import { useDayPicker } from 'contexts/DayPicker';
import { useSelectMultiple } from 'contexts/SelectMultiple';
import { useSelectRange } from 'contexts/SelectRange';
import { useSelectSingle } from 'contexts/SelectSingle';
import { isDayPickerMultiple } from 'types/DayPickerMultiple';
import { isDayPickerRange } from 'types/DayPickerRange';
import { isDayPickerSingle } from 'types/DayPickerSingle';
import { DateRange } from 'types/Matchers';

export type SelectedDays = Date | Date[] | DateRange | undefined;

/**
 * Return the current selected days when DayPicker is in selection mode. Days
 * selected by the custom selection mode are not returned.
 *
 * This hook is meant to be used inside internal or custom components.
 *
 */
export function useSelectedDays(): SelectedDays {
  const dayPicker = useDayPicker();
  const single = useSelectSingle();
  const multiple = useSelectMultiple();
  const range = useSelectRange();

  const selectedDays = isDayPickerSingle(dayPicker)
    ? single.selected
    : isDayPickerMultiple(dayPicker)
    ? multiple.selected
    : isDayPickerRange(dayPicker)
    ? range.selected
    : undefined;

  return selectedDays;
}