import React, { useCallback, useEffect } from 'react';
import { FormattedMessage, defineMessages, useIntl } from 'react-intl';

import { authorizeGroupMembershipRequest, fetchGroup, fetchGroupMembershipRequests, rejectGroupMembershipRequest } from 'soapbox/actions/groups';
import snackbar from 'soapbox/actions/snackbar';
import Account from 'soapbox/components/account';
import ScrollableList from 'soapbox/components/scrollable-list';
import { Button, Column, HStack, Spinner } from 'soapbox/components/ui';
import { useAppDispatch, useAppSelector } from 'soapbox/hooks';
import { makeGetAccount, makeGetGroup } from 'soapbox/selectors';

import ColumnForbidden from '../ui/components/column-forbidden';

type RouteParams = { id: string };

const messages = defineMessages({
  heading: { id: 'column.group_pending_requests', defaultMessage: 'Pending requests' },
  authorize: { id: 'group.group_mod_authorize', defaultMessage: 'Accept' },
  authorized: { id: 'group.group_mod_authorize.success', defaultMessage: 'Accepted @{name} to group' },
  reject: { id: 'group.group_mod_reject', defaultMessage: 'Reject' },
  rejected: { id: 'group.group_mod_reject.success', defaultMessage: 'Rejected @{name} from group' },
});

interface IMembershipRequest {
  accountId: string
  groupId: string
}

const MembershipRequest: React.FC<IMembershipRequest> = ({ accountId, groupId }) => {
  const intl = useIntl();
  const dispatch = useAppDispatch();

  const getAccount = useCallback(makeGetAccount(), []);

  const account = useAppSelector((state) => getAccount(state, accountId));

  if (!account) return null;

  const handleAuthorize = () =>
    dispatch(authorizeGroupMembershipRequest(groupId, accountId)).then(() => {
      dispatch(snackbar.success(intl.formatMessage(messages.authorized, { name: account.acct })));
    });

  const handleReject = () =>
    dispatch(rejectGroupMembershipRequest(groupId, accountId)).then(() => {
      dispatch(snackbar.success(intl.formatMessage(messages.rejected, { name: account.acct })));
    });

  return (
    <HStack space={1} alignItems='center' justifyContent='between' className='p-2.5'>
      <div className='w-full'>
        <Account account={account} withRelationship={false} />
      </div>
      <HStack space={2}>
        <Button
          theme='secondary'
          size='sm'
          text={intl.formatMessage(messages.authorize)}
          onClick={handleAuthorize}
        />
        <Button
          theme='danger'
          size='sm'
          text={intl.formatMessage(messages.reject)}
          onClick={handleReject}
        />
      </HStack>
    </HStack>
  );
};

interface IGroupMembershipRequests {
  params: RouteParams
}

const GroupMembershipRequests: React.FC<IGroupMembershipRequests> = ({ params }) => {
  const intl = useIntl();
  const dispatch = useAppDispatch();

  const id = params?.id || '';

  const getGroup = useCallback(makeGetGroup(), []);
  const group = useAppSelector(state => getGroup(state, id));
  const accountIds = useAppSelector((state) => state.user_lists.membership_requests.get(id)?.items);

  useEffect(() => {
    if (!group) dispatch(fetchGroup(id));
    dispatch(fetchGroupMembershipRequests(id));
  }, [id]);

  if (!group || !group.relationship || !accountIds) {
    return (
      <Column label={intl.formatMessage(messages.heading)}>
        <Spinner />
      </Column>
    );
  }

  if (!group.relationship.role || !['admin', 'moderator'].includes(group.relationship.role)) {
    return (<ColumnForbidden />);
  }

  const emptyMessage = <FormattedMessage id='empty_column.group_membership_requests' defaultMessage='There are no pending membership requests for this group.' />;

  return (
    <Column label={intl.formatMessage(messages.heading)} backHref={`/groups/${id}/manage`}>
      <ScrollableList
        scrollKey='group_membership_requests'
        emptyMessage={emptyMessage}
      >
        {accountIds.map((accountId) =>
          <MembershipRequest key={accountId} accountId={accountId} groupId={id} />,
        )}
      </ScrollableList>
    </Column>
  );
};

export default GroupMembershipRequests;