import * as React from 'react';
import { ContextualMenu, DefaultButton, IContextualMenuProps, IIconProps } from 'office-ui-fabric-react';

export interface IButtonExampleProps {
  // These are set based on the toggles shown above the examples (not needed in real code)
  disabled?: boolean;
  checked?: boolean;
}

const menuProps: IContextualMenuProps = {
  // For example: disable dismiss if shift key is held down while dismissing
  onDismiss: ev => {
    if (ev && ev.shiftKey) {
      ev.preventDefault();
    }
  },
  items: [
    {
      key: 'emailMessage',
      text: 'Email message',
      iconProps: { iconName: 'Mail' }
    },
    {
      key: 'calendarEvent',
      text: 'Calendar event',
      iconProps: { iconName: 'Calendar' }
    }
  ],
  directionalHintFixed: true
};
const addIcon: IIconProps = { iconName: 'Add' };

export const ButtonContextualMenuExample: React.FunctionComponent<IButtonExampleProps> = props => {
  const { disabled, checked } = props;

  return (
    <DefaultButton
      text="New item"
      iconProps={addIcon}
      menuProps={menuProps}
      // Optional callback to customize menu rendering
      menuAs={_getMenu}
      // Optional callback to do other actions (besides opening the menu) on click
      onMenuClick={_onMenuClick}
      // By default, the ContextualMenu is re-created each time it's shown and destroyed when closed.
      // Uncomment the next line to hide the ContextualMenu but persist it in the DOM instead.
      // persistMenu={true}
      allowDisabledFocus
      disabled={disabled}
      checked={checked}
    />
  );
};

function _getMenu(props: IContextualMenuProps): JSX.Element {
  // Customize contextual menu with menuAs
  return <ContextualMenu {...props} />;
}

function _onMenuClick(ev?: React.SyntheticEvent<any>) {
  console.log(ev);
}