import $ from 'jquery'
import humps from 'humps'
import numeral from 'numeral'
import 'numeral/locales'
import socket from '../socket'
import router from '../router'
import { batchChannel, initRedux } from '../utils'

const BATCH_THRESHOLD = 10

export const initialState = {
  addressHash: null,
  batchCountAccumulator: 0,
  beyondPageOne: null,
  channelDisconnected: false,
  filter: null,
  newTransactions: [],
  balance: null,
  transactionCount: null
}

export function reducer (state = initialState, action) {
  switch (action.type) {
    case 'PAGE_LOAD': {
      return Object.assign({}, state, {
        addressHash: action.params.addressHash,
        beyondPageOne: !!action.params.blockNumber,
        filter: action.params.filter,
        transactionCount: numeral(action.transactionCount).value()
      })
    }
    case 'CHANNEL_DISCONNECTED': {
      if (state.beyondPageOne) return state

      return Object.assign({}, state, {
        channelDisconnected: true,
        batchCountAccumulator: 0
      })
    }
    case 'RECEIVED_UPDATED_BALANCE': {
      return Object.assign({}, state, {
        balance: action.msg.balance
      })
    }
    case 'RECEIVED_NEW_TRANSACTION_BATCH': {
      if (state.channelDisconnected || state.beyondPageOne) return state

      const incomingTransactions = humps.camelizeKeys(action.msgs)
        .filter(({toAddressHash, fromAddressHash}) => (
          !state.filter ||
          (state.filter === 'to' && toAddressHash === state.addressHash) ||
          (state.filter === 'from' && fromAddressHash === state.addressHash)
        ))

      if (!state.batchCountAccumulator && action.msgs.length < BATCH_THRESHOLD) {
        return Object.assign({}, state, {
          newTransactions: [
            ...state.newTransactions,
            ...incomingTransactions.map(({transactionHtml}) => transactionHtml)
          ],
          transactionCount: state.transactionCount + action.msgs.length
        })
      } else {
        return Object.assign({}, state, {
          batchCountAccumulator: state.batchCountAccumulator + action.msgs.length,
          transactionCount: state.transactionCount + action.msgs.length
        })
      }
    }
    default:
      return state
  }
}

router.when('/addresses/:addressHash').then((params) => initRedux(reducer, {
  main (store) {
    const { addressHash, blockNumber, locale } = params
    const channel = socket.channel(`addresses:${addressHash}`, {})
    numeral.locale(locale)
    store.dispatch({
      type: 'PAGE_LOAD',
      params,
      transactionCount: $('[data-selector="transaction-count"]').text()
    })
    channel.join()
    channel.onError(() => store.dispatch({ type: 'CHANNEL_DISCONNECTED' }))
    channel.on('balance', (msg) => store.dispatch({ type: 'RECEIVED_UPDATED_BALANCE', msg }))
    if (!blockNumber) channel.on('transaction', batchChannel((msgs) => store.dispatch({ type: 'RECEIVED_NEW_TRANSACTION_BATCH', msgs })))
  },
  render (state, oldState) {
    const $channelBatching = $('[data-selector="channel-batching-message"]')
    const $channelBatchingCount = $('[data-selector="channel-batching-count"]')
    const $channelDisconnected = $('[data-selector="channel-disconnected-message"]')
    const $emptyTransactionsList = $('[data-selector="empty-transactions-list"]')
    const $balance = $('[data-selector="balance-card"]')
    const $transactionCount = $('[data-selector="transaction-count"]')
    const $transactionsList = $('[data-selector="transactions-list"]')

    if ($emptyTransactionsList.length && state.newTransactions.length) window.location.reload()
    if (state.channelDisconnected) $channelDisconnected.show()
    if (oldState.balance !== state.balance) $balance.empty().append(state.balance)
    if (oldState.transactionCount !== state.transactionCount) $transactionCount.empty().append(numeral(state.transactionCount).format())
    if (state.batchCountAccumulator) {
      $channelBatching.show()
      $channelBatchingCount[0].innerHTML = numeral(state.batchCountAccumulator).format()
    } else {
      $channelBatching.hide()
    }
    if (oldState.newTransactions !== state.newTransactions && $transactionsList.length) {
      $transactionsList.prepend(state.newTransactions.slice(oldState.newTransactions.length).reverse().join(''))
    }
  }
}))