Initial, working but only with viewport height adjusted a little bit

ui/view.go

@@ -0,0 +1,56 @@
+package ui
+
+import (
+	"bytes"
+	"fmt"
+	"slices"
+	"strings"
+
+	"github.com/alecthomas/chroma/v2/formatters"
+	"github.com/alecthomas/chroma/v2/lexers"
+	"github.com/alecthomas/chroma/v2/styles"
+	"github.com/charmbracelet/lipgloss"
+)
+
+var panelStyle = lipgloss.NewStyle().Border(lipgloss.NormalBorder())
+
+func (m Model) View() string {
+	var buf bytes.Buffer
+	lexer := lexers.Get("python")
+	style := styles.Get("monokai")
+	formatter := formatters.Get("terminal16m")
+
+	iterator, _ := lexer.Tokenise(nil, m.text)
+	formatter.Format(&buf, style, iterator)
+
+	var out strings.Builder
+
+	lines := strings.Split(buf.String(), "\n")
+	breakpoints := m.breakpoints[m.currentFile]
+
+	for i, line := range lines {
+		breakpoint := " "
+		cursor := " "
+
+		if slices.Contains(breakpoints, i+1) {
+			breakpoint = "O"
+		}
+
+		if i == m.cursor {
+			cursor = ">"
+		}
+		fmt.Fprintf(&out, "%-4d%s%s %s\n", i+1, breakpoint, cursor, line)
+	}
+
+	frameW, frameH := panelStyle.GetFrameSize()
+	topHeight := m.height * 70 / 100
+
+	code := panelStyle.Width(m.width - frameW).Height(topHeight - frameH).Render(out.String())
+	m.viewport.Height = m.height - (topHeight + frameH)
+	m.viewport.Width = m.width - frameW
+	m.viewport.SetContent(strings.Join(m.messages, ""))
+	m.viewport.GotoBottom()
+	output := panelStyle.Width(m.viewport.Width).Height(m.viewport.Height).Render(m.viewport.View())
+
+	return lipgloss.JoinVertical(lipgloss.Top, code, output)
+}