feat: send email

main.go

@@ -1,12 +1,15 @@
 package main
 
 import (
+	"fmt"
 	"os"
 
 	tea "github.com/charmbracelet/bubbletea"
 	"github.com/spf13/cobra"
 )
 
+const RESEND_API_KEY = "RESEND_API_KEY"
+
 var rootCmd = &cobra.Command{
 	Use:   "email",
 	Short: "email is a command line interface for sending emails.",
@@ -22,6 +25,13 @@ var rootCmd = &cobra.Command{
 }
 
 func main() {
+	key := os.Getenv(RESEND_API_KEY)
+	if key == "" {
+		fmt.Printf("\n  %s %s %s\n\n", errorHeaderStyle.String(), inlineCodeStyle.Render(RESEND_API_KEY), "environment variable is required.")
+		fmt.Printf("  %s %s\n\n", commentStyle.Render("You can grab one at"), linkStyle.Render("https://resend.com"))
+		os.Exit(1)
+	}
+
 	err := rootCmd.Execute()
 	if err != nil {
 		os.Exit(1)