Include title in indexes to avoid a per-record disk read

GOTTA GO FAST

src/app_console/app_console.cpp

@@ -259,7 +259,7 @@ int CmdDbIndex(int argc, char** argv) {
   for (database::IndexRecord r : res->values()) {
     std::cout << r.text().value_or("<unknown>");
     if (r.track()) {
-      std::cout << "\t(id:" << r.track()->data().id() << ")";
+      std::cout << "\t(id:" << *r.track() << ")";
     }
     std::cout << std::endl;
   }

src/database/database.cpp

@@ -600,20 +600,12 @@ auto Database::ParseRecord<IndexRecord>(const leveldb::Slice& key,
     return {};
   }
 
-  // If there was a track id included for this key, then this is a leaf record.
-  // Fetch the actual track data instead of relying on the information in the
-  // key.
-  std::optional<Track> track;
-  if (data->track) {
-    std::optional<TrackData> track_data = dbGetTrackData(*data->track);
-    TrackTags track_tags;
-    if (track_data &&
-        tag_parser_->ReadAndParseTags(track_data->filepath(), &track_tags)) {
-      track.emplace(*track_data, track_tags);
-    }
+  std::optional<std::string> title;
+  if (!val.empty()) {
+    title = val.ToString();
   }
 
-  return IndexRecord(*data, track);
+  return IndexRecord(*data, title, data->track);
 }
 
 template <>
@@ -663,17 +655,17 @@ auto Database::ParseRecord<std::string>(const leveldb::Slice& key,
   return stream.str();
 }
 
-IndexRecord::IndexRecord(const IndexKey& key, std::optional<Track> track)
-    : key_(key), track_(track) {}
+IndexRecord::IndexRecord(const IndexKey& key, std::optional<shared_string> title, std::optional<TrackId> track)
+    : key_(key), override_text_(title), track_(track) {}
 
 auto IndexRecord::text() const -> std::optional<shared_string> {
-  if (track_) {
-    return track_->TitleOrFilename();
+  if (override_text_) {
+    return override_text_;
   }
   return key_.item;
 }
 
-auto IndexRecord::track() const -> std::optional<Track> {
+auto IndexRecord::track() const -> std::optional<TrackId> {
   return track_;
 }
 

src/database/include/database.hpp

@@ -70,16 +70,17 @@ class Result {
 
 class IndexRecord {
  public:
-  explicit IndexRecord(const IndexKey&, std::optional<Track>);
+   explicit IndexRecord(const IndexKey&, std::optional<shared_string>, std::optional<TrackId>);
 
   auto text() const -> std::optional<shared_string>;
-  auto track() const -> std::optional<Track>;
+  auto track() const -> std::optional<TrackId>;
 
   auto Expand(std::size_t) const -> std::optional<Continuation<IndexRecord>>;
 
  private:
   IndexKey key_;
-  std::optional<Track> track_;
+  std::optional<shared_string> override_text_;
+  std::optional<TrackId> track_;
 };
 
 class Database {

src/database/index.cpp

@@ -52,15 +52,20 @@ auto Index(const IndexInfo& info, const Track& t, leveldb::WriteBatch* batch)
       key.item = {};
     }
 
-    // If this is the last component, then we should also fill in the track id.
+    // If this is the last component, then we should also fill in the track id
+    // and title.
+    std::optional<std::string> title;
     if (i == info.components.size() - 1) {
       key.track = t.data().id();
+      if (info.components.at(i) != Tag::kTitle) {
+        title = t.TitleOrFilename();
+      }
     } else {
       key.track = {};
     }
 
     auto encoded = EncodeIndexKey(key);
-    batch->Put(encoded.slice, leveldb::Slice{});
+    batch->Put(encoded.slice, title.value_or(""));
 
     // If there are more components after this, then we need to finish by
     // narrowing the header with the current title.

src/ui/screen_track_browser.cpp

@@ -110,7 +110,6 @@ auto TrackBrowser::Tick() -> void {
   }
   if (loading_page_->wait_for(std::chrono::seconds(0)) ==
       std::future_status::ready) {
-    ESP_LOGI(kTag, "load finished. adding to page.");
     auto result = loading_page_->get();
     AddResults(loading_pos_.value_or(END), result);
 
@@ -125,12 +124,10 @@ auto TrackBrowser::OnItemSelected(lv_event_t* ev) -> void {
     return;
   }
   if (index < kPageBuffer) {
-    ESP_LOGI(kTag, "fetch page at start");
     FetchNewPage(START);
     return;
   }
   if (index > GetNumRecords() - kPageBuffer) {
-    ESP_LOGI(kTag, "fetch page at end");
     FetchNewPage(END);
     return;
   }
@@ -254,7 +251,6 @@ auto TrackBrowser::DropPage(Position pos) -> void {
 
 auto TrackBrowser::FetchNewPage(Position pos) -> void {
   if (loading_page_) {
-    ESP_LOGI(kTag, "already loading; giving up");
     return;
   }
 
@@ -268,7 +264,6 @@ auto TrackBrowser::FetchNewPage(Position pos) -> void {
       break;
   }
   if (!cont) {
-    ESP_LOGI(kTag, "out of pages; giving up");
     return;
   }
 
@@ -282,11 +277,9 @@ auto TrackBrowser::FetchNewPage(Position pos) -> void {
   if (current_pages_.size() >= kMaxPages) {
     switch (pos) {
       case START:
-        ESP_LOGI(kTag, "dropping end page");
         DropPage(END);
         break;
       case END:
-        ESP_LOGI(kTag, "dropping start page");
         DropPage(START);
         break;
     }

src/ui/ui_fsm.cpp

@@ -120,7 +120,7 @@ void Browse::react(const internal::RecordSelected& ev) {
     ESP_LOGI(kTag, "selected track '%s'", ev.record.text()->c_str());
     // TODO(jacqueline): We should also send some kind of playlist info here.
     sQueue->Clear();
-    sQueue->AddLast(ev.record.track()->data().id());
+    sQueue->AddLast(*ev.record.track());
     transit<Playing>();
   } else {
     ESP_LOGI(kTag, "selected record '%s'", ev.record.text()->c_str());