Fix nyaize 2 (#5841)

* Korean, English Nyaziation and special case exclusion

* Remove single en and unused

* order of exclude

* nl

* code style

src/misc/nyaize.ts

@@ -1,13 +1,46 @@
+import rndstr from 'rndstr';
+
 export function nyaize(text: string): string {
-	return text
+	const [toNyaize, exclusionMap] = exclude(text);
+	const nyaized = toNyaize
 		// ja-JP
 		.replace(/な/g, 'にゃ').replace(/ナ/g, 'ニャ').replace(/ﾅ/g, 'ﾆｬ')
 		// en-US
 		.replace(/morning/gi, 'mornyan').replace(/everyone/gi, 'everynyan')
 		// ko-KR
 		.replace(/[나-낳]/g, match => String.fromCharCode(
-			match.codePointAt(0)! + '냐'.charCodeAt(0) - '나'.charCodeAt(0)
+			match.charCodeAt(0)! + '냐'.charCodeAt(0) - '나'.charCodeAt(0)
 		))
 		.replace(/(다$)|(다(?=\.))|(다(?= ))|(다(?=!))|(다(?=\?))/gm, '다냥')
 		.replace(/(야(?=\?))|(야$)|(야(?= ))/gm, '냥');
+	return replaceExceptions(nyaized, exclusionMap);
+}
+
+function exclude(text: string): [string, Record<string, string>] {
+	const map: Record<string, string> = {};
+	function substitute(match: string): string {
+		let randomstr: string;
+		do {
+			randomstr = rndstr({ length: 16, chars: '🀀-🀫' });
+		} while(Object.prototype.hasOwnProperty.call(map, randomstr));
+		map[randomstr] = match;
+		return randomstr;
+	}
+	const replaced = text
+		.replace(/```(.+?)?\n([\s\S]+?)```(\n|$)/gm, match => substitute(match)) // code block
+		.replace(/`([^`\n]+?)`/g, match => substitute(match)) // inline code
+		.replace(/(https?:\/\/.*?)(?= |$)/gm, match => substitute(match)) // URL
+		.replace(/:([a-z0-9_+-]+):/gim, match => substitute(match)) // emoji
+		.replace(/#([^\s.,!?'"#:\/\[\]【】]+)/gm, match => substitute(match)) // hashtag
+		.replace(/@\w([\w-]*\w)?(?:@[\w.\-]+\w)?/gm, match => substitute(match)); // mention
+	return [replaced, map];
+}
+
+function replaceExceptions(text: string, map: Record<string, string>): string {
+	for (const rule in map) {
+		if (Object.prototype.hasOwnProperty.call(map, rule)) {
+			text = text.replace(rule, map[rule]);
+		}
+	}
+	return text;
 }