[Playback] Process paths in slippi combo files relative to the config itself

Source/Core/Common/FileUtil.cpp

@@ -28,6 +28,7 @@
 #include <shellapi.h>
 #include <windows.h>
 #include <winerror.h>
+#include <Shlwapi.h>
 #else
 #include <dirent.h>
 #include <errno.h>
@@ -723,6 +724,58 @@ std::string GetBundleDirectory()
 }
 #endif
 
+std::string GetAbsolutePathFromRelativePath(const std::string &path, const std::string &origin) {
+	std::string tempPath = path;
+	std::string tempOrigin = origin;
+#ifdef _WIN32
+	LPCWSTR winPath = s2ws(tempPath).c_str();
+	if (!PathIsRelativeW(winPath))
+	{
+		return tempPath;
+	}
+	std::replace(tempOrigin.begin(), tempOrigin.end(), '/', '\\');
+	std::replace(tempPath.begin(), tempPath.end(), '/', '\\');
+	if (tempOrigin.back() != '\\' && tempPath.front() != '\\')
+	{
+		tempOrigin.push_back('\\');
+	}
+	else if (tempOrigin.back() == '\\' && tempPath.front() == '\\')
+	{
+		tempOrigin.pop_back();
+	}
+#else
+	if (tempPath.at(0) == '/')
+	{
+		return tempPath;
+	}
+	if (tempPath.back() != '/' && tempOrigin.front() != '/')
+	{
+		tempPath.push_back('/');
+	}
+	else if (tempPath.back() == '/' && tempOrigin.front() == '/')
+	{
+		tempPath.pop_back();
+	}
+#endif
+	return tempOrigin + tempPath;
+}
+
+std::wstring s2ws(const std::string &s)
+{
+#ifdef _WIN32
+	int len;
+	int slength = (int)s.length() + 1;
+	len = MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, 0, 0);
+	wchar_t *buf = new wchar_t[len];
+	MultiByteToWideChar(CP_ACP, 0, s.c_str(), slength, buf, len);
+	std::wstring r(buf);
+	delete[] buf;
+	return r;
+#else
+	return NULL;
+#endif
+}
+
 std::string &GetExeDirectory()
 {
 	static std::string DolphinPath;

Source/Core/Common/FileUtil.h

@@ -139,6 +139,12 @@ std::string CreateTempDir();
 // Get a filename that can hopefully be atomically renamed to the given path.
 std::string GetTempFilenameForAtomicWrite(const std::string& path);
 
+// Converts a relative path to an absolute path if it is a relative one
+std::string GetAbsolutePathFromRelativePath(const std::string &path, const std::string &origin);
+
+// Converts String to WString
+std::wstring s2ws(const std::string &s);
+
 // Gets a set user directory path
 // Don't call prior to setting the base user directory
 const std::string& GetUserPath(unsigned int dir_index);

Source/Core/Core/Slippi/SlippiReplayComm.cpp

@@ -211,7 +211,7 @@ void SlippiReplayComm::loadFile()
 			{
 				json el = *it;
 				WatchSettings w = {};
-				w.path = el.value("path", "");
+				w.path = File::GetAbsolutePathFromRelativePath(el.value("path", ""), configFilePath.substr(0, configFilePath.find_last_of("\\/")));
 				w.startFrame = el.value("startFrame", Slippi::GAME_FIRST_FRAME);
 				w.endFrame = el.value("endFrame", INT_MAX);
 				w.gameStartAt = el.value("gameStartAt", "");