Implement $3 minimum price validation for SEQICO smart contract

README.md

@@ -13,10 +13,14 @@ This project contains:
 
 ### SEQICO Contract
 - Buy SEQ tokens with ETH, USDT, or USDC
-- Configurable pricing for each payment method
+- Configurable pricing for each payment method with **minimum price validation**
 - Owner-only functions for token management and fund withdrawal
 - Automatic ETH refunds for overpayments
 - Event logging for all purchases
+- **Price validation**: Minimum price requirements enforced:
+  - ETH: minimum 3 ether (3 × 10¹⁸ wei)
+  - USDT: minimum 3,000,000 units (equivalent to $3 with 6 decimals)
+  - USDC: minimum 3,000,000 units (equivalent to $3 with 6 decimals)
 
 ### SEQToken Contract
 - Standard ERC20 token
@@ -50,18 +54,37 @@ npx hardhat run scripts/deploy-DE.js
 - `buyWithETH(uint256 tokenAmount)`: Purchase tokens with ETH
 - `buyWithUSDT(uint256 tokenAmount)`: Purchase tokens with USDT
 - `buyWithUSDC(uint256 tokenAmount)`: Purchase tokens with USDC
+- `setPricePerTokenETH(uint256 _pricePerTokenETH)`: Set ETH price per token (owner only, ≥ 3 ETH)
+- `setPricePerTokenUSDT(uint256 _pricePerTokenUSDT)`: Set USDT price per token (owner only, ≥ 3,000,000)
+- `setPricePerTokenUSDC(uint256 _pricePerTokenUSDC)`: Set USDC price per token (owner only, ≥ 3,000,000)
 - `setSEQToken(address _seqToken)`: Update SEQ token address (owner only)
 - `withdrawETH(address payable recipient)`: Withdraw collected ETH (owner only)
 - `withdrawERC20(address token, address recipient)`: Withdraw ERC20 tokens (owner only)
 
+## Price Validation Policy
+
+The SEQICO contract enforces minimum price requirements for SEQ tokens across all supported payment methods:
+
+- **ETH**: Minimum 3 ether (3,000,000,000,000,000,000 wei)
+- **USDT**: Minimum 3,000,000 units (equivalent to $3 with 6 decimals)
+- **USDC**: Minimum 3,000,000 units (equivalent to $3 with 6 decimals)
+
+This validation is applied in:
+- Contract deployment (constructor)
+- All price setter functions (`setPricePerTokenETH`, `setPricePerTokenUSDT`, `setPricePerTokenUSDC`)
+
+Any attempt to set a price below these minimums will result in a transaction revert with the message: **"Price must be greater than or equal to $3"**
+
 ## Configuration
 
 The deployment scripts include configurable parameters:
 - Owner address
 - USDT/USDC contract addresses
-- Token pricing for ETH, USDT, and USDC
+- Token pricing for ETH, USDT, and USDC (must meet minimum validation requirements)
 - Total supply (500,000 SEQ tokens)
 
+**Note**: When deploying, ensure all price parameters meet the minimum validation requirements, or the deployment will fail.
+
 ## License
 
 MIT

contracts/SEQICO.sol

@@ -22,7 +22,11 @@ contract SEQICO is Ownable {
         uint256 _pricePerTokenETH,
         uint256 _pricePerTokenUSDT,
         uint256 _pricePerTokenUSDC
-    ) {
+    ) Ownable(msg.sender) {
+        require(_pricePerTokenETH >= 3 ether, "Price must be greater than or equal to $3");
+        require(_pricePerTokenUSDT >= 3 * 10**6, "Price must be greater than or equal to $3");
+        require(_pricePerTokenUSDC >= 3 * 10**6, "Price must be greater than or equal to $3");
+
         seqToken = IERC20(_seqToken);
         usdt = IERC20(_usdt);
         usdc = IERC20(_usdc);
@@ -35,6 +39,21 @@ contract SEQICO is Ownable {
         seqToken = IERC20(_seqToken);
     }
 
+    function setPricePerTokenETH(uint256 _pricePerTokenETH) external onlyOwner {
+        require(_pricePerTokenETH >= 3 ether, "Price must be greater than or equal to $3");
+        pricePerTokenETH = _pricePerTokenETH;
+    }
+
+    function setPricePerTokenUSDT(uint256 _pricePerTokenUSDT) external onlyOwner {
+        require(_pricePerTokenUSDT >= 3 * 10**6, "Price must be greater than or equal to $3");
+        pricePerTokenUSDT = _pricePerTokenUSDT;
+    }
+
+    function setPricePerTokenUSDC(uint256 _pricePerTokenUSDC) external onlyOwner {
+        require(_pricePerTokenUSDC >= 3 * 10**6, "Price must be greater than or equal to $3");
+        pricePerTokenUSDC = _pricePerTokenUSDC;
+    }
+
     function buyWithETH(uint256 tokenAmount) external payable {
         require(tokenAmount > 0, "Amount must be greater than 0");
         uint256 requiredETH = pricePerTokenETH * tokenAmount;

contracts/SEQToken.sol

@@ -9,15 +9,12 @@ contract SEQToken is ERC20, Ownable {
         uint256 totalSupply,
         address owner,
         address icoContract
-    ) ERC20("SEQ Token", "SEQ") {
+    ) ERC20("SEQ Token", "SEQ") Ownable(owner) {
         // Mint 10% to owner, 90% to ICO contract
         uint256 ownerAmount = (totalSupply * 10) / 100;
         uint256 icoAmount = totalSupply - ownerAmount;
 
         _mint(owner, ownerAmount);
         _mint(icoContract, icoAmount);
-
-        // Transfer ownership to the specified owner
-        _transferOwnership(owner);
     }
 }

hardhat.config.js

@@ -1,3 +1,6 @@
+import "@nomicfoundation/hardhat-ethers";
+import "@nomicfoundation/hardhat-chai-matchers";
+
 /** @type import('hardhat/config').HardhatUserConfig */
 export default {
   solidity: "0.8.24"