feat: enable token transactions

Fixes #788.
Fixes #853.
Fixes #856.

refactor: gas estimation and transaction sends have been abstracted to  allow calling `estimateGas`, `send`, and `call` on the contract method (similar to the web3 API).

Moved sticker pack gas estimation and purchase tx over to the new API

*Sticker purchase:*
 - gas estimate is done using new API and debounced using a timer

*Wallet send transaction:*
 - tokens can now be sent
 - gas is estimated correctly for a token tx, and debounced using a timer

***NOTE***
1. If attempting to send tokens on testnet, you must use a custom token as the token addresses in the pre-built list are for mainnet and will not work on testnet.
2. The new API should support all existing gas estimates, send txs, and calls. The loading of sticker pack data, balance, count, purchased sticker packs, etc, can be moved over to the new API. Almost all of the `eth_sendTransaction`, `eth_gasEstimate`, and `eth_call` could be move over as well (that's the idea at least).

src/app/chat/view.nim

@@ -1,4 +1,4 @@
-import NimQml, Tables, json, sequtils, chronicles, times, re, sugar, strutils, os, strformat
+import NimQml, Tables, json, sequtils, chronicles, times, re, sugar, strutils, os
 import ../../status/status
 import ../../status/mailservers
 import ../../status/stickers
@@ -105,17 +105,18 @@ QtObject:
   QtProperty[QVariant] stickerMarketAddress:
     read = getStickerMarketAddress
 
-  proc getStickerBuyPackGasEstimate*(self: ChatsView, packId: int, address: string, price: string): string {.slot.} =
+  proc buyPackGasEstimate*(self: ChatsView, packId: int, address: string, price: string): int {.slot.} =
     try:
-      result = self.status.stickers.buyPackGasEstimate(packId, address, price)
+      result = self.status.stickers.estimateGas(packId, address, price)
     except:
-      result = "400000"
+      result = 325000
 
   proc buyStickerPack*(self: ChatsView, packId: int, address: string, price: string, gas: string, gasPrice: string, password: string): string {.slot.} =
     try:
-      result = $(%self.status.stickers.buyStickerPack(packId, address, price, gas, gasPrice, password))
+      let response = self.status.stickers.buyPack(packId, address, price, gas, gasPrice, password)
+      result = $(%* { "result": %response })
     except RpcException as e:
-      result = fmt"""{{ "error": {{ "message": "{e.msg}" }} }}"""
+      result = $(%* { "error": %* { "message": %e.msg }})
 
   proc obtainAvailableStickerPacks*(self: ChatsView) =
     spawnAndSend(self, "setAvailableStickerPacks") do:

src/app/wallet/view.nim

@@ -1,6 +1,7 @@
 import NimQml, Tables, strformat, strutils, chronicles, json, std/wrapnils, parseUtils, stint, tables
 import ../../status/[status, wallet, threads]
 import ../../status/wallet/collectibles as status_collectibles
+import ../../status/libstatus/accounts/constants
 import ../../status/libstatus/wallet as status_wallet
 import ../../status/libstatus/tokens
 import ../../status/libstatus/types
@@ -91,7 +92,7 @@ QtObject:
     read = getSigningPhrase
     notify = signingPhraseChanged
 
-  proc getStatusTokenSymbol*(self: WalletView): string {.slot.} = self.status.wallet.getStatusTokenSymbol
+  proc getStatusToken*(self: WalletView): string {.slot.} = self.status.wallet.getStatusToken
 
   proc setCurrentAssetList*(self: WalletView, assetList: seq[Asset])
 
@@ -263,11 +264,27 @@ QtObject:
     read = getAccountList
     notify = accountListChanged
   
+  proc estimateGas*(self: WalletView, from_addr: string, to: string, assetAddress: string, value: string): string {.slot.} =
+    try:
+      var response: int
+      if assetAddress != ZERO_ADDRESS and not assetAddress.isEmptyOrWhitespace:
+        response = self.status.wallet.estimateTokenGas(from_addr, to, assetAddress, value)
+      else:
+        response = self.status.wallet.estimateGas(from_addr, to, value)
+      result = $(%* { "result": %response })
+    except RpcException as e:
+      result = $(%* { "error": %* { "message": %e.msg }})
+
   proc sendTransaction*(self: WalletView, from_addr: string, to: string, assetAddress: string, value: string, gas: string, gasPrice: string, password: string): string {.slot.} =
     try:
-      result = $(%self.status.wallet.sendTransaction(from_addr, to, assetAddress, value, gas, gasPrice, password))
+      var response = ""
+      if assetAddress != ZERO_ADDRESS and not assetAddress.isEmptyOrWhitespace:
+        response = self.status.wallet.sendTokenTransaction(from_addr, to, assetAddress, value, gas, gasPrice, password)
+      else:
+        response = self.status.wallet.sendTransaction(from_addr, to, value, gas, gasPrice, password)
+      result = $(%* { "result": %response })
     except RpcException as e:
-      result = fmt"""{{ "error": {{ "message": "{e.msg}" }} }}"""
+      result = $(%* { "error": %* { "message": %e.msg }})
 
   proc getDefaultAccount*(self: WalletView): string {.slot.} =
     self.currentAccount.address

src/status/chat.nim

@@ -1,11 +1,10 @@
-import eventemitter, json, strutils, sequtils, tables, chronicles, sugar, times
-import libstatus/contracts as status_contracts
+import eventemitter, json, strutils, sequtils, tables, chronicles, times
 import libstatus/chat as status_chat
 import libstatus/mailservers as status_mailservers
 import libstatus/chatCommands as status_chat_commands
 import libstatus/accounts/constants as constants
 import libstatus/types
-import mailservers, stickers
+import stickers
 import profile/profile
 import chat/[chat, message]
 import signals/messages

src/status/ens.nim

@@ -12,7 +12,7 @@ import stew/byteutils
 import unicode
 import algorithm
 import eth/common/eth_types, stew/byteutils
-import libstatus/contracts
+import libstatus/eth/contracts
 const domain* = ".stateofus.eth"
 
 proc userName*(ensName: string, removeSuffix: bool = false): string =

src/status/libstatus/coder.nim

@@ -194,3 +194,7 @@ func decode*[T](input: string, to: seq[T]): seq[T] =
 func decode*[T; I: static int](input: string, to: array[0..I, T]): array[0..I, T] =
   for i in 0..I:
     result[i] = input[i*64 .. (i+1)*64].decode(T)
+
+func decodeContractResponse*[T](input: string): T =
+  result = T()
+  discard decode(input.strip0xPrefix, 0, result)

src/status/libstatus/eth/contracts.nim

@@ -1,15 +1,17 @@
-import sequtils, strformat, sugar, macros, tables, strutils
-import eth/common/eth_types, stew/byteutils, nimcrypto
+import
+  sequtils, sugar, macros, tables, strutils
+
+import
+  eth/common/eth_types, stew/byteutils, nimcrypto
 from eth/common/utils import parseAddress
-import ./types, ./settings, ./coder
+
+import
+  ../types, ../settings, ../coder, transactions, methods
 
 export
   GetPackData, PackData, BuyToken, ApproveAndCall, Transfer, BalanceOf, Register, SetPubkey,
-  TokenOfOwnerByIndex, TokenPackId, TokenUri, FixedBytes, DynamicBytes, toHex, fromHex
-
-type Method* = object
-  name*: string
-  signature*: string
+  TokenOfOwnerByIndex, TokenPackId, TokenUri, FixedBytes, DynamicBytes, toHex, fromHex,
+  decodeContractResponse, encodeAbi, estimateGas, send, call
 
 type Contract* = ref object
   name*: string
@@ -121,32 +123,3 @@ proc getContract(network: Network, name: string): Contract =
 proc getContract*(name: string): Contract =
   let network = settings.getCurrentNetwork()
   getContract(network, name)
-
-proc encodeMethod(self: Method): string =
-  ($nimcrypto.keccak256.digest(self.signature))[0..<8].toLower
-
-proc encodeAbi*(self: Method, obj: object = RootObj()): string =
-  result = "0x" & self.encodeMethod()
-
-  # .fields is an iterator, and there's no way to get a count of an iterator
-  # in nim, so we have to loop and increment a counter
-  var fieldCount = 0
-  for i in obj.fields:
-    fieldCount += 1
-  var
-    offset = 32*fieldCount
-    data = ""
-
-  for field in obj.fields:
-    let encoded = encode(field)
-    if encoded.dynamic:
-      result &= offset.toHex(64).toLower
-      data &= encoded.data
-      offset += encoded.data.len
-    else:
-      result &= encoded.data
-  result &= data
-
-func decodeContractResponse*[T](input: string): T =
-  result = T()
-  discard decode(input.strip0xPrefix, 0, result)

src/status/libstatus/eth/eth.nim

@@ -0,0 +1,10 @@
+import
+  transactions, ../types
+
+proc sendTransaction*(tx: var EthSend, password: string): string =
+  let response = transactions.sendTransaction(tx, password)
+  result = response.result
+
+proc estimateGas*(tx: var EthSend): string =
+  let response = transactions.estimateGas(tx)
+  result = response.result

src/status/libstatus/eth/methods.nim

@@ -0,0 +1,55 @@
+import
+  strutils, options
+
+import
+  nimcrypto, eth/common/eth_types
+
+import 
+  ../coder, eth, transactions, ../types
+
+export sendTransaction
+
+type Method* = object
+  name*: string
+  signature*: string
+
+proc encodeMethod(self: Method): string =
+  ($nimcrypto.keccak256.digest(self.signature))[0..<8].toLower
+
+proc encodeAbi*(self: Method, obj: object = RootObj()): string =
+  result = "0x" & self.encodeMethod()
+
+  # .fields is an iterator, and there's no way to get a count of an iterator
+  # in nim, so we have to loop and increment a counter
+  var fieldCount = 0
+  for i in obj.fields:
+    fieldCount += 1
+  var
+    offset = 32*fieldCount
+    data = ""
+
+  for field in obj.fields:
+    let encoded = encode(field)
+    if encoded.dynamic:
+      result &= offset.toHex(64).toLower
+      data &= encoded.data
+      offset += encoded.data.len
+    else:
+      result &= encoded.data
+  result &= data
+
+proc estimateGas*(self: Method, tx: var EthSend, methodDescriptor: object): string =
+  tx.data = self.encodeAbi(methodDescriptor)
+  let response = transactions.estimateGas(tx)
+  result = response.result # gas estimate in hex
+
+proc send*(self: Method, tx: var EthSend, methodDescriptor: object, password: string): string =
+  tx.data = self.encodeAbi(methodDescriptor)
+  result = eth.sendTransaction(tx, password)
+  # result = coder.decodeContractResponse[string](response.result)
+  # result = response.result
+
+proc call*[T](self: Method, tx: var EthSend, methodDescriptor: object): T =
+  tx.data = self.encodeAbi(methodDescriptor)
+  let response = transactions.call(tx)
+  result = coder.decodeContractResponse[T](response.result)

src/status/libstatus/eth/transactions.nim

@@ -0,0 +1,30 @@
+import
+  json
+
+import
+  json_serialization, chronicles
+
+import
+  ../core, ../types
+
+proc estimateGas*(tx: EthSend): RpcResponse =
+  let response = core.callPrivateRPC("eth_estimateGas", %*[%tx])
+  result = Json.decode(response, RpcResponse)
+  if not result.error.isNil:
+    raise newException(RpcException, "Error getting gas estimate: " & result.error.message)
+
+  trace "Gas estimated succesfully", estimate=result.result
+
+proc sendTransaction*(tx: EthSend, password: string): RpcResponse =
+  let responseStr = core.sendTransaction($(%tx), password)
+  result = Json.decode(responseStr, RpcResponse)
+  if not result.error.isNil:
+    raise newException(RpcException, "Error sending transaction: " & result.error.message)
+
+  trace "Transaction sent succesfully", hash=result.result
+
+proc call*(tx: EthSend): RpcResponse =
+  let responseStr = core.callPrivateRPC("eth_call", %*[%tx])
+  result = Json.decode(responseStr, RpcResponse)
+  if not result.error.isNil:
+    raise newException(RpcException, "Error calling method: " & result.error.message)

src/status/libstatus/stickers.nim

@@ -1,4 +1,4 @@
-import ./core as status, ./types, ./contracts, ./settings, ./edn_helpers
+import ./core as status, ./types, ./eth/contracts, ./settings, ./edn_helpers
 import
   json, json_serialization, tables, chronicles, strutils, sequtils, httpclient,
   stint, libp2p/[multihash, multicodec, cid], eth/common/eth_types
@@ -124,43 +124,6 @@ proc getPackData*(id: Stuint[256]): StickerPack =
     result.id = truncate(id, int)
     result.price = packData.price
 
-proc buyPackPayload(packId: Stuint[256], address: EthAddress, price: Stuint[256]): JsonNode =
-  let
-    stickerMktContract = contracts.getContract("sticker-market")
-    sntContract = contracts.getContract("snt")
-    buyToken = BuyToken(packId: packId, address: address, price: price)
-    buyTxAbiEncoded = stickerMktContract.methods["buyToken"].encodeAbi(buyToken)
-  let
-    approveAndCallObj = ApproveAndCall(to: stickerMktContract.address, value: price, data: DynamicBytes[100].fromHex(buyTxAbiEncoded))
-    approveAndCallAbiEncoded = sntContract.methods["approveAndCall"].encodeAbi(approveAndCallObj)
-  result = %* {
-    "from": $address,
-    "to": $sntContract.address,
-    "data": approveAndCallAbiEncoded
-  }
-
-proc buyPackGasEstimate*(packId: Stuint[256], address: EthAddress, price: Stuint[256]): string =
-  # TODO: pass in an EthSend object instead
-  let payload = buyPackPayload(packId, address, price)  
-  let responseStr = status.callPrivateRPC("eth_estimateGas", %*[payload])
-  let response = Json.decode(responseStr, RpcResponse)
-  if not response.error.isNil:
-    raise newException(RpcException, "Error getting stickers buy pack gas estimate: " & response.error.message)
-  result = response.result # should be a tx receipt
-
-# Buys a sticker pack for user
-# See https://notes.status.im/Q-sQmQbpTOOWCQcYiXtf5g#Buy-a-Sticker-Pack for more
-# details
-proc buyPack*(packId: Stuint[256], address: EthAddress, price: Stuint[256], gas: uint64, gasPrice: int, password: string): RpcResponse =
-  # TODO: pass in an EthSend object instead
-  let payload = buyPackPayload(packId, address, price)
-  payload{"gas"} = %gas.encodeQuantity
-  payload{"gasPrice"} = %("0x" & gasPrice.toHex.stripLeadingZeros)
-  let responseStr = status.sendTransaction($payload, password)
-  result = Json.decode(responseStr, RpcResponse)
-  if not result.error.isNil:
-    raise newException(RpcException, "Error buying sticker pack: " & result.error.message)
-
 proc tokenOfOwnerByIndex*(address: EthAddress, idx: Stuint[256]): int =
   let
     contract = contracts.getContract("sticker-pack")

src/status/libstatus/tokens.nim

@@ -1,6 +1,6 @@
 import json, chronicles, strformat, stint, strutils
 import core, wallet
-import contracts
+import ./eth/contracts
 import eth/common/eth_types, eth/common/utils
 import json_serialization
 import settings

src/status/libstatus/utils.nim

@@ -1,5 +1,5 @@
-import json, random, strutils, strformat, tables, chronicles
-import stint, nim_status
+import json, random, strutils, strformat, tables, chronicles, unicode
+import stint
 from times import getTime, toUnix, nanosecond
 import accounts/signing_phrases
 
@@ -82,7 +82,7 @@ proc first*(jArray: JsonNode, fieldName, id: string): JsonNode =
   if jArray.kind != JArray:
     raise newException(ValueError, "Parameter 'jArray' is a " & $jArray.kind & ", but must be a JArray")
   for child in jArray.getElems:
-    if child{fieldName}.getStr == id:
+    if child{fieldName}.getStr.toLower == id.toLower:
       return child
 
 proc any*(jArray: JsonNode, fieldName, id: string): bool =
@@ -90,7 +90,7 @@ proc any*(jArray: JsonNode, fieldName, id: string): bool =
     return false
   result = false
   for child in jArray.getElems:
-    if child{fieldName}.getStr == id:
+    if child{fieldName}.getStr.toLower == id.toLower:
       return true
 
 proc isEmpty*(a: JsonNode): bool =

src/status/libstatus/wallet.nim

@@ -2,7 +2,7 @@ import json, json, options, json_serialization, stint, chronicles
 import core, types, utils, strutils, strformat
 from nim_status import validateMnemonic, startWallet
 import ../wallet/account
-import ./contracts as contractMethods
+import ./eth/contracts as contractMethods
 import eth/common/eth_types
 import ./types
 import ../signals/types as signal_types
@@ -62,14 +62,6 @@ proc getTransfersByAddress*(address: string): seq[types.Transaction] =
     let msg = getCurrentExceptionMsg()
     error "Failed getting wallet account transactions", msg
 
-proc sendTransaction*(tx: EthSend, password: string): RpcResponse =
-  let responseStr = core.sendTransaction($(%tx), password)
-  result = Json.decode(responseStr, RpcResponse)
-  if not result.error.isNil:
-    raise newException(RpcException, "Error sending transaction: " & result.error.message)
-
-  trace "Transaction sent succesfully", hash=result
-
 proc getBalance*(address: string): string =
   let payload = %* [address, "latest"]
   let response = parseJson(callPrivateRPC("eth_getBalance", payload))

src/status/stickers.nim

@@ -1,16 +1,14 @@
-import
+import # global deps
   tables, strutils, sequtils, sugar
 
-import
+import # project deps
   chronicles, eth/common/eth_types, eventemitter
-
 from eth/common/utils import parseAddress
 
-import
-  libstatus/types, libstatus/stickers as status_stickers,
-  libstatus/contracts as status_contracts
-
-from libstatus/utils as libstatus_utils import eth2Wei, gwei2Wei, toUInt64
+import # local deps
+  libstatus/types, libstatus/eth/contracts as status_contracts,
+  libstatus/stickers as status_stickers, transactions
+from libstatus/utils as libstatus_utils import eth2Wei
 
 logScope:
   topics = "stickers-model"
@@ -43,27 +41,53 @@ proc init*(self: StickersModel) =
     var evArgs = StickerArgs(e)
     self.addStickerToRecent(evArgs.sticker, evArgs.save)
 
-# TODO: Replace this with a more generalised way of estimating gas so can be used for token transfers
-proc buyPackGasEstimate*(self: StickersModel, packId: int, address: string, price: string): string =
+proc buildTransaction(self: StickersModel, packId: Uint256, address: EthAddress, price: Uint256, approveAndCall: var ApproveAndCall, sntContract: var Contract, gas = "", gasPrice = ""): EthSend =
+  sntContract = status_contracts.getContract("snt")
   let
-    priceTyped = eth2Wei(parseFloat(price), 18) # SNT
-    hexGas = status_stickers.buyPackGasEstimate(packId.u256, parseAddress(address), priceTyped)
-  result = $fromHex[int](hexGas)
+    stickerMktContract = status_contracts.getContract("sticker-market")
+    buyToken = BuyToken(packId: packId, address: address, price: price)
+    buyTxAbiEncoded = stickerMktContract.methods["buyToken"].encodeAbi(buyToken)
+  approveAndCall = ApproveAndCall(to: stickerMktContract.address, value: price, data: DynamicBytes[100].fromHex(buyTxAbiEncoded))
+  transactions.buildTokenTransaction(address, sntContract.address, gas, gasPrice)
+
+proc estimateGas*(self: StickersModel, packId: int, address: string, price: string): int =
+  var
+    approveAndCall: ApproveAndCall
+    sntContract = status_contracts.getContract("snt")
+    tx = self.buildTransaction(
+      packId.u256,
+      parseAddress(address),
+      eth2Wei(parseFloat(price), 18), # SNT
+      approveAndCall,
+      sntContract
+    )
+  try:
+    let response = sntContract.methods["approveAndCall"].estimateGas(tx, approveAndCall)
+    result = fromHex[int](response)
+  except RpcException as e:
+    raise
+
+proc buyPack*(self: StickersModel, packId: int, address, price, gas, gasPrice, password: string): string =
+  var
+    sntContract: Contract
+    approveAndCall: ApproveAndCall
+    tx = self.buildTransaction(
+      packId.u256,
+      parseAddress(address),
+      eth2Wei(parseFloat(price), 18), # SNT
+      approveAndCall,
+      sntContract,
+      gas,
+      gasPrice
+    )
+  try:
+    result = sntContract.methods["approveAndCall"].send(tx, approveAndCall, password)
+  except RpcException as e:
+    raise
 
 proc getStickerMarketAddress*(self: StickersModel): EthAddress =
   result = status_contracts.getContract("sticker-market").address
 
-proc buyStickerPack*(self: StickersModel, packId: int, address, price, gas, gasPrice, password: string): RpcResponse =
-  try:
-    let
-      addressTyped = parseAddress(address)
-      priceTyped = eth2Wei(parseFloat(price), 18) # SNT
-      gasTyped = cast[uint64](parseFloat(gas).toUInt64)
-      gasPriceTyped = gwei2Wei(parseFloat(gasPrice)).truncate(int)
-    result = status_stickers.buyPack(packId.u256, addressTyped, priceTyped, gasTyped, gasPriceTyped, password)
-  except RpcException as e:
-    raise
-
 proc getPurchasedStickerPacks*(self: StickersModel, address: EthAddress): seq[int] =
   if self.purchasedStickerPacks != @[]:
     return self.purchasedStickerPacks

src/status/transactions.nim

@@ -0,0 +1,23 @@
+import
+  options, strutils
+
+import
+  stint
+from eth/common/eth_types import EthAddress
+from eth/common/utils import parseAddress
+
+import
+  libstatus/types
+from libstatus/utils as status_utils import toUInt64, gwei2Wei
+
+proc buildTransaction*(source: EthAddress, value: Uint256, gas = "", gasPrice = ""): EthSend =
+  result = EthSend(
+    source: source,
+    value: value.some,
+    gas: (if gas.isEmptyOrWhitespace: Quantity.none else: Quantity(cast[uint64](parseFloat(gas).toUInt64)).some),
+    gasPrice: (if gasPrice.isEmptyOrWhitespace: int.none else: gwei2Wei(parseFloat(gasPrice)).truncate(int).some)
+  )
+
+proc buildTokenTransaction*(source, contractAddress: EthAddress, gas = "", gasPrice = ""): EthSend =
+  result = buildTransaction(source, 0.u256, gas, gasPrice)
+  result.to = contractAddress.some

src/status/wallet.nim

@@ -1,17 +1,17 @@
 import eventemitter, json, strformat, strutils, chronicles, sequtils, httpclient, tables
 import json_serialization, stint
 from eth/common/utils import parseAddress
+from eth/common/eth_types import EthAddress
 import libstatus/accounts as status_accounts
 import libstatus/tokens as status_tokens
 import libstatus/settings as status_settings
 import libstatus/wallet as status_wallet
 import libstatus/accounts/constants as constants
-import libstatus/contracts as contracts
-from libstatus/types import GeneratedAccount, DerivedAccount, Transaction, Setting, GasPricePrediction, EthSend, Quantity, `%`, StatusGoException, Network, RpcResponse, RpcException
+import libstatus/eth/[eth, contracts]
+from libstatus/types import GeneratedAccount, DerivedAccount, Transaction, Setting, GasPricePrediction, EthSend, Quantity, `%`, StatusGoException, Network, RpcResponse, RpcException, `$`
 from libstatus/utils as libstatus_utils import eth2Wei, gwei2Wei, first, toUInt64
-import wallet/balance_manager
-import wallet/account
-import wallet/collectibles
+import wallet/[balance_manager, account, collectibles]
+import transactions
 export account, collectibles
 export Transaction
 
@@ -50,34 +50,70 @@ proc initEvents*(self: WalletModel) =
 proc delete*(self: WalletModel) =
   discard
 
-proc sendTransaction*(self: WalletModel, source, to, assetAddress, value, gas, gasPrice, password: string): RpcResponse =
-  var
-    weiValue = eth2Wei(parseFloat(value), 18) # ETH
-    data = ""
-    toAddr = parseAddress(to)
-  let gasPriceInWei = gwei2Wei(parseFloat(gasPrice))
+proc buildTokenTransaction(self: WalletModel, source, to, assetAddress: EthAddress, value: float, transfer: var Transfer, contract: var Contract, gas = "", gasPrice = ""): EthSend =
+  let token = self.tokens.first("address", $assetAddress)
+  contract = getContract("snt")
+  transfer = Transfer(to: to, value: eth2Wei(value, token["decimals"].getInt))
+  transactions.buildTokenTransaction(source, assetAddress, gas, gasPrice)
 
-  # TODO: this code needs to be tested with testnet assets (to be implemented in
-  # a future PR
-  if assetAddress != ZERO_ADDRESS and not assetAddress.isEmptyOrWhitespace:
-    let
-      token = self.tokens.first("address", assetAddress)
-      contract = getContract("snt")
-      transfer = Transfer(to: toAddr, value: eth2Wei(parseFloat(value), token["decimals"].getInt))
-    weiValue = 0.u256
-    data = contract.methods["transfer"].encodeAbi(transfer)
-    toAddr = parseAddress(assetAddress)
-
-  let tx = EthSend(
-    source: parseAddress(source),
-    to: toAddr.some,
-    gas: (if gas.isEmptyOrWhitespace: Quantity.none else: Quantity(cast[uint64](parseFloat(gas).toUInt64)).some),
-    gasPrice: (if gasPrice.isEmptyOrWhitespace: int.none else: gwei2Wei(parseFloat(gasPrice)).truncate(int).some),
-    value: weiValue.some,
-    data: data
+proc estimateGas*(self: WalletModel, source, to, value: string): int =
+  var tx = transactions.buildTransaction(
+    parseAddress(source),
+    eth2Wei(parseFloat(value), 18)
   )
+  tx.to = parseAddress(to).some
   try:
-    result = status_wallet.sendTransaction(tx, password)
+    let response = eth.estimateGas(tx)
+    result = fromHex[int](response)
+  except RpcException as e:
+    raise
+
+proc estimateTokenGas*(self: WalletModel, source, to, assetAddress, value: string): int =
+  var
+    transfer: Transfer
+    contract: Contract
+    tx = self.buildTokenTransaction(
+      parseAddress(source),
+      parseAddress(to),
+      parseAddress(assetAddress),
+      parseFloat(value),
+      transfer,
+      contract
+    )
+  try:
+    let response = contract.methods["transfer"].estimateGas(tx, transfer)
+    result = fromHex[int](response)
+  except RpcException as e:
+    raise
+
+proc sendTransaction*(self: WalletModel, source, to, value, gas, gasPrice, password: string): string =
+  var tx = transactions.buildTransaction(
+    parseAddress(source),
+    eth2Wei(parseFloat(value), 18), gas, gasPrice
+  )
+  tx.to = parseAddress(to).some
+
+  try:
+    result = eth.sendTransaction(tx, password)
+  except RpcException as e:
+    raise
+
+proc sendTokenTransaction*(self: WalletModel, source, to, assetAddress, value, gas, gasPrice, password: string): string =
+  var
+    transfer: Transfer
+    contract: Contract
+    tx = self.buildTokenTransaction(
+      parseAddress(source),
+      parseAddress(to),
+      parseAddress(assetAddress),
+      parseFloat(value),
+      transfer,
+      contract,
+      gas,
+      gasPrice
+    )
+  try:
+    result = contract.methods["transfer"].send(tx, transfer, password)
   except RpcException as e:
     raise
 
@@ -88,10 +124,15 @@ proc getDefaultCurrency*(self: WalletModel): string =
 
 # TODO: This needs to be removed or refactored so that test tokens are shown
 # when on testnet https://github.com/status-im/nim-status-client/issues/613.
-proc getStatusTokenSymbol*(self: WalletModel): string =
+proc getStatusToken*(self: WalletModel): string =
+  var token = Asset(address: $getContract("snt").address)
   if status_settings.getCurrentNetwork() == Network.Testnet:
-    return "STT"
-  "SNT"
+    token.name = "Status Test Token"
+    token.symbol = "STT"
+  else:
+    token.name = "Status Network Token"
+    token.symbol = "SNT"
+  result = $(%token)
 
 proc setDefaultCurrency*(self: WalletModel, currency: string) =
   discard status_settings.saveSetting(Setting.Currency, currency)

src/status/wallet/collectibles.nim

@@ -1,7 +1,7 @@
 import strformat, httpclient, json, chronicles, sequtils, strutils, tables, sugar
 from eth/common/utils import parseAddress
 import ../libstatus/core as status
-import ../libstatus/contracts as contracts
+import ../libstatus/eth/contracts as contracts
 import ../libstatus/stickers as status_stickers
 import ../chat as status_chat
 import ../libstatus/types

ui/app/AppLayouts/Chat/components/StickerPackPurchaseModal.qml

@@ -7,7 +7,7 @@ import "../../../../shared"
 
 ModalPopup {
     id: root
-    property var asset: { "name": "Status", "symbol": walletModel.getStatusTokenSymbol() }
+    readonly property var asset: JSON.parse(walletModel.getStatusToken())
     property int stickerPackId: -1
     property string packPrice
     property bool showBackBtn: false
@@ -90,6 +90,7 @@ ModalPopup {
                     showBalanceForAssetSymbol = Qt.binding(function() { return root.asset.symbol })
                     minRequiredAssetBalance = Qt.binding(function() { return root.packPrice })
                 }
+                onSelectedAccountChanged: gasSelector.estimateGas()
             }
             RecipientSelector {
                 id: selectRecipient
@@ -98,6 +99,7 @@ ModalPopup {
                 contacts: profileModel.addedContacts
                 selectedRecipient: { "address": chatsModel.stickerMarketAddress, "type": RecipientSelector.Type.Address }
                 readOnly: true
+                onSelectedRecipientChanged: gasSelector.estimateGas()
             }
             GasSelector {
                 id: gasSelector
@@ -107,19 +109,17 @@ ModalPopup {
                 getGasEthValue: walletModel.getGasEthValue
                 getFiatValue: walletModel.getFiatValue
                 defaultCurrency: walletModel.defaultCurrency
-                selectedGasLimit: { return getDefaultGasLimit() }
                 reset: function() {
                     slowestGasPrice = Qt.binding(function(){ return parseFloat(walletModel.safeLowGasPrice) })
                     fastestGasPrice = Qt.binding(function(){ return parseFloat(walletModel.fastestGasPrice) })
-                    selectedGasLimit = Qt.binding(getDefaultGasLimit)
                 }
-
-                function getDefaultGasLimit() {
-                    if (root.stickerPackId > -1 && selectFromAccount.selectedAccount && root.packPrice && parseFloat(root.packPrice) > 0) {
-                        return chatsModel.getStickerBuyPackGasEstimate(root.stickerPackId, selectFromAccount.selectedAccount.address, root.packPrice)
+                property var estimateGas: Backpressure.debounce(gasSelector, 600, function() {
+                    if (!(root.stickerPackId > -1 && selectFromAccount.selectedAccount && root.packPrice && parseFloat(root.packPrice) > 0)) {
+                        selectedGasLimit = 325000
+                        return
                     }
-                    return 200000
-                }
+                    selectedGasLimit = chatsModel.buyPackGasEstimate(root.stickerPackId, selectFromAccount.selectedAccount.address, root.packPrice)
+                })
             }
             GasValidator {
                 id: gasValidator

ui/app/AppLayouts/Wallet/SendModal.qml

@@ -83,6 +83,7 @@ ModalPopup {
                     accounts = Qt.binding(function() { return walletModel.accounts })
                     selectedAccount = Qt.binding(function() { return walletModel.currentAccount })
                 }
+                onSelectedAccountChanged: gasSelector.estimateGas()
             }
             SeparatorWithIcon {
                 id: separator
@@ -102,6 +103,7 @@ ModalPopup {
                     contacts = Qt.binding(function() { return profileModel.addedContacts })
                     selectedRecipient = {}
                 }
+                onSelectedRecipientChanged: gasSelector.estimateGas()
             }
         }
         TransactionFormGroup {
@@ -119,6 +121,8 @@ ModalPopup {
                 reset: function() {
                     selectedAccount = Qt.binding(function() { return selectFromAccount.selectedAccount })
                 }
+                onSelectedAssetChanged: gasSelector.estimateGas()
+                onSelectedAmountChanged: gasSelector.estimateGas()
             }
             GasSelector {
                 id: gasSelector
@@ -134,6 +138,24 @@ ModalPopup {
                     slowestGasPrice = Qt.binding(function(){ return parseFloat(walletModel.safeLowGasPrice) })
                     fastestGasPrice = Qt.binding(function(){ return parseFloat(walletModel.fastestGasPrice) })
                 }
+                property var estimateGas: Backpressure.debounce(gasSelector, 600, function() {
+                    if (!(selectFromAccount.selectedAccount && selectFromAccount.selectedAccount.address &&
+                        selectRecipient.selectedRecipient && selectRecipient.selectedRecipient.address &&
+                        txtAmount.selectedAsset && txtAmount.selectedAsset.address &&
+                        txtAmount.selectedAmount)) return
+                    
+                    let gasEstimate = JSON.parse(walletModel.estimateGas(
+                        selectFromAccount.selectedAccount.address,
+                        selectRecipient.selectedRecipient.address,
+                        txtAmount.selectedAsset.address,
+                        txtAmount.selectedAmount))
+
+                    if (gasEstimate.error) {
+                        console.warn(qsTr("Error estimating gas: %1").arg(gasEstimate.error.message))
+                        return
+                    }
+                    selectedGasLimit = gasEstimate.result
+                })
             }
             GasValidator {
                 id: gasValidator

ui/shared/GasValidator.qml

@@ -37,7 +37,7 @@ Item {
         }
         txtValidationError.text = ""
         let gasTotal = selectedGasEthValue
-        if (selectedAsset && selectedAsset.symbol.toUpperCase() === "ETH") {
+        if (selectedAsset && selectedAsset.symbol && selectedAsset.symbol.toUpperCase() === "ETH") {
             gasTotal += selectedAmount
         }
         const currAcctGasAsset = Utils.findAssetBySymbol(selectedAccount.assets, "ETH")