Initial commit for http rest bridge

http_rest_frontend/cli/accounts_util.go

@@ -0,0 +1,24 @@
+package cli
+
+import (
+	"strconv"
+
+	"github.com/ProtonMail/proton-bridge/internal/frontend/types"
+)
+
+func (f *frontendCLI) getUserByIndexOrName(account string) types.User {
+	users := f.bridge.GetUsers()
+	numberOfAccounts := len(users)
+	if index, err := strconv.Atoi(account); err == nil {
+		if index < 0 || index >= numberOfAccounts {
+			return nil
+		}
+		return users[index]
+	}
+	for _, user := range users {
+		if user.Username() == account {
+			return user
+		}
+	}
+	return nil
+}