import React, { useEffect, useRef } from 'react'
import styled from 'styled-components'
import Split from 'split-grid'
import { ArrowDownIcon, Button, ChartIcon } from '@pancakeswap/uikit'
import debounce from 'lodash/debounce'
import delay from 'lodash/delay'
import { useAppDispatch } from 'state'
import { useGetPredictionsStatus, useIsChartPaneOpen, useIsHistoryPaneOpen } from 'state/hooks'
import { setChartPaneState } from 'state/predictions'
import { PredictionStatus } from 'state/types'
import { useTranslation } from 'contexts/Localization'
import TradingView from './components/TradingView'
import { ErrorNotification, PauseNotification } from './components/Notification'
import History from './History'
import Positions from './Positions'

// The value to set the chart when the user clicks the chart tab at the bottom
const GRID_TEMPLATE_ROW = '1.2fr 12px .8fr'

const ExpandChartButton = styled(Button)`
  background-color: ${({ theme }) => theme.card.background};
  border-bottom-left-radius: 0;
  border-bottom-right-radius: 0;
  bottom: 12px;
  color: ${({ theme }) => theme.colors.text};
  display: none;
  left: 32px;
  position: absolute;
  z-index: 50;

  &:hover:not(:disabled):not(.pancake-button--disabled):not(.pancake-button--disabled):not(:active) {
    background-color: ${({ theme }) => theme.card.background};
    opacity: 1;
  }

  ${({ theme }) => theme.mediaQueries.lg} {
    display: inline-flex;
  }
`

const SplitWrapper = styled.div`
  display: grid;
  grid-template-columns: 1fr;
  grid-template-rows: 1fr 12px 0;
  flex: 1;
  overflow: hidden;
`

const ChartPane = styled.div`
  overflow: hidden;
  position: relative;
`

const HistoryPane = styled.div<{ isHistoryPaneOpen: boolean }>`
  flex: none;
  overflow: hidden;
  transition: width 200ms ease-in-out;
  width: ${({ isHistoryPaneOpen }) => (isHistoryPaneOpen ? '384px' : 0)};
`

const StyledDesktop = styled.div`
  display: none;

  ${({ theme }) => theme.mediaQueries.lg} {
    display: flex;
    height: 100%;
  }
`

const PositionPane = styled.div`
  align-items: center;
  display: flex;
  max-width: 100%;
  overflow-y: auto;
  overflow-x: hidden;

  & > div {
    flex: 1;
    overflow: hidden;
  }
`

const Gutter = styled.div`
  background: ${({ theme }) => theme.colors.dropdown};
  cursor: row-resize;
  height: 12px;
  position: relative;

  &:before {
    background-color: ${({ theme }) => theme.colors.textSubtle};
    border-radius: 8px;
    content: '';
    height: 4px;
    left: 50%;
    margin-left: -32px;
    position: absolute;
    top: 4px;
    width: 64px;
  }
`

const Desktop: React.FC = () => {
  const splitWrapperRef = useRef<HTMLDivElement>()
  const chartRef = useRef<HTMLDivElement>()
  const gutterRef = useRef<HTMLDivElement>()
  const isHistoryPaneOpen = useIsHistoryPaneOpen()
  const isChartPaneOpen = useIsChartPaneOpen()
  const dispatch = useAppDispatch()
  const { t } = useTranslation()
  const status = useGetPredictionsStatus()

  const toggleChartPane = () => {
    const newChartPaneState = !isChartPaneOpen

    if (newChartPaneState) {
      splitWrapperRef.current.style.transition = 'grid-template-rows 150ms'
      splitWrapperRef.current.style.gridTemplateRows = GRID_TEMPLATE_ROW

      // Purely comedic: We only want to animate if we are clicking the open chart button
      // If we keep the transition on the resizing becomes very choppy
      delay(() => {
        splitWrapperRef.current.style.transition = ''
      }, 150)
    }

    dispatch(setChartPaneState(newChartPaneState))
  }

  useEffect(() => {
    const threshold = 100
    const handleDrag = debounce(() => {
      const { height } = chartRef.current.getBoundingClientRect()

      // If the height of the chart pane goes below the "snapOffset" threshold mark the chart pane as closed
      dispatch(setChartPaneState(height > threshold))
    }, 50)

    const split = Split({
      dragInterval: 1,
      snapOffset: threshold,
      onDrag: handleDrag,
      rowGutters: [
        {
          track: 1,
          element: gutterRef.current,
        },
      ],
    })

    return () => {
      split.destroy()
    }
  }, [gutterRef, chartRef, dispatch])

  return (
    <>
      {!isChartPaneOpen && (
        <ExpandChartButton
          variant="tertiary"
          scale="sm"
          startIcon={isChartPaneOpen ? <ArrowDownIcon /> : <ChartIcon />}
          onClick={toggleChartPane}
        >
          {isChartPaneOpen ? t('Close') : t('Charts')}
        </ExpandChartButton>
      )}
      <StyledDesktop>
        <SplitWrapper ref={splitWrapperRef}>
          <PositionPane>
            {status === PredictionStatus.ERROR && <ErrorNotification />}
            {status === PredictionStatus.PAUSED && <PauseNotification />}
            {status === PredictionStatus.LIVE && (
              <div>
                <Positions />
              </div>
            )}
          </PositionPane>
          <Gutter ref={gutterRef} />
          <ChartPane ref={chartRef}>
            <TradingView />
          </ChartPane>
        </SplitWrapper>
        <HistoryPane isHistoryPaneOpen={isHistoryPaneOpen}>
          <History />
        </HistoryPane>
      </StyledDesktop>
    </>
  )
}

export default Desktop