Add OSC 8 hyperlink support

This commit adds support for the OSC 8 hyperlink escape sequence [1]. As
this is not a mature feature and there seem to be outstanding security
concerns [2], the setting that controls whether or not OSC 8 is
interpreted is disabled by default.

Just like gnome-terminal, weltschmerz will display a tooltip with the
canonicalized URI when hovering over a hyperlink.

[1] https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda
[2] https://gist.github.com/egmontkob/eb114294efbcd5adb1944c9f3cb5feda#security

1 files changed, 27 insertions, 0 deletions

diff --git a/utils.vala b/utils.vala
new file mode 100644
index 0000000..845728b
--- /dev/null
+++ b/utils.vala
@@ -0,0 +1,27 @@
+class Utils {
+	public static string? normalize_uri(string? uri) {
+		if (uri == null)
+			return null;
+
+		string? u = Uri.unescape_string(uri, null);
+
+		if (u == null)
+			u = uri;
+
+		if (u.has_prefix("ftp://") || u.has_prefix("http://") || u.has_prefix("https://")) {
+			int a = u.index_of("/", 0) + 2; // character after second slash
+			int b = u.index_of("/", a); // next slash after hostname...
+			if (b < 0)
+				b = u.length; // ... or end of string
+
+			string hostname = u.slice(a, b);
+			string? canon = Hostname.to_unicode(hostname);
+
+			if (canon != null && hostname != canon) {
+				u = u.splice(a, b, canon);
+			}
+		}
+
+		return u;
+	}
+}