Bank smart contract

• Anyone can deposit any amount of wizard ($WZD) ERC20 tokens to their savings (staking) account.
  
• The Bank contract contains an additional token reward pool of R $WZD tokens.
  
• A staking reward is generated for the users, depending on the time passed before token withrawal.
  

Contract dynamics

DEPLOYMENT

• The contract is deployed at t0
  
• The Bank owner sets a time period constant T, used for reward calculation.
  
• The owner also deposits an amount R of reward tokens, split into 3 subpools:
  R1 = 20% of R, available after 2T has passed since contract deployment
  R2 = 30% of R, available after 3T has passed since contract deployment
  R3 = 50% of R, available after 4T has passed since contract deployment
  

DEPOSIT

The deposit period goes from t0 to t0 + T.

During this period, users can use the deposit method to save their $WZD tokens into the contract. After T has passed, no more deposits are allowed.

LOCK

This period goes from moment t0+T to t0+2T

Users cannot withdraw their tokens (If the user tries to remove tokens before T time has elapsed since they have deposited, the transaction will fail).

WITHRAW

After 2T has passed since contract deployment, the users can withdraw their tokens. However, the longer they wait, the bigger the reward they get. The amount of tokens each user receives will be proportional to their stake in the contract relative to the total staking for every time period.

There are three withdraw periods:

First Unlock --> from t0 + 2T to t0 + 3T

A user withdrawing during the first unlock will collect an additional amount of $WZD tokens from R1.

Second Unlock --> from t0 + 3T to t0 + 4T

A user withdrawing during the second unlock will collect an additional amount of $WZD tokens from R1 + R2.

Third Unlock --> from t0 + 4T

A user withdrawing during the second unlock will collect an additional amount of $WZD tokens from R1 + R2 + R3.

RETRIEVE

If no user waits for the third unlock to withdraw their tokens, the remaining tokens on the contract can be withdrawn by the bank (contract owner). In no other situation can the bank owner remove tokens from the contract.

QUICKSTART 🚀

Download the Hardhat repo and play around with tests, tasks or your own scripts:

git clone https://github.com/fields93/staking-bank.git

Networks

This project can run on:
🥇Hardhat Network
🥈Hardhat Localhost Testnet
🥉Ethereum Rinkeby Testnet

In the following sections, the different available interactions with each network wil be explained.

🥇 Hardhat Network

This network is used for testing.

Deploy your contracts:

yarn deploy

Test your contracts:

yarn test

Check the test coverage with the plugin Solidity Coverage:

yarn coverage

🥈Hardhat Localhost Testnet

In order to interact with this network, you will first need to start a Hardhat Node in a different terminal:

yarn hardhat node

Deploy your contracts:

yarn deploy-localhost

Test your contracts:

yarn test-localhost

🥉 Ethereum Rinkeby Testnet

Both the Bank and the Wizard (ERC20 token) contracts have been already deployed and verified on Rinkebyscan at:

• Bank: 0x4B146B7AFcF4f5D74faedb71d6Ab41A7FF5ECa9e
• Wizard: 0xA3048A8e2aabbdCe7A47685B8991EE58EeCeE47f

However, if you wish to deploy new contracts from your account and verify them, you can do it by running:

yarn deploy-rinkeby

To verify, first you will need to update the contract addresses in scripts/verify-contract.js and then run:

yarn verify

Interact with the Rinkeby-deployed contracts

In this case, there are no available tests. Instead, some tasks have been added to the project in order to interact with the contracts deployed on Rinkeby. The available tasks are:

Get the balance of $WZD tokens in your wallet:

yarn task-balance

Mint tokens:

yarn task-mint AMOUNT

Deposit tokens:

yarn task-deposit AMOUNT

Withdraw tokens:

yarn task-withdraw AMOUNT

Retrieve tokens:

yarn task-retrieve AMOUNT