Add SAFE certificate extension

src/storage/extensions/SAFEExtension.sol

@@ -0,0 +1,117 @@
+/*    .o.                                                                                             
+     .888.                                                                                            
+    .8"888.                                                                                           
+   .8' `888.                                                                                          
+  .88ooo8888.                                                                                         
+ .8'     `888.                                                                                        
+o88o     o8888o                                                                                       
+
+
+
+ooo        ooooo               .             ooooo                  ooooooo  ooooo                    
+`88.       .888'             .o8             `888'                   `8888    d8'                     
+ 888b     d'888   .ooooo.  .o888oo  .oooo.    888          .ooooo.     Y888..8P                        
+ 8 Y88. .P  888  d88' `88b   888   `P  )88b   888         d88' `88b     `8888'                        
+ 8  `888'   888  888ooo888   888    .oP"888   888         888ooo888    .8PY888.                       
+ 8    Y     888  888    .o   888 . d8(  888   888       o 888    .o   d8'  `888b                      
+o8o        o888o `Y8bod8P'   "888" `Y888""8o o888ooooood8 `Y8bod8P' o888o  o88888o                    
+
+
+
+  .oooooo.                .o8                            .oooooo.                                     
+ d8P'  `Y8b              "888                           d8P'  `Y8b                                    
+888          oooo    ooo  888oooo.   .ooooo.  oooo d8b 888           .ooooo.  oooo d8b oo.ooooo.      
+888           `88.  .8'   d88' `88b d88' `88b `888""8P 888          d88' `88b `888""8P  888' `88b     
+888            `88..8'    888   888 888ooo888  888     888          888   888  888      888   888     
+`88b    ooo     `888'     888   888 888    .o  888     `88b    ooo  888   888  888      888   888 .o. 
+ `Y8bood8P'      .8'      `Y8bod8P' `Y8bod8P' d888b     `Y8bood8P'  `Y8bod8P' d888b     888bod8P' Y8P 
+             .o..P'                                                                     888           
+             `Y8P'                                                                     o888o           
+_______________________________________________________________________________________________________
+
+All software, documentation and other files and information in this repository (collectively, the "Software")
+are copyright MetaLeX Labs, Inc., a Delaware corporation.
+
+All rights reserved.
+
+The Software is proprietary and shall not, in part or in whole, be used, copied, modified, merged, published, 
+distributed, transmitted, sublicensed, sold, or otherwise used in any form or by any means, electronic or
+mechanical, including photocopying, recording, or by any information storage and retrieval system, 
+except with the express prior written permission of the copyright holder.*/
+
+pragma solidity 0.8.28;
+
+import "@openzeppelin/contracts-upgradeable/proxy/utils/UUPSUpgradeable.sol";
+import "./ICertificateExtension.sol";
+import "../../libs/auth.sol";
+
+struct SAFEData {
+    string customProvisions; // an arbitrary string intended to insert any custom provision the parties agree upon
+}
+
+contract SAFEExtension is UUPSUpgradeable, ICertificateExtension, BorgAuthACL {
+    bytes32 public constant EXTENSION_TYPE = keccak256("SAFE");
+
+    //ofset to leave for future upgrades
+    uint256[30] private __gap;
+
+    function initialize(address _auth) external initializer {
+        __UUPSUpgradeable_init();
+        __BorgAuthACL_init(_auth);
+    }
+
+    function decodeExtensionData(bytes memory data) external view returns (SAFEData memory) {
+        return abi.decode(data, (SAFEData));
+    }
+
+    function encodeExtensionData(SAFEData memory data) external pure returns (bytes memory) {
+        return abi.encode(data);
+    }
+
+    function supportsExtensionType(bytes32 extensionType) external pure override returns (bool) {
+        return extensionType == EXTENSION_TYPE;
+    }
+
+    function getExtensionURI(bytes memory data) external view override returns (string memory) {
+        SAFEData memory decoded = abi.decode(data, (SAFEData));
+
+        string memory json = string(abi.encodePacked(
+            ', "SAFEDetails": {',
+            '"purchaseAmount": "', uint256ToString(decoded.purchaseAmount),
+            '", "postMoneyValuationCap": "', uint256ToString(decoded.postMoneyValuationCap),
+            '", "expirationTime": "', uint256ToString(decoded.expirationTime),
+            '", "governingJurisdiction": "', decoded.governingJurisdiction,
+            '", "disputeResolution": "', decoded.disputeResolution,
+            '"}'
+        ));
+
+        return json;
+    }
+
+    // Helper function to convert uint256 to string
+    function uint256ToString(uint256 _i) internal pure returns (string memory) {
+        if (_i == 0) {
+            return "0";
+        }
+        uint256 j = _i;
+        uint256 len;
+        while (j != 0) {
+            len++;
+            j /= 10;
+        }
+        bytes memory bstr = new bytes(len);
+        uint256 k = len;
+        while (_i != 0) {
+            k = k-1;
+            uint8 temp = uint8(48 + (_i % 10));
+            bytes1 b1 = bytes1(temp);
+            bstr[k] = b1;
+            _i /= 10;
+        }
+        return string(bstr);
+    }
+
+    function _authorizeUpgrade(
+        address newImplementation
+    ) internal virtual override onlyOwner {}
+}