From a6a7a1613c6a37fe5f81c4c394cffdd65d9af9be Mon Sep 17 00:00:00 2001
From: Stenzek <stenzek@gmail.com>
Date: Tue, 16 May 2023 01:00:41 +1000
Subject: [PATCH] System: Add fast_forward_to_first_frame boot parameter

---
 src/core/system.cpp | 42 +++++++++++++++++++++++++++++++++++++++---
 src/core/system.h   |  3 ++-
 2 files changed, 41 insertions(+), 4 deletions(-)

diff --git a/src/core/system.cpp b/src/core/system.cpp
index fbf528405..132a012f1 100644
--- a/src/core/system.cpp
+++ b/src/core/system.cpp
@@ -108,6 +108,7 @@ static void DoRunahead();
 static void DoMemorySaveStates();
 
 static bool Initialize(bool force_software_renderer);
+static bool FastForwardToFirstFrame();
 
 static bool UpdateGameSettingsLayer();
 static void UpdateRunningGame(const char* path, CDImage* image, bool booting);
@@ -140,6 +141,7 @@ static std::string s_running_game_serial;
 static std::string s_running_game_title;
 static System::GameHash s_running_game_hash;
 static bool s_running_unknown_game;
+static bool s_was_fast_booted;
 
 static float s_throttle_frequency = 60.0f;
 static float s_target_speed = 1.0f;
@@ -331,6 +333,11 @@ bool System::IsRunningUnknownGame()
   return s_running_unknown_game;
 }
 
+bool System::WasFastBooted()
+{
+  return s_was_fast_booted;
+}
+
 const BIOS::ImageInfo* System::GetBIOSImageInfo()
 {
   return s_bios_image_info;
@@ -520,7 +527,7 @@ bool System::GetGameDetailsFromImage(CDImage* cdi, std::string* out_id, GameHash
       pos++;
     }
   }
-  
+
   if (out_id)
   {
     if (id.empty())
@@ -635,7 +642,7 @@ std::string System::GetExecutableNameForImage(CDImage* cdi, bool strip_subdirect
 }
 
 bool System::ReadExecutableFromImage(CDImage* cdi, std::string* out_executable_name,
-  std::vector<u8>* out_executable_data)
+                                     std::vector<u8>* out_executable_data)
 {
   ISOReader iso;
   if (!iso.Open(cdi, 1))
@@ -644,7 +651,8 @@ bool System::ReadExecutableFromImage(CDImage* cdi, std::string* out_executable_n
   return ReadExecutableFromImage(iso, out_executable_name, out_executable_data);
 }
 
-bool System::ReadExecutableFromImage(ISOReader& iso, std::string* out_executable_name, std::vector<u8>* out_executable_data)
+bool System::ReadExecutableFromImage(ISOReader& iso, std::string* out_executable_name,
+                                     std::vector<u8>* out_executable_data)
 {
   const std::string executable_path = GetExecutableNameForImage(iso, false);
   Log_DevPrintf("Executable path: '%s'", executable_path.c_str());
@@ -1295,9 +1303,15 @@ bool System::BootSystem(SystemBootParameters parameters)
                                                                         g_settings.bios_patch_fast_boot))
   {
     if (s_bios_image_info && s_bios_image_info->patch_compatible)
+    {
+      // TODO: Fast boot without patches...
       BIOS::PatchBIOSFastBoot(Bus::g_bios, Bus::BIOS_SIZE);
+      s_was_fast_booted = true;
+    }
     else
+    {
       Log_ErrorPrintf("Not patching fast boot, as BIOS is not patch compatible.");
+    }
   }
 
   // Good to go.
@@ -1337,6 +1351,9 @@ bool System::BootSystem(SystemBootParameters parameters)
   if (parameters.load_image_to_ram || g_settings.cdrom_load_image_to_ram)
     CDROM::PrecacheMedia();
 
+  if (parameters.fast_forward_to_first_frame)
+    FastForwardToFirstFrame();
+
   if (g_settings.audio_dump_on_boot)
     StartDumpingAudio();
 
@@ -1519,6 +1536,7 @@ void System::DestroySystem()
 
   s_bios_hash = {};
   s_bios_image_info = nullptr;
+  s_was_fast_booted = false;
 
   Host::OnSystemDestroyed();
 }
@@ -1540,6 +1558,24 @@ void System::ClearRunningGame()
 #endif
 }
 
+bool System::FastForwardToFirstFrame()
+{
+  // If we're taking more than 60 seconds to load the game, oof..
+  static constexpr u32 MAX_FRAMES_TO_SKIP = 30 * 60;
+  const u32 current_frame_number = s_frame_number;
+  const u32 current_internal_frame_number = s_internal_frame_number;
+
+  SPU::SetAudioOutputMuted(true);
+  while (s_internal_frame_number == current_internal_frame_number &&
+         (s_frame_number - current_frame_number) <= MAX_FRAMES_TO_SKIP)
+  {
+    System::RunFrame();
+  }
+  SPU::SetAudioOutputMuted(false);
+
+  return (s_internal_frame_number != current_internal_frame_number);
+}
+
 void System::Execute()
 {
   while (IsRunning())
diff --git a/src/core/system.h b/src/core/system.h
index 3d2d8cc46..8eda2c988 100644
--- a/src/core/system.h
+++ b/src/core/system.h
@@ -45,6 +45,7 @@ struct SystemBootParameters
   u32 media_playlist_index = 0;
   bool load_image_to_ram = false;
   bool force_software_renderer = false;
+  bool fast_forward_to_first_frame = false;
 };
 
 struct SaveStateInfo
@@ -113,7 +114,6 @@ ConsoleRegion GetConsoleRegionForDiscRegion(DiscRegion region);
 std::string GetExecutableNameForImage(CDImage* cdi, bool strip_subdirectories);
 bool ReadExecutableFromImage(CDImage* cdi, std::string* out_executable_name, std::vector<u8>* out_executable_data);
 
-bool IsValidGameImage(CDImage* cdi);
 std::string GetGameHashId(GameHash hash);
 bool GetGameDetailsFromImage(CDImage* cdi, std::string* out_id, GameHash* out_hash);
 DiscRegion GetRegionForSerial(std::string_view serial);
@@ -187,6 +187,7 @@ const std::string& GetGameSerial();
 const std::string& GetGameTitle();
 GameHash GetGameHash();
 bool IsRunningUnknownGame();
+bool WasFastBooted();
 
 const BIOS::ImageInfo* GetBIOSImageInfo();
 const BIOS::Hash& GetBIOSHash();