Add ban command

src/utils.rs

@@ -100,3 +100,32 @@ pub fn i64_to_u64(i: i64) -> u64 {
 pub fn u64_to_i64(u: u64) -> i64 {
     i64::from_ne_bytes(u.to_ne_bytes())
 }
+
+/// Splits at the `n`th occurrence of `pattern` counting from the end of the string.
+/// 
+/// Arguments:
+/// * `s` - The string to split.
+/// * `pattern` - The pattern to split at.
+/// * `n` - The occurrence to split at (counting from the end).
+/// 
+/// Returns:
+/// [`Option<(&str, &str)>`] - The splitted parts of the string, or [`None`] if no occurrences of
+/// `pattern` were found in `s`.
+pub fn split_at_nth_from_end<'a, 'b>(s: &'a str, pattern: &'b str, n: usize) -> Option<(&'a str, &'a str)> {
+    let mut end = s.len();
+    let mut count = 0;
+
+    while let Some(pos) = s[..end].rfind(pattern) {
+        count += 1;
+
+        if count == n {
+            let before = &s[..pos];
+            let after = &s[pos + pattern.len()..];
+            return Some((before, after));
+        }
+
+        end = pos; // move left and keep searching
+    }
+
+    None
+}