import { Context, ReactNode, useCallback, useState } from 'react';
import styled from '@emotion/styled';

import { FilterDropdownButton } from '@/ui/filter-n-sort/components/FilterDropdownButton';
import SortAndFilterBar from '@/ui/filter-n-sort/components/SortAndFilterBar';
import { SortDropdownButton } from '@/ui/filter-n-sort/components/SortDropdownButton';
import { FiltersHotkeyScope } from '@/ui/filter-n-sort/types/FiltersHotkeyScope';
import { SelectedSortType, SortType } from '@/ui/filter-n-sort/types/interface';
import { TopBar } from '@/ui/top-bar/TopBar';

type OwnProps<SortField> = {
  viewName: string;
  viewIcon?: ReactNode;
  availableSorts?: Array<SortType<SortField>>;
  onSortsUpdate?: (sorts: Array<SelectedSortType<SortField>>) => void;
  context: Context<string | null>;
};

const StyledIcon = styled.div`
  display: flex;
  margin-left: ${({ theme }) => theme.spacing(1)};
  margin-right: ${({ theme }) => theme.spacing(2)};

  & > svg {
    font-size: ${({ theme }) => theme.icon.size.sm};
  }
`;

export function BoardHeader<SortField>({
  viewName,
  viewIcon,
  availableSorts,
  onSortsUpdate,
  context,
}: OwnProps<SortField>) {
  const [sorts, innerSetSorts] = useState<Array<SelectedSortType<SortField>>>(
    [],
  );

  const sortSelect = useCallback(
    (newSort: SelectedSortType<SortField>) => {
      const newSorts = updateSortOrFilterByKey(sorts, newSort);
      innerSetSorts(newSorts);
      onSortsUpdate && onSortsUpdate(newSorts);
    },
    [onSortsUpdate, sorts],
  );

  const sortUnselect = useCallback(
    (sortKey: string) => {
      const newSorts = sorts.filter((sort) => sort.key !== sortKey);
      innerSetSorts(newSorts);
      onSortsUpdate && onSortsUpdate(newSorts);
    },
    [onSortsUpdate, sorts],
  );

  return (
    <TopBar
      leftComponent={
        <>
          <StyledIcon>{viewIcon}</StyledIcon>
          {viewName}
        </>
      }
      rightComponent={
        <>
          <FilterDropdownButton
            context={context}
            HotkeyScope={FiltersHotkeyScope.FilterDropdownButton}
          />
          <SortDropdownButton<SortField>
            isSortSelected={sorts.length > 0}
            availableSorts={availableSorts || []}
            onSortSelect={sortSelect}
            HotkeyScope={FiltersHotkeyScope.FilterDropdownButton}
          />
        </>
      }
      bottomComponent={
        <SortAndFilterBar
          context={context}
          sorts={sorts}
          onRemoveSort={sortUnselect}
          onCancelClick={() => {
            innerSetSorts([]);
            onSortsUpdate && onSortsUpdate([]);
          }}
        />
      }
    />
  );
}

function updateSortOrFilterByKey<SortOrFilter extends { key: string }>(
  sorts: Readonly<SortOrFilter[]>,
  newSort: SortOrFilter,
): SortOrFilter[] {
  const newSorts = [...sorts];
  const existingSortIndex = sorts.findIndex((sort) => sort.key === newSort.key);

  if (existingSortIndex !== -1) {
    newSorts[existingSortIndex] = newSort;
  } else {
    newSorts.push(newSort);
  }

  return newSorts;
}
