Multi-Utility NFT Contract

Overview

The MultiNFT contract is a versatile ERC721-based NFT contract that supports phased minting, discounted minting with signatures, and vesting functionality. It is designed to handle three distinct minting phases:

Phase 1: Whitelisted users can mint NFTs for free using Merkle proofs.

Phase 2: Selected users can mint NFTs at a discounted price using Merkle proofs and signatures.

Phase 3: Open minting for everyone at the full price.

Additionally, the contract includes a vesting mechanism that locks minting fees in a linear vesting schedule, allowing the contract owner to claim vested tokens over time.

Usage

Phased Minting:

• Phase 1: Free minting for whitelisted users (verified via Merkle proofs).
• Phase 2: Discounted minting for selected users (verified via Merkle proofs and signatures).
• Phase 3: Open minting for everyone at the full price.

Vesting Mechanism:

• Minting fees are locked in a linear vesting schedule for one year.
• Only the contract owner can claim vested tokens.

Security:

• Uses OpenZeppelin's ReentrancyGuard to prevent reentrancy attacks.
• Ensures signatures are not reused.
• Validates Merkle proofs to prevent unauthorized minting.

Flexibility:

• The contract owner can update the minting phase and transfer ownership.

Usage

• Set the Minting Phase:

nft.setPhase(MultiNFT.Phase.Phase1);

• Mint an NFT in Phase 1:

nft.mintFree(proof);

• Mint an NFT in Phase 2:

nft.mintWithDiscount(proof, signature);

• Mint an NFT in Phase 3:

nft.mintNFT();

• Claim Vested Tokens:

nft.claimVestedTokens();

Testing

The contract includes a comprehensive test suite written in Foundry. To run the tests:

forge test

Test Coverage

• Phased Minting:
  • Valid and invalid Merkle proofs.
  • Valid and invalid signatures.
• Vesting Functionality:
  • Linear vesting schedule.
  • Token withdrawal by the owner.
• Edge Cases:
  • Reentrancy attacks.
  • Invalid phases.

Security

The contract uses OpenZeppelin's ReentrancyGuard to prevent reentrancy attacks. Additionally, it ensures:

• Signatures cannot be reused.
• Merkle proofs are validated to prevent unauthorized minting.
• Only the owner can claim vested tokens.