3 files changed, 37 insertions, 2 deletions

diff --git a/src/database/database.cpp b/src/database/database.cpp
index 6106693c..70bbb78a 100644
--- a/src/database/database.cpp
+++ b/src/database/database.cpp
@@ -35,6 +35,7 @@
 #include "memory_resource.hpp"
 #include "records.hpp"
 #include "result.hpp"
+#include "spi.hpp"
 #include "tag_parser.hpp"
 #include "tasks.hpp"
 #include "track.hpp"
@@ -176,6 +177,8 @@ auto Database::Update() -> std::future<void> {
       }
     }
 
+    std::pair<uint16_t, uint16_t> newest_track{0, 0};
+
     // Stage 1: verify all existing tracks are still valid.
     ESP_LOGI(kTag, "verifying existing tracks");
     {
@@ -205,6 +208,21 @@ auto Database::Update() -> std::future<void> {
           continue;
         }
 
+        FRESULT res;
+        FILINFO info;
+        {
+          auto lock = drivers::acquire_spi();
+          res = f_stat(track->filepath().c_str(), &info);
+        }
+
+        std::pair<uint16_t, uint16_t> modified_at{0, 0};
+        if (res == FR_OK) {
+          modified_at = {info.fdate, info.ftime};
+        }
+        if (modified_at == track->modified_at()) {
+          newest_track = std::max(modified_at, newest_track);
+        }
+
         std::shared_ptr<TrackTags> tags =
             tag_parser_.ReadAndParseTags(track->filepath());
         if (!tags || tags->encoding() == Container::kUnsupported) {
@@ -212,7 +230,7 @@ auto Database::Update() -> std::future<void> {
           // malformed, or perhaps the file is missing. Either way, tombstone
           // this record.
           ESP_LOGW(kTag, "entombing missing #%lx", track->id());
-          dbPutTrackData(track->Entomb());
+          dbPutTrackData(track->Entomb().UpdateModifiedAt(modified_at));
           it->Next();
           continue;
         }
@@ -227,7 +245,8 @@ auto Database::Update() -> std::future<void> {
           // database.
           ESP_LOGI(kTag, "updating hash (%llx -> %llx)", track->tags_hash(),
                    new_hash);
-          dbPutTrackData(track->UpdateHash(new_hash));
+          dbPutTrackData(
+              track->UpdateHash(new_hash).UpdateModifiedAt(modified_at));
           dbPutHash(new_hash, track->id());
         }
 
@@ -239,6 +258,9 @@ auto Database::Update() -> std::future<void> {
       }
     }
 
+    ESP_LOGI(kTag, "newest unmodified was at %u,%u", newest_track.first,
+             newest_track.second);
+
     // Stage 2: search for newly added files.
     ESP_LOGI(kTag, "scanning for new tracks");
     uint64_t num_processed = 0;
@@ -251,6 +273,10 @@ auto Database::Update() -> std::future<void> {
       });
 
       std::pair<uint16_t, uint16_t> modified{info.fdate, info.ftime};
+      if (modified < newest_track) {
+        ESP_LOGI(kTag, "skipping old file");
+        return;
+      }
 
       std::shared_ptr<TrackTags> tags = tag_parser_.ReadAndParseTags(path);
       if (!tags || tags->encoding() == Container::kUnsupported) {
diff --git a/src/database/include/track.hpp b/src/database/include/track.hpp
index 1067b25e..af5f53df 100644
--- a/src/database/include/track.hpp
+++ b/src/database/include/track.hpp
@@ -170,6 +170,9 @@ class TrackData {
    * new location.
    */
   auto Exhume(const std::pmr::string& new_path) const -> TrackData;
+
+  auto UpdateModifiedAt(const std::pair<uint16_t, uint16_t>&) const
+      -> TrackData;
 };
 
 /*
diff --git a/src/database/track.cpp b/src/database/track.cpp
index 551379c6..6fc891a4 100644
--- a/src/database/track.cpp
+++ b/src/database/track.cpp
@@ -7,6 +7,7 @@
 #include "track.hpp"
 
 #include <komihash.h>
+#include <sys/_stdint.h>
 
 #include "memory_resource.hpp"
 
@@ -64,6 +65,11 @@ auto TrackData::Exhume(const std::pmr::string& new_path) const -> TrackData {
   return TrackData(id_, new_path, tags_hash_, false, modified_at_);
 }
 
+auto TrackData::UpdateModifiedAt(
+    const std::pair<uint16_t, uint16_t>& new_time) const -> TrackData {
+  return TrackData(id_, filepath_, tags_hash_, false, new_time);
+}
+
 auto Track::TitleOrFilename() const -> std::pmr::string {
   auto title = tags().at(Tag::kTitle);
   if (title) {