Add package manager example demonstrating tea.Printf

examples/package-manager/main.go

@@ -0,0 +1,139 @@
+package main
+
+import (
+	"fmt"
+	"math/rand"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/charmbracelet/bubbles/progress"
+	"github.com/charmbracelet/bubbles/spinner"
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/charmbracelet/lipgloss"
+)
+
+type model struct {
+	packages []string
+	index    int
+	width    int
+	height   int
+	spinner  spinner.Model
+	progress progress.Model
+	done     bool
+}
+
+var (
+	currentPkgNameStyle = lipgloss.NewStyle().Foreground(lipgloss.Color("211"))
+	subtleStyle         = lipgloss.NewStyle().Foreground(lipgloss.Color("239"))
+	doneStyle           = lipgloss.NewStyle().Margin(1, 2)
+	checkMark           = lipgloss.NewStyle().Foreground(lipgloss.Color("42")).SetString("✓")
+)
+
+func newModel() model {
+	p := progress.New(
+		progress.WithDefaultGradient(),
+		progress.WithWidth(40),
+		progress.WithoutPercentage(),
+	)
+	s := spinner.New()
+	s.Style = lipgloss.NewStyle().Foreground(lipgloss.Color("63"))
+	return model{
+		packages: getPackages(),
+		spinner:  s,
+		progress: p,
+	}
+}
+
+func (m model) Init() tea.Cmd {
+	return tea.Batch(downloadAndInstall(m.packages[m.index]), m.spinner.Tick)
+}
+
+func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
+	switch msg := msg.(type) {
+	case tea.WindowSizeMsg:
+		m.width, m.height = msg.Width, msg.Height
+	case tea.KeyMsg:
+		switch msg.String() {
+		case "ctrl+c", "esc", "q":
+			return m, tea.Quit
+		}
+	case installedPkgMsg:
+		if m.index >= len(m.packages)-1 {
+			// Everything's been installed. We're done!
+			m.done = true
+			return m, tea.Quit
+		}
+
+		// Update progress bar
+		progressCmd := m.progress.SetPercent(float64(m.index) / float64(len(m.packages)-1))
+
+		m.index++
+		return m, tea.Batch(
+			progressCmd,
+			tea.Printf("%s %s", checkMark, m.packages[m.index]), // print success message above our program
+			downloadAndInstall(m.packages[m.index]),             // download the next package
+		)
+	case spinner.TickMsg:
+		var cmd tea.Cmd
+		m.spinner, cmd = m.spinner.Update(msg)
+		return m, cmd
+	case progress.FrameMsg:
+		newModel, cmd := m.progress.Update(msg)
+		if newModel, ok := newModel.(progress.Model); ok {
+			m.progress = newModel
+		}
+		return m, cmd
+	}
+	return m, nil
+}
+
+func (m model) View() string {
+	n := len(m.packages)
+	w := lipgloss.Width(fmt.Sprintf("%d", n))
+
+	if m.done {
+		return doneStyle.Render(fmt.Sprintf("Done! Installed %d packages.\n", n))
+	}
+
+	pkgCount := fmt.Sprintf(" %*d/%*d", w, m.index, w, n-1)
+
+	spin := m.spinner.View() + " "
+	prog := m.progress.View()
+	cellsAvail := max(0, m.width-lipgloss.Width(spin+prog+pkgCount))
+
+	pkgName := currentPkgNameStyle.Render(m.packages[m.index])
+	info := lipgloss.NewStyle().MaxWidth(cellsAvail).Render("Installing " + pkgName)
+
+	cellsRemaining := max(0, m.width-lipgloss.Width(spin+info+prog+pkgCount))
+	gap := strings.Repeat(" ", cellsRemaining)
+
+	return spin + info + gap + prog + pkgCount
+}
+
+type installedPkgMsg string
+
+func downloadAndInstall(pkg string) tea.Cmd {
+	// This is where you'd do i/o stuff to download and install packages. In
+	// our case we're just pausing for a moment to simulate the process.
+	d := time.Millisecond * time.Duration(rand.Intn(500))
+	return tea.Tick(d, func(t time.Time) tea.Msg {
+		return installedPkgMsg(pkg)
+	})
+}
+
+func max(a, b int) int {
+	if a > b {
+		return a
+	}
+	return b
+}
+
+func main() {
+	rand.Seed(time.Now().UnixMicro())
+
+	if err := tea.NewProgram(newModel()).Start(); err != nil {
+		fmt.Println("Error running program:", err)
+		os.Exit(1)
+	}
+}

examples/package-manager/packages.go

@@ -0,0 +1,52 @@
+package main
+
+import (
+	"fmt"
+	"math/rand"
+)
+
+var packages = []string{
+	"vegeutils",
+	"libgardening",
+	"currykit",
+	"spicerack",
+	"fullenglish",
+	"eggy",
+	"bad-kitty",
+	"chai",
+	"hojicha",
+	"libtacos",
+	"babys-monads",
+	"libpurring",
+	"currywurst-devel",
+	"xmodmeow",
+	"licorice-utils",
+	"cashew-apple",
+	"rock-lobster",
+	"standmixer",
+	"coffee-CUPS",
+	"libesszet",
+	"zeichenorientierte-benutzerschnittstellen",
+	"schnurrkit",
+	"old-socks-devel",
+	"jalapeño",
+	"molasses-utils",
+	"xkohlrabi",
+	"party-gherkin",
+	"snow-peas",
+	"libyuzu",
+}
+
+func getPackages() []string {
+	pkgs := packages
+	copy(pkgs, packages)
+
+	rand.Shuffle(len(pkgs), func(i, j int) {
+		pkgs[i], pkgs[j] = pkgs[j], pkgs[i]
+	})
+
+	for k := range pkgs {
+		pkgs[k] += fmt.Sprintf("-%d.%d.%d", rand.Intn(10), rand.Intn(10), rand.Intn(10))
+	}
+	return pkgs
+}

standard_renderer.go

@@ -505,7 +505,7 @@ func Println(args ...interface{}) Cmd {
 // its own line.
 //
 // If the altscreen is active no output will be printed.
-func Printf(format string, args ...interface{}) Cmd {
+func Printf(template string, args ...interface{}) Cmd {
 	return func() Msg {
 		return printLineMessage{
 			messageBody: fmt.Sprintf(template, args...),