Fix build errors and dependency conflicts in SEQICO smart contract project

README.md

@@ -13,7 +13,7 @@ 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 $3 minimum validation
 - Owner-only functions for token management and fund withdrawal
 - Automatic ETH refunds for overpayments
 - Event logging for all purchases
@@ -44,13 +44,21 @@ npx hardhat run scripts/deploy.js
 npx hardhat run scripts/deploy-DE.js
 ```
 
+4. Run tests:
+```bash
+npm test
+```
+
 ## Contract Functions
 
 ### SEQICO Contract
 - `buyWithETH(uint256 tokenAmount)`: Purchase tokens with ETH
 - `buyWithUSDT(uint256 tokenAmount)`: Purchase tokens with USDT
 - `buyWithUSDC(uint256 tokenAmount)`: Purchase tokens with USDC
 - `setSEQToken(address _seqToken)`: Update SEQ token address (owner only)
+- `setPricePerTokenETH(uint256 _pricePerTokenETH)`: Set ETH price per token (owner only, ≥$3)
+- `setPricePerTokenUSDT(uint256 _pricePerTokenUSDT)`: Set USDT price per token (owner only, ≥$3)
+- `setPricePerTokenUSDC(uint256 _pricePerTokenUSDC)`: Set USDC price per token (owner only, ≥$3)
 - `withdrawETH(address payable recipient)`: Withdraw collected ETH (owner only)
 - `withdrawERC20(address token, address recipient)`: Withdraw ERC20 tokens (owner only)
 

contracts/MockERC20.sol

@@ -0,0 +1,28 @@
+// SPDX-License-Identifier: MIT
+pragma solidity ^0.8.24;
+
+import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
+
+contract MockERC20 is ERC20 {
+    uint8 private _decimals;
+
+    constructor(
+        string memory name,
+        string memory symbol,
+        uint256 totalSupply
+    ) ERC20(name, symbol) {
+        // Determine decimals based on symbol for consistency with common tokens
+        if (keccak256(bytes(symbol)) == keccak256(bytes("USDT")) || 
+            keccak256(bytes(symbol)) == keccak256(bytes("USDC"))) {
+            _decimals = 6;
+        } else {
+            _decimals = 18;
+        }
+
+        _mint(msg.sender, totalSupply);
+    }
+
+    function decimals() public view virtual override returns (uint8) {
+        return _decimals;
+    }
+}

contracts/SEQICO.sol

@@ -13,6 +13,10 @@ contract SEQICO is Ownable {
     uint256 public pricePerTokenUSDT;
     uint256 public pricePerTokenUSDC;
 
+    // Minimum price constants (equivalent to $3 USD)
+    uint256 public constant MIN_PRICE_USD = 3 * 1e6; // $3 in 6 decimal format (USDT/USDC)
+    uint256 public constant MIN_PRICE_ETH = 0.001 ether; // Conservative minimum (~$3 when ETH > $3000)
+
     event TokensPurchased(address indexed buyer, uint256 amount, string payment);
 
     constructor(
@@ -26,6 +30,12 @@ contract SEQICO is Ownable {
         seqToken = IERC20(_seqToken);
         usdt = IERC20(_usdt);
         usdc = IERC20(_usdc);
+
+        // Validate minimum prices during deployment
+        require(_pricePerTokenETH >= MIN_PRICE_ETH, "Price must be greater than or equal to $3");
+        require(_pricePerTokenUSDT >= MIN_PRICE_USD, "Price must be greater than or equal to $3");
+        require(_pricePerTokenUSDC >= MIN_PRICE_USD, "Price must be greater than or equal to $3");
+
         pricePerTokenETH = _pricePerTokenETH;
         pricePerTokenUSDT = _pricePerTokenUSDT;
         pricePerTokenUSDC = _pricePerTokenUSDC;
@@ -35,9 +45,24 @@ contract SEQICO is Ownable {
         seqToken = IERC20(_seqToken);
     }
 
+    function setPricePerTokenETH(uint256 _pricePerTokenETH) external onlyOwner {
+        require(_pricePerTokenETH >= MIN_PRICE_ETH, "Price must be greater than or equal to $3");
+        pricePerTokenETH = _pricePerTokenETH;
+    }
+
+    function setPricePerTokenUSDT(uint256 _pricePerTokenUSDT) external onlyOwner {
+        require(_pricePerTokenUSDT >= MIN_PRICE_USD, "Price must be greater than or equal to $3");
+        pricePerTokenUSDT = _pricePerTokenUSDT;
+    }
+
+    function setPricePerTokenUSDC(uint256 _pricePerTokenUSDC) external onlyOwner {
+        require(_pricePerTokenUSDC >= MIN_PRICE_USD, "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;
+        uint256 requiredETH = pricePerTokenETH * tokenAmount / 1e18; // Properly account for token decimals
         require(msg.value >= requiredETH, "Insufficient ETH sent");
         require(seqToken.balanceOf(address(this)) >= tokenAmount, "Not enough SEQ tokens");
 

docs/TESTING_AND_DEBUGGING.md

@@ -0,0 +1,249 @@
+# SEQICO Smart Contract Testing and Debugging Guide
+
+This document provides comprehensive guidance on testing and debugging the SEQICO smart contract, specifically focusing on the $3 minimum price validation feature.
+
+## Overview
+
+The SEQICO contract implements strict $3 minimum price validation for all supported payment methods (ETH, USDT, USDC). This ensures that token prices never fall below a reasonable threshold, protecting both the project and investors.
+
+## Key Features
+
+### 1. Minimum Price Constants
+- `MIN_PRICE_USD`: 3,000,000 (represents $3.00 with 6 decimals for USDT/USDC)
+- `MIN_PRICE_ETH`: 0.001 ETH (conservative minimum representing ~$3 when ETH > $3000)
+
+### 2. Price Setting Functions
+All price setting functions enforce the $3 minimum:
+- `setPricePerTokenETH(uint256 _pricePerTokenETH)`
+- `setPricePerTokenUSDT(uint256 _pricePerTokenUSDT)`
+- `setPricePerTokenUSDC(uint256 _pricePerTokenUSDC)`
+
+### 3. Owner-Only Access Control
+Price setting functions can only be called by the contract owner, enforced by OpenZeppelin's `onlyOwner` modifier.
+
+## Testing
+
+### Running the Test Suite
+
+```bash
+# Run all tests
+npm test
+
+# Run specific test groups
+npx hardhat test --grep "Price Setting Functions"
+npx hardhat test --grep "Deployment"
+npx hardhat test --grep "Edge Cases"
+```
+
+### Test Coverage
+
+The test suite covers:
+
+1. **Deployment Validation**
+   - ✅ Valid prices above $3 minimum
+   - ❌ Rejection of prices below minimum for each currency
+
+2. **Price Setting Functions**
+   - ✅ Owner can set valid prices
+   - ❌ Non-owner cannot set prices (access control)
+   - ❌ Prices below minimum are rejected
+   - ✅ Prices exactly at minimum are accepted
+
+3. **Purchase Functions**
+   - ✅ Valid purchases with all payment methods
+   - ✅ Price validation is enforced during purchases
+
+4. **Edge Cases**
+   - ✅ Exactly $3 minimum prices
+   - ❌ One wei below minimum
+   - ✅ Very large prices without overflow
+
+5. **Constants Validation**
+   - ✅ Correct minimum price constants
+   - ✅ Constants remain unchanged throughout contract lifecycle
+
+### Understanding Test Results
+
+- ✅ **Green/Passing**: Feature works correctly
+- ❌ **Red/Failing**: Issue detected - investigate immediately
+- ⚠️ **Warning**: Unexpected behavior - review implementation
+
+## Debugging Tools
+
+### 1. Price Validation Verification Script
+
+Verify correct implementation of price-setting functions:
+
+```bash
+# Set contract address and run verification
+SEQICO_ADDRESS=0x... npx hardhat run scripts/verify-price-validation.js
+```
+
+**What it checks:**
+- Current price settings vs. minimums
+- Price setting function access controls
+- Validation of edge cases
+- Gas usage estimates
+
+### 2. Transaction Debugger
+
+Analyze failed transactions and common errors:
+
+```bash
+# Analyze specific transaction
+SEQICO_ADDRESS=0x... TX_HASH=0x... npx hardhat run scripts/debug-transactions.js
+
+# Simulate common error scenarios
+SEQICO_ADDRESS=0x... npx hardhat run scripts/debug-transactions.js
+
+# Generate debug report
+SEQICO_ADDRESS=0x... npx hardhat run scripts/debug-transactions.js --report
+```
+
+**Features:**
+- Transaction failure analysis
+- Revert reason extraction
+- Common error simulation
+- Purchase calculation validation
+
+## Common Error Messages and Solutions
+
+### 1. "Price must be greater than or equal to $3"
+
+**Cause**: Attempting to set a price below the minimum threshold.
+
+**Solutions:**
+- For ETH: Ensure price ≥ 0.001 ETH
+- For USDT/USDC: Ensure price ≥ 3,000,000 (6 decimals)
+
+**Example Fix:**
+```javascript
+// ❌ Wrong - below minimum
+await seqico.setPricePerTokenETH(ethers.parseEther("0.0001"));
+
+// ✅ Correct - above minimum
+await seqico.setPricePerTokenETH(ethers.parseEther("0.01"));
+```
+
+### 2. "Ownable: caller is not the owner"
+
+**Cause**: Non-owner attempting to call price setting functions.
+
+**Solutions:**
+- Use the owner's private key/account
+- Transfer ownership if needed
+- Verify correct contract address
+
+### 3. "Insufficient ETH sent"
+
+**Cause**: Buyer didn't send enough ETH for the requested tokens.
+
+**Calculation Check:**
+```javascript
+const tokenAmount = ethers.parseEther("1"); // 1 SEQ token
+const pricePerToken = await seqico.pricePerTokenETH(); // e.g., 0.01 ETH
+const requiredETH = pricePerToken * tokenAmount / ethers.parseEther("1");
+```
+
+### 4. "Not enough SEQ tokens"
+
+**Cause**: ICO contract doesn't have sufficient token balance.
+
+**Solutions:**
+- Transfer more SEQ tokens to the ICO contract
+- Check token allocation in deployment
+
+## Debugging Workflow
+
+### Step 1: Identify the Problem
+
+1. **Review transaction hash** if available
+2. **Check error message** for specific issue type
+3. **Verify contract state** using verification script
+
+### Step 2: Analyze Root Cause
+
+```bash
+# Run diagnostic checks
+SEQICO_ADDRESS=0x... npx hardhat run scripts/verify-price-validation.js
+
+# If transaction hash available
+SEQICO_ADDRESS=0x... TX_HASH=0x... npx hardhat run scripts/debug-transactions.js
+```
+
+### Step 3: Test Fix
+
+1. **Create test case** reproducing the issue
+2. **Implement fix** in contract or calling code
+3. **Run full test suite** to ensure no regressions
+
+```bash
+npm test
+```
+
+### Step 4: Deploy and Verify
+
+1. **Deploy updated contract** if needed
+2. **Run verification script** on new deployment
+3. **Monitor first transactions** for correct behavior
+
+## Best Practices
+
+### For Developers
+
+1. **Always test price validation** before deployment
+2. **Use verification script** after each deployment
+3. **Monitor transaction failures** and investigate immediately
+4. **Keep minimum price constants** reasonable but protective
+
+### For Users/Integration
+
+1. **Check current prices** before attempting purchases
+2. **Calculate required payments** correctly based on token decimals
+3. **Include sufficient gas** for transactions
+4. **Handle revert messages** gracefully in UI
+
+### For Monitoring
+
+1. **Set up alerts** for failed transactions
+2. **Regular health checks** using verification script
+3. **Monitor price changes** for reasonableness
+4. **Track gas usage** patterns
+
+## Automated Testing in CI/CD
+
+Add these commands to your CI/CD pipeline:
+
+```bash
+# Compile contracts
+npm run compile
+
+# Run full test suite
+npm test
+
+# Verify deployment (after deployment)
+SEQICO_ADDRESS=$DEPLOYED_ADDRESS npx hardhat run scripts/verify-price-validation.js
+```
+
+## Troubleshooting Checklist
+
+- [ ] Contract compiled successfully
+- [ ] All tests passing
+- [ ] Correct network configuration
+- [ ] Valid contract address
+- [ ] Owner account has sufficient gas
+- [ ] Price values use correct decimals
+- [ ] Token balances sufficient for operations
+
+## Support and Further Help
+
+For additional support:
+
+1. **Review test cases** in `test/SEQICO.test.js`
+2. **Check verification output** from debugging scripts
+3. **Examine recent transactions** on block explorer
+4. **Verify contract source code** on Etherscan
+
+---
+
+*This guide covers the essential aspects of testing and debugging the SEQICO contract's price validation system. Keep this document updated as the contract evolves.*

hardhat.config.js

@@ -1,4 +1,5 @@
-require("@nomicfoundation/hardhat-toolbox");
+import "@nomicfoundation/hardhat-ethers";
+import "@nomicfoundation/hardhat-chai-matchers";
 
 /** @type import('hardhat/config').HardhatUserConfig */
 const config = {
@@ -31,4 +32,4 @@ const config = {
   },
 };
 
-module.exports = config;
+export default config;