sample7.go

package main

import (
	"bytes"
	"encoding/json"
	"syscall/js"
)

func editionMode(this js.Value, args []js.Value) interface{} {
	if len(args) != 1 {
		js.Global().Call("alert", "Invalid no of arguments passed")
		return nil
	}
	inputTextArea := args[0]
	if inputTextArea.Get("classList").Call("contains", "success").Bool() {
		inputTextArea.Get("classList").Call("remove", "success")
	}
	if inputTextArea.Get("classList").Call("contains", "error").Bool() {
		inputTextArea.Get("classList").Call("remove", "error")
	}
	document := js.Global().Get("document")
	outputTextArea := document.Call("getElementById", "output")
	outputTextArea.Set("value", "")
	inputTextArea.Get("classList").Call("add", "info")
	return nil
}

func prettify(this js.Value, args []js.Value) interface{} {
	if len(args) != 1 {
		js.Global().Call("alert", "Invalid no of arguments passed")
		return nil
	}
	document := js.Global().Get("document")
	inputTextArea := args[0]
	inputTextArea.Get("classList").Call("remove", "info")
	text := inputTextArea.Get("value").String()
	outputTextArea := document.Call("getElementById", "output")
	var output bytes.Buffer
	err := json.Indent(&output, []byte(text), "", "  ")
	if err != nil {
		if inputTextArea.Get("classList").Call("contains", "success").Bool() {
			inputTextArea.Get("classList").Call("remove", "success")
		}
		inputTextArea.Get("classList").Call("add", "error")
		println(err.Error())
		return nil
	}
	outputTextArea.Set("value", output.String())
	if inputTextArea.Get("classList").Call("contains", "error").Bool() {
		inputTextArea.Get("classList").Call("remove", "error")
	}
	inputTextArea.Get("classList").Call("add", "success")
	return nil
}

func main() {
	js.Global().Set("prettify", js.FuncOf(prettify))
	js.Global().Set("editionMode", js.FuncOf(editionMode))
	c := make(chan int)
	<-c
}