darkred / Markdown toolbar for reddit.com

// ==UserScript==
// @name        Markdown toolbar for reddit.com
// @namespace   darkred
// @author      wOxxOm, darkred
// @license     MIT
// @description Creates a Markdown toolbar whenever you make/edit text posts or comments in reddit.com.
// @version     1.3
// @include     https://www.reddit.com/*submit*
// @include     https://www.reddit.com/*comments*
// @grant       GM_addStyle
// @icon        https://raw.githubusercontent.com/dcurtis/markdown-mark/master/png/66x40-solid.png
//
//
// This is a modified version of the script "Markdown toolbar for GreasyFork and UserStyles.org" ()https://greasyfork.org/en/scripts/6779-markdown-toolbar-for-greasyfork-and-userstyles-org)
// Thanks a lot to wOxxOm for making that script.
//
// ==/UserScript==


var x;

// IF IT'S A SUBMIT PAGE
if (window.location.href.indexOf('submit') > - 1) {
	// THEN ADD TOOLBAR TO THE 'NEW POST' TEXTBOX
	x = document.querySelectorAll('div.md > textarea:nth-child(1)')[0].parentNode;
	addFeatures(x);
}
else {
	var textareas = document.querySelectorAll('textarea');

	// ADD TOOLBAR: TO EDITING YOUR POST, TO 'NEW COMMENT' FORM AND TO EDITING YOUR EXISTING COMMENT(S)
	for (i = 0; i < textareas.length - 2; i++) {
		x = document.querySelectorAll('textarea') [i].parentNode;
		addFeatures(x);
	}
}





function addFeatures(n) {

	n.parentNode.textAreaNode = x.firstChild;

	GM_addStyle('\
			.Button {\
					display: inline-block;\
					cursor: pointer;\
					margin: 0px;\
					font-size: 12px;\
					line-height: 1;\
					font-weight: bold;\
					padding: 4px 6px;\
					background: -moz-linear-gradient(center bottom , #CCC 0%, #FAFAFA 100%) repeat scroll 0% 0% #F8F8F8;\
					border: 1px solid #999;\
					border-radius: 2px;\
					white-space: nowrap;\
					text-shadow: 0px 1px 0px #FFF;\
					box-shadow: 0px 1px 0px #FFF inset, 0px -1px 2px #BBB inset;\
					color: #333;}');


	// add buttons
	btnMake(n, '<b>B</b>', 'Bold', '**');
	btnMake(n, '<i>I</i>', 'Italic', '*');
	// btnMake(n, '<u>U</u>', 'Underline', '<u>','</u>');
	// btnMake(n, '<s>S</s>', 'Strikethrough', '<s>','</s>');
	btnMake(n, '<s>S</s>', 'Strikethrough', '~~');
	btnMake(n, '^', 'Superscript', '^','', true);
	btnMake(n, '\\n', 'Line break', '&nbsp;\n', '', true);
	btnMake(n, '---', 'Horizontal line', '\n\n---\n\n', '', true);
	btnMake(n, 'URL', 'Add URL to selected text',
		function(e) {
			try {edWrapInTag('[', ']('+prompt('URL'+':')+')', edInit(e.target));}
			catch(e) {}
		});
	// btnMake(n, 'Image', 'Convert selected https://url to inline image', '!['+'image'+'](', ')');
	btnMake(n, 'Table', 'Insert table template', '\n| head1 | head2 |\n|-------|-------|\n| cell1 | cell2 |\n| cell3 | cell4 |\n', '', true);
	btnMake(n, 'Code', 'Apply CODE markdown to selected text',
		function(e){
			var ed = edInit(e.target);
			if (ed.sel.indexOf('\n') < 0)
				edWrapInTag('`', '`', ed);
			else
				edWrapInTag(((ed.sel1==0) || (ed.text.charAt(ed.sel1-1) == '\n') ? '' : '\n') + '```' + (ed.sel.charAt(0) == '\n' ? '' : '\n'),
					(ed.sel.substr(-1) == '\n' ? '' : '\n') + '```' + (ed.text.substr(ed.sel2,1) == '\n' ? '' : '\n'),
					ed);
		});
}

function btnMake(afterNode, label, title, tag1, tag2, noWrap) {
	var a = document.createElement('a');
	a.className = 'Button';
	a.innerHTML = label;
	a.title = title;
	a.style.setProperty('float','right');

	a.addEventListener('click',
		typeof(tag1) === 'function'
			? tag1
			: noWrap ? function(e){edInsertText(tag1, edInit(e.target));}
				: function(e){edWrapInTag(tag1, tag2, edInit(e.target));});

	var nparent = afterNode.parentNode;
	a.textAreaNode = nparent.textAreaNode;
	nparent.insertBefore(a, nparent.firstElementChild);
}



function edInit(btn) {

	var ed = {node: btn.parentNode.textAreaNode } ;

	ed.sel1 = ed.node.selectionStart;
	ed.sel2 = ed.node.selectionEnd,
	ed.text = ed.node.value;
	ed.sel = ed.text.substring(ed.sel1, ed.sel2);
	return ed;
}




function edWrapInTag(tag1, tag2, ed) {
	ed.node.value = ed.text.substr(0, ed.sel1) + tag1 + ed.sel + (tag2?tag2:tag1) + ed.text.substr(ed.sel2);
	ed.node.setSelectionRange(ed.sel1 + tag1.length, ed.sel1 + tag1.length + ed.sel.length);
	ed.node.focus();
}

function edInsertText(text, ed) {
	ed.node.value = ed.text.substr(0, ed.sel2) + text + ed.text.substr(ed.sel2);
	ed.node.setSelectionRange(ed.sel2 + text.length, ed.sel2 + text.length);
	ed.node.focus();
}