Use libcppbor for much much nicer db encoding

7 files changed, 125 insertions, 360 deletions

diff --git a/src/database/CMakeLists.txt b/src/database/CMakeLists.txt
index dffc3a26..26c14815 100644
--- a/src/database/CMakeLists.txt
+++ b/src/database/CMakeLists.txt
@@ -7,7 +7,7 @@ idf_component_register(
   "file_gatherer.cpp" "tag_parser.cpp" "index.cpp"
   INCLUDE_DIRS "include"
   REQUIRES "result" "span" "esp_psram" "fatfs" "libtags" "komihash" "cbor"
-  "tasks" "memory" "util" "tinyfsm" "events" "opusfile")
+  "tasks" "memory" "util" "tinyfsm" "events" "opusfile" "libcppbor")
 
 target_compile_options(${COMPONENT_LIB} PRIVATE ${EXTRA_WARNINGS})
 
diff --git a/src/database/database.cpp b/src/database/database.cpp
index 9d29aea8..60aa69fc 100644
--- a/src/database/database.cpp
+++ b/src/database/database.cpp
@@ -126,9 +126,9 @@ auto Database::Update() -> std::future<void> {
     ESP_LOGI(kTag, "dropping stale indexes");
     {
       std::unique_ptr<leveldb::Iterator> it{db_->NewIterator(read_options)};
-      OwningSlice prefix = EncodeAllIndexesPrefix();
-      it->Seek(prefix.slice);
-      while (it->Valid() && it->key().starts_with(prefix.slice)) {
+      std::string prefix = EncodeAllIndexesPrefix();
+      it->Seek(prefix);
+      while (it->Valid() && it->key().starts_with(prefix)) {
         db_->Delete(leveldb::WriteOptions(), it->key());
         it->Next();
       }
@@ -139,9 +139,9 @@ auto Database::Update() -> std::future<void> {
     {
       uint64_t num_processed = 0;
       std::unique_ptr<leveldb::Iterator> it{db_->NewIterator(read_options)};
-      OwningSlice prefix = EncodeDataPrefix();
-      it->Seek(prefix.slice);
-      while (it->Valid() && it->key().starts_with(prefix.slice)) {
+      std::string prefix = EncodeDataPrefix();
+      it->Seek(prefix);
+      while (it->Valid() && it->key().starts_with(prefix)) {
         num_processed++;
         events::Ui().Dispatch(event::UpdateProgress{
             .stage = event::UpdateProgress::Stage::kVerifyingExistingTracks,
@@ -215,10 +215,10 @@ auto Database::Update() -> std::future<void> {
 
       // Check for any existing record with the same hash.
       uint64_t hash = tags->Hash();
-      OwningSlice key = EncodeHashKey(hash);
+      std::string key = EncodeHashKey(hash);
       std::optional<TrackId> existing_hash;
       std::string raw_entry;
-      if (db_->Get(leveldb::ReadOptions(), key.slice, &raw_entry).ok()) {
+      if (db_->Get(leveldb::ReadOptions(), key, &raw_entry).ok()) {
         existing_hash = ParseHashValue(raw_entry);
       }
 
@@ -306,9 +306,9 @@ auto Database::GetBulkTracks(std::vector<TrackId> ids)
         std::unique_ptr<leveldb::Iterator> it{
             db_->NewIterator(leveldb::ReadOptions{})};
         for (const TrackId& id : sorted_ids) {
-          OwningSlice key = EncodeDataKey(id);
-          it->Seek(key.slice);
-          if (!it->Valid() || it->key() != key.slice) {
+          std::string key = EncodeDataKey(id);
+          it->Seek(key);
+          if (!it->Valid() || it->key() != key) {
             // This id wasn't found at all. Skip it.
             continue;
           }
@@ -354,9 +354,9 @@ auto Database::GetTracksByIndex(const IndexInfo& index, std::size_t page_size)
             .depth = 0,
             .components_hash = 0,
         };
-        OwningSlice prefix = EncodeIndexPrefix(header);
-        Continuation c{.prefix = prefix.data,
-                       .start_key = prefix.data,
+        std::string prefix = EncodeIndexPrefix(header);
+        Continuation c{.prefix = {prefix.data(), prefix.size()},
+                       .start_key = {prefix.data(), prefix.size()},
                        .forward = true,
                        .was_prev_forward = true,
                        .page_size = page_size};
@@ -366,8 +366,9 @@ auto Database::GetTracksByIndex(const IndexInfo& index, std::size_t page_size)
 
 auto Database::GetTracks(std::size_t page_size) -> std::future<Result<Track>*> {
   return worker_task_->Dispatch<Result<Track>*>([=, this]() -> Result<Track>* {
-    Continuation c{.prefix = EncodeDataPrefix().data,
-                   .start_key = EncodeDataPrefix().data,
+    std::string prefix = EncodeDataPrefix();
+    Continuation c{.prefix = {prefix.data(), prefix.size()},
+                   .start_key = {prefix.data(), prefix.size()},
                    .forward = true,
                    .was_prev_forward = true,
                    .page_size = page_size};
@@ -414,7 +415,7 @@ auto Database::dbMintNewTrackId() -> TrackId {
   }
 
   if (!db_->Put(leveldb::WriteOptions(), kTrackIdKey,
-                TrackIdToBytes(next_id + 1).slice)
+                TrackIdToBytes(next_id + 1))
            .ok()) {
     ESP_LOGE(kTag, "failed to write next track id");
   }
@@ -423,25 +424,25 @@ auto Database::dbMintNewTrackId() -> TrackId {
 }
 
 auto Database::dbEntomb(TrackId id, uint64_t hash) -> void {
-  OwningSlice key = EncodeHashKey(hash);
-  OwningSlice val = EncodeHashValue(id);
-  if (!db_->Put(leveldb::WriteOptions(), key.slice, val.slice).ok()) {
+  std::string key = EncodeHashKey(hash);
+  std::string val = EncodeHashValue(id);
+  if (!db_->Put(leveldb::WriteOptions(), key, val).ok()) {
     ESP_LOGE(kTag, "failed to entomb #%llx (id #%lx)", hash, id);
   }
 }
 
 auto Database::dbPutTrackData(const TrackData& s) -> void {
-  OwningSlice key = EncodeDataKey(s.id());
-  OwningSlice val = EncodeDataValue(s);
-  if (!db_->Put(leveldb::WriteOptions(), key.slice, val.slice).ok()) {
+  std::string key = EncodeDataKey(s.id());
+  std::string val = EncodeDataValue(s);
+  if (!db_->Put(leveldb::WriteOptions(), key, val).ok()) {
     ESP_LOGE(kTag, "failed to write data for #%lx", s.id());
   }
 }
 
 auto Database::dbGetTrackData(TrackId id) -> std::shared_ptr<TrackData> {
-  OwningSlice key = EncodeDataKey(id);
+  std::string key = EncodeDataKey(id);
   std::string raw_val;
-  if (!db_->Get(leveldb::ReadOptions(), key.slice, &raw_val).ok()) {
+  if (!db_->Get(leveldb::ReadOptions(), key, &raw_val).ok()) {
     ESP_LOGW(kTag, "no key found for #%lx", id);
     return {};
   }
@@ -449,17 +450,17 @@ auto Database::dbGetTrackData(TrackId id) -> std::shared_ptr<TrackData> {
 }
 
 auto Database::dbPutHash(const uint64_t& hash, TrackId i) -> void {
-  OwningSlice key = EncodeHashKey(hash);
-  OwningSlice val = EncodeHashValue(i);
-  if (!db_->Put(leveldb::WriteOptions(), key.slice, val.slice).ok()) {
+  std::string key = EncodeHashKey(hash);
+  std::string val = EncodeHashValue(i);
+  if (!db_->Put(leveldb::WriteOptions(), key, val).ok()) {
     ESP_LOGE(kTag, "failed to write hash for #%lx", i);
   }
 }
 
 auto Database::dbGetHash(const uint64_t& hash) -> std::optional<TrackId> {
-  OwningSlice key = EncodeHashKey(hash);
+  std::string key = EncodeHashKey(hash);
   std::string raw_val;
-  if (!db_->Get(leveldb::ReadOptions(), key.slice, &raw_val).ok()) {
+  if (!db_->Get(leveldb::ReadOptions(), key, &raw_val).ok()) {
     ESP_LOGW(kTag, "no key found for hash #%llx", hash);
     return {};
   }
@@ -672,10 +673,10 @@ auto IndexRecord::Expand(std::size_t page_size) const
     return {};
   }
   IndexKey::Header new_header = ExpandHeader(key_.header, key_.item);
-  OwningSlice new_prefix = EncodeIndexPrefix(new_header);
+  std::string new_prefix = EncodeIndexPrefix(new_header);
   return Continuation{
-      .prefix = new_prefix.data,
-      .start_key = new_prefix.data,
+      .prefix = {new_prefix.data(), new_prefix.size()},
+      .start_key = {new_prefix.data(), new_prefix.size()},
       .forward = true,
       .was_prev_forward = true,
       .page_size = page_size,
diff --git a/src/database/include/records.hpp b/src/database/include/records.hpp
index e7d7738c..e13c6568 100644
--- a/src/database/include/records.hpp
+++ b/src/database/include/records.hpp
@@ -22,32 +22,19 @@
 namespace database {
 
 /*
- * Helper class for creating leveldb Slices bundled with the data they point to.
- * Slices are otherwise non-owning, which can make handling them post-creation
- * difficult.
- */
-class OwningSlice {
- public:
-  std::pmr::string data;
-  leveldb::Slice slice;
-
-  explicit OwningSlice(std::pmr::string d);
-};
-
-/*
  * Returns the prefix added to every TrackData key. This can be used to iterate
  * over every data record in the database.
  */
-auto EncodeDataPrefix() -> OwningSlice;
+auto EncodeDataPrefix() -> std::string;
 
 /* Encodes a data key for a track with the specified id. */
-auto EncodeDataKey(const TrackId& id) -> OwningSlice;
+auto EncodeDataKey(const TrackId& id) -> std::string;
 
 /*
  * Encodes a TrackData instance into bytes, in preparation for storing it within
  * the database. This encoding is consistent, and will remain stable over time.
  */
-auto EncodeDataValue(const TrackData& track) -> OwningSlice;
+auto EncodeDataValue(const TrackData& track) -> std::string;
 
 /*
  * Parses bytes previously encoded via EncodeDataValue back into a TrackData.
@@ -56,14 +43,14 @@ auto EncodeDataValue(const TrackData& track) -> OwningSlice;
 auto ParseDataValue(const leveldb::Slice& slice) -> std::shared_ptr<TrackData>;
 
 /* Encodes a hash key for the specified hash. */
-auto EncodeHashKey(const uint64_t& hash) -> OwningSlice;
+auto EncodeHashKey(const uint64_t& hash) -> std::string;
 
 /*
  * Encodes a hash value (at this point just a track id) into bytes, in
  * preparation for storing within the database. This encoding is consistent, and
  * will remain stable over time.
  */
-auto EncodeHashValue(TrackId id) -> OwningSlice;
+auto EncodeHashValue(TrackId id) -> std::string;
 
 /*
  * Parses bytes previously encoded via EncodeHashValue back into a track id. May
@@ -72,17 +59,17 @@ auto EncodeHashValue(TrackId id) -> OwningSlice;
 auto ParseHashValue(const leveldb::Slice&) -> std::optional<TrackId>;
 
 /* Encodes a prefix that matches all index keys, of all ids and depths. */
-auto EncodeAllIndexesPrefix() -> OwningSlice;
+auto EncodeAllIndexesPrefix() -> std::string;
 
 /*
  */
-auto EncodeIndexPrefix(const IndexKey::Header&) -> OwningSlice;
+auto EncodeIndexPrefix(const IndexKey::Header&) -> std::string;
 
-auto EncodeIndexKey(const IndexKey&) -> OwningSlice;
+auto EncodeIndexKey(const IndexKey&) -> std::string;
 auto ParseIndexKey(const leveldb::Slice&) -> std::optional<IndexKey>;
 
 /* Encodes a TrackId as bytes. */
-auto TrackIdToBytes(TrackId id) -> OwningSlice;
+auto TrackIdToBytes(TrackId id) -> std::string;
 
 /*
  * Converts a track id encoded via TrackIdToBytes back into a TrackId. May
diff --git a/src/database/include/track.hpp b/src/database/include/track.hpp
index 3c7b20fa..44bfbc54 100644
--- a/src/database/include/track.hpp
+++ b/src/database/include/track.hpp
@@ -117,7 +117,6 @@ class TrackData {
   const TrackId id_;
   const std::pmr::string filepath_;
   const uint64_t tags_hash_;
-  const uint32_t play_count_;
   const bool is_tombstoned_;
 
  public:
@@ -126,18 +125,15 @@ class TrackData {
       : id_(id),
         filepath_(path, &memory::kSpiRamResource),
         tags_hash_(hash),
-        play_count_(0),
         is_tombstoned_(false) {}
 
   TrackData(TrackId id,
             const std::pmr::string& path,
             uint64_t hash,
-            uint32_t play_count,
             bool is_tombstoned)
       : id_(id),
         filepath_(path, &memory::kSpiRamResource),
         tags_hash_(hash),
-        play_count_(play_count),
         is_tombstoned_(is_tombstoned) {}
 
   TrackData(TrackData&& other) = delete;
@@ -147,7 +143,6 @@ class TrackData {
 
   auto id() const -> TrackId { return id_; }
   auto filepath() const -> std::pmr::string { return filepath_; }
-  auto play_count() const -> uint32_t { return play_count_; }
   auto tags_hash() const -> uint64_t { return tags_hash_; }
   auto is_tombstoned() const -> bool { return is_tombstoned_; }
 
diff --git a/src/database/index.cpp b/src/database/index.cpp
index 79939aaa..c7fd753a 100644
--- a/src/database/index.cpp
+++ b/src/database/index.cpp
@@ -94,7 +94,7 @@ auto Index(const IndexInfo& info, const Track& t, leveldb::WriteBatch* batch)
     }
 
     auto encoded = EncodeIndexKey(key);
-    batch->Put(encoded.slice, {value.data(), value.size()});
+    batch->Put(encoded, {value.data(), value.size()});
 
     // If there are more components after this, then we need to finish by
     // narrowing the header with the current title.
diff --git a/src/database/records.cpp b/src/database/records.cpp
index 103b3547..37ea429b 100644
--- a/src/database/records.cpp
+++ b/src/database/records.cpp
@@ -7,6 +7,7 @@
 #include "records.hpp"
 
 #include <stdint.h>
+#include <sys/_stdint.h>
 
 #include <functional>
 #include <iomanip>
@@ -15,7 +16,8 @@
 #include <string>
 #include <vector>
 
-#include "cbor.h"
+#include "cppbor.h"
+#include "cppbor_parse.h"
 #include "esp_log.h"
 
 #include "index.hpp"
@@ -49,244 +51,76 @@ static const char kHashPrefix = 'H';
 static const char kIndexPrefix = 'I';
 static const char kFieldSeparator = '\0';
 
-using ostringstream =
-    std::basic_ostringstream<char,
-                             std::char_traits<char>,
-                             std::pmr::polymorphic_allocator<char>>;
-
-/*
- * Helper function for allocating an appropriately-sized byte buffer, then
- * encoding data into it.
- *
- * 'T' should be a callable that takes a CborEncoder* as
- * an argument, and stores values within that encoder. 'T' will be called
- * exactly twice: first to detemine the buffer size, and then second to do the
- * encoding.
- *
- * 'out_buf' will be set to the location of newly allocated memory; it is up to
- * the caller to free it. Returns the size of 'out_buf'.
- */
-template <typename T>
-auto cbor_encode(uint8_t** out_buf, T fn) -> std::size_t {
-  // First pass: work out how many bytes we will encode into.
-  // FIXME: With benchmarking to help, we could consider preallocting a small
-  // buffer here to do the whole encoding in one pass.
-  CborEncoder size_encoder;
-  cbor_encoder_init(&size_encoder, NULL, 0, 0);
-  std::invoke(fn, &size_encoder);
-  std::size_t buf_size = cbor_encoder_get_extra_bytes_needed(&size_encoder);
-
-  // Second pass: do the encoding.
-  CborEncoder encoder;
-  *out_buf = new uint8_t[buf_size];
-  cbor_encoder_init(&encoder, *out_buf, buf_size, 0);
-  std::invoke(fn, &encoder);
-
-  return buf_size;
-}
-
-OwningSlice::OwningSlice(std::pmr::string d)
-    : data(d), slice(data.data(), data.size()) {}
-
 /* 'D/' */
-auto EncodeDataPrefix() -> OwningSlice {
-  char data[2] = {kDataPrefix, kFieldSeparator};
-  return OwningSlice({data, 2});
+auto EncodeDataPrefix() -> std::string {
+  return {kDataPrefix, kFieldSeparator};
 }
 
 /* 'D/ 0xACAB' */
-auto EncodeDataKey(const TrackId& id) -> OwningSlice {
-  ostringstream output;
-  output.put(kDataPrefix).put(kFieldSeparator);
-  output << TrackIdToBytes(id).data;
-  return OwningSlice(output.str());
+auto EncodeDataKey(const TrackId& id) -> std::string {
+  return EncodeDataPrefix() + TrackIdToBytes(id);
 }
 
-auto EncodeDataValue(const TrackData& track) -> OwningSlice {
-  uint8_t* buf;
-  std::size_t buf_len = cbor_encode(&buf, [&](CborEncoder* enc) {
-    CborEncoder array_encoder;
-    CborError err;
-    err = cbor_encoder_create_array(enc, &array_encoder, 5);
-    if (err != CborNoError && err != CborErrorOutOfMemory) {
-      ESP_LOGE(kTag, "encoding err %u", err);
-      return;
-    }
-    err = cbor_encode_int(&array_encoder, track.id());
-    if (err != CborNoError && err != CborErrorOutOfMemory) {
-      ESP_LOGE(kTag, "encoding err %u", err);
-      return;
-    }
-    err = cbor_encode_text_string(&array_encoder, track.filepath().c_str(),
-                                  track.filepath().size());
-    if (err != CborNoError && err != CborErrorOutOfMemory) {
-      ESP_LOGE(kTag, "encoding err %u", err);
-      return;
-    }
-    err = cbor_encode_uint(&array_encoder, track.tags_hash());
-    if (err != CborNoError && err != CborErrorOutOfMemory) {
-      ESP_LOGE(kTag, "encoding err %u", err);
-      return;
-    }
-    err = cbor_encode_int(&array_encoder, track.play_count());
-    if (err != CborNoError && err != CborErrorOutOfMemory) {
-      ESP_LOGE(kTag, "encoding err %u", err);
-      return;
-    }
-    err = cbor_encode_boolean(&array_encoder, track.is_tombstoned());
-    if (err != CborNoError && err != CborErrorOutOfMemory) {
-      ESP_LOGE(kTag, "encoding err %u", err);
-      return;
-    }
-    err = cbor_encoder_close_container(enc, &array_encoder);
-    if (err != CborNoError && err != CborErrorOutOfMemory) {
-      ESP_LOGE(kTag, "encoding err %u", err);
-      return;
-    }
-  });
-  std::pmr::string as_str(reinterpret_cast<char*>(buf), buf_len);
-  delete buf;
-  return OwningSlice(as_str);
+auto EncodeDataValue(const TrackData& track) -> std::string {
+  cppbor::Array val{
+      cppbor::Uint{track.id()},
+      cppbor::Tstr{track.filepath()},
+      cppbor::Uint{track.tags_hash()},
+      cppbor::Bool{track.is_tombstoned()},
+  };
+  return val.toString();
 }
 
 auto ParseDataValue(const leveldb::Slice& slice) -> std::shared_ptr<TrackData> {
-  CborParser parser;
-  CborValue container;
-  CborError err;
-  err = cbor_parser_init(reinterpret_cast<const uint8_t*>(slice.data()),
-                         slice.size(), 0, &parser, &container);
-  if (err != CborNoError || !cbor_value_is_container(&container)) {
-    return {};
-  }
-
-  CborValue val;
-  err = cbor_value_enter_container(&container, &val);
-  if (err != CborNoError || !cbor_value_is_unsigned_integer(&val)) {
-    return {};
-  }
-
-  uint64_t raw_int;
-  err = cbor_value_get_uint64(&val, &raw_int);
-  if (err != CborNoError) {
-    return {};
-  }
-  TrackId id = raw_int;
-  err = cbor_value_advance(&val);
-  if (err != CborNoError || !cbor_value_is_text_string(&val)) {
+  auto [item, unused, err] = cppbor::parseWithViews(
+      reinterpret_cast<const uint8_t*>(slice.data()), slice.size());
+  if (!item || item->type() != cppbor::ARRAY) {
+    return nullptr;
+  }
+  auto vals = item->asArray();
+  if (vals->size() != 4 || vals->get(0)->type() != cppbor::UINT ||
+      vals->get(1)->type() != cppbor::TSTR ||
+      vals->get(2)->type() != cppbor::UINT ||
+      vals->get(3)->type() != cppbor::SIMPLE) {
     return {};
   }
-
-  char* raw_path;
-  std::size_t len;
-  err = cbor_value_dup_text_string(&val, &raw_path, &len, &val);
-  if (err != CborNoError || !cbor_value_is_unsigned_integer(&val)) {
-    return {};
-  }
-  std::pmr::string path(raw_path, len);
-  delete raw_path;
-
-  err = cbor_value_get_uint64(&val, &raw_int);
-  if (err != CborNoError) {
-    return {};
-  }
-  uint64_t hash = raw_int;
-  err = cbor_value_advance(&val);
-  if (err != CborNoError || !cbor_value_is_unsigned_integer(&val)) {
-    return {};
-  }
-
-  err = cbor_value_get_uint64(&val, &raw_int);
-  if (err != CborNoError) {
-    return {};
-  }
-  uint32_t play_count = raw_int;
-  err = cbor_value_advance(&val);
-  if (err != CborNoError || !cbor_value_is_boolean(&val)) {
-    return {};
-  }
-
-  bool is_tombstoned;
-  err = cbor_value_get_boolean(&val, &is_tombstoned);
-  if (err != CborNoError) {
-    return {};
-  }
-
-  return std::make_shared<TrackData>(id, path, hash, play_count, is_tombstoned);
+  TrackId id = vals->get(0)->asUint()->unsignedValue();
+  auto path = vals->get(1)->asViewTstr()->view();
+  uint64_t hash = vals->get(2)->asUint()->unsignedValue();
+  bool tombstoned = vals->get(3)->asBool()->value();
+  return std::make_shared<TrackData>(
+      id, std::pmr::string{path.data(), path.size()}, hash, tombstoned);
 }
 
 /* 'H/ 0xBEEF' */
-auto EncodeHashKey(const uint64_t& hash) -> OwningSlice {
-  ostringstream output;
-  output.put(kHashPrefix).put(kFieldSeparator);
-
-  uint8_t buf[16];
-  CborEncoder enc;
-  cbor_encoder_init(&enc, buf, sizeof(buf), 0);
-  cbor_encode_uint(&enc, hash);
-  std::size_t len = cbor_encoder_get_buffer_size(&enc, buf);
-  output.write(reinterpret_cast<char*>(buf), len);
-
-  return OwningSlice(output.str());
+auto EncodeHashKey(const uint64_t& hash) -> std::string {
+  return std::string{kHashPrefix, kFieldSeparator} +
+         cppbor::Uint{hash}.toString();
 }
 
 auto ParseHashValue(const leveldb::Slice& slice) -> std::optional<TrackId> {
   return BytesToTrackId({slice.data(), slice.size()});
 }
 
-auto EncodeHashValue(TrackId id) -> OwningSlice {
+auto EncodeHashValue(TrackId id) -> std::string {
   return TrackIdToBytes(id);
 }
 
 /* 'I/' */
-auto EncodeAllIndexesPrefix() -> OwningSlice {
-  char data[2] = {kIndexPrefix, kFieldSeparator};
-  return OwningSlice({data, 2});
-}
-
-auto AppendIndexHeader(const IndexKey::Header& header, ostringstream* out)
-    -> void {
-  *out << kIndexPrefix << kFieldSeparator;
-
-  // Construct the header.
-  uint8_t* buf;
-  std::size_t buf_len = cbor_encode(&buf, [&](CborEncoder* enc) {
-    CborEncoder array_encoder;
-    CborError err;
-    err = cbor_encoder_create_array(enc, &array_encoder, 3);
-    if (err != CborNoError && err != CborErrorOutOfMemory) {
-      ESP_LOGE(kTag, "encoding err %u", err);
-      return;
-    }
-    err = cbor_encode_uint(&array_encoder, header.id);
-    if (err != CborNoError && err != CborErrorOutOfMemory) {
-      ESP_LOGE(kTag, "encoding err %u", err);
-      return;
-    }
-    err = cbor_encode_uint(&array_encoder, header.depth);
-    if (err != CborNoError && err != CborErrorOutOfMemory) {
-      ESP_LOGE(kTag, "encoding err %u", err);
-      return;
-    }
-    err = cbor_encode_uint(&array_encoder, header.components_hash);
-    if (err != CborNoError && err != CborErrorOutOfMemory) {
-      ESP_LOGE(kTag, "encoding err %u", err);
-      return;
-    }
-    err = cbor_encoder_close_container(enc, &array_encoder);
-    if (err != CborNoError && err != CborErrorOutOfMemory) {
-      ESP_LOGE(kTag, "encoding err %u", err);
-      return;
-    }
-  });
-  std::pmr::string encoded{reinterpret_cast<char*>(buf), buf_len};
-  delete buf;
-  *out << encoded << kFieldSeparator;
+auto EncodeAllIndexesPrefix() -> std::string {
+  return {kIndexPrefix, kFieldSeparator};
 }
 
-auto EncodeIndexPrefix(const IndexKey::Header& header) -> OwningSlice {
-  ostringstream out;
-  AppendIndexHeader(header, &out);
-  return OwningSlice(out.str());
+auto EncodeIndexPrefix(const IndexKey::Header& header) -> std::string {
+  std::ostringstream out;
+  out.put(kIndexPrefix).put(kFieldSeparator);
+  cppbor::Array val{
+      cppbor::Uint{header.id},
+      cppbor::Uint{header.depth},
+      cppbor::Uint{header.components_hash},
+  };
+  out << val.toString() << kFieldSeparator;
+  return out.str();
 }
 
 /*
@@ -303,93 +137,51 @@ auto EncodeIndexPrefix(const IndexKey::Header& header) -> OwningSlice {
  *  components. We store disambiguation information in the trailer; just a track
  *  id for now, but could reasonably be something like 'release year' as well.
  */
-auto EncodeIndexKey(const IndexKey& key) -> OwningSlice {
-  ostringstream out;
+auto EncodeIndexKey(const IndexKey& key) -> std::string {
+  std::ostringstream out{};
 
-  // Construct the header.
-  AppendIndexHeader(key.header, &out);
+  out << EncodeIndexPrefix(key.header);
 
   // The component should already be UTF-8 encoded, so just write it.
   if (key.item) {
-    out << *key.item;
+    out << *key.item << kFieldSeparator;
   }
 
-  // Construct the footer.
-  out << kFieldSeparator;
   if (key.track) {
-    auto encoded = TrackIdToBytes(*key.track);
-    out << encoded.data;
+    out << TrackIdToBytes(*key.track);
   }
-  return OwningSlice(out.str());
+
+  return out.str();
 }
 
 auto ParseIndexKey(const leveldb::Slice& slice) -> std::optional<IndexKey> {
   IndexKey result{};
 
   auto prefix = EncodeAllIndexesPrefix();
-  if (!slice.starts_with(prefix.slice)) {
+  if (!slice.starts_with(prefix)) {
     return {};
   }
 
-  std::string key_data = slice.ToString().substr(prefix.data.size());
-  std::size_t header_length = 0;
-  {
-    CborParser parser;
-    CborValue container;
-    CborError err;
-    err = cbor_parser_init(reinterpret_cast<const uint8_t*>(key_data.data()),
-                           key_data.size(), 0, &parser, &container);
-    if (err != CborNoError || !cbor_value_is_container(&container)) {
-      return {};
-    }
-
-    CborValue val;
-    err = cbor_value_enter_container(&container, &val);
-    if (err != CborNoError || !cbor_value_is_unsigned_integer(&val)) {
-      return {};
-    }
-
-    uint64_t raw_int;
-    err = cbor_value_get_uint64(&val, &raw_int);
-    if (err != CborNoError) {
-      return {};
-    }
-    result.header.id = raw_int;
-    err = cbor_value_advance(&val);
-    if (err != CborNoError || !cbor_value_is_unsigned_integer(&val)) {
-      return {};
-    }
-
-    err = cbor_value_get_uint64(&val, &raw_int);
-    if (err != CborNoError) {
-      return {};
-    }
-    result.header.depth = raw_int;
-    err = cbor_value_advance(&val);
-    if (err != CborNoError || !cbor_value_is_unsigned_integer(&val)) {
-      return {};
-    }
-
-    err = cbor_value_get_uint64(&val, &raw_int);
-    if (err != CborNoError) {
-      return {};
-    }
-    result.header.components_hash = raw_int;
-    err = cbor_value_advance(&val);
-    if (err != CborNoError || !cbor_value_at_end(&val)) {
-      return {};
-    }
-
-    const uint8_t* next_byte = cbor_value_get_next_byte(&val);
-    header_length =
-        next_byte - reinterpret_cast<const uint8_t*>(key_data.data());
+  std::string key_data = slice.ToString().substr(prefix.size());
+  auto [key, end_of_key, err] = cppbor::parseWithViews(
+      reinterpret_cast<const uint8_t*>(key_data.data()), key_data.size());
+  if (!key || key->type() != cppbor::ARRAY) {
+    return {};
   }
-
-  if (header_length == 0) {
+  auto as_array = key->asArray();
+  if (as_array->size() != 3 || as_array->get(0)->type() != cppbor::UINT ||
+      as_array->get(1)->type() != cppbor::UINT ||
+      as_array->get(2)->type() != cppbor::UINT) {
     return {};
   }
+  result.header.id = as_array->get(0)->asUint()->unsignedValue();
+  result.header.depth = as_array->get(1)->asUint()->unsignedValue();
+  result.header.components_hash = as_array->get(2)->asUint()->unsignedValue();
+
+  size_t header_length =
+      reinterpret_cast<const char*>(end_of_key) - key_data.data();
 
-  if (header_length >= key_data.size()) {
+  if (header_length == 0 || header_length >= key_data.size()) {
     return {};
   }
 
@@ -411,27 +203,17 @@ auto ParseIndexKey(const leveldb::Slice& slice) -> std::optional<IndexKey> {
   return result;
 }
 
-auto TrackIdToBytes(TrackId id) -> OwningSlice {
-  uint8_t buf[8];
-  CborEncoder enc;
-  cbor_encoder_init(&enc, buf, sizeof(buf), 0);
-  cbor_encode_uint(&enc, id);
-  std::size_t len = cbor_encoder_get_buffer_size(&enc, buf);
-  std::pmr::string as_str(reinterpret_cast<char*>(buf), len);
-  return OwningSlice(as_str);
+auto TrackIdToBytes(TrackId id) -> std::string {
+  return cppbor::Uint{id}.toString();
 }
 
 auto BytesToTrackId(cpp::span<const char> bytes) -> std::optional<TrackId> {
-  CborParser parser;
-  CborValue val;
-  cbor_parser_init(reinterpret_cast<const uint8_t*>(bytes.data()), bytes.size(),
-                   0, &parser, &val);
-  if (!cbor_value_is_unsigned_integer(&val)) {
+  auto [res, unused, err] = cppbor::parse(
+      reinterpret_cast<const uint8_t*>(bytes.data()), bytes.size());
+  if (!res || res->type() != cppbor::UINT) {
     return {};
   }
-  uint64_t raw_id;
-  cbor_value_get_uint64(&val, &raw_id);
-  return raw_id;
+  return res->asUint()->unsignedValue();
 }
 
 }  // namespace database
diff --git a/src/database/track.cpp b/src/database/track.cpp
index f48bb8ed..ca180124 100644
--- a/src/database/track.cpp
+++ b/src/database/track.cpp
@@ -53,15 +53,15 @@ auto TrackTags::Hash() const -> uint64_t {
 }
 
 auto TrackData::UpdateHash(uint64_t new_hash) const -> TrackData {
-  return TrackData(id_, filepath_, new_hash, play_count_, is_tombstoned_);
+  return TrackData(id_, filepath_, new_hash, is_tombstoned_);
 }
 
 auto TrackData::Entomb() const -> TrackData {
-  return TrackData(id_, filepath_, tags_hash_, play_count_, true);
+  return TrackData(id_, filepath_, tags_hash_, true);
 }
 
 auto TrackData::Exhume(const std::pmr::string& new_path) const -> TrackData {
-  return TrackData(id_, new_path, tags_hash_, play_count_, false);
+  return TrackData(id_, new_path, tags_hash_, false);
 }
 
 auto Track::TitleOrFilename() const -> std::pmr::string {