resolve ens

Shared/Ethereum/EthereumRPC.swift

@@ -1,6 +1,7 @@
 // Copyright © 2023 Tokenary. All rights reserved.
 
 import Foundation
+import WalletCore
 
 private struct RPCResponse: Codable {
     let id: Int
@@ -28,6 +29,31 @@ class EthereumRPC {
         request(method: "eth_gasPrice", params: [], rpcUrl: rpcUrl, completion: completion)
     }
     
+    func resolveENS(rpcUrl: String, for address: String, completion: @escaping (Result<String, Error>) -> Void) {
+        let reverseRecord = "\(address.lowercased().cleanHex).addr.reverse"
+        
+        var node = Data(repeating: 0, count: 32)
+        if !reverseRecord.isEmpty {
+            node = reverseRecord.split(separator: ".").reversed().reduce(node) { (currentNode, label) in
+                var node = currentNode
+                guard let data = label.data(using: .utf8) else { return Data() }
+                node.append(Hash.keccak256(data: data))
+                return Hash.keccak256(data: node)
+            }
+        }
+        
+        let nameHash = node.hexString
+        let method = "eth_call"
+        let params: [Any] = [
+            [
+                "to": "0x231b0Ee14048e9dCcD1d247744d114a4EB5E8E63",
+                "data": "0x691f3431" + String(repeating: "0", count: 64 - nameHash.count) + nameHash
+            ],
+            "latest"
+        ]
+        request(method: method, params: params, rpcUrl: rpcUrl, completion: completion)
+    }
+    
     func getBalance(rpcUrl: String, for address: String, completion: @escaping (Result<String, Error>) -> Void) {
         request(method: "eth_getBalance", params: [address, "pending"], rpcUrl: rpcUrl, completion: completion)
     }