Extension

main.dart

void main() {
  print(' NOTA SALES '.center(25, '='));
  print('Ayam Goreng Special Pedas'.width(15) + '10'.width(5) + '32,000'.width(7));
  print('www.uniq.id'.center(25, ' '));
}

extension StringExtensions on String {
  String loop(int w) {
    var newVal = '';
    for (var i = 0; i < w; i++) {
      newVal += this;
    }
    return newVal;
  }

  String width(int width, {int max = 32, int before = 0}) {
    try {
      var cursor = 0;
      var wordSplit = StringBuffer();
      do {
        var suffix = '';
        var start = cursor; 
        var end = (start + width) < length ? start + width : length;
        var cutWord = substring(start, end);  
        var lastSpace = cutWord.contains(' ') && end != length 
          ? cutWord.lastIndexOf(' ')
          : cutWord.length;

        if (lastSpace < (width~/2) && (width - 1) < cutWord.length) {
          lastSpace = width - 1;
          cursor--;
          suffix = '-';
        }

        cursor += lastSpace + 1;
        suffix += cursor < length  
          ? ' '.padRight(max - (before + lastSpace)) + '\n'
          : ' '.padRight(width - (before + lastSpace));
        
        wordSplit.write(cutWord.substring(0, lastSpace) + suffix);
      } while(cursor < length);

      return wordSplit.toString();
      
    } catch (e) {
      // Handle error
    }

    // Fallback logic    
    return padRight(width); 
  }


  String widthRight(int w) {
    return padLeft(w); 
  }


  String center(int width, [String flanks = ' ']) {
    if (length == width) {
      return this;
    } else if (length < width) {  
      var center = width~/2;
      var flank = center - (length~/2);
      
      var newValue = StringBuffer();
      for (var i = 0; i < flank; i++) {
        newValue.write(flanks);  
      }
      newValue.write(this);

      for (var i = newValue.length; i < width; i++) {
        newValue.write(flanks);  
      }
      return newValue.toString();

    } else {
      // Handle case where length > width
    }

    return '';
  }
  
}