WIP add super basic gps handler

commons.hpp

@@ -99,6 +99,18 @@ struct buffer {
     return true;
   }
 
+  template<typename Func_t>
+  bool execute(const Func_t& executor)
+  {
+    const auto lk = commons::lock<commons::mutex>::get(m);
+    if(!lk)
+    {
+      return false;
+    }
+
+    executor(buf);
+  }
+
   bool print() const
   {
     const auto lk = commons::lock<commons::mutex>::get(m);
@@ -120,3 +132,62 @@ private:
   mutable commons::mutex m;
 };
 
+class gps_data
+{
+public:
+  void extract_gps_data(auto& buf)
+  {
+    buf.execute([this](auto& value) { this->copy_to_own_buf(value); });
+  }
+
+  void copy_to_own_buf(std::span<uint8_t> other)
+  {
+    auto view = std::string_view{reinterpret_cast<const char*>(other.data()), other.size()};
+
+    const auto it_begin = view.find("$GPGGA");
+
+    if(it_begin == view.npos)
+    {
+      return;
+    }
+
+    view.remove_prefix(it_begin);
+    const auto it_end = view.find("\r\n", it_begin);
+
+    if(it_end == view.npos)
+    {
+      return;
+    }
+
+    view.remove_suffix(view.size() - it_end);
+
+    if(view.size() > max_size)
+    {
+      return;
+    }
+
+    std::copy(view.begin(), view.end(), current_line.begin());
+    current_size = std::distance(view.begin(), view.end());
+    valid = true;
+  }
+
+  bool is_valid() const
+  {
+    return valid;
+  }
+
+  void print() const
+  {
+    log::info("Current GPS Data:");
+    uart_interface::write(
+        {reinterpret_cast<const char *>(current_line.data()), current_size});
+    log::linebreak();
+  }
+
+private:
+  static constexpr uint8_t max_size = 82; //defined by GPS NMEA 0183 protocol
+  size_t current_size = 0;
+  std::array<uint8_t, max_size> current_line;
+  bool valid = false;
+};
+