/* All user scripts should derive from the base "Application" class */

require ("Application");

/* Get the Gamma library functions and methods for ODBC and/or
 * Windows programming.  Uncomment either or both. */

//require ("WindowsSupport");
//require ("ODBCSupport");

/* Applications share the execution thread and the global name
 * space, so we create a class that contains all of the functions
 * and variables for the application.  This does two things:
 *   1) creates a private name space for the application, and
 *   2) allows you to re-load the application to create either
 *      a new unique instance or multiple instances without
 *      damaging an existing running instance.
 */
class ExportOPCItems Application
{
	//The name of the file to write
	filename = "C:\\OPC_Items_Export\\OPCTagList.csv";
	
	//the data domain you are exporting from
	domainName = "topserver";
	
	//this is not needed unless you are also using the AddOPCItemsCSV.g script for importing
	connName = "OPCConnectionName";  
	
	//this tag is our File Pointer once the file is opened
	fp;
}

/* Use methods to create functions outside the 'main line'. */
method ExportOPCItems.writeToFile ()
{
	
	if ((.fp = open(.filename, "w", nil)) != nil);
	{
	
		local tags = datahub_points(.domainName);
		
		//this is the first line in the CSV File used for importing.  
		//We must have something because the first line is ignored when importing.
		//the line variable will hold the line we write out to the file each time.  
		local line = "OPC Connection Name in the DataHub,OPC Server Item ID,Point Name in DataHub (can be the same as ItemID), Seperator\n";  //the line we write to the file
		
		writec(.fp, line);	
		
		with tag in tags do 
		{
			if(tag.flags != 307)
			{
				local temp = datahub_command(format("(OPCQueryPoint %s \"%s\")", .connName, tag.name), 1);
				
				local splitArray = list_to_array(string_split(temp, "\"", 0));
				local serverItemId = splitArray[5];	
				princ(format(" Item is named - %a - %a \n", (serverItemId), (tag.name)));
				line = format("%a,%a,%a,%a\n", .connName, serverItemId, tag.name, ",");
				writec(.fp, line);
			}
		}
	
		princ("\n");
	}
	
	close(.fp);
}

/* Write the 'main line' of the program here. */
method ExportOPCItems.constructor ()
{
	.writeToFile();
	
	
}

/* Any code to be run when the program gets shut down. */
method ExportOPCItems.destructor ()
{
}

/* Start the program by instantiating the class.  If your
 * constructor code does not create a persistent reference to
 * the instance (self), then it will be destroyed by the
 * garbage collector soon after creation.  If you do not want
 * this to happen, assign the instance to a global variable, or
 * create a static data member in your class to which you assign
 * 'self' during the construction process.  ApplicationSingleton()
 * does this for you automatically. */
ApplicationSingleton (ExportOPCItems);