refactor: Use viewport for Analysis interactions to enable proper scrolling

internal/tui/model.go

@@ -84,6 +84,7 @@ type Model struct {
 	selectedPacketIndex int
 	flowList            list.Model
 	viewport            viewport.Model
+	analysisViewport    viewport.Model
 
 	// Packet Details View
 	detailsViewport    viewport.Model
@@ -240,9 +241,17 @@ func NewModel() Model {
 	}
 
 	// Initialize model with zero-sized viewport, will resize on WindowSizeMsg or view entry
+	// Viewport for Transaction Flow
 	vp := viewport.New(0, 0)
 	vp.YPosition = 0
 
+	// Viewport for Analysis List
+	avp := viewport.New(0, 0)
+	avp.YPosition = 0
+
+	// Viewport for Packet Details
+	dvp := viewport.New(0, 0)
+
 	return Model{
 		currentView:      ViewDashboard,
 		subView:          SubViewNone,
@@ -252,7 +261,9 @@ func NewModel() Model {
 		sshConfig:        NewSSHConfigModel(),
 		nodeInput:        createNodeInputs(),
 		viewport:         vp,
-		detailsViewport: viewport.New(0, 0),
+		analysisViewport: avp,
+		detailsViewport:  dvp,
+		fileBrowser:      NewFileBrowser(".", ".pcap"),
 		styles:           defaultStyles(),
 	}
 }
@@ -324,6 +335,8 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 			// If we are in Call Detail view, we might need to update the viewport content dynamically!
 			if m.subView == SubViewCallDetail {
 				m.updateCallDetailView()
+			} else if m.currentView == ViewAnalysis {
+				m.updateAnalysisView()
 			}
 		}
 
@@ -432,6 +445,19 @@ func (m Model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		if m.subView == SubViewCallDetail {
 			m.updateCallDetailView()
 		}
+
+		// Update Analysis Viewport size
+		// Header (Title+Counts) ~2 lines, Footer (Help) ~2 lines -> ~4 lines overhead
+		analysisHeight := m.height - 4
+		if analysisHeight < 0 {
+			analysisHeight = 0
+		}
+		m.analysisViewport.Width = m.width
+		m.analysisViewport.Height = analysisHeight
+
+		if m.currentView == ViewAnalysis {
+			m.updateAnalysisView()
+		}
 	}
 
 	return m, tea.Batch(cmds...)
@@ -485,52 +511,27 @@ func (m *Model) handleViewKeys(msg tea.KeyMsg) tea.Cmd {
 		case "up", "k":
 			if m.selectedFlow > 0 {
 				m.selectedFlow--
-				if m.selectedFlow < m.analysisOffset {
+				m.updateAnalysisView()
-					m.analysisOffset = m.selectedFlow
-				}
 			}
 		case "down", "j":
 			flows := m.callFlowStore.GetSortedFlows()
 			if m.selectedFlow < len(flows)-1 {
 				m.selectedFlow++
-				// Check if we need to scroll down
+				m.updateAnalysisView()
-				// Visible height calculation (approximate)
-				headerHeight := 4 // Title + Call count + padding
-				footerHeight := 2 // Help text
-				availableHeight := m.height - headerHeight - footerHeight
-				if availableHeight < 5 {
-					availableHeight = 5
-				}
-
-				if m.selectedFlow >= m.analysisOffset+availableHeight {
-					m.analysisOffset++
-				}
 			}
 		case "pgup":
 			m.selectedFlow -= 10
 			if m.selectedFlow < 0 {
 				m.selectedFlow = 0
 			}
-			if m.selectedFlow < m.analysisOffset {
+			m.updateAnalysisView()
-				m.analysisOffset = m.selectedFlow
-			}
 		case "pgdown":
 			flows := m.callFlowStore.GetSortedFlows()
 			m.selectedFlow += 10
 			if m.selectedFlow >= len(flows) {
 				m.selectedFlow = len(flows) - 1
 			}
-
+			m.updateAnalysisView()
-			headerHeight := 4
-			footerHeight := 2
-			availableHeight := m.height - headerHeight - footerHeight
-			if availableHeight < 5 {
-				availableHeight = 5
-			}
-
-			if m.selectedFlow >= m.analysisOffset+availableHeight {
-				m.analysisOffset = m.selectedFlow - availableHeight + 1
-			}
 		case "enter":
 			m.subView = SubViewCallDetail
 			m.updateCallDetailView()
@@ -1247,85 +1248,6 @@ func (m Model) viewCapture() string {
 	return lipgloss.JoinVertical(lipgloss.Left, title, lipgloss.JoinVertical(lipgloss.Left, lines...))
 }
 
-func (m Model) viewAnalysis() string {
-	title := m.styles.Title.Render("📊 Analysis")
-
-	flows := m.callFlowStore.GetSortedFlows()
-
-	if len(flows) == 0 {
-		return lipgloss.JoinVertical(lipgloss.Left, title,
-			"No calls captured yet.",
-			"",
-			"Start capturing on the Capture tab to see call flows here.",
-			"",
-			m.styles.Help.Render("Press 2 to go to Capture"))
-	}
-
-	var lines []string
-	// Header is handled in return statement now
-	// lines = append(lines, fmt.Sprintf("Calls: %d", len(flows)))
-	// lines = append(lines, "")
-
-	for i, flow := range flows {
-		prefix := "  "
-		style := m.styles.Inactive
-		if i == m.selectedFlow {
-			prefix = "▶ "
-			style = m.styles.Active
-		}
-
-		stateIcon := "○"
-		switch flow.State {
-		case sip.CallStateRinging:
-			stateIcon = "◐"
-		case sip.CallStateConnected:
-			stateIcon = "●"
-		case sip.CallStateTerminated:
-			stateIcon = "◯"
-		case sip.CallStateFailed:
-			stateIcon = "✕"
-		}
-
-		summary := fmt.Sprintf("%s%s %s → %s [%d pkts]",
-			prefix, stateIcon,
-			truncate(extractUser(flow.From), 15),
-			truncate(extractUser(flow.To), 15),
-			len(flow.Packets))
-
-		lines = append(lines, style.Render(summary))
-	}
-
-	// Apply Viewport/Scrolling
-	headerHeight := 4 // Title + Call count + padding
-	footerHeight := 2 // Help text
-	availableHeight := m.height - headerHeight - footerHeight
-	if availableHeight < 5 {
-		availableHeight = 5
-	}
-
-	// Sanity check offset
-	if m.analysisOffset > len(lines)-1 {
-		m.analysisOffset = len(lines) - 1
-	}
-	if m.analysisOffset < 0 {
-		m.analysisOffset = 0
-	}
-
-	end := m.analysisOffset + availableHeight
-	if end > len(lines) {
-		end = len(lines)
-	}
-
-	visibleLines := lines[m.analysisOffset:end]
-
-	return lipgloss.JoinVertical(lipgloss.Left, title,
-		fmt.Sprintf("Calls: %d (Showing %d-%d)", len(flows), m.analysisOffset+1, end),
-		"",
-		lipgloss.JoinVertical(lipgloss.Left, visibleLines...),
-		"",
-		m.styles.Help.Render("↑/↓ select • Enter details • q quit"))
-}
-
 func (m Model) viewNetworkMap() string {
 	title := m.styles.Title.Render("🗺️ Network Map")
 
@@ -1541,6 +1463,70 @@ func (m *Model) updateCallDetailView() {
 	m.viewport.SetContent(right.String())
 }
 
+func (m *Model) updateAnalysisView() {
+	flows := m.callFlowStore.GetSortedFlows()
+
+	if len(flows) == 0 {
+		m.analysisViewport.SetContent("No calls captured yet.\n\nStart capturing on the Capture tab to see call flows here.")
+		return
+	}
+
+	var lines []string
+	for i, flow := range flows {
+		prefix := "  "
+		style := m.styles.Inactive
+		if i == m.selectedFlow {
+			prefix = "> "
+			style = m.styles.Active
+		}
+
+		stateIcon := "○"
+		switch flow.State {
+		case sip.CallStateRinging:
+			stateIcon = "◐"
+		case sip.CallStateConnected:
+			stateIcon = "●"
+		case sip.CallStateTerminated:
+			stateIcon = "◯"
+		case sip.CallStateFailed:
+			stateIcon = "✕"
+		}
+
+		summary := fmt.Sprintf("%s%s %s → %s [%d pkts]",
+			prefix, stateIcon,
+			truncate(extractUser(flow.From), 15),
+			truncate(extractUser(flow.To), 15),
+			len(flow.Packets))
+
+		lines = append(lines, style.Render(summary))
+	}
+
+	m.analysisViewport.SetContent(strings.Join(lines, "\n"))
+
+	// Sync viewport scrolling
+	// Similar to transaction flow: keep selected line visible
+	if m.selectedFlow < m.analysisViewport.YOffset {
+		m.analysisViewport.SetYOffset(m.selectedFlow)
+	} else if m.selectedFlow >= m.analysisViewport.YOffset+m.analysisViewport.Height {
+		m.analysisViewport.SetYOffset(m.selectedFlow - m.analysisViewport.Height + 1)
+	}
+}
+
+func (m Model) viewAnalysis() string {
+	title := m.styles.Title.Render("📊 Analysis")
+	flows := m.callFlowStore.GetSortedFlows()
+
+	countStr := fmt.Sprintf("Calls: %d", len(flows))
+
+	return lipgloss.JoinVertical(lipgloss.Left,
+		title,
+		countStr,
+		"",
+		m.analysisViewport.View(),
+		"",
+		m.styles.Help.Render("↑/↓ select • Enter details • q quit"))
+}
+
 func (m *Model) exportCallToLog(flow *sip.CallFlow, filename string) error {
 	f, err := os.Create(filename)
 	if err != nil {