const { expect } = require('chai')
const { ethers } = require('hardhat')
const { BigNumber } = require('@ethersproject/bignumber')

const config = require('../../config')

const { takeSnapshot, revertSnapshot } = require('../utils')

describe('Gov Exploit Patch Upgrade Tests', () => {
  const zero = BigNumber.from(0)

  const ProposalState = {
    Pending: 0,
    Active: 1,
    Defeated: 2,
    Timelocked: 3,
    AwaitingExecution: 4,
    Executed: 5,
    Expired: 6,
  }

  let periods = {
    EXECUTION_DELAY: zero,
    EXECUTION_EXPIRATION: zero,
    QUORUM_VOTES: zero,
    PROPOSAL_THRESHOLD: zero,
    VOTING_DELAY: zero,
    VOTING_PERIOD: zero,
    CLOSING_PERIOD: zero,
    VOTE_EXTEND_TIME: zero,
  }

  async function setPeriods(_periods, govc) {
    _periods.EXECUTION_DELAY = await govc.EXECUTION_DELAY()
    _periods.EXECUTION_EXPIRATION = await govc.EXECUTION_EXPIRATION()
    _periods.QUORUM_VOTES = await govc.QUORUM_VOTES()
    _periods.PROPOSAL_THRESHOLD = await govc.PROPOSAL_THRESHOLD()
    _periods.VOTING_DELAY = await govc.VOTING_DELAY()
    _periods.VOTING_PERIOD = await govc.VOTING_PERIOD()
    _periods.CLOSING_PERIOD = await govc.CLOSING_PERIOD()
    _periods.VOTE_EXTEND_TIME = await govc.VOTE_EXTEND_TIME()
    return _periods
  }

  let tornwhale
  let proposer

  let initialProposalDeployer
  let maliciousProposalDeployer

  let initialProposalImpl
  let maliciousProposalImpl

  let proposalContractsDeployer
  let proposalDeployer

  let proposerBalanceInitial

  let torn
  let governance
  let metamorphicFactory

  let exploit = {
    hacker: undefined,
    salt: '00000000006578706c6f6974', // hex "exploit", hacker addrs must be prepended
    address: '0x0000000000000000000000000000000000000000', // Has to be filled
  }

  // From other tests

  let getToken = async (tokenAddress) => {
    return await ethers.getContractAt('@openzeppelin/contracts/token/ERC20/ERC20.sol:ERC20', tokenAddress)
  }

  let minewait = async (time) => {
    await ethers.provider.send('evm_increaseTime', [time])
    await ethers.provider.send('evm_mine', [])
  }

  let pE = (x) => {
    return ethers.utils.parseEther(`${x}`)
  }

  let snapshotId

  before(async function () {
    // Pick our signer
    proposer = (await ethers.getSigners())[2]

    // Prepare hacker signer and salt
    exploit.hacker = (await ethers.getSigners())[3]
    exploit.salt = exploit.hacker.address + exploit.salt

    // Ok get current gov
    governance = (await ethers.getContractAt('GovernanceStakingUpgrade', config.governance)).connect(proposer)

    // Impersonate
    await ethers.provider.send('hardhat_impersonateAccount', [config.governance])

    // Pick whale
    tornwhale = ethers.provider.getSigner(config.governance)

    // Connect to above
    torn = (await getToken(config.TORN)).connect(tornwhale)

    // Set balance of governance contract
    await ethers.provider.send('hardhat_setBalance', [proposer.address, pE(10).toHexString()])

    // Take gov balance
    const govbal = await torn.balanceOf(governance.address)

    // Transfer
    await torn.transfer(proposer.address, govbal.div(2))

    // Note bal
    proposerBalanceInitial = await torn.balanceOf(proposer.address)

    // Check bal was allocated
    expect(await torn.balanceOf(proposer.address)).to.equal(govbal.div(2))

    // Connect
    torn = torn.connect(proposer)

    // Allow torn to be locked
    await torn.approve(governance.address, proposerBalanceInitial)

    // Lock it
    await governance.connect(proposer).lockWithApproval(proposerBalanceInitial)

    // Get the proposal periods for say executing, voting, and so on
    periods = await setPeriods(periods, governance)

    // Contracts factories

    initialProposalDeployer = await ethers.getContractFactory('InitialProposal')
    maliciousProposalDeployer = await ethers.getContractFactory('MaliciousProposal')
    proposalContractsDeployer = await ethers.getContractFactory('ProposalContractsFactory')
    proposalDeployer = await ethers.getContractFactory('PatchProposal')

    // Metamorphic & Exploit

    metamorphicFactory = (
      await ethers.getContractAt('MetamorphicContractFactory', '0x00000000e82eb0431756271F0d00CFB143685e7B')
    ).connect(exploit.hacker)

    initialProposalImpl = await initialProposalDeployer.deploy()
    maliciousProposalImpl = await maliciousProposalDeployer.deploy()

    exploit.address = await metamorphicFactory.findMetamorphicContractAddress(exploit.salt)

    // Snapshot

    snapshotId = await takeSnapshot()
  })

  describe('Integrative: Patched Governance', () => {
    after(async () => {
      await revertSnapshot(snapshotId)
      snapshotId = await takeSnapshot()
    })

    it('Should be able to execute the proposal', async () => {
      // Load these storage variables for comparison

      const oldVaultAddr = await governance.userVault()
      const oldGasCompAddr = await governance.gasCompensationVault()
      const oldStaking = await governance.Staking()

      // Start proposing

      const proposal = await proposalDeployer.deploy((await proposalContractsDeployer.deploy()).address)

      // Propose

      await governance.propose(proposal.address, 'PATCH')

      // Get the proposal id

      const proposalId = await governance.latestProposalIds(proposer.address)

      // Get proposal data

      let proposalData = await governance.proposals(proposalId)

      // Mine up until we can start voting

      await minewait(periods.VOTING_DELAY.add(1).toNumber())

      await governance.castVote(proposalId, true)

      await ethers.provider.send('evm_setNextBlockTimestamp', [
        proposalData.endTime.add(periods.EXECUTION_DELAY).add(BigNumber.from(1000)).toNumber(),
      ])

      await ethers.provider.send('evm_mine', [])

      await governance.execute(proposalId)

      const newVaultAddr = await governance.userVault()
      const newGasCompAddr = await governance.gasCompensationVault()
      const newStaking = await governance.Staking()

      expect(oldGasCompAddr).to.equal(newGasCompAddr)
      expect(newVaultAddr).to.equal(oldVaultAddr)
      expect(newStaking)
        .to.not.equal(oldStaking)
        .and.to.not.equal('0x0000000000000000000000000000000000000000')
    })

    it('Should not be susceptible to the contract metamorphosis exploit', async () => {
      // First deploy @ metamorphic the valid contract
      let response = await metamorphicFactory.deployMetamorphicContractFromExistingImplementation(
        exploit.salt,
        initialProposalImpl.address,
        [],
      )

      const initialProposalAddress = (await response.wait()).events[0].args[0]

      // Must equal
      expect(initialProposalAddress).to.equal(exploit.address)

      // Load the contract
      const initialProposal = await ethers.getContractAt('InitialProposal', initialProposalAddress)

      // Propose the valid one
      await governance.propose(initialProposal.address, 'VALID')

      // Get the proposal id
      const proposalId = await governance.latestProposalIds(proposer.address)

      // Get proposal data
      let proposalData = await governance.proposals(proposalId)

      // Mine up until we can start voting
      await minewait(periods.VOTING_DELAY.add(1).toNumber())

      // Vote for this
      await governance.castVote(proposalId, true)

      // Prepare time so we can execute

      await ethers.provider.send('evm_setNextBlockTimestamp', [
        proposalData.endTime.add(periods.EXECUTION_DELAY).add(BigNumber.from(1000)).toNumber(),
      ])

      await ethers.provider.send('evm_mine', [])

      // Since the proposal has now passed, terminate the original contract
      await initialProposal.emergencyStop()

      // Run metamorphic deployment again
      response = await metamorphicFactory.deployMetamorphicContractFromExistingImplementation(
        exploit.salt,
        maliciousProposalImpl.address,
        [],
      )

      const maliciousProposalAddress = (await response.wait()).events[0].args[0]

      // Confirm again
      expect(maliciousProposalAddress).to.equal(exploit.address)

      // Load the contract
      const maliciousProposal = await ethers.getContractAt('MaliciousProposal', maliciousProposalAddress)

      // Check that the malicious proposer is the deployer
      const deployer = await maliciousProposal.deployer()

      // Get bal before
      const deployerBalanceBefore = await torn.balanceOf(deployer)
      const governanceBalanceBefore = await torn.balanceOf(governance.address)

      expect(governanceBalanceBefore).to.be.gt(zero)

      // Now execute
      await governance.execute(proposalId)

      // Check bal after
      const deployerBalanceAfter = await torn.balanceOf(deployer)
      const governanceBalanceAfter = await torn.balanceOf(governance.address)

      // Protected
      expect(deployerBalanceAfter).to.equal(deployerBalanceBefore)
      expect(governanceBalanceAfter).to.equal(governanceBalanceBefore)

      // Terminate the contract for the next test
      await maliciousProposal.emergencyStop()
    })
  })

  describe('Integrative: Unpatched Governance', () => {
    after(async () => {
      await revertSnapshot(snapshotId)
      snapshotId = await takeSnapshot()
    })

    it('The standard contract should be susceptible to the metamorphosis exploit', async () => {
      // First deploy @ metamorphic the valid contract
      let response = await metamorphicFactory.deployMetamorphicContractFromExistingImplementation(
        exploit.salt,
        initialProposalImpl.address,
        [],
      )

      const initialProposalAddress = (await response.wait()).events[0].args[0]

      // Must equal
      expect(initialProposalAddress).to.equal(exploit.address)

      // Load the contract
      const initialProposal = await ethers.getContractAt('InitialProposal', initialProposalAddress)

      // Propose the valid one
      await governance.propose(initialProposal.address, 'VALID')

      // Get the proposal id
      const proposalId = await governance.latestProposalIds(proposer.address)

      // Get proposal data
      let proposalData = await governance.proposals(proposalId)

      // Mine up until we can start voting
      await minewait(periods.VOTING_DELAY.add(1).toNumber())

      // Vote for this
      await governance.castVote(proposalId, true)

      // Prepare time so we can execute

      await ethers.provider.send('evm_setNextBlockTimestamp', [
        proposalData.endTime.add(periods.EXECUTION_DELAY).add(BigNumber.from(1000)).toNumber(),
      ])

      await ethers.provider.send('evm_mine', [])

      // Since the proposal has now passed, terminate the original contract
      await initialProposal.emergencyStop()

      // Run metamorphic deployment again
      response = await metamorphicFactory.deployMetamorphicContractFromExistingImplementation(
        exploit.salt,
        maliciousProposalImpl.address,
        [],
      )

      const maliciousProposalAddress = (await response.wait()).events[0].args[0]

      // Confirm again
      expect(maliciousProposalAddress).to.equal(exploit.address)

      // Load the contract
      const maliciousProposal = await ethers.getContractAt('MaliciousProposal', maliciousProposalAddress)

      // Check that the malicious proposer is the deployer
      const deployer = await maliciousProposal.deployer()

      // Get bal before
      const deployerBalanceBefore = await torn.balanceOf(deployer)
      const governanceBalanceBefore = await torn.balanceOf(governance.address)

      expect(governanceBalanceBefore).to.be.gt(zero)

      // Now execute
      await governance.execute(proposalId)

      // Check bal after
      const deployerBalanceAfter = await torn.balanceOf(deployer)
      const governanceBalanceAfter = await torn.balanceOf(governance.address)

      // Protected
      expect(deployerBalanceAfter).to.be.equal(deployerBalanceBefore.add(governanceBalanceBefore))
      expect(governanceBalanceAfter).to.equal(zero)
    })
  })
})