Contract Actions

Buyback.sol is an upgradeable smart contract used to repurchase $FACTR tokens using USDC via Uniswap V3. It supports standard and custom buybacks, applies TWAP-based price checks, and locks acquired FACTR for 1 year before distribution to either predefined vaults or custom addresses.

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Dependencies

• OpenZeppelin Contracts:
  • Initializable
• Uniswap V3:
  • ISwapRouter
  • IUniswapV3Factory
  • IUniswapV3Pool
  • OracleLibrary
• Custom:
  • BuybackStorage.sol
  • IERC20

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Contract: Buyback

• Inherits:

  • BuybackStorage
  • Initializable

• Uses IERC20 and Uniswap V3 router for token swaps.

• All FACTR acquired through buybacks is subject to a 1-year lockup.

Functions

Initialization

• initialize: Sets up key contract parameters (e.g., vaults, tokens, routers, cooldowns). Called only once due to Initializable.

Standard Buyback

• buyback: Swaps contract-held USDC for FACTR. Can be called after cooldown. Verifies price using TWAP and handles slippage.
• buybackWithdraw: Distributes locked FACTR equally across 4 vaults after a 365-day lock.

Custom Buyback

• customBuyback: Allows anyone to perform a USDC-to-FACTR buyback with a custom distribution array. Enforces cooldown and TWAP constraints.
• customBuybackWithdraw: Distributes locked FACTR to predefined accounts based on basis points after 1 year.

Data Retrieval

• fetchActiveLocks: Returns all standard buybacks pending withdrawal.
• fetchActiveCustomLocks: Returns all custom buybacks pending withdrawal.

Utility (Internal)

• _sandwichProtectionCheck: Ensures current pool price doesn't deviate >1% from TWAP to prevent sandwich attacks.
• getOptimalTwapAmountThreshold: Calculates minimum expected output (FACTR) from swap, based on TWAP.
• calculateOptimalAmount: Iteratively finds the optimal USDC input amount for a swap that satisfies TWAP conditions.
• _executeSwap: Swaps USDC to FACTR using Uniswap router and defined path.
• estimateAmountOut: Returns average price quote from Uniswap based on historical ticks.

Admin Utility

• recoverERC20: Allows RECOVERER to recover non-FACTR and non-USDC tokens mistakenly sent to the contract.

Events

• BuybackCall: Emitted after a standard buyback is completed.
• CustomBuybackCall: Emitted after a custom buyback is completed.
• Withdraw: Emitted after locked FACTR from a standard buyback is distributed.
• CustomWithdraw: Emitted after locked FACTR from a custom buyback is distributed.
• ERC20Recovered: Emitted when admin recovers unrelated tokens from the contract.

Custom Errors / Validations

• Cooldown check via coolDownElapsed modifier.
• Buybacks require minimum 1000 USDC.
• Slippage and TWAP thresholds must be met or revert.
• Custom distribution arrays must sum to 10,000 bps.
• Withdrawals are only allowed after 365 days have passed.
• recoverERC20 rejects recovery of FACTR or USDC.

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Notes

• This contract ensures secure, automated buybacks that support token value via liquidity removal and delayed distribution.
• TWAP-based slippage validation minimizes the risk of manipulation and price impact.
• Custom buybacks make the contract suitable for DAO-driven or on-demand token redistribution.