Implement proper error handling, add godoc comments, and implement expressions

defaults.go

@@ -0,0 +1,54 @@
+package scpt
+
+import (
+	"errors"
+	"fmt"
+	"github.com/gen2brain/dlgs"
+	"os"
+	"os/exec"
+)
+
+func displayDialog(args map[string]interface{}) (interface{}, error) {
+	title, ok := args["title"]
+	if !ok {
+		return nil, errors.New("title not provided")
+	}
+	text, ok := args[""]
+	if !ok {
+		return nil, errors.New("text not provided")
+	}
+	switch args["type"] {
+	case "yesno":
+		return dlgs.Question(fmt.Sprint(title), fmt.Sprint(text), true)
+	case "info":
+		return dlgs.Info(fmt.Sprint(title), fmt.Sprint(text))
+	case "error":
+		return dlgs.Error(fmt.Sprint(title), fmt.Sprint(text))
+	case "entry":
+		defaultText, ok := args["default"]
+		if !ok {
+			defaultText = ""
+		}
+		input, _, err := dlgs.Entry(fmt.Sprint(title), fmt.Sprint(text), fmt.Sprint(defaultText))
+		return input, err
+	default:
+		return nil, fmt.Errorf("unknown dialog type: %v", args["type"])
+	}
+}
+
+func doShellScript(args map[string]interface{}) (interface{}, error) {
+	script, ok := args[""].(string)
+	if ok {
+		cmd := exec.Command("sh", "-c", script)
+		cmd.Stdout = os.Stdout
+		_ = cmd.Run()
+		return "", nil
+	} else {
+		return nil, errors.New("script not provided")
+	}
+}
+
+func print(args map[string]interface{}) (interface{}, error) {
+	fmt.Println(args)
+	return nil, nil
+}