/* eslint no-param-reassign: ["error", { "props": false }] */

const bridgeValidatorsAbi = require('../../contracts/build/contracts/BridgeValidators').abi
const logger = require('../logger')('validatorsUtils')
const { getPastEvents } = require('./contract')

const parseValidatorEvent = event => {
  if (
    event.event === undefined &&
    event.raw &&
    event.raw.topics &&
    (event.raw.topics[0] === '0xe366c1c0452ed8eec96861e9e54141ebff23c9ec89fe27b996b45f5ec3884987' ||
      event.raw.topics[0] === '0x8064a302796c89446a96d63470b5b036212da26bd2debe5bec73e0170a9a5e83')
  ) {
    const rawAddress = event.raw.topics.length > 1 ? event.raw.topics[1] : event.raw.data
    const address = '0x' + rawAddress.slice(26)
    event.event = 'ValidatorAdded'
    event.returnValues.validator = address
  } else if (
    event.event === undefined &&
    event.raw &&
    event.raw.topics &&
    event.raw.topics[0] === '0xe1434e25d6611e0db941968fdc97811c982ac1602e951637d206f5fdda9dd8f1'
  ) {
    const rawAddress = event.raw.data === '0x' ? event.raw.topics[1] : event.raw.data
    const address = '0x' + rawAddress.slice(26)
    event.event = 'ValidatorRemoved'
    event.returnValues.validator = address
  }
}

const processValidatorsEvents = events => {
  const validatorList = new Set()
  events.forEach(event => {
    parseValidatorEvent(event)

    if (event.event === 'ValidatorAdded') {
      validatorList.add(event.returnValues.validator)
    } else if (event.event === 'ValidatorRemoved') {
      validatorList.delete(event.returnValues.validator)
    }
  })

  return Array.from(validatorList)
}

const validatorList = async contract => {
  try {
    return await contract.methods.validatorList().call()
  } catch (e) {
    return []
  }
}

const getValidatorList = async (address, eth, fromBlock, toBlock) => {
  logger.debug('getting validatorList')
  const validatorsContract = new eth.Contract(bridgeValidatorsAbi, address)
  const validators = await validatorList(validatorsContract)

  if (validators.length) {
    return validators
  }

  logger.debug('getting validatorsEvents')
  const contract = new eth.Contract([], address)
  const validatorsEvents = await getPastEvents({
    contract,
    event: 'allEvents',
    fromBlock,
    toBlock,
    options: {}
  })

  return processValidatorsEvents(validatorsEvents)
}

module.exports = {
  getValidatorList
}