Update SamoanStablecoin: Add AccessControl, ReentrancyGuard, Pausable…

…, and Chainlink integration

src/SamoanStablecoin.sol

@@ -2,12 +2,72 @@
 pragma solidity ^0.8.24;
 
 import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
-import "@openzeppelin/contracts/access/Ownable.sol";
+import "@openzeppelin/contracts/access/AccessControl.sol";
+import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
+import "@openzeppelin/contracts/security/Pausable.sol";
+import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";
 
-contract SamoanStablecoin is ERC20, Ownable {
-    constructor() ERC20("Samoan Stablecoin", "HAMO") Ownable(msg.sender) {
-        // Constructor logic here
+contract SamoanStablecoin is ERC20, AccessControl, ReentrancyGuard, Pausable {
+    bytes32 public constant MINTER_ROLE = keccak256("MINTER_ROLE");
+    bytes32 public constant BURNER_ROLE = keccak256("BURNER_ROLE");
+    bytes32 public constant PAUSER_ROLE = keccak256("PAUSER_ROLE");
+    bytes32 public constant PRICE_UPDATER_ROLE =
+        keccak256("PRICE_UPDATER_ROLE");
+
+    AggregatorV3Interface private priceFeed;
+    uint256 public lastUpdatedPrice;
+    uint256 public constant PRICE_PRECISION = 1e8;
+
+    event PriceUpdated(uint256 newPrice);
+
+    constructor(address _priceFeed) ERC20("Samoan Stablecoin", "SAMOA") {
+        _setupRole(DEFAULT_ADMIN_ROLE, msg.sender);
+        _setupRole(MINTER_ROLE, msg.sender);
+        _setupRole(BURNER_ROLE, msg.sender);
+        _setupRole(PAUSER_ROLE, msg.sender);
+        _setupRole(PRICE_UPDATER_ROLE, msg.sender);
+
+        priceFeed = AggregatorV3Interface(_priceFeed);
+        updatePrice();
     }
 
-    // Additional functions will be added here
+    function mint(
+        address to,
+        uint256 amount
+    ) external onlyRole(MINTER_ROLE) whenNotPaused nonReentrant {
+        _mint(to, amount);
+    }
+
+    function burn(
+        address from,
+        uint256 amount
+    ) external onlyRole(BURNER_ROLE) whenNotPaused nonReentrant {
+        _burn(from, amount);
+    }
+
+    function updatePrice() public onlyRole(PRICE_UPDATER_ROLE) whenNotPaused {
+        (, int256 price, , , ) = priceFeed.latestRoundData();
+        require(price > 0, "Invalid price");
+        lastUpdatedPrice = uint256(price);
+        emit PriceUpdated(lastUpdatedPrice);
+    }
+
+    function getLatestPrice() public view returns (uint256) {
+        return lastUpdatedPrice;
+    }
+
+    function pause() public onlyRole(PAUSER_ROLE) {
+        _pause();
+    }
+
+    function unpause() public onlyRole(PAUSER_ROLE) {
+        _unpause();
+    }
+
+    // Override required by Solidity
+    function supportsInterface(
+        bytes4 interfaceId
+    ) public view override(ERC20, AccessControl) returns (bool) {
+        return super.supportsInterface(interfaceId);
+    }
 }