UI: Update configs for new FFmpeg output changes

If a user was using FFmpeg output before pathc 0.12.0, they had to type
in the full file name to the FFmpeg output URL/Path box, which isn't
exactly compatible with the new settings.

This changes each profile's config file so that the FFmpeg output
detects whether files are used, and then extracts the file's directory
and extension and sets them accordingly to make it compatible with the
new FFmpeg file output handling.

obs/obs-app.cpp

@@ -1211,6 +1211,83 @@ static void move_to_xdg(void)
 }
 #endif
 
+static void update_ffmpeg_output(const char *path)
+{
+	ConfigFile config;
+
+	if (config.Open(path, CONFIG_OPEN_EXISTING) != CONFIG_SUCCESS)
+		return;
+
+	if (config_has_user_value(config, "AdvOut", "FFOutputToFile"))
+		return;
+
+	const char *url = config_get_string(config, "AdvOut", "FFURL");
+	if (!url)
+		return;
+
+	bool isActualURL = strstr(url, "://") != nullptr;
+	if (isActualURL)
+		return;
+
+	string urlStr = url;
+	string extension;
+
+	for (size_t i = urlStr.length(); i > 0; i--) {
+		size_t idx = i - 1;
+
+		if (urlStr[idx] == '.') {
+			extension = &urlStr[i];
+		}
+
+		if (urlStr[idx] == '\\' || urlStr[idx] == '/') {
+			urlStr[idx] = 0;
+			break;
+		}
+	}
+
+	if (urlStr.empty() || extension.empty())
+		return;
+
+	config_remove_value(config, "AdvOut", "FFURL");
+	config_set_string(config, "AdvOut", "FFFilePath", urlStr.c_str());
+	config_set_string(config, "AdvOut", "FFExtension", extension.c_str());
+	config_set_bool(config, "AdvOut", "FFOutputToFile", true);
+	config_save(config);
+}
+
+static void update_ffmpeg_outputs(void)
+{
+	char path[512];
+	int pathlen = GetConfigPath(path, 512, "obs-studio/basic/profiles");
+
+	if (pathlen <= 0)
+		return;
+	if (!os_file_exists(path))
+		return;
+
+	os_dir_t *dir = os_opendir(path);
+	if (!dir)
+		return;
+
+	struct os_dirent *ent = os_readdir(dir);
+
+	while (ent) {
+		if (ent->directory) {
+			strcat(path, "/");
+			strcat(path, ent->d_name);
+			strcat(path, "/basic.ini");
+
+			update_ffmpeg_output(path);
+
+			path[pathlen] = 0;
+		}
+
+		ent = os_readdir(dir);
+	}
+
+	os_closedir(dir);
+}
+
 int main(int argc, char *argv[])
 {
 #ifndef _WIN32
@@ -1244,6 +1321,8 @@ int main(int argc, char *argv[])
 	}
 #endif
 
+	update_ffmpeg_outputs();
+
 	fstream logFile;
 
 	curl_global_init(CURL_GLOBAL_ALL);