Detect highlights

lib/irc.js

@@ -196,3 +196,47 @@ export function parseMembership(s) {
 		nick: s.slice(i),
 	};
 }
+
+const alphaNum = (() => {
+	try {
+		return new RegExp(/^\p{L}$/, "u");
+	} catch (e) {
+		return new RegExp(/^[a-zA-Z0-9]$/, "u");
+	}
+})();
+
+function isWordBoundary(ch) {
+	switch (ch) {
+	case "-":
+	case "_":
+	case "|":
+		return false;
+	case "\u00A0":
+		return true;
+	default:
+		return !alphaNum.test(ch);
+	}
+}
+
+export function isHighlight(text, nick) {
+	while (true) {
+		var i = text.indexOf(nick);
+		if (i < 0) {
+			return false;
+		}
+
+		// Detect word boundaries
+		var left = "\x00", right = "\x00";
+		if (i > 0) {
+			left = text[i - 1];
+		}
+		if (i < text.length) {
+			right = text[i + nick.length];
+		}
+		if (isWordBoundary(left) && isWordBoundary(right)) {
+			return true;
+		}
+
+		text = text.slice(i + nick.length);
+	}
+}