// @flow strict

import * as React from 'react';
import {
  // $FlowFixMe[untyped-import]
  autoUpdate,
  // $FlowFixMe[untyped-import]
  flip,
  // $FlowFixMe[untyped-import]
  offset,
  // $FlowFixMe[untyped-import]
  useFloating,
} from '@floating-ui/react-dom';

import {colorBackgroundTertiary} from '../../styles/variables/_color';
import {sizeFluid} from '../../styles/variables/_size';
import {spaceNone, spaceXXSmall} from '../../styles/variables/_space';
import {classify} from '../../utils/classify';
import {ClickAway} from '../../utils/click-away';
import type {InputProps} from '../Input';
import {Input} from '../Input';
import type {MenuOption, MenuProps} from '../Menu';
import {Menu} from '../Menu';

import css from './Dropdown.module.css';


type ClassNames = $ReadOnly<{wrapper?: string, box?: string}>;

export type DropdownProps = {
  ...InputProps,
  classNames?: ClassNames,
  onChange?: (option: MenuOption) => mixed,
  onMenuOpen?: () => mixed,
  onMenuClose?: () => mixed,
  dropdownInputText?: string,
  menu?: MenuProps,
  ...
};

export const Dropdown: React$AbstractComponent<
  DropdownProps,
  HTMLInputElement,
> = React.forwardRef<DropdownProps, HTMLInputElement>(
  (
    {
      size = 'medium',
      classNames,
      placeholder = 'Select...',
      onChange,
      menu,
      onMenuOpen,
      onMenuClose,
      dropdownInputText = '',
      ...inputProps
    }: DropdownProps,
    ref,
  ): React.Node => {
    const dropdownRef = React.useRef();
    const {x, y, reference, floating, strategy} = useFloating({
      strategy: 'absolute',
      placement: 'bottom-start',
      whileElementsMounted: autoUpdate,
      middleware: [flip(), offset(parseInt(spaceXXSmall))],
    });

    const onMenuToggle = (isOpen: boolean) => {
      isOpen ? onMenuOpen && onMenuOpen() : onMenuClose && onMenuClose();
    };

    return (
      <ClickAway onChange={onMenuToggle}>
        {({isOpen, onOpen, cancelNext, clickAway}) => (
          <div
            data-testid="Dropdown"
            className={classify(css.dropdownContainer, classNames?.wrapper)}
            ref={dropdownRef}
          >
            <Input
              {...inputProps}
              boxRef={reference}
              size={size}
              placeholder={placeholder}
              value={dropdownInputText}
              classNames={{box: css.inputBox}}
              iconRightName={isOpen ? 'angle-up' : 'angle-down'}
              readOnly
              onContainerClick={(e) => {
                e.stopPropagation();
                onOpen();
              }}
              ref={ref}
            />

            {isOpen && menu && (
              <div
                onClickCapture={cancelNext}
                ref={floating}
                style={{
                  position: strategy,
                  top: y ?? spaceNone,
                  left: x ?? spaceNone,
                  width: sizeFluid,
                  backgroundColor: colorBackgroundTertiary,
                }}
              >
                <Menu
                  {...menu}
                  onSelect={(option) => {
                    onChange && onChange(option);
                    if (
                      !menu.optionsVariant ||
                      menu.optionsVariant === 'normal'
                    ) {
                      clickAway();
                    }
                  }}
                  size={menu.size || size}
                />
              </div>
            )}
          </div>
        )}
      </ClickAway>
    );
  },
);