From 67bce173824e2ee99d858aa97145c6e1b3e81ff1 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Martin=20Kr=C3=B6ning?= <mkroening@posteo.net>
Date: Sat, 13 Jun 2020 13:46:02 +0200
Subject: [PATCH] Extract logic to NoteDataUtil::StringInterpretsAs

---
 src/NoteDataUtil.cpp  | 11 +++++++++++
 src/NoteDataUtil.h    |  5 +++++
 src/NotesLoaderSM.cpp | 46 +++++++------------------------------------
 3 files changed, 23 insertions(+), 39 deletions(-)

diff --git a/src/NoteDataUtil.cpp b/src/NoteDataUtil.cpp
index 330b3f0b58..ee5e321258 100644
--- a/src/NoteDataUtil.cpp
+++ b/src/NoteDataUtil.cpp
@@ -11,6 +11,17 @@
 #include "TimingData.h"
 #include <utility>
 
+bool NoteDataUtil::StringInterpretsAs( const std::string& str, int integer ) {
+	try
+	{
+		return std::stoi( str ) == integer;
+	}
+	catch ( const std::invalid_argument & )
+	{
+		return false;
+	}
+}
+
 // TODO: Remove these constants that aren't time signature-aware
 static const int BEATS_PER_MEASURE = 4;
 static const int ROWS_PER_MEASURE = ROWS_PER_BEAT * BEATS_PER_MEASURE;
diff --git a/src/NoteDataUtil.h b/src/NoteDataUtil.h
index a855ddd2a6..8b9ea53432 100644
--- a/src/NoteDataUtil.h
+++ b/src/NoteDataUtil.h
@@ -23,6 +23,11 @@ void LightTransformHelper( const NoteData &in, NoteData &out, const vector<int>
  * and makes it much easier to change NoteData internally in the future. */
 namespace NoteDataUtil
 {
+	/**
+	 * @brief Whether a string can be interpreted as the provided signed integer
+	 */
+	bool StringInterpretsAs( const std::string& str, int integer );
+
 	NoteType GetSmallestNoteTypeForMeasure( const NoteData &nd, int iMeasureIndex );
 	NoteType GetSmallestNoteTypeInRange( const NoteData &nd, int iStartIndex, int iEndIndex );
 	void LoadFromSMNoteDataString( NoteData &out, const RString &sSMNoteData, bool bComposite );
diff --git a/src/NotesLoaderSM.cpp b/src/NotesLoaderSM.cpp
index fa2a6c0279..b0b52148a2 100644
--- a/src/NotesLoaderSM.cpp
+++ b/src/NotesLoaderSM.cpp
@@ -3,6 +3,7 @@
 #include "BackgroundUtil.h"
 #include "GameManager.h"
 #include "MsdFile.h"
+#include "NoteDataUtil.h"
 #include "NoteTypes.h"
 #include "RageFileManager.h"
 #include "RageLog.h"
@@ -974,58 +975,25 @@ bool SMLoader::LoadFromBGChangesVector( BackgroundChange &change, std::vector<RS
 	case 6:
 		// param 7 overrides this.
 		// Backward compatibility:
-		if( change.m_def.m_sEffect.empty() )
+		if( change.m_def.m_sEffect.empty() && !NoteDataUtil::StringInterpretsAs( aBGChangeValues[5], 0 ) )
 		{
-			try
-			{
-				if( std::stoi( aBGChangeValues[5] ) != 0 )
-				{
-					change.m_def.m_sEffect = SBE_StretchNoLoop;
-				}
-			}
-			catch ( const std::invalid_argument & )
-			{
-				// Failed conversions mean it's not 0 as well
-				change.m_def.m_sEffect = SBE_StretchNoLoop;
-			}
+			change.m_def.m_sEffect = SBE_StretchNoLoop;
 		}
 		// fall through
 	case 5:
 		// param 7 overrides this.
 		// Backward compatibility:
-		if( change.m_def.m_sEffect.empty() )
+		if( change.m_def.m_sEffect.empty() && !NoteDataUtil::StringInterpretsAs( aBGChangeValues[4], 0 ) )
 		{
-			try
-			{
-				if( std::stoi( aBGChangeValues[4] ) != 0 )
-				{
-					change.m_def.m_sEffect = SBE_StretchRewind;
-				}
-			}
-			catch ( const std::invalid_argument & )
-			{
-				// Failed conversions mean it's not 0 as well
-				change.m_def.m_sEffect = SBE_StretchRewind;
-			}
+			change.m_def.m_sEffect = SBE_StretchRewind;
 		}
 		// fall through
 	case 4:
 		// param 9 overrides this.
 		// Backward compatibility:
-		if( change.m_sTransition.empty() )
+		if( change.m_sTransition.empty() && !NoteDataUtil::StringInterpretsAs( aBGChangeValues[3], 0 ) )
 		{
-			try
-			{
-				if( std::stoi( aBGChangeValues[3] ) != 0 )
-				{
-					change.m_sTransition = SBT_CrossFade;
-				}
-			}
-			catch ( const std::invalid_argument & )
-			{
-				// Failed conversions mean it's not 0 as well
-				change.m_sTransition = SBT_CrossFade;
-			}
+			change.m_sTransition = SBT_CrossFade;
 		}
 		// fall through
 	case 3: