time: add future timestamp formatting

+10s for 10 seconds in the future, etc

This can happen sometimes

Signed-off-by: William Casarin <jb55@jb55.com>

src/time.rs

@@ -1,46 +1,54 @@
 use std::time::{SystemTime, UNIX_EPOCH};
 
-/// Show a relative time string based on some timestamp
 pub fn time_ago_since(timestamp: u64) -> String {
     let now = SystemTime::now()
         .duration_since(UNIX_EPOCH)
         .expect("Time went backwards")
         .as_secs();
-    let duration = now.saturating_sub(timestamp);
+
+    // Determine if the timestamp is in the future or the past
+    let duration = if now >= timestamp {
+        now.saturating_sub(timestamp)
+    } else {
+        timestamp.saturating_sub(now)
+    };
+
+    let future = timestamp > now;
+    let relstr = if future { "+" } else { "" };
 
     let years = duration / 31_536_000; // seconds in a year
     if years >= 1 {
-        return format!("{}yr", years);
+        return format!("{}{}yr", relstr, years);
     }
 
     let months = duration / 2_592_000; // seconds in a month (30.44 days)
     if months >= 1 {
-        return format!("{}mth", months);
+        return format!("{}{}mth", relstr, months);
     }
 
     let weeks = duration / 604_800; // seconds in a week
     if weeks >= 1 {
-        return format!("{}wk", weeks);
+        return format!("{}{}wk", relstr, weeks);
     }
 
     let days = duration / 86_400; // seconds in a day
     if days >= 1 {
-        return format!("{}d", days);
+        return format!("{}{}d", relstr, days);
     }
 
     let hours = duration / 3600; // seconds in an hour
     if hours >= 1 {
-        return format!("{}h", hours);
+        return format!("{}{}h", relstr, hours);
     }
 
     let minutes = duration / 60; // seconds in a minute
     if minutes >= 1 {
-        return format!("{}m", minutes);
+        return format!("{}{}m", relstr, minutes);
     }
 
     let seconds = duration;
     if seconds >= 3 {
-        return format!("{}s", seconds);
+        return format!("{}{}s", relstr, seconds);
     }
 
     "now".to_string()