import { clone, uniqBy, flatten } from 'ramda' import BigNumber from 'bignumber.js' import { loadLocalStorageData, saveLocalStorageData, } from '../../lib/local-storage-helpers' // Actions const BASIC_GAS_ESTIMATE_LOADING_FINISHED = 'metamask/gas/BASIC_GAS_ESTIMATE_LOADING_FINISHED' const BASIC_GAS_ESTIMATE_LOADING_STARTED = 'metamask/gas/BASIC_GAS_ESTIMATE_LOADING_STARTED' const GAS_ESTIMATE_LOADING_FINISHED = 'metamask/gas/GAS_ESTIMATE_LOADING_FINISHED' const GAS_ESTIMATE_LOADING_STARTED = 'metamask/gas/GAS_ESTIMATE_LOADING_STARTED' const RESET_CUSTOM_GAS_STATE = 'metamask/gas/RESET_CUSTOM_GAS_STATE' const RESET_CUSTOM_DATA = 'metamask/gas/RESET_CUSTOM_DATA' const SET_BASIC_GAS_ESTIMATE_DATA = 'metamask/gas/SET_BASIC_GAS_ESTIMATE_DATA' const SET_CUSTOM_GAS_ERRORS = 'metamask/gas/SET_CUSTOM_GAS_ERRORS' const SET_CUSTOM_GAS_LIMIT = 'metamask/gas/SET_CUSTOM_GAS_LIMIT' const SET_CUSTOM_GAS_PRICE = 'metamask/gas/SET_CUSTOM_GAS_PRICE' const SET_CUSTOM_GAS_TOTAL = 'metamask/gas/SET_CUSTOM_GAS_TOTAL' const SET_PRICE_AND_TIME_ESTIMATES = 'metamask/gas/SET_PRICE_AND_TIME_ESTIMATES' const SET_API_ESTIMATES_LAST_RETRIEVED = 'metamask/gas/SET_API_ESTIMATES_LAST_RETRIEVED' const SET_BASIC_API_ESTIMATES_LAST_RETRIEVED = 'metamask/gas/SET_BASIC_API_ESTIMATES_LAST_RETRIEVED' // TODO: determine if this approach to initState is consistent with conventional ducks pattern const initState = { customData: { price: null, limit: '0x5208', }, basicEstimates: { average: null, fastestWait: null, fastWait: null, fast: null, safeLowWait: null, blockNum: null, avgWait: null, blockTime: null, speed: null, fastest: null, safeLow: null, }, basicEstimateIsLoading: true, gasEstimatesLoading: true, priceAndTimeEstimates: [], basicPriceAndTimeEstimates: [], priceAndTimeEstimatesLastRetrieved: 0, basicPriceAndTimeEstimatesLastRetrieved: 0, errors: {}, } // Reducer export default function reducer ({ gas: gasState = initState }, action = {}) { const newState = clone(gasState) switch (action.type) { case BASIC_GAS_ESTIMATE_LOADING_STARTED: return { ...newState, basicEstimateIsLoading: true, } case BASIC_GAS_ESTIMATE_LOADING_FINISHED: return { ...newState, basicEstimateIsLoading: false, } case GAS_ESTIMATE_LOADING_STARTED: return { ...newState, gasEstimatesLoading: true, } case GAS_ESTIMATE_LOADING_FINISHED: return { ...newState, gasEstimatesLoading: false, } case SET_BASIC_GAS_ESTIMATE_DATA: return { ...newState, basicEstimates: action.value, } case SET_CUSTOM_GAS_PRICE: return { ...newState, customData: { ...newState.customData, price: action.value, }, } case SET_CUSTOM_GAS_LIMIT: return { ...newState, customData: { ...newState.customData, limit: action.value, }, } case SET_CUSTOM_GAS_TOTAL: return { ...newState, customData: { ...newState.customData, total: action.value, }, } case SET_PRICE_AND_TIME_ESTIMATES: return { ...newState, priceAndTimeEstimates: action.value, } case SET_CUSTOM_GAS_ERRORS: return { ...newState, errors: { ...newState.errors, ...action.value, }, } case SET_API_ESTIMATES_LAST_RETRIEVED: return { ...newState, priceAndTimeEstimatesLastRetrieved: action.value, } case SET_BASIC_API_ESTIMATES_LAST_RETRIEVED: return { ...newState, basicPriceAndTimeEstimatesLastRetrieved: action.value, } case RESET_CUSTOM_DATA: return { ...newState, customData: clone(initState.customData), } case RESET_CUSTOM_GAS_STATE: return clone(initState) default: return newState } } // Action Creators export function basicGasEstimatesLoadingStarted () { return { type: BASIC_GAS_ESTIMATE_LOADING_STARTED, } } export function basicGasEstimatesLoadingFinished () { return { type: BASIC_GAS_ESTIMATE_LOADING_FINISHED, } } export function gasEstimatesLoadingStarted () { return { type: GAS_ESTIMATE_LOADING_STARTED, } } export function gasEstimatesLoadingFinished () { return { type: GAS_ESTIMATE_LOADING_FINISHED, } } export function fetchBasicGasEstimates () { return (dispatch) => { dispatch(basicGasEstimatesLoadingStarted()) return fetch('https://dev.blockscale.net/api/gasexpress.json', { 'headers': {}, 'referrer': 'https://dev.blockscale.net/api/', 'referrerPolicy': 'no-referrer-when-downgrade', 'body': null, 'method': 'GET', 'mode': 'cors'} ) .then(r => r.json()) .then(({ safeLow, standard: average, fast, fastest, block_time: blockTime, blockNum, }) => { const basicEstimates = { safeLow, average, fast, fastest, blockTime, blockNum, } dispatch(setBasicGasEstimateData(basicEstimates)) dispatch(basicGasEstimatesLoadingFinished()) return basicEstimates }) } } export function fetchBasicGasAndTimeEstimates () { return (dispatch, getState) => { const { basicPriceAndTimeEstimatesLastRetrieved, basicPriceAndTimeEstimates, } = getState().gas const timeLastRetrieved = basicPriceAndTimeEstimatesLastRetrieved || loadLocalStorageData('BASIC_GAS_AND_TIME_API_ESTIMATES_LAST_RETRIEVED') || 0 dispatch(basicGasEstimatesLoadingStarted()) const promiseToFetch = Date.now() - timeLastRetrieved > 75000 ? fetch('https://ethgasstation.info/json/ethgasAPI.json', { 'headers': {}, 'referrer': 'http://ethgasstation.info/json/', 'referrerPolicy': 'no-referrer-when-downgrade', 'body': null, 'method': 'GET', 'mode': 'cors'} ) .then(r => r.json()) .then(({ average: averageTimes10, avgWait, block_time: blockTime, blockNum, fast: fastTimes10, fastest: fastestTimes10, fastestWait, fastWait, safeLow: safeLowTimes10, safeLowWait, speed, }) => { const [average, fast, fastest, safeLow] = [ averageTimes10, fastTimes10, fastestTimes10, safeLowTimes10, ].map(price => (new BigNumber(price)).div(10).toNumber()) const basicEstimates = { average, avgWait, blockTime, blockNum, fast, fastest, fastestWait, fastWait, safeLow, safeLowWait, speed, } const timeRetrieved = Date.now() dispatch(setBasicApiEstimatesLastRetrieved(timeRetrieved)) saveLocalStorageData(timeRetrieved, 'BASIC_GAS_AND_TIME_API_ESTIMATES_LAST_RETRIEVED') saveLocalStorageData(basicEstimates, 'BASIC_GAS_AND_TIME_API_ESTIMATES') return basicEstimates }) : Promise.resolve(basicPriceAndTimeEstimates.length ? basicPriceAndTimeEstimates : loadLocalStorageData('BASIC_GAS_AND_TIME_API_ESTIMATES') ) return promiseToFetch.then(basicEstimates => { dispatch(setBasicGasEstimateData(basicEstimates)) dispatch(basicGasEstimatesLoadingFinished()) return basicEstimates }) } } function extrapolateY ({ higherY, lowerY, higherX, lowerX, xForExtrapolation }) { higherY = new BigNumber(higherY, 10) lowerY = new BigNumber(lowerY, 10) higherX = new BigNumber(higherX, 10) lowerX = new BigNumber(lowerX, 10) xForExtrapolation = new BigNumber(xForExtrapolation, 10) const slope = (higherY.minus(lowerY)).div(higherX.minus(lowerX)) const newTimeEstimate = slope.times(higherX.minus(xForExtrapolation)).minus(higherY).negated() return Number(newTimeEstimate.toPrecision(10)) } function getRandomArbitrary (min, max) { min = new BigNumber(min, 10) max = new BigNumber(max, 10) const random = new BigNumber(String(Math.random()), 10) return new BigNumber(random.times(max.minus(min)).plus(min)).toPrecision(10) } function calcMedian (list) { const medianPos = (Math.floor(list.length / 2) + Math.ceil(list.length / 2)) / 2 return medianPos === Math.floor(medianPos) ? (list[medianPos - 1] + list[medianPos]) / 2 : list[Math.floor(medianPos)] } function quartiles (data) { const lowerHalf = data.slice(0, Math.floor(data.length / 2)) const upperHalf = data.slice(Math.floor(data.length / 2) + (data.length % 2 === 0 ? 0 : 1)) const median = calcMedian(data) const lowerQuartile = calcMedian(lowerHalf) const upperQuartile = calcMedian(upperHalf) return { median, lowerQuartile, upperQuartile, } } function inliersByIQR (data, prop) { const { lowerQuartile, upperQuartile } = quartiles(data.map(d => prop ? d[prop] : d)) const IQR = upperQuartile - lowerQuartile const lowerBound = lowerQuartile - 1.5 * IQR const upperBound = upperQuartile + 1.5 * IQR return data.filter(d => { const value = prop ? d[prop] : d return value >= lowerBound && value <= upperBound }) } export function fetchGasEstimates (blockTime) { return (dispatch, getState) => { const { priceAndTimeEstimatesLastRetrieved, priceAndTimeEstimates, } = getState().gas const timeLastRetrieved = priceAndTimeEstimatesLastRetrieved || loadLocalStorageData('GAS_API_ESTIMATES_LAST_RETRIEVED') || 0 dispatch(gasEstimatesLoadingStarted()) const promiseToFetch = Date.now() - timeLastRetrieved > 75000 ? fetch('https://ethgasstation.info/json/predictTable.json', { 'headers': {}, 'referrer': 'http://ethgasstation.info/json/', 'referrerPolicy': 'no-referrer-when-downgrade', 'body': null, 'method': 'GET', 'mode': 'cors'} ) .then(r => r.json()) .then(r => { const estimatedPricesAndTimes = r.map(({ expectedTime, expectedWait, gasprice }) => ({ expectedTime, expectedWait, gasprice })) const estimatedTimeWithUniquePrices = uniqBy(({ expectedTime }) => expectedTime, estimatedPricesAndTimes) const withSupplementalTimeEstimates = flatten(estimatedTimeWithUniquePrices.map(({ expectedWait, gasprice }, i, arr) => { const next = arr[i + 1] if (!next) { return [{ expectedWait, gasprice }] } else { const supplementalPrice = getRandomArbitrary(gasprice, next.gasprice) const supplementalTime = extrapolateY({ higherY: next.expectedWait, lowerY: expectedWait, higherX: next.gasprice, lowerX: gasprice, xForExtrapolation: supplementalPrice, }) const supplementalPrice2 = getRandomArbitrary(supplementalPrice, next.gasprice) const supplementalTime2 = extrapolateY({ higherY: next.expectedWait, lowerY: supplementalTime, higherX: next.gasprice, lowerX: supplementalPrice, xForExtrapolation: supplementalPrice2, }) return [ { expectedWait, gasprice }, { expectedWait: supplementalTime, gasprice: supplementalPrice }, { expectedWait: supplementalTime2, gasprice: supplementalPrice2 }, ] } })) const withOutliersRemoved = inliersByIQR(withSupplementalTimeEstimates.slice(0).reverse(), 'expectedWait').reverse() const timeMappedToSeconds = withOutliersRemoved.map(({ expectedWait, gasprice }) => { const expectedTime = (new BigNumber(expectedWait)).times(Number(blockTime), 10).toNumber() return { expectedTime, gasprice: (new BigNumber(gasprice, 10).toNumber()), } }) const timeRetrieved = Date.now() dispatch(setApiEstimatesLastRetrieved(timeRetrieved)) saveLocalStorageData(timeRetrieved, 'GAS_API_ESTIMATES_LAST_RETRIEVED') saveLocalStorageData(timeMappedToSeconds, 'GAS_API_ESTIMATES') return timeMappedToSeconds }) : Promise.resolve(priceAndTimeEstimates.length ? priceAndTimeEstimates : loadLocalStorageData('GAS_API_ESTIMATES') ) return promiseToFetch.then(estimates => { dispatch(setPricesAndTimeEstimates(estimates)) dispatch(gasEstimatesLoadingFinished()) }) } } export function setBasicGasEstimateData (basicGasEstimateData) { return { type: SET_BASIC_GAS_ESTIMATE_DATA, value: basicGasEstimateData, } } export function setPricesAndTimeEstimates (estimatedPricesAndTimes) { return { type: SET_PRICE_AND_TIME_ESTIMATES, value: estimatedPricesAndTimes, } } export function setCustomGasPrice (newPrice) { return { type: SET_CUSTOM_GAS_PRICE, value: newPrice, } } export function setCustomGasLimit (newLimit) { return { type: SET_CUSTOM_GAS_LIMIT, value: newLimit, } } export function setCustomGasTotal (newTotal) { return { type: SET_CUSTOM_GAS_TOTAL, value: newTotal, } } export function setCustomGasErrors (newErrors) { return { type: SET_CUSTOM_GAS_ERRORS, value: newErrors, } } export function setApiEstimatesLastRetrieved (retrievalTime) { return { type: SET_API_ESTIMATES_LAST_RETRIEVED, value: retrievalTime, } } export function setBasicApiEstimatesLastRetrieved (retrievalTime) { return { type: SET_BASIC_API_ESTIMATES_LAST_RETRIEVED, value: retrievalTime, } } export function resetCustomGasState () { return { type: RESET_CUSTOM_GAS_STATE } } export function resetCustomData () { return { type: RESET_CUSTOM_DATA } }