Markdown Preview in txti

When EDITING a txti (txti.es/*/edit) in txti.es you should be able to preview your changes (a toggle preview button appears)

คุณจะต้องติดตั้งส่วนขยาย เช่น Tampermonkey, Greasemonkey หรือ Violentmonkey เพื่อติดตั้งสคริปต์นี้

คุณจะต้องติดตั้งส่วนขยาย เช่น Tampermonkey หรือ Violentmonkey เพื่อติดตั้งสคริปต์นี้

คุณจะต้องติดตั้งส่วนขยาย เช่น Tampermonkey หรือ Violentmonkey เพื่อติดตั้งสคริปต์นี้

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name         Markdown Preview in txti
// @namespace    https://gist.github.com/AeonFr/f44a8b6f175d059f8328638a6a30ce4d
// @version      0.1
// @description  When EDITING a txti (txti.es/*/edit) in txti.es you should be able to preview your changes (a toggle preview button appears)
// @author       Francisco Cano
// @match        http://txti.es/*/edit
// @grant        none
// @run-at       document-end
// @require      https://cdnjs.cloudflare.com/ajax/libs/showdown/1.3.0/showdown.min.js
// ==/UserScript==

(function() {
    'use strict';
    function _(selector){
        return document.querySelector(selector);
    }
    window.addEventListener('load', function(){
        initMarkdownPreview();
    });
    var converter = false;
    function initMarkdownPreview(){
        if( _('#content-input') ){
            var elt = document.createElement('div'),
                converter =  new showdown.Converter();
            elt.id = 'content-preview';
            elt.style.display = 'none';
            _('#create-a-txti').insertBefore(elt, _('#content-input'));
            var contentToMarkdownPreviewer = function(){
                var result = converter.makeHtml(  _('#content-input').value );
                elt.innerHTML = result;
            };
            _('#content-input').addEventListener('keyup', contentToMarkdownPreviewer);
            // Fire the conversion the first time, when page is loaded
            contentToMarkdownPreviewer();
            var elt2 = document.createElement('div');
            elt2.innerHTML = '<a href="content-input" action="toggle-preview">Toggle Preview</a>';
            _('#create-a-txti').insertBefore(elt2, _('#content-preview'));
            elt2.addEventListener('click', function(e){
                e.preventDefault();
                if ( _('#content-input').style.display != 'none' ){
                    _('#content-input').style.display = 'none';
                    _('#content-preview').style.display = 'block';
                }else{
                    _('#content-input').style.display = 'block';
                    _('#content-preview').style.display = 'none';
                }
            });
        }
    }
})();