.WriteRune('\n')
+	currentOffset += 1
 	for i, c := range m.conversations {
 		lastReplyAge := now.Sub(c.lastReply.CreatedAt)
 
@@ -217,7 +241,10 @@ func (m *conversationsModel) renderConversationList() string {
 		// print the category
 		if category != currentCategory {
 			currentCategory = category
-			fmt.Fprintf(sb, "%s\n", categoryStyle.Render(currentCategory))
+			heading := categoryStyle.Render(currentCategory)
+			sb.WriteString(heading)
+			currentOffset += height(heading)
+			sb.WriteRune('\n')
 		}
 
 		tStyle := titleStyle.Copy()
@@ -234,13 +261,17 @@ func (m *conversationsModel) renderConversationList() string {
 			title = ">" + title[1:]
 		}
 
-		heading := fmt.Sprintf(
+		m.itemOffsets[i] = currentOffset
+		item := itemStyle.Render(fmt.Sprintf(
 			"%s\n%s",
 			title,
-			padding + ageStyle.Render(util.HumanTimeElapsedSince(lastReplyAge)),
+			padding+ageStyle.Render(util.HumanTimeElapsedSince(lastReplyAge)),
-		)
+		))
-		sb.WriteString(itemStyle.Render(heading))
+		sb.WriteString(item)
+		currentOffset += height(item)
+		if i < len(m.conversations)-1 {
 			sb.WriteRune('\n')
 		}
+	}
 	return sb.String()
 }

pkg/tui/util.go

@@ -73,7 +73,7 @@ func truncateToCellWidth(str string, width int, tail string) string {
 // fraction is the fraction of the total screen height into view the offset
 // should be scrolled into view. 0.5 = items will be snapped to middle of
 // view
-func scrollIntoView(vp *viewport.Model, offset int, fraction float32) {
+func scrollIntoView(vp *viewport.Model, offset int, edge int) {
 	currentOffset := vp.YOffset
 	if offset >= currentOffset && offset < currentOffset+vp.Height {
 		return
@@ -81,9 +81,9 @@ func scrollIntoView(vp *viewport.Model, offset int, fraction float32) {
 	distance := currentOffset - offset
 	if distance < 0 {
 		// we should scroll down until it just comes into view
-		vp.SetYOffset(currentOffset - (distance + (vp.Height - int(float32(vp.Height)*fraction))) + 1)
+		vp.SetYOffset(currentOffset - (distance + (vp.Height - edge)) + 1)
 	} else {
 		// we should scroll up
-		vp.SetYOffset(currentOffset - distance - int(float32(vp.Height)*fraction))
+		vp.SetYOffset(currentOffset - distance - edge)
 	}
 }