// Copyright 2017-2025 @polkadot/app-staking-async authors & contributors
// SPDX-License-Identifier: Apache-2.0

import type { DeriveStakingOverview } from '@polkadot/api-derive/types';
import type { SortedTargets } from '@polkadot/app-staking/types';
import type { Option, u32 } from '@polkadot/types-codec';
import type { BN } from '@polkadot/util';

import React, { useEffect, useState } from 'react';

import { CardSummary, styled, SummaryBox } from '@polkadot/react-components';
import { useApi, useCall } from '@polkadot/react-hooks';
import { formatNumber } from '@polkadot/util';

import { useTranslation } from '../translate.js';
import SummarySession from './SummarySession.js';

interface Props {
  className?: string;
  nominators?: string[];
  stakingOverview?: DeriveStakingOverview;
  targets: SortedTargets;
}

const OPT_CURRENTERA = {
  transform: (currentEra: Option<u32>): BN | null =>
    currentEra.unwrapOr(null)
};

const useActiveNominators = () => {
  const { api } = useApi();
  const currentEra = useCall(api.query.staking.currentEra, undefined, OPT_CURRENTERA);
  const [exposedNominators, setExposedNominators] = useState<string[]>([]);

  useEffect(() => {
    const getExposedNominators = async () => {
      const exposedNominators = (await api.query.staking.erasStakersPaged.entries(currentEra)).map(([_, value]) => {
        // eslint-disable-next-line @typescript-eslint/ban-ts-comment
        // @ts-expect-error
        // eslint-disable-next-line @typescript-eslint/no-unsafe-return, @typescript-eslint/no-unsafe-call, @typescript-eslint/no-unsafe-member-access
        return (value).unwrap().others.map((x) => x.who.toString());
      }).flat();

      setExposedNominators([...new Set(exposedNominators)]);
    };

    getExposedNominators().catch(console.log);
  }, [api.query.staking.erasStakersPaged, currentEra]);

  return exposedNominators;
};

function Summary ({ className = '', stakingOverview, targets: { counterForNominators, inflation: { idealStake, inflation, stakedFraction }, waitingIds } }: Props): React.ReactElement<Props> {
  const { t } = useTranslation();

  const activeNominators = useActiveNominators();

  const percent = <span className='percent'>%</span>;

  return (
    <StyledSummaryBox className={className}>
      <section>
        <CardSummary label={t('validators')}>
          {stakingOverview
            ? <>{formatNumber(stakingOverview.validators.length)}&nbsp;/&nbsp;{formatNumber(stakingOverview.validatorCount)}</>
            : <span className='--tmp'>999 / 999</span>
          }
        </CardSummary>
        <CardSummary
          className='media--900'
          label={t('waiting')}
        >
          {waitingIds
            ? formatNumber(waitingIds.length)
            : <span className='--tmp'>99</span>
          }
        </CardSummary>
        <CardSummary
          className='media--1000'
          label={
            counterForNominators
              ? t('active / nominators')
              : t('nominators')
          }
        >
          {activeNominators
            ? (
              <>
                {formatNumber(activeNominators.length)}
                {counterForNominators && (
                  <>&nbsp;/&nbsp;{formatNumber(counterForNominators)}</>
                )}
              </>
            )
            : <span className='--tmp'>999 / 999</span>
          }
        </CardSummary>
      </section>
      <section>
        {(idealStake > 0) && Number.isFinite(idealStake) && (
          <CardSummary
            className='media--1400'
            label={t('ideal staked')}
          >
            <>{(idealStake * 100).toFixed(1)}{percent}</>
          </CardSummary>
        )}
        {(stakedFraction > 0) && (
          <CardSummary
            className='media--1300'
            label={t('staked')}
          >
            <>{(stakedFraction * 100).toFixed(1)}{percent}</>
          </CardSummary>
        )}
        {(inflation > 0) && Number.isFinite(inflation) && (
          <CardSummary
            className='media--1200'
            label={t('inflation')}
          >
            <>{inflation.toFixed(1)}{percent}</>
          </CardSummary>
        )}
      </section>
      <section>
        <SummarySession />
      </section>
    </StyledSummaryBox>
  );
}

const StyledSummaryBox = styled(SummaryBox)`
  .validator--Account-block-icon {
    display: inline-block;
    margin-right: 0.75rem;
    margin-top: -0.25rem;
    vertical-align: middle;
  }

  .validator--Summary-authors {
    .validator--Account-block-icon+.validator--Account-block-icon {
      margin-left: -1.5rem;
    }
  }

  .percent {
    font-size: var(--font-percent-tiny);
  }
`;

export default React.memo(Summary);