markdown.js

// Total.js Markdown
// The MIT License
// Copyright 2018-2024 (c) Peter Širka <petersirka@gmail.com>

const REG_DASH = /-{2,}/g;
const REG_TAGS = /<[^>]*>/g;
const REG_EMPTYCHAR = /\s|\W/;
const REG_ICONS = /(^|[^\w]):((fab|far|fas|fal|fad|fa|ti)\s(fa|ti)-)?[a-z-]+:([^\w]|$)/g;
const REG_KEYWORDS = /\{.*?\}\(.*?\)/g;
const REG_LINKEXTERNAL = /(https|http):\/\//;
const REG_FORMAT = /__.*?__|_.*?_|\*\*.*?\*\*|\*.*?\*|~~.*?~~|~.*?~/g;
const REG_ORDERED = /^[a-z|0-9]{1,3}\.\s|^(-|\*|\+)\s/i;
const REG_ORDEREDSIZE = /^(\s|\t)+/;
const REG_CODE = /`.*?`/g;
const REG_ENCODETAGS = /<|>/g;
const ENCODE = val => '&' + (val === '<' ? 'lt' : 'gt') + ';';
const REG_NIL = /\0/g;

function markdown_code(value) {
	return value ? ('<code>' + value.substring(1, value.length - 1) + '</code>') : '';
}

function markdown_imagelinks(value) {

	if (!value)
		return '';

	var end = value.lastIndexOf(')') + 1;
	var img = value.substring(0, end);
	var url = value.substring(end + 2, value.length - 1);
	var label = markdown_links(img);
	var footnote = label.substring(0, 13);

	if (footnote === '<sup data-id=' || footnote === '<span data-id' || label.substring(0, 9) === '<a href="')
		return label;

	return '<a href="' + url + '"' + (REG_LINKEXTERNAL.test(url) ? ' target="_blank"' : '') + '>' + label + '</a>';
}

function markdown_table(value, align, ishead) {

	var columns = value.substring(1, value.length - 1).split('|');
	var builder = '';

	for (var i = 0; i < columns.length; i++) {
		var column = columns[i].trim();
		if (column.charAt(0) != '-') {
			var a = align[i];
			builder += '<' + (ishead ? 'th' : 'td') + (a && a !== 'left' ? (' class="' + a + '"') : '') + '>' + column + '</' + (ishead ? 'th' : 'td') + '>';
		}
	}

	return '<tr>' + builder + '</tr>';
}

function markdown_links(value) {

	if (!value)
		return '';

	var end = value.lastIndexOf(']');
	var img = value.charAt(0) === '!';
	var text = value.substring(img ? 2 : 1, end);
	var link = value.substring(end + 2, value.length - 1);

	// footnotes
	if ((/^#\d+$/).test(link))
		return (/^\d+$/).test(text) ? '<sup data-id="{0}" class="markdown-footnote">{1}</sup>'.format(link.substring(1), text) : '<span data-id="{0}" class="markdown-footnote">{1}</span>'.format(link.substring(1), text);

	if (link.isEmail())
		return '<a href="mailto:' + link + '" rel="nofollow">' + text + '</a>';

	if (link.isPhone())
		return '<a href="tel:' + link + '" rel="nofollow">' + text + '</a>';

	if (link.substring(0, 4) === 'www.')
		link = 'https://' + link;

	var nofollow = link.charAt(0) === '@' ? ' rel="nofollow"' : REG_LINKEXTERNAL.test(link) ? ' target="_blank"' : '';
	return '<a href="' + link + '"' + nofollow + '>' + text + '</a>';
}

function markdown_image(value) {

	var end = value.lastIndexOf(']');
	var text = value.substring(2, end);
	var link = value.substring(end + 2, value.length - 1);
	var responsive = 1;
	var f = text.charAt(0);

	if (f === '+') {
		responsive = 2;
		text = text.substring(1);
	} else if (f === '-') {
		// gallery
		responsive = 3;
		text = text.substring(1);
	}

	return '<img src="' + link + '" alt="' + text + '"' + (responsive === 1 ? ' class="img-responsive"' : responsive === 3 ? ' class="markdown-gallery"' : '') + ' border="0" loading="lazy" />';
}

function markdown_keywords(value) {
	var keyword = value.substring(1, value.indexOf('}'));
	var type = value.substring(value.lastIndexOf('(') + 1, value.lastIndexOf(')'));
	return '<span class="markdown-keyword" data-type="{0}">{1}</span>'.format(type, keyword);
}

function markdown_links2(value) {
	value = value.substring(4, value.length - 4);
	return '<a href="' + (value.isEmail() ? 'mailto:' : REG_LINKEXTERNAL.test(value) ? '' : 'http://') + value + '" target="_blank">' + value + '</a>';
}

function markdown_format(value, index, text) {

	var p = text.charAt(index - 1);
	var n = text.charAt(index + value.length);

	if ((!p || REG_EMPTYCHAR.test(p)) && (!n || REG_EMPTYCHAR.test(n))) {

		var beg = '';
		var end = '';
		var tag;

		if (value.indexOf('*') !== -1) {
			tag = value.indexOf('**') === -1 ? 'em' : 'strong';
			beg += '<' + tag + '>';
			end = '</' + tag + '>' + end;
		}

		if (value.indexOf('_') !== -1) {
			tag = value.indexOf('__') === -1 ? 'u' : 'b';
			beg += '<' + tag + '>';
			end = '</' + tag + '>' + end;
		}

		if (value.indexOf('~') !== -1) {
			beg += '<strike>';
			end = '</strike>' + end;
		}

		var count = value.charAt(1) === value.charAt(0) ? 2 : 1;
		return beg + value.substring(count, value.length - count) + end;
	}

	return value;
}

function markdown_id(prefix, value) {
	value = value.replace(REG_TAGS, '');
	return prefix + value.slug().replace(REG_DASH, '-');
}

function markdown_icon(value) {

	var beg = -1;
	var end = -1;

	for (var i = 0; i < value.length; i++) {
		var code = value.charCodeAt(i);
		if (code === 58) {
			if (beg === -1)
				beg = i + 1;
			else
				end = i;
		}
	}

	var icon = value.substring(beg, end);
	if (icon.indexOf(' ') === -1)
		icon = 'ti ti-' + icon;
	return value.substring(0, beg - 1) + '<i class="' + icon + '"></i>' + value.substring(end + 1);
}

function markdown_urlify(str) {
	return str.replace(/(^|\s)+(((https?:\/\/)|(www\.))[^\s]+)/g, function(url, b, c) {
		var len = url.length;
		var l = url.charAt(len - 1);
		var f = url.charAt(0);
		if (l === '.' || l === ',')
			url = url.substring(0, len - 1);
		else
			l = '';
		url = (c === 'www.' ? 'http://' + url : url).trim();
		return (f.charCodeAt(0) < 40 ? f : '') + '[' + url + '](' + url + ')' + l;
	});
}

function parseul(builder) {

	var ul = {};
	var is = false;
	var currentindex = -1;
	var output = [];

	for (var i = 0; i < builder.length; i++) {

		var line = builder[i];

		if (line.charAt(0) === '\0') {

			if (!is)
				currentindex = output.push('<ul />') - 1;

			var key = currentindex + '';
			is = true;

			var tmp = line.substring(1);
			var index = tmp.indexOf('<');
			var obj = {};
			obj.index = i;
			obj.type = tmp.substring(0, 2);
			obj.offset = +tmp.substring(2, index).trim();
			obj.line = line.substring(index + 1);

			if (ul[key])
				ul[key].push(obj);
			else
				ul[key] = [obj];

		} else {
			output.push(line);
			is = false;
		}
	}

	for (var key in ul) {

		var line = +key;
		var arr = ul[key];
		var lines = [];
		var tags = [];
		var prev = null;
		var diff = null;
		var init = false;
		var tmp = null;

		for (var i = 0; i < arr.length; i++) {

			var li = arr[i];
			var beg = li.type === 'ul' ? '<ul>' : li.type === 'o1' ? '<ol type="1">' : '<ol type="a">';
			var end = li.type === 'ul' ? '</ul>' : '</ol>';

			var diff = li.offset - (prev ? prev.offset : 0);

			// Init
			if (!init) {
				init = true;
				lines.push(beg);
				tags.push(end);
			}

			if (diff > 0) {
				var last = lines[lines.length - 1];
				last = last.replace(/<\/li>$/, '');
				lines[lines.length - 1] = last;
				tags.push(end + '</li>');
				lines.push(beg);
				lines.push(li.line);
			} else if (diff < 0) {
				while (diff < 0) {
					tmp = tags.pop();
					lines.push(tmp);
					diff++;
				}
				lines.push(li.line);
			} else {
				lines.push(li.line);
			}

			prev = li;

		}

		while (tags.length)
			lines.push(tags.pop());

		output[line] = lines.join('\n');
	}

	return output;
}

function formatline(line) {
	var tmp = [];
	return line.replace(REG_CODE, function(text) {
		tmp.push(text);
		return '\0';
	}).replace(REG_FORMAT, markdown_format).replace(REG_NIL, () => markdown_code(tmp.shift()));
}

function imagescope(val) {

	var beg = -1;
	var can = false;
	var n;

	for (var i = 0; i < val.length; i++) {
		var c = val.charAt(i);

		if (c === '[') {
			beg = i;
			can = false;
			continue;
		}

		if (c === ']') {

			can = false;

			if (beg === -1)
				continue;

			n = val.charAt(i + 1);

			// maybe a link mistake
			if (n === ' ')
				n = val.charAt(i + 2);

			// maybe a link
			can = n === '(';
		}

		if (beg > -1 && can && c === ')') {
			n = val.charAt(beg - 1);
			var tmp = val.substring(beg - (n === '!' ? 1 : 0), i + 1);
			if (tmp.charAt(0) === '!')
				val = val.replace(tmp, markdown_image(tmp));
			can = false;
			beg = -1;
		}
	}

	return val;
}

function linkscope(val, index, callback) {

	var beg = -1;
	var beg2 = -1;
	var can = false;
	var skip = false;
	var find = false;
	var n;

	for (var i = index; i < val.length; i++) {
		var c = val.charAt(i);

		if (c === '[') {
			beg = i;
			can = false;
			find = true;
			continue;
		}

		var codescope = val.substring(i, i + 6);

		if (skip && codescope === '</code') {
			skip = false;
			i += 7;
			continue;
		}

		if (skip)
			continue;

		if (!find && codescope === '<code>') {
			skip = true;
			continue;
		}

		var il = val.substring(i, i + 4);

		if (il === '&lt;') {
			beg2 = i;
			continue;
		} else if (beg2 > -1 && il === '&gt;') {
			callback(val.substring(beg2, i + 4), true);
			beg2 = -1;
			continue;
		}

		if (c === ']') {

			can = false;
			find = false;

			if (beg === -1)
				continue;

			n = val.charAt(i + 1);

			// maybe a link mistake
			if (n === ' ')
				n = val.charAt(i + 2);

			// maybe a link
			can = n === '(';
		}

		if (beg > -1 && can && c === ')') {
			n = val.charAt(beg - 1);
			callback(val.substring(beg - (n === '!' ? 1 : 0), i + 1));
			can = false;
			find = false;
			beg = -1;
		}
	}
}

String.prototype.markdown = function(opt, nested) {

	// opt.wrap = true;
	// opt.linetag = 'p';
	// opt.ul = true;
	// opt.code = true;
	// opt.images = true;
	// opt.links = true;
	// opt.formatting = true;
	// opt.icons = true;
	// opt.tables = true;
	// opt.br = true;
	// opt.headlines = true;
	// opt.hr = true;
	// opt.blockquotes = true;
	// opt.sections = true;
	// opt.custom
	// opt.footnotes = true;
	// opt.urlify = true;
	// opt.keywords = true;
	// opt.emptynewline = true;
	// opt.bookmarks = true;
	// opt.prefix = '';

	var str = this;

	if (!opt)
		opt = {};

	if (opt.bookmarks == null)
		opt.bookmarks = true;

	var lines = str.split('\n');
	var builder = [];
	var ul = [];
	var table = false;
	var iscode = false;
	var isblock = false;
	var ishead = 0;
	var isprevblock = false;
	var headline = '<{0}' + (opt.bookmarks ? ' id="{3}"' : '') + ' class="markdown-line" data-index="{1}">{2}</{0}>';
	var line;
	var tmp;
	var prefix = opt.prefix || '';

	if (opt.wrap == null)
		opt.wrap = true;

	if (opt.linetag == null)
		opt.linetag = 'p';

	var closeul = function() {
		while (ul.length) {
			var text = ul.pop();
			builder.push('</' + text + '>');
		}
	};

	var linkreplace = function(text, inline) {
		if (inline)
			opt.$line = opt.$line.replace(text, markdown_links2);
		else if (opt.images !== false)
			opt.$line = opt.$line.replace(text, markdown_imagelinks);
		else
			opt.$line = opt.$line.replace(text, text => markdown_links(text, opt.images));
	};

	for (var i = 0; i < lines.length; i++) {

		lines[i] = lines[i].replace(REG_ENCODETAGS, ENCODE);

		if (!lines[i]) {
			builder.push('');
			continue;
		}

		var three = lines[i].substring(0, 3);

		if (!iscode && (three === ':::' || (three === '==='))) {

			if (isblock) {
				if (opt.blocks !== false)
					builder[builder.length - 1] += '</div></div>';
				isblock = false;
				isprevblock = true;
				continue;
			}

			closeul();
			isblock = true;
			if (opt.blocks !== false) {
				line = lines[i].substring(3).trim();
				if (opt.formatting !== false)
					line = formatline(line);
				if (opt.custom)
					line = opt.custom(line);
				if (opt.html)
					line = opt.html(line, 'block');
				builder.push('<div class="markdown-block markdown-line" data-line="{0}"><span class="markdown-showblock"><i class="ti ti-plus"></i>{1}</span><div class="hidden">'.format(i, line));
			}
			continue;
		}

		if (!isblock && lines[i] && isprevblock) {
			builder.push('<br />');
			isprevblock = false;
		}

		if (three === '```') {

			if (iscode) {
				if (opt.code !== false)
					builder[builder.length - 1] += '</code></pre></div>';
				iscode = false;
				continue;
			}

			closeul();
			iscode = true;
			if (opt.code !== false)
				tmp = '<div class="markdown-code markdown-line hidden"><pre class="noscrollbar"><code class="lang-{0}">'.format(lines[i].substring(3));
			continue;
		}

		if (iscode) {
			if (opt.code !== false)
				builder.push(tmp + lines[i]);
			if (tmp)
				tmp = '';
			continue;
		}

		line = lines[i];

		if (opt.br !== false)
			line = line.replace(/&lt;br(\s\/)?&gt;/g, '<br />');

		if (line.length > 10 && opt.urlify !== false && opt.links !== false)
			line = markdown_urlify(line);

		if (opt.custom)
			line = opt.custom(line);

		if (line.length > 2 && line !== '***' && line !== '---') {

			if (opt.formatting !== false)
				line = formatline(line);

			if (opt.images !== false)
				line = imagescope(line);

			if (opt.links !== false) {
				opt.$line = line;
				linkscope(line, 0, linkreplace);
				line = opt.$line;
			}

			if (opt.keywords !== false)
				line = line.replace(REG_KEYWORDS, markdown_keywords);

			if (opt.icons !== false)
				line = line.replace(REG_ICONS, markdown_icon);
		}

		if (!line) {
			if (table) {
				table = null;
				if (opt.tables !== false)
					builder.push('</tbody></table>');
			}
		}

		if (line === '' && lines[i - 1] === '') {
			closeul();
			if (opt.emptynewline !== false)
				builder.push('<br />');
			continue;
		}

		if (line[0] === '|') {
			closeul();

			if (!table) {
				var next = lines[i + 1];
				if (next[0] === '|') {
					if (next.indexOf('--') === -1) {
						if (opt.tables !== false)
							builder.push('<table class="table table-bordered"><thead>');
						table = [];
						ishead = 2;
					} else {
						table = [];
						var columns = next.substring(1, next.length - 1).split('|');
						for (var j = 0; j < columns.length; j++) {
							var column = columns[j].trim();
							var align = 'left';
							if (column.charAt(column.length - 1) === ':')
								align = column[0] === ':' ? 'center' : 'right';
							table.push(align);
						}
						if (opt.tables !== false)
							builder.push('<table class="table table-bordered"><thead>');
						ishead = 1;
						i++;
					}
				} else
					continue;
			}

			if (opt.tables !== false) {
				if (ishead === 1)
					builder.push(markdown_table(line, table, true) + '</thead><tbody>');
				else if (ishead === 2)
					builder.push('<tbody>' + markdown_table(line, table));
				else
					builder.push(markdown_table(line, table));
			}

			ishead = 0;
			continue;
		}

		if (line.charAt(0) === '#') {

			closeul();

			if (line.substring(0, 2) === '# ') {
				tmp = line.substring(2).trim();
				if (opt.headlines !== false) {
					if (opt.html)
						tmp = opt.html(tmp, '#');
					builder.push(headline.format('h1', i, tmp, opt.bookmarks ? markdown_id(prefix, tmp) : ''));
				}
				continue;
			}

			if (line.substring(0, 3) === '## ') {
				tmp = line.substring(3).trim();
				if (opt.headlines !== false) {
					if (opt.html)
						tmp = opt.html(tmp, '##');
					builder.push(headline.format('h2', i, tmp, opt.bookmarks ? markdown_id(prefix, tmp) : ''));
				}
				continue;
			}

			if (line.substring(0, 4) === '### ') {
				tmp = line.substring(4).trim();
				if (opt.headlines !== false) {
					if (opt.html)
						tmp = opt.html(tmp, '###');
					builder.push(headline.format('h3', i, tmp, opt.bookmarks ? markdown_id(prefix, tmp) : ''));
				}
				continue;
			}

			if (line.substring(0, 5) === '#### ') {
				tmp = line.substring(5).trim();
				if (opt.headlines !== false) {
					if (opt.html)
						tmp = opt.html(tmp, '####');
					builder.push(headline.format('h4', i, tmp, opt.bookmarks ? markdown_id(prefix, tmp) : ''));
				}
				continue;
			}

			if (line.substring(0, 6) === '##### ') {
				tmp = line.substring(6).trim();
				if (opt.headlines !== false) {
					if (opt.html)
						tmp = opt.html(tmp, '#####');
					builder.push(headline.format('h5', i, tmp, opt.bookmarks ? markdown_id(prefix, tmp) : ''));
				}
				continue;
			}
		}

		tmp = line.substring(0, 3);

		if (tmp === '---' || tmp === '***') {
			if (opt.hr !== false)
				builder.push('<hr class="markdown-line' + (tmp.charAt(0) === '-' ? '1' : '2') + ' markdown-line" data-line="' + i + '" />');
			continue;
		}

		// footnotes
		if ((/^#\d+:(\s)+/).test(line)) {
			if (opt.footnotes !== false) {
				tmp = line.indexOf(':');
				builder.push('<div class="markdown-footnotebody" data-id="{0}"><span>{0}:</span> {1}</div>'.format(line.substring(1, tmp).trim(), line.substring(tmp + 1).trim()));
			}
			continue;
		}

		if (line.substring(0, 5) === '&gt; ') {
			if (opt.blockquotes !== false) {
				line = line.substring(5).trim();
				if (opt.html)
					line = opt.html(line, 'blockquote');
				builder.push('<blockquote class="markdown-line" data-line="' + i + '">' + line + '</blockquote>');
			}
			continue;
		}

		if (line.substring(0, 5) === '&lt; ') {
			if (opt.sections !== false) {
				line = line.substring(5).trim();
				if (opt.html)
					line = opt.html(line, 'section');
				builder.push('<section class="markdown-line" data-line="' + i + '">' + line + '</section>');
			}
			continue;
		}

		var tmpline = line.trim();

		if (opt.ul !== false && REG_ORDERED.test(tmpline)) {

			var size = line.match(REG_ORDEREDSIZE);
			if (size)
				size = size[0].length;
			else
				size = 0;

			var c = tmpline.charAt(0);
			var ultype = c === '-' || c === '*' || c === '+' ? 'ul' : 'ol';
			var tmpstr = (ultype === 'ol' ? tmpline.substring(tmpline.indexOf('.') + 1) : tmpline.substring(2));
			var istask = false;

			var tt = tmpstr.trim().substring(0, 3);
			istask = tt === '[ ]' || tt === '[x]';

			var tmpval = tmpstr.trim();

			if (opt.html)
				tmpval = opt.html(tmpval, 'li');

			builder.push('\0' + (ultype === 'ol' ? ('o' + ((/\d+\./).test(tmpline) ? '1' : 'a')) : 'ul') + size + '<li data-line="{0}" class="markdown-line{1}">'.format(i, istask ? ' markdown-task' : '') + tmpval.replace(/\[x\]/g, '<i class="ti ti-check-square green"></i>').replace(/\[\s\]/g, '<i class="ti ti-square"></i>') + '</li>');

		} else {
			closeul();
			if (line) {
				line = line.trim();
				if (opt.html)
					line = opt.html(line, opt.linetag);
			}
			line && builder.push((opt.linetag ? ('<' + opt.linetag + ' class="markdown-line" data-line="' + i +  '">') : '') + line.trim() + (opt.linetag ? ('</' + opt.linetag + '>') : ''));
		}
	}

	closeul();

	table && opt.tables !== false && builder.push('</tbody></table>');
	iscode && opt.code !== false && builder.push('</code></pre>');

	builder = parseul(builder);
	return (opt.wrap ? ('<div class="markdown' + (nested ? '' : ' markdown-container') + '">') : '') + builder.join('\n').replace(/\t/g, '    ') + (opt.wrap ? '</div>' : '');
};