From 01db131adb2ec7e07bed7d5db7db551d8e0b64b2 Mon Sep 17 00:00:00 2001
From: scawful <justin.scofield@outlook.com>
Date: Tue, 21 Jan 2025 22:13:00 -0500
Subject: [PATCH] Add flag handling for ROM file in main application

---
 src/app/main.cc | 14 +++++++++-----
 src/util/flag.h | 17 +++++++++++++----
 2 files changed, 22 insertions(+), 9 deletions(-)

diff --git a/src/app/main.cc b/src/app/main.cc
index b5980ff7..68a593ab 100644
--- a/src/app/main.cc
+++ b/src/app/main.cc
@@ -5,6 +5,7 @@
 #include "absl/debugging/failure_signal_handler.h"
 #include "absl/debugging/symbolize.h"
 #include "app/core/controller.h"
+#include "util/flag.h"
 
 /**
  * @namespace yaze
@@ -12,19 +13,22 @@
  */
 using namespace yaze;
 
+DECLARE_FLAG(std::string, rom_file);
+DEFINE_FLAG(std::string, rom_file, "", "The ROM file to load.");
+
 int main(int argc, char** argv) {
   absl::InitializeSymbolizer(argv[0]);
-
   absl::FailureSignalHandlerOptions options;
   options.symbolize_stacktrace = true;
   options.use_alternate_stack = true;
   options.alarm_on_failure_secs = true;
   options.call_previous_handler = true;
   absl::InstallFailureSignalHandler(options);
-
-  std::string rom_filename;
-  if (argc > 1) {
-    rom_filename = argv[1];
+  yaze::util::FlagParser parser(yaze::util::global_flag_registry());
+  RETURN_IF_EXCEPTION(parser.Parse(argc, argv));
+  std::string rom_filename = "";
+  if (!FLAGS_rom_file.empty()) {
+    rom_filename = FLAGS_rom_file;
   }
 
 #ifdef __APPLE__
diff --git a/src/util/flag.h b/src/util/flag.h
index db1bec6d..a3977fa3 100644
--- a/src/util/flag.h
+++ b/src/util/flag.h
@@ -96,7 +96,6 @@ class FlagRegistry {
   std::unordered_map<std::string, std::unique_ptr<IFlag>> flags_;
 };
 
-
 inline FlagRegistry* global_flag_registry() {
   // Guaranteed to be initialized once per process.
   static FlagRegistry* registry = new FlagRegistry();
@@ -106,9 +105,10 @@ inline FlagRegistry* global_flag_registry() {
 #define DECLARE_FLAG(type, name) extern yaze::util::Flag<type>* FLAGS_##name
 
 // Defines a global Flag<type>* FLAGS_<name> and registers it.
-#define DEFINE_FLAG(type, name, default_val, help_text)                  \
-  yaze::util::Flag<type>* FLAGS_##name =  \
-  yaze::util::global_flag_registry()->RegisterFlag<type>("--" #name, (default_val), (help_text))
+#define DEFINE_FLAG(type, name, default_val, help_text)       \
+  yaze::util::Flag<type>* FLAGS_##name =                      \
+      yaze::util::global_flag_registry()->RegisterFlag<type>( \
+          "--" #name, (default_val), (help_text))
 
 // Retrieves the current value of a declared flag.
 #define FLAG_VALUE(name) (FLAGS_##name->Get())
@@ -117,6 +117,15 @@ class FlagParser {
  public:
   explicit FlagParser(FlagRegistry* registry) : registry_(registry) {}
 
+  // Parses flags out of the given command line arguments.
+  void Parse(int argc, char** argv) {
+    std::vector<std::string> tokens;
+    for (int i = 0; i < argc; i++) {
+      tokens.push_back(argv[i]);
+    }
+    Parse(&tokens);
+  }
+
   // Parses flags out of the given token list. Recognizes forms:
   // --flag=value or --flag value
   // Any token not recognized as a flag is left in `leftover`.