Add get_first_non_empty and use it into Database to simplify a little bit

src/database/database.cpp

@@ -4,8 +4,8 @@
 #include <database/database.hpp>
 #include <logger/logger.hpp>
 #include <irc/iid.hpp>
-#include <string>
 #include <uuid.h>
+#include <utils/get_first_non_empty.hpp>
 
 using namespace std::string_literals;
 
@@ -73,10 +73,11 @@ db::IrcChannelOptions Database::get_irc_channel_options_with_server_default(cons
 {
   auto coptions = Database::get_irc_channel_options(owner, server, channel);
   auto soptions = Database::get_irc_server_options(owner, server);
-  if (coptions.encodingIn.value().empty())
-    coptions.encodingIn = soptions.encodingIn;
-  if (coptions.encodingOut.value().empty())
-    coptions.encodingOut = soptions.encodingOut;
+
+  coptions.encodingIn = get_first_non_empty(coptions.encodingIn.value(),
+                                            soptions.encodingIn.value());
+  coptions.encodingOut = get_first_non_empty(coptions.encodingOut.value(),
+                                             soptions.encodingOut.value());
 
   return coptions;
 }

src/utils/get_first_non_empty.cpp

@@ -0,0 +1,11 @@
+#include <utils/get_first_non_empty.hpp>
+
+bool is_empty(const std::string& val)
+{
+  return val.empty();
+}
+
+bool is_empty(const int& val)
+{
+  return val == 0;
+}

src/utils/get_first_non_empty.hpp

@@ -0,0 +1,20 @@
+#pragma once
+
+#include <string>
+
+bool is_empty(const std::string& val);
+bool is_empty(const int& val);
+
+template <typename T>
+T get_first_non_empty(T&& last)
+{
+  return last;
+}
+
+template <typename T, typename... Args>
+T get_first_non_empty(T&& first, Args&&... args)
+{
+  if (!is_empty(first))
+    return first;
+  return get_first_non_empty(std::forward<Args>(args)...);
+}