perf(search): benchmark smart sort (#2202)

2 files changed, 47 insertions, 0 deletions

diff --git a/crates/atuin-history/src/lib.rs b/crates/atuin-history/src/lib.rs
index 9d34677f..e7b33916 100644
--- a/crates/atuin-history/src/lib.rs
+++ b/crates/atuin-history/src/lib.rs
@@ -1 +1,2 @@
+pub mod sort;
 pub mod stats;
diff --git a/crates/atuin-history/src/sort.rs b/crates/atuin-history/src/sort.rs
new file mode 100644
index 00000000..4465a142
--- /dev/null
+++ b/crates/atuin-history/src/sort.rs
@@ -0,0 +1,46 @@
+use atuin_client::history::History;
+
+type ScoredHistory = (f64, History);
+
+// Fuzzy search already comes sorted by minspan
+// This sorting should be applicable to all search modes, and solve the more "obvious" issues
+// first.
+// Later on, we can pass in context and do some boosts there too.
+pub fn sort(query: &str, input: Vec<History>) -> Vec<History> {
+    // This can totally be extended. We need to be _careful_ that it's not slow.
+    // We also need to balance sorting db-side with sorting here. SQLite can do a lot,
+    // but some things are just much easier/more doable in Rust.
+
+    let mut scored = input
+        .into_iter()
+        .map(|h| {
+            // If history is _prefixed_ with the query, score it more highly
+            let score = if h.command.starts_with(query) {
+                2.0
+            } else if h.command.contains(query) {
+                1.75
+            } else {
+                1.0
+            };
+
+            // calculate how long ago the history was, in seconds
+            let now = time::OffsetDateTime::now_utc().unix_timestamp();
+            let time = h.timestamp.unix_timestamp();
+            let diff = std::cmp::max(1, now - time); // no /0 please
+
+            // prefer newer history, but not hugely so as to offset the other scoring
+            // the numbers will get super small over time, but I don't want time to overpower other
+            // scoring
+            #[allow(clippy::cast_precision_loss)]
+            let time_score = 1.0 + (1.0 / diff as f64);
+            let score = score * time_score;
+
+            (score, h)
+        })
+        .collect::<Vec<ScoredHistory>>();
+
+    scored.sort_by(|a, b| a.0.partial_cmp(&b.0).unwrap().reverse());
+
+    // Remove the scores and return the history
+    scored.into_iter().map(|(_, h)| h).collect::<Vec<History>>()
+}