1 files changed, 126 insertions, 0 deletions
diff --git a/tui/post.go b/tui/post.go
new file mode 100644
index 0000000..7762b56
--- /dev/null
+++ b/tui/post.go
@@ -0,0 +1,126 @@
+package tui
+
+// An example program demonstrating the pager component from the Bubbles
+// component library.
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/charmbracelet/bubbles/viewport"
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/charmbracelet/lipgloss"
+)
+
+// You generally won't need this unless you're processing stuff with
+// complicated ANSI escape sequences. Turn it on if you notice flickering.
+//
+// Also keep in mind that high performance rendering only works for programs
+// that use the full size of the terminal. We're enabling that below with
+// tea.EnterAltScreen().
+const useHighPerformanceRenderer = false
+
+var (
+	titleStyle = func() lipgloss.Style {
+		b := lipgloss.RoundedBorder()
+		b.Right = "├"
+		return lipgloss.NewStyle().BorderStyle(b).Padding(0, 1)
+	}()
+
+	infoStyle = func() lipgloss.Style {
+		b := lipgloss.RoundedBorder()
+		b.Left = "┤"
+		return titleStyle.BorderStyle(b)
+	}()
+)
+
+type PostModel struct {
+	content  string
+	ready    bool
+	viewport viewport.Model
+}
+
+func (m PostModel) Init() tea.Cmd {
+	return nil
+}
+
+func (m PostModel) Update(msg tea.Msg) (PostModel, tea.Cmd) {
+	var (
+		cmd  tea.Cmd
+		cmds []tea.Cmd
+	)
+
+	switch msg := msg.(type) {
+	case tea.KeyMsg:
+		if k := msg.String(); k == "ctrl+c" || k == "q" || k == "esc" {
+			return m, tea.Quit
+		}
+
+	case tea.WindowSizeMsg:
+		headerHeight := lipgloss.Height(m.headerView())
+		footerHeight := lipgloss.Height(m.footerView())
+		verticalMarginHeight := headerHeight + footerHeight
+
+		if !m.ready {
+			// Since this program is using the full size of the viewport we
+			// need to wait until we've received the window dimensions before
+			// we can initialize the viewport. The initial dimensions come in
+			// quickly, though asynchronously, which is why we wait for them
+			// here.
+			m.viewport = viewport.New(msg.Width, msg.Height-verticalMarginHeight)
+			m.viewport.YPosition = headerHeight
+			m.viewport.HighPerformanceRendering = useHighPerformanceRenderer
+			m.viewport.SetContent(m.content)
+			m.ready = true
+
+			// This is only necessary for high performance rendering, which in
+			// most cases you won't need.
+			//
+			// Render the viewport one line below the header.
+			m.viewport.YPosition = headerHeight + 1
+		} else {
+			m.viewport.Width = msg.Width
+			m.viewport.Height = msg.Height - verticalMarginHeight
+		}
+
+		if useHighPerformanceRenderer {
+			// Render (or re-render) the whole viewport. Necessary both to
+			// initialize the viewport and when the window is resized.
+			//
+			// This is needed for high-performance rendering only.
+			cmds = append(cmds, viewport.Sync(m.viewport))
+		}
+	}
+
+	// Handle keyboard and mouse events in the viewport
+	m.viewport, cmd = m.viewport.Update(msg)
+	cmds = append(cmds, cmd)
+
+	return m, tea.Batch(cmds...)
+}
+
+func (m PostModel) View() string {
+	if !m.ready {
+		return "\n  Initializing..."
+	}
+	return fmt.Sprintf("%s\n%s\n%s", m.headerView(), m.viewport.View(), m.footerView())
+}
+
+func (m PostModel) headerView() string {
+	title := titleStyle.Render("Mr. Pager")
+	line := strings.Repeat("─", max(0, m.viewport.Width-lipgloss.Width(title)))
+	return lipgloss.JoinHorizontal(lipgloss.Center, title, line)
+}
+
+func (m PostModel) footerView() string {
+	info := infoStyle.Render(fmt.Sprintf("%3.f%%", m.viewport.ScrollPercent()*100))
+	line := strings.Repeat("─", max(0, m.viewport.Width-lipgloss.Width(info)))
+	return lipgloss.JoinHorizontal(lipgloss.Center, line, info)
+}
+
+func max(a, b int) int {
+	if a > b {
+		return a
+	}
+	return b
+}