Impl display for error

src/errors.rs

@@ -1,6 +1,23 @@
+use std::fmt;
+
 #[derive(Debug)]
 pub enum FBError {
 	DecodeError,
 	InvalidKey,
 	InvalidParams,
 }
+
+impl fmt::Display for FBError {
+
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        let message = match self {
+            FBError::DecodeError => "Invalid input",
+            FBError::InvalidKey => "Invalid Key used",
+            FBError::InvalidParams => "Keybase len(k) or Cipher len(n) out of bounds. Valid bounds: (2 <= k <= n)",
+        };
+
+        f.write_fmt(format_args!("{message}"))
+    }
+}
+
+impl std::error::Error for FBError {}