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

Cargo.lock

@@ -1122,6 +1122,7 @@ dependencies = [
  "anyhow",
  "async-oneshot",
  "async-trait",
+ "dirs 4.0.0",
  "flume",
  "futures",
  "futures_codec",

service/Cargo.toml

@@ -8,6 +8,7 @@ edition = "2018"
 anyhow = "1.0.56"
 async-oneshot = "0.5.0"
 async-trait = "0.1.53"
+dirs = "4.0.0"
 futures = "0.3.21"
 futures_codec = "0.4.1"
 gen-z = "0.1.0"

service/src/lib.rs

@@ -3,12 +3,16 @@
 
 mod client;
 mod plugins;
+mod recent;
+mod priority;
 
 pub use client::*;
 pub use plugins::config;
 pub use plugins::external::load;
 
 use crate::plugins::*;
+use crate::recent::RecentUseStorage;
+use crate::priority::Priority;
 use flume::{Receiver, Sender};
 use futures::{future, SinkExt, Stream, StreamExt};
 use pop_launcher::*;
@@ -16,7 +20,7 @@ use regex::Regex;
 use slab::Slab;
 use std::{
     collections::{HashMap, HashSet},
-    io::{self, Write},
+    io::{self, Write}, path::PathBuf,
 };
 
 pub type PluginKey = usize;
@@ -34,7 +38,38 @@ pub struct PluginHelp {
     pub help: Option<String>,
 }
 
+
+pub fn ensure_cache_path() -> Result<PathBuf, Box<dyn std::error::Error>> {
+    let cachepath = dirs::home_dir().ok_or("failed to find home dir")?.join(".cache/pop-launcher");
+    std::fs::create_dir_all(&cachepath)?;
+    Ok(cachepath.join("recent"))
+}
+
+pub fn store_cache(storage: &RecentUseStorage) {
+    let write_recent = || -> Result<(), Box<dyn std::error::Error>> {
+        let cachepath = ensure_cache_path()?;
+        Ok(serde_json::to_writer(
+            std::fs::File::create(cachepath)?,
+            storage
+        )?)
+    };
+    if let Err(e)= write_recent() {
+        eprintln!("could not write to cache file\n{}", e);
+    }
+}
+
 pub async fn main() {
+    let cachepath = ensure_cache_path();
+    let read_recent = || -> Result<RecentUseStorage, Box<dyn std::error::Error>> {
+        let cachepath = std::fs::File::open(cachepath?)?;
+        Ok(serde_json::from_reader(cachepath)?)
+    };
+    let recent = match read_recent() {
+        Ok(r) => r,
+        Err(e) => {eprintln!("could not read cache file\n{}", e); RecentUseStorage::default()}
+    };
+    
+
     // Listens for a stream of requests from stdin.
     let input_stream = json_input_stream(tokio::io::stdin()).filter_map(|result| {
         future::ready(match result {
@@ -49,7 +84,7 @@ pub async fn main() {
     let (output_tx, output_rx) = flume::bounded(16);
 
     // Service will operate for as long as it is being awaited
-    let service = Service::new(output_tx.into_sink()).exec(input_stream);
+    let service = Service::new(output_tx.into_sink(), recent).exec(input_stream);
 
     // Responses from the service will be streamed to stdout
     let responder = async move {
@@ -73,10 +108,11 @@ pub struct Service<O> {
     output: O,
     plugins: Slab<PluginConnector>,
     search_scheduled: bool,
+    recent: RecentUseStorage,
 }
 
 impl<O: futures::Sink<Response> + Unpin> Service<O> {
-    pub fn new(output: O) -> Self {
+    pub fn new(output: O, recent: RecentUseStorage) -> Self {
         Self {
             active_search: Vec::new(),
             associated_list: HashMap::new(),
@@ -86,6 +122,7 @@ impl<O: futures::Sink<Response> + Unpin> Service<O> {
             no_sort: false,
             plugins: Slab::new(),
             search_scheduled: false,
+            recent,
         }
     }
 
@@ -241,16 +278,24 @@ impl<O: futures::Sink<Response> + Unpin> Service<O> {
     }
 
     async fn activate(&mut self, id: Indice) {
+        let mut ex = None;
         if let Some((plugin, meta)) = self.search_result(id as usize) {
+            ex = meta.cache_identifier();
             let _ = plugin
                 .sender_exec()
                 .send_async(Request::Activate(meta.id))
                 .await;
         }
+        if let Some(e) = ex {
+            self.recent.add(&e);
+            store_cache(&self.recent);
+        }
     }
 
     async fn activate_context(&mut self, id: Indice, context: Indice) {
+        let mut ex = None;
         if let Some((plugin, meta)) = self.search_result(id as usize) {
+            ex = meta.cache_identifier();
             let _ = plugin
                 .sender_exec()
                 .send_async(Request::ActivateContext {
@@ -259,6 +304,10 @@ impl<O: futures::Sink<Response> + Unpin> Service<O> {
                 })
                 .await;
         }
+        if let Some(e) = ex {
+            self.recent.add(&e);
+            store_cache(&self.recent);
+        }
     }
 
     fn append(&mut self, plugin: PluginKey, append: PluginSearchResult) {
@@ -445,6 +494,7 @@ impl<O: futures::Sink<Response> + Unpin> Service<O> {
             ref mut no_sort,
             ref last_query,
             ref plugins,
+            ref recent,
             ..
         } = self;
 
@@ -497,23 +547,6 @@ impl<O: futures::Sink<Response> + Unpin> Service<O> {
                         })
                 }
 
-                let a_weight = calculate_weight(&a.1, query);
-                let b_weight = calculate_weight(&b.1, query);
-
-                match a_weight.partial_cmp(&b_weight) {
-                    Some(Ordering::Equal) => {
-                        let a_len = a.1.name.len();
-                        let b_len = b.1.name.len();
-
-                        a_len.cmp(&b_len)
-                    }
-                    Some(Ordering::Less) => Ordering::Greater,
-                    Some(Ordering::Greater) => Ordering::Less,
-                    None => Ordering::Greater,
-                }
-            });
-
-            active_search.sort_by(|a, b| {
                 let plug1 = match plugins.get(a.0) {
                     Some(plug) => plug,
                     None => return Ordering::Greater,
@@ -524,11 +557,18 @@ impl<O: futures::Sink<Response> + Unpin> Service<O> {
                     None => return Ordering::Less,
                 };
 
-                plug1
+                let get_prio = |sr: &PluginSearchResult, plg: &PluginConnector| -> Priority {
-                    .config
+                    let ex = sr.cache_identifier();
-                    .query
+                    Priority {
-                    .priority
+                        plugin_priority: plg.config.query.priority,
-                    .cmp(&plug2.config.query.priority)
+                        match_score: calculate_weight(sr, query),
+                        recent_use_index: ex.as_ref().map(|s| recent.get_recent(s)).unwrap_or(0),
+                        use_freq: ex.as_ref().map(|s| recent.get_freq(s)).unwrap_or(0),
+                        execlen: sr.name.len()
+                    }
+                };
+                
+                get_prio(&b.1, plug2).cmp(&get_prio(&a.1, plug1))
             })
         }
 

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()
+    }
+}

service/src/recent.rs

@@ -0,0 +1,90 @@
+use std::collections::{HashMap, hash_map::DefaultHasher};
+use std::hash::{Hasher, Hash};
+use serde::{Deserialize, Serialize, Serializer, Deserializer};
+
+const SHORTTERM_CAP: usize = 20;
+const LONGTERM_CAP: usize = 100;
+
+// Holds a long term storage that tracks how often a search
+// result was activated, and a short term storage that stores
+// the order of recently activated search results (higher
+// vales are more recent).
+// Keys for both mappings are hashes of the acvtivated result's
+// command string.
+#[derive(Debug, Default)]
+pub struct RecentUseStorage {
+    long_term: HashMap<usize, usize>,
+    short_term: HashMap<usize, usize>,
+}
+
+
+fn hash_key<K: Hash>(key: K) -> usize {
+    let mut hasher = DefaultHasher::new();
+    key.hash(&mut hasher);
+    hasher.finish() as usize
+}
+
+
+impl RecentUseStorage {
+    pub fn add<K: Hash>(&mut self, exec: &K) {
+        let key = hash_key(exec);
+        *self.long_term.entry(key).or_insert(0) += 1;
+        let short_term_idx = self.short_term.values().max().unwrap_or( &0)+1;
+        self.short_term.insert(key, short_term_idx);
+        self.trim()
+    }
+
+    fn trim(&mut self) {
+        while self.short_term.len() > SHORTTERM_CAP {
+            let key = *self.short_term.iter().min_by_key(|kv| kv.1).unwrap().0;
+            self.short_term.remove(&key);
+        }
+
+        while self.long_term.values().sum::<usize>() > LONGTERM_CAP {
+            let mut delete_keys = Vec::new();
+            for (k, v) in self.long_term.iter_mut() {
+                *v /= 2;
+                if *v == 0 {
+                    delete_keys.push(*k);
+                }
+            }
+            for k in delete_keys {
+                self.long_term.remove(&k);
+            }
+        }
+    }
+
+    pub fn get_recent<K: Hash>(&self, exec: &K) -> usize {
+        self.short_term.get(&hash_key(exec)).copied().unwrap_or(0)
+    }
+
+    pub fn get_freq<K: Hash>(&self, exec: &K) -> usize {
+        self.long_term.get(&hash_key(exec)).copied().unwrap_or(0)
+    }
+}
+
+impl Serialize for RecentUseStorage {
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        let mut stvec: Vec<_> = self.short_term.keys().copied().collect();
+        stvec.sort_by_key(|k| self.short_term[k]);
+        (&self.long_term, stvec).serialize(serializer)
+    }
+}
+
+impl<'de> Deserialize<'de> for RecentUseStorage {
+    fn deserialize<D>(deserializer: D) -> Result<RecentUseStorage, D::Error>
+    where
+        D: Deserializer<'de>,
+    {
+        type SerType = (HashMap<usize, usize>, Vec<usize>);
+        let (long_term, stv) = SerType::deserialize(deserializer)?;
+        let short_term: HashMap<_, _> = stv.into_iter().enumerate().map(|(v,k)| (k,v)).collect();
+        Ok(RecentUseStorage {
+            long_term,
+            short_term,
+        })
+    }
+}

src/lib.rs

@@ -110,6 +110,15 @@ pub struct PluginSearchResult {
     pub window: Option<(Generation, Indice)>,
 }
 
+impl PluginSearchResult {
+    pub fn cache_identifier(&self) -> Option<String> {
+        // the exec field may clash in multiple search results as the arguments
+        // are cut from the string
+        // self.exec.to_owned().unwrap_or_else(|| self.name.to_owned())
+        self.exec.as_ref().map(|_| self.name.to_owned())
+    }
+}
+
 // Sent to the input pipe of the launcher service, and disseminated to its plugins.
 #[derive(Debug, Deserialize, Serialize, Clone)]
 pub enum Request {