Use batch_X_YYYYMMDD_HHMMSS.mp4 filename for exported recordings

src/video_writer.cpp

@@ -4,6 +4,7 @@
 #include <sstream>
 #include <iomanip>
 #include <ctime>
+#include <algorithm>
 #include <filesystem>
 #include <sys/wait.h>
 #include <unistd.h>
@@ -65,11 +66,15 @@ static std::string today_str() {
     return ss.str();
 }
 
-static std::string timestamp_str() {
+static std::string build_mp4_name(int batch_number, const std::string& counting_date) {
+    std::string date_part = counting_date;
+    date_part.erase(std::remove(date_part.begin(), date_part.end(), '-'), date_part.end());
     auto t = std::chrono::system_clock::to_time_t(std::chrono::system_clock::now());
-    std::ostringstream ss;
-    ss << std::put_time(std::localtime(&t), "%H%M%S");
-    return ss.str();
+    std::ostringstream name;
+    name << "batch_" << batch_number << "_"
+         << date_part << "_"
+         << std::put_time(std::localtime(&t), "%H%M%S") << ".mp4";
+    return name.str();
 }
 
 void VideoBatchWriter::note_motion() {
@@ -179,9 +184,7 @@ void VideoBatchWriter::stop_and_move(int batch_number) {
     std::string day_dir = output_dir_ + "/" + (current_date_.empty() ? today_str() : current_date_);
     ensure_dir(day_dir);
 
-    std::ostringstream name;
-    name << "batch_" << batch_number << "_" << timestamp_str() << ".mp4";
-    std::string dst = day_dir + "/" + name.str();
+    std::string dst = day_dir + "/" + build_mp4_name(batch_number, current_date_);
 
     pid_t pid = fork();
     if (pid == 0) {
@@ -208,8 +211,7 @@ void VideoBatchWriter::shutdown() {
         if (prev_state == CONFIRMED || prev_state == STOPPING) {
             std::string day_dir = output_dir_ + "/" + (current_date_.empty() ? today_str() : current_date_);
             ensure_dir(day_dir);
-            std::string dst = day_dir + "/" +
-                fs::path(src).filename().string();
+            std::string dst = day_dir + "/" + build_mp4_name(current_batch_, current_date_);
 
             pid_t pid = fork();
             if (pid == 0) {