Add embedded web chat client (closes #7) (#8)

cmd/chat-cli/ui.go

@@ -0,0 +1,233 @@
+package main
+
+import (
+	"fmt"
+	"strings"
+	"time"
+
+	"github.com/gdamore/tcell/v2"
+	"github.com/rivo/tview"
+)
+
+// Buffer holds messages for a channel/DM/status window.
+type Buffer struct {
+	Name   string
+	Lines  []string
+	Unread int
+}
+
+// UI manages the terminal interface.
+type UI struct {
+	app       *tview.Application
+	messages  *tview.TextView
+	statusBar *tview.TextView
+	input     *tview.InputField
+	layout    *tview.Flex
+
+	buffers       []*Buffer
+	currentBuffer int
+
+	onInput func(string)
+}
+
+// NewUI creates the tview-based IRC-like UI.
+func NewUI() *UI {
+	ui := &UI{
+		app: tview.NewApplication(),
+		buffers: []*Buffer{
+			{Name: "(status)", Lines: nil},
+		},
+	}
+
+	// Message area.
+	ui.messages = tview.NewTextView().
+		SetDynamicColors(true).
+		SetScrollable(true).
+		SetWordWrap(true).
+		SetChangedFunc(func() {
+			ui.app.Draw()
+		})
+	ui.messages.SetBorder(false)
+
+	// Status bar.
+	ui.statusBar = tview.NewTextView().
+		SetDynamicColors(true)
+	ui.statusBar.SetBackgroundColor(tcell.ColorNavy)
+	ui.statusBar.SetTextColor(tcell.ColorWhite)
+
+	// Input field.
+	ui.input = tview.NewInputField().
+		SetFieldBackgroundColor(tcell.ColorBlack).
+		SetFieldTextColor(tcell.ColorWhite)
+	ui.input.SetDoneFunc(func(key tcell.Key) {
+		if key == tcell.KeyEnter {
+			text := ui.input.GetText()
+			if text == "" {
+				return
+			}
+			ui.input.SetText("")
+			if ui.onInput != nil {
+				ui.onInput(text)
+			}
+		}
+	})
+
+	// Capture Alt+N for window switching.
+	ui.app.SetInputCapture(func(event *tcell.EventKey) *tcell.EventKey {
+		if event.Modifiers()&tcell.ModAlt != 0 {
+			r := event.Rune()
+			if r >= '0' && r <= '9' {
+				idx := int(r - '0')
+				ui.SwitchBuffer(idx)
+				return nil
+			}
+		}
+		return event
+	})
+
+	// Layout: messages on top, status bar, input at bottom.
+	ui.layout = tview.NewFlex().SetDirection(tview.FlexRow).
+		AddItem(ui.messages, 0, 1, false).
+		AddItem(ui.statusBar, 1, 0, false).
+		AddItem(ui.input, 1, 0, true)
+
+	ui.app.SetRoot(ui.layout, true)
+	ui.app.SetFocus(ui.input)
+
+	return ui
+}
+
+// Run starts the UI event loop (blocks).
+func (ui *UI) Run() error {
+	return ui.app.Run()
+}
+
+// Stop stops the UI.
+func (ui *UI) Stop() {
+	ui.app.Stop()
+}
+
+// OnInput sets the callback for user input.
+func (ui *UI) OnInput(fn func(string)) {
+	ui.onInput = fn
+}
+
+// AddLine adds a line to the specified buffer.
+func (ui *UI) AddLine(bufferName string, line string) {
+	ui.app.QueueUpdateDraw(func() {
+		buf := ui.getOrCreateBuffer(bufferName)
+		buf.Lines = append(buf.Lines, line)
+
+		// Mark unread if not currently viewing this buffer.
+		if ui.buffers[ui.currentBuffer] != buf {
+			buf.Unread++
+			ui.refreshStatus()
+		}
+
+		// If viewing this buffer, append to display.
+		if ui.buffers[ui.currentBuffer] == buf {
+			fmt.Fprintln(ui.messages, line)
+		}
+	})
+}
+
+// AddStatus adds a line to the status buffer (buffer 0).
+func (ui *UI) AddStatus(line string) {
+	ts := time.Now().Format("15:04")
+	ui.AddLine("(status)", fmt.Sprintf("[gray]%s[white] %s", ts, line))
+}
+
+// SwitchBuffer switches to the buffer at index n.
+func (ui *UI) SwitchBuffer(n int) {
+	ui.app.QueueUpdateDraw(func() {
+		if n < 0 || n >= len(ui.buffers) {
+			return
+		}
+		ui.currentBuffer = n
+		buf := ui.buffers[n]
+		buf.Unread = 0
+		ui.messages.Clear()
+		for _, line := range buf.Lines {
+			fmt.Fprintln(ui.messages, line)
+		}
+		ui.messages.ScrollToEnd()
+		ui.refreshStatus()
+	})
+}
+
+// SwitchToBuffer switches to the named buffer, creating it if needed.
+func (ui *UI) SwitchToBuffer(name string) {
+	ui.app.QueueUpdateDraw(func() {
+		buf := ui.getOrCreateBuffer(name)
+		for i, b := range ui.buffers {
+			if b == buf {
+				ui.currentBuffer = i
+				break
+			}
+		}
+		buf.Unread = 0
+		ui.messages.Clear()
+		for _, line := range buf.Lines {
+			fmt.Fprintln(ui.messages, line)
+		}
+		ui.messages.ScrollToEnd()
+		ui.refreshStatus()
+	})
+}
+
+// SetStatus updates the status bar text.
+func (ui *UI) SetStatus(nick, target, connStatus string) {
+	ui.app.QueueUpdateDraw(func() {
+		ui.refreshStatusWith(nick, target, connStatus)
+	})
+}
+
+func (ui *UI) refreshStatus() {
+	// Will be called from the main goroutine via QueueUpdateDraw parent.
+	// Rebuild status from app state — caller must provide context.
+}
+
+func (ui *UI) refreshStatusWith(nick, target, connStatus string) {
+	var unreadParts []string
+	for i, buf := range ui.buffers {
+		if buf.Unread > 0 {
+			unreadParts = append(unreadParts, fmt.Sprintf("%d:%s(%d)", i, buf.Name, buf.Unread))
+		}
+	}
+	unread := ""
+	if len(unreadParts) > 0 {
+		unread = " [Act: " + strings.Join(unreadParts, ",") + "]"
+	}
+
+	bufInfo := fmt.Sprintf("[%d:%s]", ui.currentBuffer, ui.buffers[ui.currentBuffer].Name)
+
+	ui.statusBar.Clear()
+	fmt.Fprintf(ui.statusBar, " [%s] %s %s %s%s",
+		connStatus, nick, bufInfo, target, unread)
+}
+
+func (ui *UI) getOrCreateBuffer(name string) *Buffer {
+	for _, buf := range ui.buffers {
+		if buf.Name == name {
+			return buf
+		}
+	}
+	buf := &Buffer{Name: name}
+	ui.buffers = append(ui.buffers, buf)
+	return buf
+}
+
+// BufferCount returns the number of buffers.
+func (ui *UI) BufferCount() int {
+	return len(ui.buffers)
+}
+
+// BufferIndex returns the index of a named buffer, or -1.
+func (ui *UI) BufferIndex(name string) int {
+	for i, buf := range ui.buffers {
+		if buf.Name == name {
+			return i
+		}
+	}
+	return -1
+}