token.go

package tomox

import (
	"context"
	"github.com/tomochain/tomochain/log"
	"math/big"
	"strings"

	"github.com/tomochain/tomochain"
	"github.com/tomochain/tomochain/accounts/abi"
	"github.com/tomochain/tomochain/accounts/abi/bind/backends"
	"github.com/tomochain/tomochain/common"
	"github.com/tomochain/tomochain/consensus"
	"github.com/tomochain/tomochain/core/state"
)

const tokenAbi = `
[
  {
    "constant": true,
    "inputs": [],
    "name": "name",
    "outputs": [
      {
        "name": "",
        "type": "string"
      }
    ],
    "payable": false,
    "stateMutability": "view",
    "type": "function",
    "signature": "0x06fdde03"
  },
  {
    "constant": false,
    "inputs": [
      {
        "name": "spender",
        "type": "address"
      },
      {
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "approve",
    "outputs": [
      {
        "name": "",
        "type": "bool"
      }
    ],
    "payable": false,
    "stateMutability": "nonpayable",
    "type": "function",
    "signature": "0x095ea7b3"
  },
  {
    "constant": true,
    "inputs": [],
    "name": "totalSupply",
    "outputs": [
      {
        "name": "",
        "type": "uint256"
      }
    ],
    "payable": false,
    "stateMutability": "view",
    "type": "function",
    "signature": "0x18160ddd"
  },
  {
    "constant": false,
    "inputs": [
      {
        "name": "from",
        "type": "address"
      },
      {
        "name": "to",
        "type": "address"
      },
      {
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "transferFrom",
    "outputs": [
      {
        "name": "",
        "type": "bool"
      }
    ],
    "payable": false,
    "stateMutability": "nonpayable",
    "type": "function",
    "signature": "0x23b872dd"
  },
  {
    "constant": true,
    "inputs": [],
    "name": "decimals",
    "outputs": [
      {
        "name": "",
        "type": "uint8"
      }
    ],
    "payable": false,
    "stateMutability": "view",
    "type": "function",
    "signature": "0x313ce567"
  },
  {
    "constant": true,
    "inputs": [],
    "name": "cap",
    "outputs": [
      {
        "name": "",
        "type": "uint256"
      }
    ],
    "payable": false,
    "stateMutability": "view",
    "type": "function",
    "signature": "0x355274ea"
  },
  {
    "constant": false,
    "inputs": [
      {
        "name": "spender",
        "type": "address"
      },
      {
        "name": "addedValue",
        "type": "uint256"
      }
    ],
    "name": "increaseAllowance",
    "outputs": [
      {
        "name": "",
        "type": "bool"
      }
    ],
    "payable": false,
    "stateMutability": "nonpayable",
    "type": "function",
    "signature": "0x39509351"
  },
  {
    "constant": false,
    "inputs": [
      {
        "name": "to",
        "type": "address"
      },
      {
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "mint",
    "outputs": [
      {
        "name": "",
        "type": "bool"
      }
    ],
    "payable": false,
    "stateMutability": "nonpayable",
    "type": "function",
    "signature": "0x40c10f19"
  },
  {
    "constant": true,
    "inputs": [
      {
        "name": "owner",
        "type": "address"
      }
    ],
    "name": "balanceOf",
    "outputs": [
      {
        "name": "",
        "type": "uint256"
      }
    ],
    "payable": false,
    "stateMutability": "view",
    "type": "function",
    "signature": "0x70a08231"
  },
  {
    "constant": true,
    "inputs": [],
    "name": "symbol",
    "outputs": [
      {
        "name": "",
        "type": "string"
      }
    ],
    "payable": false,
    "stateMutability": "view",
    "type": "function",
    "signature": "0x95d89b41"
  },
  {
    "constant": false,
    "inputs": [
      {
        "name": "account",
        "type": "address"
      }
    ],
    "name": "addMinter",
    "outputs": [],
    "payable": false,
    "stateMutability": "nonpayable",
    "type": "function",
    "signature": "0x983b2d56"
  },
  {
    "constant": false,
    "inputs": [],
    "name": "renounceMinter",
    "outputs": [],
    "payable": false,
    "stateMutability": "nonpayable",
    "type": "function",
    "signature": "0x98650275"
  },
  {
    "constant": false,
    "inputs": [
      {
        "name": "spender",
        "type": "address"
      },
      {
        "name": "subtractedValue",
        "type": "uint256"
      }
    ],
    "name": "decreaseAllowance",
    "outputs": [
      {
        "name": "",
        "type": "bool"
      }
    ],
    "payable": false,
    "stateMutability": "nonpayable",
    "type": "function",
    "signature": "0xa457c2d7"
  },
  {
    "constant": false,
    "inputs": [
      {
        "name": "to",
        "type": "address"
      },
      {
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "transfer",
    "outputs": [
      {
        "name": "",
        "type": "bool"
      }
    ],
    "payable": false,
    "stateMutability": "nonpayable",
    "type": "function",
    "signature": "0xa9059cbb"
  },
  {
    "constant": true,
    "inputs": [
      {
        "name": "account",
        "type": "address"
      }
    ],
    "name": "isMinter",
    "outputs": [
      {
        "name": "",
        "type": "bool"
      }
    ],
    "payable": false,
    "stateMutability": "view",
    "type": "function",
    "signature": "0xaa271e1a"
  },
  {
    "constant": true,
    "inputs": [
      {
        "name": "owner",
        "type": "address"
      },
      {
        "name": "spender",
        "type": "address"
      }
    ],
    "name": "allowance",
    "outputs": [
      {
        "name": "",
        "type": "uint256"
      }
    ],
    "payable": false,
    "stateMutability": "view",
    "type": "function",
    "signature": "0xdd62ed3e"
  },
  {
    "inputs": [
      {
        "name": "name",
        "type": "string"
      },
      {
        "name": "symbol",
        "type": "string"
      },
      {
        "name": "totalSupply",
        "type": "uint256"
      },
      {
        "name": "decimals",
        "type": "uint8"
      }
    ],
    "payable": false,
    "stateMutability": "nonpayable",
    "type": "constructor",
    "signature": "constructor"
  },
  {
    "anonymous": false,
    "inputs": [
      {
        "indexed": true,
        "name": "account",
        "type": "address"
      }
    ],
    "name": "MinterAdded",
    "type": "event",
    "signature": "0x6ae172837ea30b801fbfcdd4108aa1d5bf8ff775444fd70256b44e6bf3dfc3f6"
  },
  {
    "anonymous": false,
    "inputs": [
      {
        "indexed": true,
        "name": "account",
        "type": "address"
      }
    ],
    "name": "MinterRemoved",
    "type": "event",
    "signature": "0xe94479a9f7e1952cc78f2d6baab678adc1b772d936c6583def489e524cb66692"
  },
  {
    "anonymous": false,
    "inputs": [
      {
        "indexed": true,
        "name": "from",
        "type": "address"
      },
      {
        "indexed": true,
        "name": "to",
        "type": "address"
      },
      {
        "indexed": false,
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "Transfer",
    "type": "event",
    "signature": "0xddf252ad1be2c89b69c2b068fc378daa952ba7f163c4a11628f55a4df523b3ef"
  },
  {
    "anonymous": false,
    "inputs": [
      {
        "indexed": true,
        "name": "owner",
        "type": "address"
      },
      {
        "indexed": true,
        "name": "spender",
        "type": "address"
      },
      {
        "indexed": false,
        "name": "value",
        "type": "uint256"
      }
    ],
    "name": "Approval",
    "type": "event",
    "signature": "0x8c5be1e5ebec7d5bd14f71427d1e84f3dd0314c0f7b2291e5b200ac8c7c3b925"
  }
]`

// GetTokenAbi return token abi
func GetTokenAbi() (*abi.ABI, error) {
	contractABI, err := abi.JSON(strings.NewReader(tokenAbi))
	if err != nil {
		return nil, err
	}
	return &contractABI, nil
}

// RunContract run smart contract
func RunContract(chain consensus.ChainContext, statedb *state.StateDB, coinbase common.Address, contractAddr common.Address, abi *abi.ABI, method string, args ...interface{}) (interface{}, error) {
	input, err := abi.Pack(method)
	if err != nil {
		return nil, err
	}
	backend := (*backends.SimulatedBackend)(nil)
	msg := ethereum.CallMsg{To: &contractAddr, Data: input, From: coinbase}
	result, err := backend.CallContractWithState(context.Background(), msg, chain, statedb)
	if err != nil {
		return nil, err
	}
	var unpackResult interface{}
	err = abi.Unpack(&unpackResult, method, result)
	if err != nil {
		return nil, err
	}
	return unpackResult, nil
}

func (tomox *TomoX) GetTokenDecimal(chain consensus.ChainContext, statedb *state.StateDB, coinbase common.Address, tokenAddr common.Address) (*big.Int, error) {
	if tokenDecimal, ok := tomox.tokenDecimalCache.Get(tokenAddr); ok {
		return tokenDecimal.(*big.Int), nil
	}
	if tokenAddr.String() == common.TomoNativeAddress {
		tomox.tokenDecimalCache.Add(tokenAddr, common.BasePrice)
		return common.BasePrice, nil
	}
	var decimals uint8
	defer func() {
		log.Debug("GetTokenDecimal from ", "relayerSMC", common.RelayerRegistrationSMC, "tokenAddr", tokenAddr.Hex(), "decimals", decimals)
	}()
	contractABI, err := GetTokenAbi()
	if err != nil {
		return nil, err
	}
	stateCopy := statedb.Copy()
	result, err := RunContract(chain, stateCopy, coinbase, tokenAddr, contractABI, "decimals")
	if err != nil {
		return nil, err
	}
	decimals = result.(uint8)

	tokenDecimal := new(big.Int).SetUint64(0).Exp(big.NewInt(10), big.NewInt(int64(decimals)), nil)
	tomox.tokenDecimalCache.Add(tokenAddr, tokenDecimal)
	return tokenDecimal, nil
}