```typescript
/**
 * Split one line of CSV into its fields on commas.
 * A field wrapped in double quotes may contain commas, and a doubled quote inside such a field means one literal quote character;
 * the surrounding quotes are not part of the value. Fields that are not quoted are taken literally, including any surrounding spaces.
 * An empty line is one empty field.
 */
export function parseCsvLine(line: string): string[] {
  const result: string[] = [];
  let currentField: string | null = null;
  let inQuote: boolean = false;

  for (const char of line) {
    if (char === '"') {
      if (currentField === null || !inQuote) {
        throw new Error('Unbalanced quotes');
      }
      inQuote = !inQuote;
    } else if (!inQuote && char === ',') {
      result.push(currentField ?? '');
      currentField = null;
    } else {
      currentField = (currentField === null ? '' : currentField) + char;
    }
  }

  throw new Error('Unbalanced quotes');
}
```