feat: SI prefixed sats amounts

Author: elsirion

src/templates/donate.rs

@@ -1,3 +1,4 @@
+use super::format_sats_si;
 use crate::models::Donation;
 use crate::templates::components::{
     donation_invoice_markup, donation_invoice_script, DonationInvoiceConfig,
@@ -40,7 +41,7 @@ pub fn donate(
             div class="text-center mt-8" {
                 div class="stat-brutal" {
                     div class="stat-value orange" {
-                        (pool_balance_sats) " "
+                        (format_sats_si(pool_balance_sats)) " "
                         i class="fa-solid fa-bolt" {}
                     }
                     div class="stat-label" { "sats split across " (num_locations) " locations" }
@@ -96,7 +97,7 @@ pub fn donate(
                                         }
                                     }
                                     td class="py-2 px-3 text-right font-bold text-highlight orange" {
-                                        (donation.amount_sats()) " "
+                                        (format_sats_si(donation.amount_sats())) " "
                                         i class="fa-solid fa-bolt" {}
                                     }
                                 }

src/templates/home.rs

@@ -1,3 +1,4 @@
+use super::format_sats_si;
 use crate::models::Stats;
 use maud::{html, Markup};
 
@@ -35,7 +36,7 @@ pub fn home(stats: &Stats) -> Markup {
             ))
             (stat_card(
                 "Sats Available",
-                &format!("{}", stats.total_sats_available),
+                &format_sats_si(stats.total_sats_available),
                 true,
                 "fa-bolt"
             ))
@@ -128,3 +129,33 @@ fn step(number: &str, title: &str, description: &str) -> Markup {
         }
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn test_format_sats_si() {
+        // Zero and negative
+        assert_eq!(format_sats_si(0), "0");
+        assert_eq!(format_sats_si(-100), "0");
+
+        // Small values (no suffix)
+        assert_eq!(format_sats_si(1), "1");
+        assert_eq!(format_sats_si(999), "999");
+
+        // Thousands (k suffix) - 3 significant figures
+        assert_eq!(format_sats_si(1000), "1.00k");
+        assert_eq!(format_sats_si(2310), "2.31k");
+        assert_eq!(format_sats_si(21400), "21.4k");
+        assert_eq!(format_sats_si(256000), "256k");
+        assert_eq!(format_sats_si(999_499), "999k");
+        assert_eq!(format_sats_si(999_500), "1.00M");
+
+        // Millions (M suffix) - 3 significant figures
+        assert_eq!(format_sats_si(1_000_000), "1.00M");
+        assert_eq!(format_sats_si(1_230_000), "1.23M");
+        assert_eq!(format_sats_si(21_000_000), "21.0M");
+        assert_eq!(format_sats_si(123_000_000), "123M");
+    }
+}

src/templates/location_detail.rs

@@ -1,3 +1,4 @@
+use super::format_sats_si;
 use crate::models::{Donation, Location, NfcCard, Photo, ScanWithUser, UserRole};
 use crate::templates::components::{
     donation_invoice_markup, donation_invoice_script, DonationInvoiceConfig,
@@ -243,14 +244,14 @@ pub fn location_detail(
                     div class="card-brutal-inset p-4" {
                         div class="label-brutal text-xs mb-2" { "AVAILABLE SATS" }
                         div class="text-2xl font-black text-highlight orange" {
-                            (available_sats) " "
+                            (format_sats_si(available_sats)) " "
                             i class="fa-solid fa-bolt" {}
                         }
                     }
                     div class="card-brutal-inset p-4" {
                         div class="label-brutal text-xs mb-2" { "POOL BALANCE" }
                         div class="text-2xl font-black text-secondary" {
-                            (pool_sats) " "
+                            (format_sats_si(pool_sats)) " "
                             i class="fa-solid fa-bolt" {}
                         }
                     }
@@ -361,7 +362,7 @@ pub fn location_detail(
                         div {
                             div class="label-brutal text-xs mb-1" { "POOL BALANCE" }
                             div class="text-3xl font-black text-highlight orange" {
-                                (pool_sats) " "
+                                (format_sats_si(pool_sats)) " "
                                 i class="fa-solid fa-bolt" {}
                             }
                         }
@@ -431,7 +432,7 @@ pub fn location_detail(
                                             }
                                             td class="py-3 px-4 text-right mono" {
                                                 span class="text-highlight orange font-black" {
-                                                    (donation.amount_sats())
+                                                    (format_sats_si(donation.amount_sats()))
                                                 }
                                                 " "
                                                 i class="fa-solid fa-bolt text-highlight orange" {}
@@ -475,7 +476,7 @@ pub fn location_detail(
                                         td class="py-3 px-4 text-right" {
                                             @if scan.is_claimed() {
                                                 span class="text-highlight orange font-black" {
-                                                    (scan.sats_claimed())
+                                                    (format_sats_si(scan.sats_claimed()))
                                                     " "
                                                     i class="fa-solid fa-bolt" {}
                                                 }
@@ -623,7 +624,7 @@ pub fn location_detail(
         "#,
             location.longitude, location.latitude,
             location.longitude, location.latitude,
-            location.name, available_sats
+            location.name, format_sats_si(available_sats)
         )))
 
         // Photo upload script - auto-upload on file selection

src/templates/mod.rs

@@ -14,6 +14,33 @@ pub mod register;
 pub mod wallet;
 pub mod withdraw;
 
+/// Format sats with SI prefixes (k, M) and 3 significant figures
+pub fn format_sats_si(sats: i64) -> String {
+    if sats <= 0 {
+        return "0".to_string();
+    }
+    let sats = sats as f64;
+
+    let (val, suffix) = if sats >= 1_000_000.0 {
+        (sats / 1_000_000.0, "M")
+    } else if sats >= 1_000.0 {
+        (sats / 1_000.0, "k")
+    } else {
+        return (sats as u64).to_string();
+    };
+
+    // Round to 3 significant figures
+    let decimals = if val >= 100.0 { 0 } else if val >= 10.0 { 1 } else { 2 };
+    let formatted = format!("{:.decimals$}{suffix}", val);
+
+    // Handle rounding up to next unit (e.g., 999.9k -> 1000k should be 1M)
+    if formatted.starts_with("1000") && suffix == "k" {
+        "1.00M".to_string()
+    } else {
+        formatted
+    }
+}
+
 pub use admin_locations::admin_locations;
 pub use admin_users::admin_users;
 pub use collect::{collect, CollectParams};