check isERC721 by checking erc165 ref

AlphaWallet/Settings/Types/Constants.swift

@@ -48,6 +48,9 @@ public struct Constants {
     public static let mainnetEtherscanContractDetailsWebPageURL = "https://etherscan.io/address/"
     public static let ropstenEtherscanContractDetailsWebPageURL = "https://ropsten.etherscan.io/address/"
     public static let rinkebyEtherscanContractDetailsWebPageURL = "https://rinkeby.etherscan.io/address/"
+    
+    //ERC specs
+    public static let erc721InterfaceHash = "0x80ac58cd"
 }
 
 public struct UnitConfiguration {

AlphaWallet/Tokens/Coordinators/GetIsERC721ContractCoordinator.swift

@@ -25,8 +25,33 @@ class GetIsERC721ContractCoordinator {
         let request = GetIsERC721Encode()
         web3.request(request: request) { result in
             switch result {
-            case .success:
+            case .success(let res):
+                let request2 = EtherServiceRequest(
+                    batch: BatchFactory().create(CallRequest(to: contract.description, data: res))
+                )
+                Session.send(request2) { [weak self] result2 in
+                    switch result2 {
+                    case .success(let is721):
+                        let request = GetIsERC721Decode(data: is721)
+                        self?.web3.request(request: request) { result in
+                            switch result {
+                            case .success(let isERC721):
+                                if isERC721 == "true" {
                                     completion(.success(true))
+                                }
+                                else {
+                                    completion(.success(false))
+                                }
+                            case .failure(let error):
+                                NSLog("getIsERC721Contract 3 error \(error)")
+                                completion(.failure(AnyError(error)))
+                            }
+                        }
+                    case .failure(let error):
+                        NSLog("getIsERC721Contract 2 error \(error)")
+                        completion(.failure(AnyError(error)))
+                    }
+                }
             case .failure(let error):
                 NSLog("getIsERC721 error \(error)")
                 completion(.failure(AnyError(error)))

AlphaWallet/Vendors/New Group/Commands/GetIsERC721Encode.swift

@@ -9,11 +9,9 @@ struct GetIsERC721Encode: Web3Request {
     typealias Response = String
 
     //Note: if this returns without error than it is ERC721 as non ERC721 contracts will not have this function
-    static let abi = "{ \"constant\": true, \"inputs\": [ { \"name\": \"_tokenId\", \"type\": \"uint256\" } ], \"name\": \"ownerOf\", \"outputs\": [ { \"name\": \"owner\", \"type\": \"address\" } ], \"payable\": false, \"stateMutability\": \"view\", \"type\": \"function\" }"
+    static let abi = "[ { \"constant\": true, \"inputs\": [ { \"name\": \"interfaceID\", \"type\": \"bytes4\" } ], \"name\": \"supportsInterface\", \"outputs\": [ { \"name\": \"\", \"type\": \"bool\" } ], \"payable\": false, \"stateMutability\": \"view\", \"type\": \"function\" } ]"
-  
-
     var type: Web3RequestType {
-        let run = "web3.eth.abi.encodeFunctionCall(\(GetIsERC721Encode.abi), [\(Constants.nullTicket)])"
+        let run = "web3.eth.abi.encodeFunctionCall(\(GetIsERC721Encode.abi), [\(Constants.erc721InterfaceHash)])"
         return .script(command: run)
     }
 }
@@ -24,7 +22,7 @@ struct GetIsERC721Decode: Web3Request {
     let data: String
 
     var type: Web3RequestType {
-        let run = "web3.eth.abi.decodeParameter('address', '\(data)')"
+        let run = "web3.eth.abi.decodeParameter('bool', '\(data)')"
         return .script(command: run)
     }
 }