format currency with 2 pence digits and thousands separators

1 files changed, 21 insertions, 2 deletions

diff --git a/schist_desktop_gui/src/gui/components/text.rs b/schist_desktop_gui/src/gui/components/text.rs
index 068e89a..30aab8d 100644
--- a/schist_desktop_gui/src/gui/components/text.rs
+++ b/schist_desktop_gui/src/gui/components/text.rs
@@ -79,10 +79,13 @@ impl Text {
     }
 
     pub fn currency(amount: i32) -> Self {
+        let abs_amount = amount.unsigned_abs();
+        let pounds = separate_thousands(abs_amount / 100, " ");
+        let pence = abs_amount % 100;
         let formatted_string = if amount < 0 {
-            format!("({} · {})", -amount / 100, -amount % 100)
+            format!("({pounds} · {pence:02})")
         } else {
-            format!(" {} · {} ", amount / 100, amount % 100)
+            format!(" {pence} · {pence:02} ")
         };
         Self::default(&formatted_string)
     }
@@ -247,3 +250,19 @@ where
 }
 
 impl_focusable!(Text);
+
+fn separate_thousands(n: u32, separator: &str) -> String {
+    if n == 0 {
+        return String::from("0");
+    }
+
+    let mut result = String::new();
+    let mut dividend = n;
+    while dividend > 0 {
+        let remainder = dividend % 1000;
+        result = format!("{remainder:03}{separator}{result}");
+        dividend = dividend / 1000;
+    }
+
+    result.trim_start_matches("0").to_string()
+}