Add WireGuard TUI implementation

- Add Go TUI with bubbletea for WireGuard management
- Implement client CRUD operations with QR code generation
- Add configuration and validation modules
- Install/update scripts for client setup
- Update Makefile to build binaries to bin/ directory
- Add .gitignore for Go projects

internal/tui/screens/list.go

@@ -0,0 +1,324 @@
+package screens
+
+import (
+	"sort"
+	"strings"
+
+	"github.com/calmcacil/wg-admin/internal/tui/components"
+	"github.com/calmcacil/wg-admin/internal/wireguard"
+	"github.com/charmbracelet/bubbles/table"
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/charmbracelet/lipgloss"
+)
+
+const statusRefreshInterval = 10 // seconds
+
+// ListScreen displays a table of WireGuard clients
+type ListScreen struct {
+	table     table.Model
+	search    *components.SearchModel
+	clients   []ClientWithStatus
+	filtered  []ClientWithStatus
+	sortedBy  string // Column name being sorted by
+	ascending bool   // Sort direction
+}
+
+// ClientWithStatus wraps a client with its connection status
+type ClientWithStatus struct {
+	Client wireguard.Client
+	Status string
+}
+
+// NewListScreen creates a new list screen
+func NewListScreen() *ListScreen {
+	return &ListScreen{
+		search:    components.NewSearch(),
+		sortedBy:  "Name",
+		ascending: true,
+	}
+}
+
+// Init initializes the list screen
+func (s *ListScreen) Init() tea.Cmd {
+	return tea.Batch(
+		s.loadClients,
+		wireguard.Tick(statusRefreshInterval),
+	)
+}
+
+// Update handles messages for the list screen
+func (s *ListScreen) Update(msg tea.Msg) (Screen, tea.Cmd) {
+	var cmd tea.Cmd
+
+	switch msg := msg.(type) {
+	case tea.KeyMsg:
+		// Handle search activation
+		if msg.String() == "/" && !s.search.IsActive() {
+			s.search.Activate()
+			return s, nil
+		}
+
+		// If search is active, pass input to search
+		if s.search.IsActive() {
+			s.search, cmd = s.search.Update(msg)
+			// Apply filter to clients
+			s.applyFilter()
+			return s, cmd
+		}
+
+		// Normal key handling when search is not active
+		switch msg.String() {
+		case "q", "ctrl+c":
+			// Handle quit in parent model
+			return s, nil
+		case "r":
+			// Refresh clients
+			return s, s.loadClients
+		case "R":
+			// Show restore screen
+			return NewRestoreScreen(), nil
+		case "Q":
+			// Show QR code for selected client
+			if len(s.table.Rows()) > 0 {
+				selected := s.table.SelectedRow()
+				clientName := selected[0] // First column is Name
+				return NewQRScreen(clientName), nil
+			}
+		case "enter":
+			// Open detail view for selected client
+			if len(s.table.Rows()) > 0 {
+				selectedRow := s.table.SelectedRow()
+				selectedName := selectedRow[0] // First column is Name
+				// Find the client with this name
+				for _, cws := range s.clients {
+					if cws.Client.Name == selectedName {
+						return s, func() tea.Msg {
+							return ClientSelectedMsg{Client: cws}
+						}
+					}
+				}
+			}
+		case "1", "2", "3", "4":
+			// Sort by column number (Name, IPv4, IPv6, Status)
+			s.sortByColumn(msg.String())
+		}
+	case clientsLoadedMsg:
+		s.clients = msg.clients
+		s.search.SetTotalCount(len(s.clients))
+		s.applyFilter()
+	case wireguard.StatusTickMsg:
+		// Refresh status on periodic tick
+		return s, s.loadClients
+	case wireguard.RefreshStatusMsg:
+		// Refresh status on manual refresh
+		return s, s.loadClients
+	}
+
+	s.table, cmd = s.table.Update(msg)
+	return s, cmd
+}
+
+// View renders the list screen
+func (s *ListScreen) View() string {
+	if len(s.clients) == 0 {
+		return s.search.View() + "\n" + "No clients found. Press 'r' to refresh or 'q' to quit."
+	}
+
+	// Check if there are no matches
+	if s.search.IsActive() && len(s.filtered) == 0 && s.search.GetQuery() != "" {
+		return s.search.View() + "\n" + lipgloss.NewStyle().
+			Foreground(lipgloss.Color("241")).
+			Italic(true).
+			Render("No matching clients found. Try a different search term.")
+	}
+
+	return s.search.View() + "\n" + s.table.View()
+}
+
+// loadClients loads clients from wireguard config
+func (s *ListScreen) loadClients() tea.Msg {
+	clients, err := wireguard.ListClients()
+	if err != nil {
+		return errMsg{err: err}
+	}
+
+	// Get status for each client
+	clientsWithStatus := make([]ClientWithStatus, len(clients))
+	for i, client := range clients {
+		status, err := wireguard.GetClientStatus(client.PublicKey)
+		if err != nil {
+			status = wireguard.StatusDisconnected
+		}
+		clientsWithStatus[i] = ClientWithStatus{
+			Client: client,
+			Status: status,
+		}
+	}
+
+	return clientsLoadedMsg{clients: clientsWithStatus}
+}
+
+// applyFilter applies the current search filter to clients
+func (s *ListScreen) applyFilter() {
+	// Convert clients to ClientData for filtering
+	clientData := make([]components.ClientData, len(s.clients))
+	for i, cws := range s.clients {
+		clientData[i] = components.ClientData{
+			Name:   cws.Client.Name,
+			IPv4:   cws.Client.IPv4,
+			IPv6:   cws.Client.IPv6,
+			Status: cws.Status,
+		}
+	}
+
+	// Filter clients
+	filteredData := s.search.Filter(clientData)
+
+	// Convert back to ClientWithStatus
+	s.filtered = make([]ClientWithStatus, len(filteredData))
+	for i, cd := range filteredData {
+		// Find the matching client
+		for _, cws := range s.clients {
+			if cws.Client.Name == cd.Name {
+				s.filtered[i] = cws
+				break
+			}
+		}
+	}
+
+	// Rebuild table with filtered clients
+	s.buildTable()
+}
+
+// buildTable creates and configures the table
+func (s *ListScreen) buildTable() {
+	columns := []table.Column{
+		{Title: "Name", Width: 20},
+		{Title: "IPv4", Width: 15},
+		{Title: "IPv6", Width: 35},
+		{Title: "Status", Width: 12},
+	}
+
+	// Use filtered clients if search is active, otherwise use all clients
+	displayClients := s.filtered
+	if !s.search.IsActive() {
+		displayClients = s.clients
+	}
+
+	var rows []table.Row
+	for _, cws := range displayClients {
+		row := table.Row{
+			cws.Client.Name,
+			cws.Client.IPv4,
+			cws.Client.IPv6,
+			cws.Status,
+		}
+		rows = append(rows, row)
+	}
+
+	// Sort rows based on current sort settings
+	s.sortRows(rows)
+
+	// Determine table height
+	tableHeight := len(rows) + 2 // Header + rows
+	if tableHeight < 5 {
+		tableHeight = 5
+	}
+
+	s.table = table.New(
+		table.WithColumns(columns),
+		table.WithRows(rows),
+		table.WithFocused(true),
+		table.WithHeight(tableHeight),
+	)
+
+	// Apply styles
+	s.setTableStyles()
+}
+
+// setTableStyles applies styling to the table
+func (s *ListScreen) setTableStyles() {
+	styles := table.DefaultStyles()
+	styles.Header = styles.Header.
+		BorderStyle(lipgloss.NormalBorder()).
+		BorderForeground(lipgloss.Color("240")).
+		BorderBottom(true).
+		Bold(true)
+	styles.Selected = styles.Selected.
+		Foreground(lipgloss.Color("229")).
+		Background(lipgloss.Color("57")).
+		Bold(false)
+	s.table.SetStyles(styles)
+}
+
+// sortRows sorts the rows based on the current sort settings
+func (s *ListScreen) sortRows(rows []table.Row) {
+	colIndex := s.getColumnIndex(s.sortedBy)
+
+	sort.Slice(rows, func(i, j int) bool {
+		var valI, valJ string
+		if colIndex < len(rows[i]) {
+			valI = rows[i][colIndex]
+		}
+		if colIndex < len(rows[j]) {
+			valJ = rows[j][colIndex]
+		}
+
+		if s.ascending {
+			return strings.ToLower(valI) < strings.ToLower(valJ)
+		}
+		return strings.ToLower(valI) > strings.ToLower(valJ)
+	})
+}
+
+// sortByColumn changes the sort column
+func (s *ListScreen) sortByColumn(col string) {
+	sortedBy := "Name"
+	switch col {
+	case "1":
+		sortedBy = "Name"
+	case "2":
+		sortedBy = "IPv4"
+	case "3":
+		sortedBy = "IPv6"
+	case "4":
+		sortedBy = "Status"
+	}
+
+	// Toggle direction if clicking same column
+	if s.sortedBy == sortedBy {
+		s.ascending = !s.ascending
+	} else {
+		s.sortedBy = sortedBy
+		s.ascending = true
+	}
+
+	s.buildTable()
+}
+
+// getColumnIndex returns the index of a column by name
+func (s *ListScreen) getColumnIndex(name string) int {
+	switch name {
+	case "Name":
+		return 0
+	case "IPv4":
+		return 1
+	case "IPv6":
+		return 2
+	case "Status":
+		return 3
+	}
+	return 0
+}
+
+// Messages
+
+// clientsLoadedMsg is sent when clients are loaded
+type clientsLoadedMsg struct {
+	clients []ClientWithStatus
+}
+
+// errMsg is sent when an error occurs
+type errMsg struct {
+	err error
+}