fix: compatible with NCM player

src/common/log.hpp

@@ -15,12 +15,14 @@
 #include "spdlog/sinks/base_sink.h"
 #include "spdlog/sinks/dist_sink.h"
 #include "spdlog/details/null_mutex.h"
-
 #include "nlohmann/json.hpp"
 
+#include "common/consts.hpp"
+
 #include <string>
 #include <memory>
 #include <mutex>
+#include <span>
 
 // https://fmt.dev/latest/api.html#udt
 template <>
@@ -55,7 +57,7 @@ struct fmt::formatter<nlohmann::json> : formatter<std::string> {
 template <>
 struct fmt::formatter<GUID> : formatter<string_view> {
  auto format(const GUID &guid, format_context &ctx) const {
- // claud-3-sonnet
+ // by claud-3-sonnet
  auto formatted = fmt::format("{:08X}-{:04X}-{:04X}-{:02X}{:02X}-{:02X}{:02X}{:02X}{:02X}{:02X}{:02X}",
  guid.Data1,
  guid.Data2,
@@ -72,6 +74,47 @@ struct fmt::formatter<GUID> : formatter<string_view> {
  }
 };
 
+// by claud-3-sonnet
+template <>
+struct fmt::formatter<fb2k_ncm::ncm_file_st> : fmt::formatter<std::string> {
+ auto format(const fb2k_ncm::ncm_file_st &file, format_context &ctx) {
+ const uint8_t stub[] = {0xde, 0xad, 0xc0, 0xdd}; // DEADC0DE
+ auto &&fmt_stub = fmt::join(std::span(stub, sizeof(stub)), "");
+ auto formatted = fmt::format(
+ "{{"
+ "magic: {:#x}, "
+ "unknown_gap_2b: [{:#x}, {:#x}], "
+ "rc4_seed_len: {}, "
+ "rc4_seed: {:X}, "
+ "meta_len: {}, "
+ "meta_content: {:X}, "
+ "unknown_gap_5b: [{:#x}, {:#x}, {:#x}, {:#x}, {:#x}], "
+ "album_image_size: [{}, {}], "
+ "album_image: {:X}... , "
+ "audio_content: {:X}..."
+ "}}",
+ file.magic,
+ file.unknown_gap_2b[0],
+ file.unknown_gap_2b[1],
+ file.rc4_seed_len,
+ (!!file.rc4_seed) ? fmt::join(std::span(file.rc4_seed, file.rc4_seed_len), "") : std::move(fmt_stub),
+ file.meta_len,
+ (!!file.meta_content) ? fmt::join(std::span(file.meta_content, file.meta_len), "") : std::move(fmt_stub),
+ file.unknown_gap_5b[0],
+ file.unknown_gap_5b[1],
+ file.unknown_gap_5b[2],
+ file.unknown_gap_5b[3],
+ file.unknown_gap_5b[4],
+ file.album_image_size[0],
+ file.album_image_size[1],
+ (!!file.album_image) ? fmt::join(std::span(file.album_image, file.album_image_size[0] <= 32 ?: 32), "") : std::move(fmt_stub),
+ (!!file.audio_content) ? fmt::join(std::span(file.audio_content, 32), "") : std::move(fmt_stub));
+ return fmt::format_to(ctx.out(), "{}", formatted);
+ }
+};
+
+// --------- SPDLOG SINKS ---------
+
 template <typename Mutex>
 class fb2k_console_sink : public spdlog::sinks::base_sink<Mutex> {
  using base_t = spdlog::sinks::base_sink<Mutex>;

src/input_ncm.cpp

@@ -36,19 +36,32 @@ inline void fb2k_ncm::input_ncm::retag(const file_info &p_info, abort_callback &
  DEBUG_LOG("input_ncm::retag()");
  // Replay Gain
  file_info_impl cur_file_info;
- decoder_->get_info(0, cur_file_info, p_abort);
+ source_info_writer_->get_info(0, cur_file_info, p_abort);
  cur_file_info.set_replaygain(p_info.get_replaygain());
  source_info_writer_->set_info(0, cur_file_info, p_abort);
  source_info_writer_->commit(p_abort);
 
  // Meta tags
- auto meta = meta_processor(p_info);
- ncm_file_->overwrite_meta(meta.dump(), p_abort);
+ // NOTE: Always do differential update, to maximally avoid appending "overwrite" key,
+ // which will change the "163 key xxxx" content.
+ auto target_json = meta_processor(p_info).dump();
+ this->get_info(cur_file_info, p_abort);
+ auto current_json = meta_processor(cur_file_info).dump();
+
+ if (current_json.contains(overwrite_key)) {
+ current_json.erase(overwrite_key);
+ }
+
+ auto diff = json_t::diff(current_json, target_json);
+ ncm_file_->overwrite_meta(json_t::object().patch(diff), p_abort);
 }
 
+/// @brief "Clear tags" => restore the meta field (163 key) to its original state
+/// @attention ReplayGain and embedded tags in the audio content are left untouched.
+/// @note ReplayGain can be wiped by retagging, since the meta diff would be empty then.
 inline void fb2k_ncm::input_ncm::remove_tags(abort_callback &p_abort) {
  DEBUG_LOG("input_ncm::remove_tags()");
- source_info_writer_->remove_tags_fallback(p_abort);
+ // source_info_writer_->remove_tags_fallback(p_abort);
  ncm_file_->overwrite_meta(nlohmann::json(), p_abort);
 }
 

src/ncm_file.cpp

@@ -327,23 +327,25 @@ void ncm_file::overwrite_meta(const nlohmann::json &meta, abort_callback &p_abor
  // passed
 
  // embed overwriting meta into the source
- json_t live_meta = json_t::parse(meta_str_); // NOTE: use unmodified raw json string.
+
+ auto meta_str_to_write = std::string("music:");
+ nlohmann::ordered_json live_meta = nlohmann::ordered_json::parse(meta_str_); // NOTE: use unmodified raw json string to keep stricted order
  if (live_meta.contains(overwrite_key)) {
  live_meta.erase(overwrite_key); // replace the old key
  }
 
- if (!meta.is_null()) {
+ if (meta.size()) {
  live_meta[overwrite_key] = meta;
  live_meta[overwrite_key].emplace(foo_input_ncm_comment_key, foo_input_ncm_comment);
  }
- auto meta_str_to_write = std::string("music:") + live_meta.dump();
+ meta_str_to_write += live_meta.dump();
 
  DEBUG_LOG_F("Overwriting meta (to {}): {}", this->path(), meta_str_to_write);
 
  // NOTE: meta json processing:
  // 1. read <meta_len>
  // 2. XOR each byte by 0x63
- // 3. format: "164 key(Don't modify):<base64>"
+ // 3. format: "163 key(Don't modify):<base64>"
  // 4. base64 decode
  // 5. AES ECB decrypt (pkcs#7 padding)
  // 6. "music:" <json>

src/ncm_file.hpp

@@ -87,9 +87,6 @@ namespace fb2k_ncm
  const char *this_path_ = nullptr;
  ncm_file_parsed_st parsed_file_{};
  file_ptr source_;
- // std::unique_ptr<std::basic_fstream<char>> source_;
- // using fschar = decltype(source_)::element_type::char_type;
-
  std::string meta_str_;
  nlohmann::json meta_json_;
  cipher::abnormal_RC4 rc4_decryptor_;

src/ui/context_menu.cpp

@@ -187,7 +187,7 @@ namespace fb2k_ncm::ui
  retagger->commit(fb2k::noAbort); // do not interrupt committing
  retagger = nullptr; // release, to let album editor reopen the file
 
- // embeded album art
+ // embedded album art
  auto album_extractor = album_art_extractor::g_open(ncm_file, ncm_file->path(), p_abort);
  auto album_writer = album_art_editor::g_open(nullptr, to_retag, p_abort);
  if (album_extractor.is_valid() && album_writer.is_valid()) {