import { stripHexPrefix, addHexPrefix } from 'ethereumjs-util'
import { createSelector } from 'reselect'
import { NETWORK_TYPES } from '../helpers/constants/common'
import {
  shortenAddress,
  checksumAddress,
  getAccountByAddress,
} from '../helpers/utils/util'
import { getPermissionsRequestCount } from './permissions'

export function getNetworkIdentifier (state) {
  const { metamask: { provider: { type, nickname, rpcUrl } } } = state

  return nickname || rpcUrl || type
}

export function getCurrentKeyring (state) {
  const identity = getSelectedIdentity(state)

  if (!identity) {
    return null
  }

  const simpleAddress = stripHexPrefix(identity.address).toLowerCase()

  const keyring = state.metamask.keyrings.find((kr) => {
    return kr.accounts.includes(simpleAddress) ||
      kr.accounts.includes(identity.address)
  })

  return keyring
}

export function getAccountType (state) {
  const currentKeyring = getCurrentKeyring(state)
  const type = currentKeyring && currentKeyring.type

  switch (type) {
    case 'Trezor Hardware':
    case 'Ledger Hardware':
      return 'hardware'
    case 'Simple Key Pair':
      return 'imported'
    default:
      return 'default'
  }
}

export function getCurrentNetworkId (state) {
  return state.metamask.network
}

export const getMetaMaskAccounts = createSelector(
  getMetaMaskAccountsRaw,
  getMetaMaskCachedBalances,
  (currentAccounts, cachedBalances) => Object.entries(currentAccounts).reduce((selectedAccounts, [accountID, account]) => {
    if (account.balance === null || account.balance === undefined) {
      return {
        ...selectedAccounts,
        [accountID]: {
          ...account,
          balance: cachedBalances && cachedBalances[accountID],
        },

      }
    }
    return {
      ...selectedAccounts,
      [accountID]: account,
    }
  }, {}),
)

export function getSelectedAddress (state) {
  return state.metamask.selectedAddress
}

export function getSelectedIdentity (state) {
  const selectedAddress = getSelectedAddress(state)
  const { identities } = state.metamask

  return identities[selectedAddress]
}

export function getNumberOfAccounts (state) {
  return Object.keys(state.metamask.accounts).length
}

export function getNumberOfTokens (state) {
  const { tokens } = state.metamask
  return tokens ? tokens.length : 0
}

export function getMetaMaskKeyrings (state) {
  return state.metamask.keyrings
}

export function getMetaMaskIdentities (state) {
  return state.metamask.identities
}

export function getMetaMaskAccountsRaw (state) {
  return state.metamask.accounts
}

export function getMetaMaskCachedBalances (state) {
  const network = getCurrentNetworkId(state)

  return state.metamask.cachedBalances[network]
}

/**
 * Get ordered (by keyrings) accounts with identity and balance
 */
export const getMetaMaskAccountsOrdered = createSelector(
  getMetaMaskKeyrings,
  getMetaMaskIdentities,
  getMetaMaskAccounts,
  (keyrings, identities, accounts) => keyrings
    .reduce((list, keyring) => list.concat(keyring.accounts), [])
    .filter((address) => Boolean(identities[address]))
    .map((address) => ({ ...identities[address], ...accounts[address] })),
)

export function isBalanceCached (state) {
  const selectedAccountBalance = state.metamask.accounts[getSelectedAddress(state)].balance
  const cachedBalance = getSelectedAccountCachedBalance(state)

  return Boolean(!selectedAccountBalance && cachedBalance)
}

export function getSelectedAccountCachedBalance (state) {
  const cachedBalances = state.metamask.cachedBalances[state.metamask.network]
  const selectedAddress = getSelectedAddress(state)

  return cachedBalances && cachedBalances[selectedAddress]
}

export function getSelectedAccount (state) {
  const accounts = getMetaMaskAccounts(state)
  const selectedAddress = getSelectedAddress(state)

  return accounts[selectedAddress]
}

export function getTargetAccount (state, targetAddress) {
  const accounts = getMetaMaskAccounts(state)
  return accounts[targetAddress]
}

export const getTokenExchangeRates = (state) => state.metamask.contractExchangeRates

export function getAssetImages (state) {
  const assetImages = state.metamask.assetImages || {}
  return assetImages
}

export function getAddressBook (state) {
  const { network } = state.metamask
  if (!state.metamask.addressBook[network]) {
    return []
  }
  return Object.values(state.metamask.addressBook[network])
}

export function getAddressBookEntry (state, address) {
  const addressBook = getAddressBook(state)
  const entry = addressBook.find((contact) => contact.address === checksumAddress(address))
  return entry
}

export function getAddressBookEntryName (state, address) {
  const entry = getAddressBookEntry(state, address) || state.metamask.identities[address]
  return entry && entry.name !== '' ? entry.name : shortenAddress(address)
}

export function accountsWithSendEtherInfoSelector (state) {
  const accounts = getMetaMaskAccounts(state)
  const identities = getMetaMaskIdentities(state)

  const accountsWithSendEtherInfo = Object.entries(identities).map(([key, identity]) => {
    return { ...identity, ...accounts[key] }
  })

  return accountsWithSendEtherInfo
}

export function getAccountsWithLabels (state) {
  return getMetaMaskAccountsOrdered(state).map(({ address, name, balance }) => ({
    address,
    addressLabel: `${name} (...${address.slice(address.length - 4)})`,
    label: name,
    balance,
  }))
}

export function getCurrentAccountWithSendEtherInfo (state) {
  const currentAddress = getSelectedAddress(state)
  const accounts = accountsWithSendEtherInfoSelector(state)

  return getAccountByAddress(accounts, currentAddress)
}

export function getTargetAccountWithSendEtherInfo (state, targetAddress) {
  const accounts = accountsWithSendEtherInfoSelector(state)
  return getAccountByAddress(accounts, targetAddress)
}

export function getCurrentEthBalance (state) {
  return getCurrentAccountWithSendEtherInfo(state).balance
}

export function getGasIsLoading (state) {
  return state.appState.gasIsLoading
}

export function getCurrentCurrency (state) {
  return state.metamask.currentCurrency
}

export function getTotalUnapprovedCount (state) {
  const {
    unapprovedMsgCount = 0,
    unapprovedPersonalMsgCount = 0,
    unapprovedDecryptMsgCount = 0,
    unapprovedEncryptionPublicKeyMsgCount = 0,
    unapprovedTypedMessagesCount = 0,
  } = state.metamask

  return unapprovedMsgCount + unapprovedPersonalMsgCount + unapprovedDecryptMsgCount +
    unapprovedEncryptionPublicKeyMsgCount + unapprovedTypedMessagesCount +
    getUnapprovedTxCount(state) + getPermissionsRequestCount(state) + getSuggestedTokenCount(state)
}

function getUnapprovedTxCount (state) {
  const { unapprovedTxs = {} } = state.metamask
  return Object.keys(unapprovedTxs).length
}

function getSuggestedTokenCount (state) {
  const { suggestedTokens = {} } = state.metamask
  return Object.keys(suggestedTokens).length
}

export function getIsMainnet (state) {
  const networkType = getNetworkIdentifier(state)
  return networkType === NETWORK_TYPES.MAINNET
}

export function isEthereumNetwork (state) {
  const networkType = getNetworkIdentifier(state)
  const {
    KOVAN,
    MAINNET,
    RINKEBY,
    ROPSTEN,
    GOERLI,
  } = NETWORK_TYPES

  return [KOVAN, MAINNET, RINKEBY, ROPSTEN, GOERLI].includes(networkType)
}

export function getPreferences ({ metamask }) {
  return metamask.preferences
}

export function getShouldShowFiat (state) {
  const isMainNet = getIsMainnet(state)
  const { showFiatInTestnets } = getPreferences(state)
  return Boolean(isMainNet || showFiatInTestnets)
}

export function getAdvancedInlineGasShown (state) {
  return Boolean(state.metamask.featureFlags.advancedInlineGas)
}

export function getUseNonceField (state) {
  return Boolean(state.metamask.useNonceField)
}

export function getCustomNonceValue (state) {
  return String(state.metamask.customNonceValue)
}

export function getDomainMetadata (state) {
  return state.metamask.domainMetadata
}

export const getBackgroundMetaMetricState = (state) => {
  return {
    network: getCurrentNetworkId(state),
    accountType: getAccountType(state),
    metaMetricsId: state.metamask.metaMetricsId,
    numberOfTokens: getNumberOfTokens(state),
    numberOfAccounts: getNumberOfAccounts(state),
    participateInMetaMetrics: state.metamask.participateInMetaMetrics,
  }
}

export function getRpcPrefsForCurrentProvider (state) {
  const { frequentRpcListDetail, provider } = state.metamask
  const selectRpcInfo = frequentRpcListDetail.find((rpcInfo) => rpcInfo.rpcUrl === provider.rpcUrl)
  const { rpcPrefs = {} } = selectRpcInfo || {}
  return rpcPrefs
}

export function getKnownMethodData (state, data) {
  if (!data) {
    return null
  }
  const prefixedData = addHexPrefix(data)
  const fourBytePrefix = prefixedData.slice(0, 10)
  const { knownMethodData } = state.metamask

  return knownMethodData && knownMethodData[fourBytePrefix]
}

export function getFeatureFlags (state) {
  return state.metamask.featureFlags
}

export function getOriginOfCurrentTab (state) {
  return state.activeTab.origin
}

export function getIpfsGateway (state) {
  return state.metamask.ipfsGateway
}