rLoadDataset function

Implementation

Future<void> rLoadDataset(BuildContext context, WidgetRef ref) async {
  // On loading a dataset we run the main R script to initialise a new session.

  // Get the path to the dataset from the provider to identify either a filename
  // or an R package dataset.

  String path = ref.read(pathProvider);
  String dataset = ref.read(datasetProvider);
  String package = ref.read(packageProvider);

  // TODO 20231018 gjw IF A DATASET HAS ALREADY BEEN LOADED AND NOT YET
  // PROCESSED (dataset_template.R) THEN PROCESS ELSE ASK IF WE CAN OVERWRITE IT
  // AND IF SO DO SO OTHERWISE DO NOTHING.

  debugText('R LOAD', path);

  // Ensure there is no extraneous white space.

  path = path.trim();

  // R Scripts.

  String ss = 'session_setup';
  // String dw = 'dataset_load_weather';
  String dfp = 'dataset_load_from_package';
  String dc = 'dataset_load_csv';
  String dx = 'dataset_load_txt';
  String dp = 'dataset_prep'; // Dataset cleaning and prepartion pre-template.

  if (path == '' && dataset.isEmpty && package.isEmpty) {
    // 20241007 gjw If no path is specified then we load the sample dataset from
    // Rattle. At this time through the GUI we do not have an empty path nor are
    // we using the rattle::weather dataset which is rather dated. So this
    // option is not currently utilised.
    path = weatherDemoFile;
  }

  if (isFromPackage(path)) {
    // load from package first
    if (context.mounted) await rSource(context, ref, [ss, dfp, dp]);
  } else if (path.endsWith('.csv')) {
    // 20241007 gjw We will load a CSV file into the R process. Note that we do
    // not yet run the DATA TEMPLATE as we need to first set up the ROLES. The
    // dataset template is run in `home.dart` on leaving the DATASET tab.

    if (context.mounted) await rSource(context, ref, [ss, dc, dp]);

    ref.read(datatypeProvider.notifier).state = 'table';
  } else if (path.endsWith('.txt')) {
    // 20241007 gjw We can also load a text file for the word cloud
    // functionality as a stop gap toward implementing more complete text mining
    // and language capabilities.

    if (context.mounted) await rSource(context, ref, [ss, dx]);

    ref.read(datatypeProvider.notifier).state = 'text';
  } else {
    // 20241007 gjw Through the GUI we don't expect to be able to reach here.

    debugPrint('LOAD_DATASET: PATH NOT RECOGNISED -> ABORT: $path.');

    showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text('PATH NOT RECOGNISED'),
        content: const Text('Unable to load dataset'),
        actions: <Widget>[
          ElevatedButton(
            child: const Text('OK'),
            onPressed: () => Navigator.of(context).pop(),
          ),
        ],
      ),
    );

    return;
  }

  debugText('R LOADED', path);

  return;
}