NFT-Collateralized Lending Platform - Diamond Contract Architecture

This project is a decentralized peer-2-peer lending platform that allows users to collateralize NFTs in exchange for cryptocurrency loans. Built using the Diamond Standard (EIP-2535), this contract system offers modular, upgradable, and gas-efficient smart contracts, enabling easy addition and modification of features.

Features

• NFT Collateralization: Borrowers can lock up NFTs as collateral for loans.
• Lenders: Lenders select any loan term they like and grant loan while waiting for interest.
• Diamond Contract Structure: Using facets to modularize functionality, including LoanFacet, LenderFacet, and RepaymentFacet.
• Flexible Loan Terms: Customizable loan amounts, durations, and interest rates.
• Escrow Management: The platform acts as an escrow, transferring collateralized NFTs to lenders if loans are not repaid.
• Time Simulation (for Testing): Loan expiry and repayment scenarios can be tested with time manipulation.

Project Structure

Contracts

• Diamond.sol: Implements the core Diamond Proxy logic, delegating calls to facets based on function selectors.
• LoanFacet.sol: Contains functionality for creating loan terms, transferring NFT collateral, and loan state management.
• LenderFacet.sol: Handles lender interactions, such as accepting loans and force-closing on defaults.
• RepaymentFacet.sol: Manages repayments, interest calculation, and updating loan status.
• LibDiamond.sol: Manages shared state variables (loan data, mappings) and stores diamond-related data.

Testing

Tests are written using Foundry to simulate different lending scenarios. Tests include:

• Loan creation and validation.
• Time-based tests for loan expiration.
• Forced loan closures and collateral transfers.

Deployment & Testing Tools

• Foundry: For testing, debugging, and simulating blockchain environments.
• OpenZeppelin Contracts: For ERC20 and ERC721 token standards.
• Solidity Console: Used in debugging to log state changes.

Installation

1. Clone the repository:

   git clone git@github.com:Guzbyte-tech/NFTcollateral_Lending_Contract_Diamond.git
   cd NFTcollateral_Lending_Contract_Diamond

2. Install Foundry: Follow the Foundry installation guide here.

3. Install dependencies:

   forge install

4. Compile the contracts:

   forge build

Running Tests

Tests are located in the test directory and use the Foundry testing framework. Run all tests using:

forge test

To simulate time in tests, Foundry’s vm.warp is used to control block.timestamp.

Example Usage

1. Create a Loan:

   • Borrowers call createLoanTerms on the LoanFacet, specifying currency, amount, interest, and collateral NFT details.

2. Lender Acceptance:

   • Lenders can accept a loan, initiating the loan duration and transferring tokens to the borrower.

3. Repayment:

   • Borrowers repay the loan within the duration specified, paying principal plus interest.

4. Force Closure:

   • If the borrower fails to repay, the lender can call forceCloseLoan to transfer the NFT collateral to their address.

Contributing

1. Fork the project
2. Create a feature branch: git checkout -b feature-name
3. Commit your changes: git commit -m 'Add some feature'
4. Push to the branch: git push origin feature-name
5. Open a pull request

License

This project is licensed under the MIT License.