feat: Add gum write command

Write provides a shell script interface for the text area bubble. It can
be used to ask the user to write some long form of text (multi-line)
input. The text the user entered will be sent to stdout.

```
gum write > output.text
```

main.go

@@ -21,6 +21,8 @@ func main() {
 	switch ctx.Command() {
 	case "input":
 		pop.Input.Run()
+	case "write":
+		pop.Write.Run()
 	case "search":
 		pop.Search.Run()
 	case "spin <command>":

pop.go

@@ -5,6 +5,7 @@ import (
 	"github.com/charmbracelet/sodapop/search"
 	"github.com/charmbracelet/sodapop/spin"
 	"github.com/charmbracelet/sodapop/style"
+	"github.com/charmbracelet/sodapop/write"
 )
 
 // Pop is the command-line interface for Soda Pop.
@@ -19,6 +20,16 @@ type Pop struct {
 	//
 	Input input.Options `cmd:"" help:"Prompt for input."`
 
+	// Write provides a shell script interface for the text area bubble.
+	// https://github.com/charmbracelet/bubbles/textarea
+	//
+	// It can be used to ask the user to write some long form of text
+	// (multi-line) input. The text the user entered will be sent to stdout.
+	//
+	//   $ pop write > output.text
+	//
+	Write write.Options `cmd:"" help:"Prompt for text"`
+
 	// Search provides a fuzzy searching text input to allow filtering a list of
 	// options to select one option.
 	//

write/command.go

@@ -0,0 +1,31 @@
+package write
+
+import (
+	"fmt"
+	"os"
+
+	"github.com/charmbracelet/bubbles/textarea"
+	tea "github.com/charmbracelet/bubbletea"
+	"github.com/charmbracelet/lipgloss"
+)
+
+// Run provides a shell script interface for the text area bubble.
+// https://github.com/charmbracelet/bubbles/textarea
+func (o Options) Run() {
+	a := textarea.New()
+	a.Focus()
+
+	a.Prompt = o.Prompt
+	a.Placeholder = o.Placeholder
+	a.ShowLineNumbers = o.ShowLineNumbers
+	if !o.ShowCursorLine {
+		a.FocusedStyle.CursorLine = lipgloss.NewStyle()
+		a.BlurredStyle.CursorLine = lipgloss.NewStyle()
+	}
+
+	a.SetWidth(o.Width)
+
+	p := tea.NewProgram(model{a}, tea.WithOutput(os.Stderr))
+	m, _ := p.StartReturningModel()
+	fmt.Println(m.(model).textarea.Value())
+}

write/options.go

@@ -0,0 +1,11 @@
+package write
+
+// Options are the customization options for the textarea.
+type Options struct {
+	ShowCursorLine  bool   `help:"Show cursor line" default:"true"`
+	ShowLineNumbers bool   `help:"Show line numbers" default:"true"`
+	Placeholder     string `help:"Placeholder value" default:"Write something..."`
+	Prompt          string `help:"Prompt to display" default:"┃ "`
+	Width           int    `help:"Text area width" default:"50"`
+	Height          int    `help:"Text area height" default:"5"`
+}

write/write.go

@@ -0,0 +1,24 @@
+package write
+
+import (
+	"github.com/charmbracelet/bubbles/textarea"
+	tea "github.com/charmbracelet/bubbletea"
+)
+
+type model struct{ textarea textarea.Model }
+
+func (m model) Init() tea.Cmd { return textarea.Blink }
+func (m model) View() string  { return m.textarea.View() }
+func (m model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
+	switch msg := msg.(type) {
+	case tea.KeyMsg:
+		switch msg.Type {
+		case tea.KeyEscape, tea.KeyCtrlC:
+			return m, tea.Quit
+		}
+	}
+
+	var cmd tea.Cmd
+	m.textarea, cmd = m.textarea.Update(msg)
+	return m, cmd
+}