feat(service): prefer recently/often used applications in search

service/src/priority.rs

@@ -0,0 +1,59 @@
+use std::cmp::Ordering;
+
+use crate::PluginPriority;
+
+
+// holds all values used for ordering search results
+pub struct Priority {
+    pub plugin_priority: PluginPriority,
+    pub match_score: f64,
+    pub recent_use_index: usize,
+    pub use_freq: usize,
+    pub execlen: usize,
+}
+
+
+fn signum(val: i32) -> f64 {
+    if val > 0 { return  1.0; }
+    if val < 0 { return -1.0; }
+    0.0
+}
+
+impl Priority {
+    fn compute_value(&self, other: &Self) -> f64{
+        // increases compared jw-score if this search result
+        // was activated more frequent or recent by constant values
+        let score = self.match_score
+            + 0.06 * signum(self.recent_use_index as i32 - other.recent_use_index as i32)
+            + 0.03 * signum(self.use_freq as i32 - other.use_freq as i32);
+        // score cannot surpass exact matches
+        if self.match_score < 1.0 {
+            return score.min(0.99);
+        }
+        return score;
+    }
+}
+
+impl PartialEq for Priority {
+    fn eq(&self, other: &Self) -> bool {        
+        self.plugin_priority == other.plugin_priority
+            && self.compute_value(other) == other.match_score
+            && self.execlen == other.execlen
+    }
+}
+
+impl Eq for Priority {}
+
+impl PartialOrd for Priority {
+    fn partial_cmp(&self, other: &Self) -> Option<Ordering> {        
+        (other.plugin_priority, self.compute_value(other), self.execlen).partial_cmp(
+            &(self.plugin_priority, other.match_score, other.execlen)
+        )
+    }
+}
+
+impl Ord for Priority {
+    fn cmp(&self, other: &Self) -> Ordering {
+        self.partial_cmp(other).unwrap()
+    }
+}