const ObservableStore = require('obs-store')
const normalizeAddress = require('eth-sig-util').normalize
const { isValidAddress } = require('ethereumjs-util')
const extend = require('xtend')
class PreferencesController {
/**
*
* @typedef {Object} PreferencesController
* @param {object} opts Overrides the defaults for the initial state of this.store
* @property {object} store The stored object containing a users preferences, stored in local storage
* @property {array} store.frequentRpcList A list of custom rpcs to provide the user
* @property {string} store.currentAccountTab Indicates the selected tab in the ui
* @property {array} store.tokens The tokens the user wants display in their token lists
* @property {object} store.accountTokens The tokens stored per account and then per network type
* @property {object} store.assetImages Contains assets objects related to assets added
* @property {boolean} store.useBlockie The users preference for blockie identicons within the UI
* @property {object} store.featureFlags A key-boolean map, where keys refer to features and booleans to whether the
* user wishes to see that feature
* @property {string} store.currentLocale The preferred language locale key
* @property {string} store.selectedAddress A hex string that matches the currently selected address in the app
*
*/
constructor (opts = {}) {
const initState = extend({
frequentRpcList: [],
currentAccountTab: 'history',
accountTokens: {},
assetImages: {},
tokens: [],
suggestedTokens: {},
useBlockie: false,
featureFlags: {},
currentLocale: opts.initLangCode,
identities: {},
lostIdentities: {},
seedWords: null,
forgottenPassword: false,
}, opts.initState)
this.diagnostics = opts.diagnostics
this.network = opts.network
this.store = new ObservableStore(initState)
this.showWatchAssetUi = opts.showWatchAssetUi
this._subscribeProviderType()
}
// PUBLIC METHODS
/**
* Sets the {@code forgottenPassword} state property
* @param {boolean} forgottenPassword whether or not the user has forgotten their password
*/
setPasswordForgotten (forgottenPassword) {
this.store.updateState({ forgottenPassword })
}
/**
* Sets the {@code seedWords} seed words
* @param {string|null} seedWords the seed words
*/
setSeedWords (seedWords) {
this.store.updateState({ seedWords })
}
/**
* Setter for the `useBlockie` property
*
* @param {boolean} val Whether or not the user prefers blockie indicators
*
*/
setUseBlockie (val) {
this.store.updateState({ useBlockie: val })
}
getSuggestedTokens () {
return this.store.getState().suggestedTokens
}
getAssetImages () {
return this.store.getState().assetImages
}
addSuggestedERC20Asset (tokenOpts) {
this._validateERC20AssetParams(tokenOpts)
const suggested = this.getSuggestedTokens()
const { rawAddress, symbol, decimals, image } = tokenOpts
const address = normalizeAddress(rawAddress)
const newEntry = { address, symbol, decimals, image }
suggested[address] = newEntry
this.store.updateState({ suggestedTokens: suggested })
}
/**
* RPC engine middleware for requesting new asset added
*
* @param req
* @param res
* @param {Function} - next
* @param {Function} - end
*/
async requestWatchAsset (req, res, next, end) {
if (req.method === 'metamask_watchAsset') {
const { type, options } = req.params
switch (type) {
case 'ERC20':
const result = await this._handleWatchAssetERC20(options)
if (result instanceof Error) {
end(result)
} else {
res.result = result
end()
}
break
default:
end(new Error(`Asset of type ${type} not supported`))
}
} else {
next()
}
}
/**
* Getter for the `useBlockie` property
*
* @returns {boolean} this.store.useBlockie
*
*/
getUseBlockie () {
return this.store.getState().useBlockie
}
/**
* Setter for the `currentLocale` property
*
* @param {string} key he preferred language locale key
*
*/
setCurrentLocale (key) {
this.store.updateState({ currentLocale: key })
}
/**
* Updates identities to only include specified addresses. Removes identities
* not included in addresses array
*
* @param {string[]} addresses An array of hex addresses
*
*/
setAddresses (addresses) {
const oldIdentities = this.store.getState().identities
const oldAccountTokens = this.store.getState().accountTokens
const identities = addresses.reduce((ids, address, index) => {
const oldId = oldIdentities[address] || {}
ids[address] = {name: `Account ${index + 1}`, address, ...oldId}
return ids
}, {})
const accountTokens = addresses.reduce((tokens, address) => {
const oldTokens = oldAccountTokens[address] || {}
tokens[address] = oldTokens
return tokens
}, {})
this.store.updateState({ identities, accountTokens })
}
/**
* Removes an address from state
*
* @param {string} address A hex address
* @returns {string} the address that was removed
*/
removeAddress (address) {
const identities = this.store.getState().identities
const accountTokens = this.store.getState().accountTokens
if (!identities[address]) {
throw new Error(`${address} can't be deleted cause it was not found`)
}
delete identities[address]
delete accountTokens[address]
this.store.updateState({ identities, accountTokens })
// If the selected account is no longer valid,
// select an arbitrary other account:
if (address === this.getSelectedAddress()) {
const selected = Object.keys(identities)[0]
this.setSelectedAddress(selected)
}
return address
}
/**
* Adds addresses to the identities object without removing identities
*
* @param {string[]} addresses An array of hex addresses
*
*/
addAddresses (addresses) {
const identities = this.store.getState().identities
const accountTokens = this.store.getState().accountTokens
addresses.forEach((address) => {
// skip if already exists
if (identities[address]) return
// add missing identity
const identityCount = Object.keys(identities).length
accountTokens[address] = {}
identities[address] = { name: `Account ${identityCount + 1}`, address }
})
this.store.updateState({ identities, accountTokens })
}
/*
* Synchronizes identity entries with known accounts.
* Removes any unknown identities, and returns the resulting selected address.
*
* @param {Array<string>} addresses known to the vault.
* @returns {Promise<string>} selectedAddress the selected address.
*/
syncAddresses (addresses) {
const { identities, lostIdentities } = this.store.getState()
const newlyLost = {}
Object.keys(identities).forEach((identity) => {
if (!addresses.includes(identity)) {
newlyLost[identity] = identities[identity]
delete identities[identity]
}
})
// Identities are no longer present.
if (Object.keys(newlyLost).length > 0) {
// Notify our servers:
if (this.diagnostics) this.diagnostics.reportOrphans(newlyLost)
// store lost accounts
for (const key in newlyLost) {
lostIdentities[key] = newlyLost[key]
}
}
this.store.updateState({ identities, lostIdentities })
this.addAddresses(addresses)
// If the selected account is no longer valid,
// select an arbitrary other account:
let selected = this.getSelectedAddress()
if (!addresses.includes(selected)) {
selected = addresses[0]
this.setSelectedAddress(selected)
}
return selected
}
removeSuggestedTokens () {
return new Promise((resolve, reject) => {
this.store.updateState({ suggestedTokens: {} })
resolve({})
})
}
/**
* Setter for the `selectedAddress` property
*
* @param {string} _address A new hex address for an account
* @returns {Promise<void>} Promise resolves with tokens
*
*/
setSelectedAddress (_address) {
const address = normalizeAddress(_address)
this._updateTokens(address)
this.store.updateState({ selectedAddress: address })
const tokens = this.store.getState().tokens
return Promise.resolve(tokens)
}
/**
* Getter for the `selectedAddress` property
*
* @returns {string} The hex address for the currently selected account
*
*/
getSelectedAddress () {
return this.store.getState().selectedAddress
}
/**
* Contains data about tokens users add to their account.
* @typedef {Object} AddedToken
* @property {string} address - The hex address for the token contract. Will be all lower cased and hex-prefixed.
* @property {string} symbol - The symbol of the token, usually 3 or 4 capitalized letters
* {@link https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20.md#symbol}
* @property {boolean} decimals - The number of decimals the token uses.
* {@link https://github.com/ethereum/EIPs/blob/master/EIPS/eip-20.md#decimals}
*/
/**
* Adds a new token to the token array, or updates the token if passed an address that already exists.
* Modifies the existing tokens array from the store. All objects in the tokens array array AddedToken objects.
* @see AddedToken {@link AddedToken}
*
* @param {string} rawAddress Hex address of the token contract. May or may not be a checksum address.
* @param {string} symbol The symbol of the token
* @param {number} decimals The number of decimals the token uses.
* @returns {Promise<array>} Promises the new array of AddedToken objects.
*
*/
async addToken (rawAddress, symbol, decimals, image) {
const address = normalizeAddress(rawAddress)
const newEntry = { address, symbol, decimals }
const tokens = this.store.getState().tokens
const assetImages = this.getAssetImages()
const previousEntry = tokens.find((token, index) => {
return token.address === address
})
const previousIndex = tokens.indexOf(previousEntry)
if (previousEntry) {
tokens[previousIndex] = newEntry
} else {
tokens.push(newEntry)
}
assetImages[address] = image
this._updateAccountTokens(tokens, assetImages)
return Promise.resolve(tokens)
}
/**
* Removes a specified token from the tokens array.
*
* @param {string} rawAddress Hex address of the token contract to remove.
* @returns {Promise<array>} The new array of AddedToken objects
*
*/
removeToken (rawAddress) {
const tokens = this.store.getState().tokens
const assetImages = this.getAssetImages()
const updatedTokens = tokens.filter(token => token.address !== rawAddress)
delete assetImages[rawAddress]
this._updateAccountTokens(updatedTokens, assetImages)
return Promise.resolve(updatedTokens)
}
/**
* A getter for the `tokens` property
*
* @returns {array} The current array of AddedToken objects
*
*/
getTokens () {
return this.store.getState().tokens
}
/**
* Sets a custom label for an account
* @param {string} account the account to set a label for
* @param {string} label the custom label for the account
* @return {Promise<string>}
*/
setAccountLabel (account, label) {
if (!account) throw new Error('setAccountLabel requires a valid address, got ' + String(account))
const address = normalizeAddress(account)
const {identities} = this.store.getState()
identities[address] = identities[address] || {}
identities[address].name = label
this.store.updateState({ identities })
return Promise.resolve(label)
}
/**
* Gets an updated rpc list from this.addToFrequentRpcList() and sets the `frequentRpcList` to this update list.
*
* @param {string} _url The the new rpc url to add to the updated list
* @returns {Promise<void>} Promise resolves with undefined
*
*/
updateFrequentRpcList (_url) {
return this.addToFrequentRpcList(_url)
.then((rpcList) => {
this.store.updateState({ frequentRpcList: rpcList })
return Promise.resolve()
})
}
/**
* Setter for the `currentAccountTab` property
*
* @param {string} currentAccountTab Specifies the new tab to be marked as current
* @returns {Promise<void>} Promise resolves with undefined
*
*/
setCurrentAccountTab (currentAccountTab) {
return new Promise((resolve, reject) => {
this.store.updateState({ currentAccountTab })
resolve()
})
}
/**
* Returns an updated rpcList based on the passed url and the current list.
* The returned list will have a max length of 3. If the _url currently exists it the list, it will be moved to the
* end of the list. The current list is modified and returned as a promise.
*
* @param {string} _url The rpc url to add to the frequentRpcList.
* @returns {Promise<array>} The updated frequentRpcList.
*
*/
addToFrequentRpcList (_url) {
const rpcList = this.getFrequentRpcList()
const index = rpcList.findIndex((element) => { return element === _url })
if (index !== -1) {
rpcList.splice(index, 1)
}
if (_url !== 'http://localhost:8545') {
rpcList.push(_url)
}
if (rpcList.length > 3) {
rpcList.shift()
}
return Promise.resolve(rpcList)
}
/**
* Getter for the `frequentRpcList` property.
*
* @returns {array<string>} An array of one or two rpc urls.
*
*/
getFrequentRpcList () {
return this.store.getState().frequentRpcList
}
/**
* Updates the `featureFlags` property, which is an object. One property within that object will be set to a boolean.
*
* @param {string} feature A key that corresponds to a UI feature.
* @param {boolean} activated Indicates whether or not the UI feature should be displayed
* @returns {Promise<object>} Promises a new object; the updated featureFlags object.
*
*/
setFeatureFlag (feature, activated) {
const currentFeatureFlags = this.store.getState().featureFlags
const updatedFeatureFlags = {
...currentFeatureFlags,
[feature]: activated,
}
this.store.updateState({ featureFlags: updatedFeatureFlags })
return Promise.resolve(updatedFeatureFlags)
}
/**
* A getter for the `featureFlags` property
*
* @returns {object} A key-boolean map, where keys refer to features and booleans to whether the
* user wishes to see that feature
*
*/
getFeatureFlags () {
return this.store.getState().featureFlags
}
//
// PRIVATE METHODS
//
/**
* Subscription to network provider type.
*
*
*/
_subscribeProviderType () {
this.network.providerStore.subscribe(() => {
const { tokens } = this._getTokenRelatedStates()
this.store.updateState({ tokens })
})
}
/**
* Updates `accountTokens` and `tokens` of current account and network according to it.
*
* @param {array} tokens Array of tokens to be updated.
*
*/
_updateAccountTokens (tokens, assetImages) {
const { accountTokens, providerType, selectedAddress } = this._getTokenRelatedStates()
accountTokens[selectedAddress][providerType] = tokens
this.store.updateState({ accountTokens, tokens, assetImages })
}
/**
* Updates `tokens` of current account and network.
*
* @param {string} selectedAddress Account address to be updated with.
*
*/
_updateTokens (selectedAddress) {
const { tokens } = this._getTokenRelatedStates(selectedAddress)
this.store.updateState({ tokens })
}
/**
* A getter for `tokens` and `accountTokens` related states.
*
* @param {string} selectedAddress A new hex address for an account
* @returns {Object.<array, object, string, string>} States to interact with tokens in `accountTokens`
*
*/
_getTokenRelatedStates (selectedAddress) {
const accountTokens = this.store.getState().accountTokens
if (!selectedAddress) selectedAddress = this.store.getState().selectedAddress
const providerType = this.network.providerStore.getState().type
if (!(selectedAddress in accountTokens)) accountTokens[selectedAddress] = {}
if (!(providerType in accountTokens[selectedAddress])) accountTokens[selectedAddress][providerType] = []
const tokens = accountTokens[selectedAddress][providerType]
return { tokens, accountTokens, providerType, selectedAddress }
}
/**
* Handle the suggestion of an ERC20 asset through `watchAsset`
* *
* @param {Promise} promise Promise according to addition of ERC20 token
*
*/
async _handleWatchAssetERC20 (options) {
const { address, symbol, decimals, image } = options
const rawAddress = address
try {
this._validateERC20AssetParams({ rawAddress, symbol, decimals })
} catch (err) {
return err
}
const tokenOpts = { rawAddress, decimals, symbol, image }
this.addSuggestedERC20Asset(tokenOpts)
return this.showWatchAssetUi().then(() => {
const tokenAddresses = this.getTokens().filter(token => token.address === normalizeAddress(rawAddress))
return tokenAddresses.length > 0
})
}
/**
* Validates that the passed options for suggested token have all required properties.
*
* @param {Object} opts The options object to validate
* @throws {string} Throw a custom error indicating that address, symbol and/or decimals
* doesn't fulfill requirements
*
*/
_validateERC20AssetParams (opts) {
const { rawAddress, symbol, decimals } = opts
if (!rawAddress || !symbol || !decimals) throw new Error(`Cannot suggest token without address, symbol, and decimals`)
if (!(symbol.length < 6)) throw new Error(`Invalid symbol ${symbol} more than five characters`)
const numDecimals = parseInt(decimals, 10)
if (isNaN(numDecimals) || numDecimals > 36 || numDecimals < 0) {
throw new Error(`Invalid decimals ${decimals} must be at least 0, and not over 36`)
}
if (!isValidAddress(rawAddress)) throw new Error(`Invalid address ${rawAddress}`)
}
}
module.exports = PreferencesController