import { chakra, Box, Flex, Text, VStack } from '@chakra-ui/react';
import { useQueryClient } from '@tanstack/react-query';
import React from 'react';

import type { SocketMessage } from 'lib/socket/types';
import type { Block } from 'types/api/block';

import { route } from 'nextjs-routes';

import config from 'configs/app';
import useApiQuery, { getResourceKey } from 'lib/api/useApiQuery';
import useInitialList from 'lib/hooks/useInitialList';
import useIsMobile from 'lib/hooks/useIsMobile';
import { nbsp } from 'lib/html-entities';
import useSocketChannel from 'lib/socket/useSocketChannel';
import useSocketMessage from 'lib/socket/useSocketMessage';
import { BLOCK } from 'stubs/block';
import { HOMEPAGE_STATS } from 'stubs/stats';
import { Heading } from 'toolkit/chakra/heading';
import { Skeleton } from 'toolkit/chakra/skeleton';
import LinkInternal from 'ui/shared/links/LinkInternal';

import LatestBlocksItem from './LatestBlocksItem';

const LatestBlocks = () => {
  const isMobile = useIsMobile();
  // const blocksMaxCount = isMobile ? 2 : 3;
  let blocksMaxCount: number;
  if (config.features.rollup.isEnabled || config.UI.views.block.hiddenFields?.total_reward) {
    blocksMaxCount = isMobile ? 4 : 5;
  } else {
    blocksMaxCount = isMobile ? 2 : 3;
  }
  const { data, isPlaceholderData, isError } = useApiQuery('homepage_blocks', {
    queryOptions: {
      placeholderData: Array(blocksMaxCount).fill(BLOCK),
    },
  });
  const initialList = useInitialList({
    data: data ?? [],
    idFn: (block) => block.height,
    enabled: !isPlaceholderData,
  });

  const queryClient = useQueryClient();
  const statsQueryResult = useApiQuery('stats', {
    queryOptions: {
      refetchOnMount: false,
      placeholderData: HOMEPAGE_STATS,
    },
  });

  const handleNewBlockMessage: SocketMessage.NewBlock['handler'] = React.useCallback((payload) => {
    queryClient.setQueryData(getResourceKey('homepage_blocks'), (prevData: Array<Block> | undefined) => {

      const newData = prevData ? [ ...prevData ] : [];

      if (newData.some((block => block.height === payload.block.height))) {
        return newData;
      }

      return [ payload.block, ...newData ].sort((b1, b2) => b2.height - b1.height).slice(0, blocksMaxCount);
    });
  }, [ queryClient, blocksMaxCount ]);

  const channel = useSocketChannel({
    topic: 'blocks:new_block',
    isDisabled: isPlaceholderData || isError,
  });
  useSocketMessage({
    channel,
    event: 'new_block',
    handler: handleNewBlockMessage,
  });

  let content;

  if (isError) {
    content = <Text>No data. Please reload the page.</Text>;
  }

  if (data) {
    const dataToShow = data.slice(0, blocksMaxCount);

    content = (
      <>
        <VStack gap={ 2 } mb={ 3 } overflow="hidden" alignItems="stretch">
          { dataToShow.map(((block, index) => (
            <LatestBlocksItem
              key={ block.height + (isPlaceholderData ? String(index) : '') }
              block={ block }
              isLoading={ isPlaceholderData }
              isNew={ initialList.isNew(block) }
            />
          ))) }
        </VStack>
        <Flex justifyContent="center">
          <LinkInternal fontSize="sm" href={ route({ pathname: '/blocks' }) }>View all blocks</LinkInternal>
        </Flex>
      </>
    );
  }

  return (
    <Box width={{ base: '100%', lg: '280px' }} flexShrink={ 0 }>
      <Heading level="3" mb={ 3 }>Latest blocks</Heading>
      { statsQueryResult.data?.network_utilization_percentage !== undefined && (
        <Skeleton loading={ statsQueryResult.isPlaceholderData } mt={ 1 } display="inline-block">
          <Text as="span" fontSize="sm">
            Network utilization:{ nbsp }
          </Text>
          <Text as="span" fontSize="sm" color="blue.400" fontWeight={ 700 }>
            { statsQueryResult.data?.network_utilization_percentage.toFixed(2) }%
          </Text>
        </Skeleton>
      ) }
      { statsQueryResult.data?.celo && (
        <Box whiteSpace="pre-wrap" fontSize="sm">
          <span>Current epoch: </span>
          <chakra.span fontWeight={ 700 }>#{ statsQueryResult.data.celo.epoch_number }</chakra.span>
        </Box>
      ) }
      <Box mt={ 3 }>
        { content }
      </Box>
    </Box>
  );
};

export default LatestBlocks;
