Merge pull request #40 from bokobza/master

Wallet recovery work

Breeze.Documentation/ApiSpecification.md

@@ -167,12 +167,12 @@ Cannot check if the password is good or not. If the password is wrong it'll reco
 ## DELETE /wallet - Deletes the wallet
 Works as expected.
 
-## POST /wallet/account - Adds an account to the wallet
+## POST /wallet/account - Gets an unused account from the wallet
+This endpoint will get the first account containing no transaction or will create a new account.
 ### Parameters
 ```
 {
-    "walletName": "myFirstWallet",
-    "accountName": "account one",
+    "walletName": "myFirstWallet",    
     "password": "123456",
     "coinType": 105
 }

Breeze/src/Breeze.Api.Tests/Postman requests/Wallet.postman_collection.json

@@ -206,29 +206,9 @@
 				"description": "Gets all the wallets files stored in the default folder"
 			},
 			"response": []
-		},
-		{
-			"name": "New account for non-existant wallet fails",
-			"request": {
-				"url": "http://localhost:5000/api/v1/wallet/account",
-				"method": "POST",
-				"header": [
-					{
-						"key": "Content-Type",
-						"value": "application/json",
-						"description": ""
-					}
-				],
-				"body": {
-					"mode": "raw",
-					"raw": "{\n\t\"walletName\": \"myFirstWallet\",\n\t\"accountName\": \"account one\"\n}"
-				},
-				"description": ""
-			},
-			"response": []
-		},
+		},		
 		{
-			"name": "Create new account for wallet",
+			"name": "Get unused account in wallet",
 			"request": {
 				"url": "http://localhost:5000/api/v1/wallet/account",
 				"method": "POST",
@@ -241,7 +221,7 @@
 				],
 				"body": {
 					"mode": "raw",
-					"raw": "{\n\t\"walletName\": \"myFirstWallet\",\n\t\"accountName\": \"account one\",\n\t\"password\": \"123456\",\n\t\"coinType\": 105\n}"
+					"raw": "{\n\t\"walletName\": \"myFirstWallet\",\n\t\"password\": \"123456\",\n\t\"coinType\": 0\n}"
 				},
 				"description": ""
 			},
@@ -250,7 +230,7 @@
 		{
 			"name": "Get unused address in wallet",
 			"request": {
-				"url": "http://localhost:5000/api/v1/wallet/address?walletName=wallet1&accountName=account one&coinType=0",
+				"url": "http://localhost:5000/api/v1/wallet/address?walletName=wallet1&accountName=account 0&coinType=0",
 				"method": "GET",
 				"header": [
 					{

Breeze/src/Breeze.Wallet/Controllers/WalletController.cs

@@ -121,7 +121,7 @@ namespace Breeze.Wallet.Controllers
                 DirectoryInfo walletFolder = GetWalletFolder(request.FolderPath);
 
                 Wallet wallet = this.walletManager.RecoverWallet(request.Password, walletFolder.FullName, request.Name, request.Network, request.Mnemonic);
-
+         
                 // TODO give the tracker the date at which this wallet was originally created so that it can start syncing blocks for it
 
                 return this.Json(new WalletModel
@@ -355,7 +355,7 @@ namespace Breeze.Wallet.Controllers
         /// <returns>An account name.</returns>
         [Route("account")]
         [HttpPost]
-        public IActionResult CreateNewAccount([FromBody]CreateAccountModel request)
+        public IActionResult CreateNewAccount([FromBody]GetUnusedAccountModel request)
         {
             // checks the request is valid
             if (!this.ModelState.IsValid)
@@ -366,8 +366,8 @@ namespace Breeze.Wallet.Controllers
 
             try
             {
-                var result = this.walletManager.CreateNewAccount(request.WalletName, request.CoinType, request.AccountName, request.Password);
-                return this.Json(result);
+                var result = this.walletManager.GetUnusedAccount(request.WalletName, request.CoinType, request.Password);
+                return this.Json(result.Name);
             }
             catch (Exception e)
             {

Breeze/src/Breeze.Wallet/IWalletManager.cs

@@ -44,24 +44,49 @@ namespace Breeze.Wallet
         Wallet RecoverWallet(string password, string folderPath, string name, string network, string mnemonic, string passphrase = null, DateTimeOffset? creationTime = null);
 
         /// <summary>
-        /// Deleted a wallet.
+        /// Deletes a wallet.
         /// </summary>
         /// <param name="walletFilePath">The location of the wallet file.</param>        
         void DeleteWallet(string walletFilePath);
 
+        /// <summary>
+        /// Gets an account that contains no transactions.
+        /// </summary>
+        /// <param name="walletName">The name of the wallet from which to get an account.</param>
+        /// <param name="coinType">The type of coin for which to get an account.</param>
+        /// <param name="password">The password used to decrypt the private key.</param>
+        /// <remarks>
+        /// According to BIP44, an account at index (i) can only be created when the account
+        /// at index (i - 1) contains transactions.
+        /// </remarks>
+        /// <returns>An unused account.</returns>
+        HdAccount GetUnusedAccount(string walletName, CoinType coinType, string password);
+
+        /// <summary>
+        /// Gets an account that contains no transactions.
+        /// </summary>
+        /// <param name="wallet">The wallet from which to get an account.</param>
+        /// <param name="coinType">The type of coin for which to get an account.</param>
+        /// <param name="password">The password used to decrypt the private key.</param>
+        /// <remarks>
+        /// According to BIP44, an account at index (i) can only be created when the account
+        /// at index (i - 1) contains transactions.
+        /// </remarks>
+        /// <returns>An unused account.</returns>
+        HdAccount GetUnusedAccount(Wallet wallet, CoinType coinType, string password);
+        
         /// <summary>
         /// Creates a new account.
         /// </summary>
-        /// <param name="walletName">The name of the wallet in which this account will be created.</param>
-        /// <param name="coinType">the type of coin for which to create an account.</param>
-        /// <param name="accountName">The name by which this account will be identified.</param>
+        /// <param name="wallet">The wallet in which this account will be created.</param>
+        /// <param name="coinType">The type of coin for which to create an account.</param>
         /// <param name="password">The password used to decrypt the private key.</param>
         /// <remarks>
         /// According to BIP44, an account at index (i) can only be created when the account
         /// at index (i - 1) contains transactions.
         /// </remarks>
-        /// <returns>The name of the new account.</returns>
-        string CreateNewAccount(string walletName, CoinType coinType, string accountName, string password);
+        /// <returns>The new account.</returns>
+        HdAccount CreateNewAccount(Wallet wallet, CoinType coinType, string password);
 
         /// <summary>
         /// Gets an address that contains no transaction.
@@ -101,6 +126,6 @@ namespace Breeze.Wallet
         /// <param name="transaction">The transaction.</param>
         /// <param name="blockHeight">The height of the block this transaction came from. Null if it was not a transaction included in a block.</param>
         /// <param name="blockTime">The block time.</param>
-        void ProcessTransaction(CoinType coinType, NBitcoin.Transaction transaction, int? blockHeight = null, uint? blockTime = null);
+        void ProcessTransaction(CoinType coinType, NBitcoin.Transaction transaction, int? blockHeight = null, uint? blockTime = null);       
     }
 }

Breeze/src/Breeze.Wallet/Models/CreateAccountModel.cs

-using System;
-using System.Collections.Generic;
-using System.ComponentModel.DataAnnotations;
-using System.Text;
-
-namespace Breeze.Wallet.Models
-{
-    public class CreateAccountModel
-    {
-        /// <summary>
-        /// The name of the wallet in which to create the account.
-        /// </summary>
-        [Required]
-        public string WalletName { get; set; }
-
-        /// <summary>
-        /// The type of coin this account contains.
-        /// </summary>
-        [Required]
-        public CoinType CoinType { get; set; }
-
-        /// <summary>
-        /// The name of the account.
-        /// </summary>
-        [Required]
-        public string AccountName { get; set; }
-
-        /// <summary>
-        /// The password for this wallet.
-        /// </summary>
-        [Required]
-        public string Password { get; set; }
-
-
-    }
-}

Breeze/src/Breeze.Wallet/Models/RequestModels.cs

@@ -114,4 +114,25 @@ namespace Breeze.Wallet.Models
         [Required]
         public string AccountName { get; set; }
     }
+
+    public class GetUnusedAccountModel
+    {
+        /// <summary>
+        /// The name of the wallet in which to create the account.
+        /// </summary>
+        [Required]
+        public string WalletName { get; set; }
+
+        /// <summary>
+        /// The type of coin this account contains.
+        /// </summary>
+        [Required]
+        public CoinType CoinType { get; set; }
+
+        /// <summary>
+        /// The password for this wallet.
+        /// </summary>
+        [Required]
+        public string Password { get; set; }
+    }
 }

Breeze/src/Breeze.Wallet/Wallet.cs

 using System;
 using System.Collections.Generic;
+using System.Linq;
 using Breeze.Wallet.JsonConverters;
 using NBitcoin;
 using NBitcoin.JsonConverters;
@@ -80,6 +81,23 @@ namespace Breeze.Wallet
         /// </summary>
         [JsonProperty(PropertyName = "accounts")]
         public IEnumerable<HdAccount> Accounts { get; set; }
+
+        /// <summary>
+        /// Gets the first account that contains no transaction.
+        /// </summary>
+        /// <returns>An unused account</returns>
+        public HdAccount GetFirstUnusedAccount()
+        {
+            var unusedAccounts = this.Accounts.Where(acc => !acc.ExternalAddresses.Any() && !acc.InternalAddresses.Any()).ToList();
+            if (!unusedAccounts.Any())
+            {
+                return null;
+            }
+
+            // gets the unused account with the lowest index
+            var index = unusedAccounts.Min(a => a.Index);
+            return unusedAccounts.Single(a => a.Index == index);
+        }
     }
 
     /// <summary>
@@ -125,7 +143,6 @@ namespace Breeze.Wallet
         [JsonProperty(PropertyName = "name")]
         public string Name { get; set; }
 
-
         /// <summary>
         /// A path to the account as defined in BIP44.
         /// </summary>
@@ -156,6 +173,34 @@ namespace Breeze.Wallet
         /// </summary>
         [JsonProperty(PropertyName = "internalAddresses")]
         public IEnumerable<HdAddress> InternalAddresses { get; set; }
+
+        /// <summary>
+        /// Gets the type of coin this account is for.
+        /// </summary>
+        /// <returns>A <see cref="CoinType"/>.</returns>
+        public CoinType GetCoinType()
+        {
+            string[] pathElements = this.HdPath.Split('/');
+            int coinType = int.Parse(pathElements[2].Replace("'", string.Empty));
+            return (CoinType)coinType;
+        }
+
+        /// <summary>
+        /// Gets the first receiving address that contains no transaction.
+        /// </summary>
+        /// <returns>An unused address</returns>
+        public HdAddress GetFirstUnusedExternalAddress()
+        {
+            var unusedAddresses = this.ExternalAddresses.Where(acc => !acc.Transactions.Any()).ToList();
+            if (!unusedAddresses.Any())
+            {
+                return null;
+            }
+
+            // gets the unused address with the lowest index
+            var index = unusedAddresses.Min(a => a.Index);
+            return unusedAddresses.Single(a => a.Index == index);
+        }
     }
 
     /// <summary>

Breeze/src/Breeze.Wallet/WalletManager.cs

@@ -18,10 +18,14 @@ namespace Breeze.Wallet
     {
         public List<Wallet> Wallets { get; }
 
-        public HashSet<Script> PubKeys { get; }
+        public HashSet<Script> PubKeys { get; set; }
 
         public HashSet<TransactionDetails> TrackedTransactions { get; }
 
+        private const int UnusedAddressesBuffer = 20;
+
+        private const int WalletRecoveryAccountsCreationCount = 3;
+
         public WalletManager()
         {
             this.Wallets = new List<Wallet>();
@@ -53,7 +57,6 @@ namespace Breeze.Wallet
             ExtKey extendedKey = mnemonic.DeriveExtKey(passphrase);
 
             // create a wallet file 
-
             Wallet wallet = this.GenerateWalletFile(password, folderPath, name, WalletHelpers.GetNetwork(network), extendedKey);
 
             this.Load(wallet);
@@ -84,15 +87,28 @@ namespace Breeze.Wallet
             // generate the root seed used to generate keys
             ExtKey extendedKey = (new Mnemonic(mnemonic)).DeriveExtKey(passphrase);
 
+            Network coinNetwork = WalletHelpers.GetNetwork(network);
+
             // create a wallet file 
-            Wallet wallet = this.GenerateWalletFile(password, folderPath, name, WalletHelpers.GetNetwork(network), extendedKey, creationTime);
+            Wallet wallet = this.GenerateWalletFile(password, folderPath, name, coinNetwork, extendedKey, creationTime);
 
+            // generate multiple accounts and addresses from the get-go
+            for (int i = 0; i < WalletRecoveryAccountsCreationCount; i++)
+            {
+                HdAccount account = CreateNewAccount(wallet, CoinType.Bitcoin, password);
+                this.CreateAddressesInAccount(account, coinNetwork, UnusedAddressesBuffer);
+                this.CreateAddressesInAccount(account, coinNetwork, UnusedAddressesBuffer, true);
+            }
+
+            // save the changes to the file and add addresses to be tracked
+            this.SaveToFile(wallet);
+            this.PubKeys = this.LoadKeys(CoinType.Bitcoin);
             this.Load(wallet);
             return wallet;
         }
 
         /// <inheritdoc />
-        public string CreateNewAccount(string walletName, CoinType coinType, string accountName, string password)
+        public HdAccount GetUnusedAccount(string walletName, CoinType coinType, string password)
         {
             Wallet wallet = this.Wallets.SingleOrDefault(w => w.Name == walletName);
             if (wallet == null)
@@ -100,53 +116,69 @@ namespace Breeze.Wallet
                 throw new Exception($"No wallet with name {walletName} could be found.");
             }
 
-            // get the accounts for this type of coin
-            var accounts = wallet.AccountsRoot.Single(a => a.CoinType == coinType).Accounts.ToList();
-            int newAccountIndex = 0;
+            return this.GetUnusedAccount(wallet, coinType, password);
+        }
 
-            // validate account creation
-            if (accounts.Any())
+        /// <inheritdoc />
+        public HdAccount GetUnusedAccount(Wallet wallet, CoinType coinType, string password)
+        {
+            // get the accounts root for this type of coin
+            var accountsRoot = wallet.AccountsRoot.Single(a => a.CoinType == coinType);
+
+            // check if an unused account exists
+            if (accountsRoot.Accounts.Any())
             {
-                // check account with same name doesn't already exists
-                if (accounts.Any(a => a.Name == accountName))
+                // gets an unused account
+                var firstUnusedAccount = accountsRoot.GetFirstUnusedAccount();
+                if (firstUnusedAccount != null)
                 {
-                    throw new Exception($"Account with name '{accountName}' already exists in '{walletName}'.");
+                    return firstUnusedAccount;
                 }
+            }
 
-                // check account at index i - 1 contains transactions.
-                int lastAccountIndex = accounts.Max(a => a.Index);
-                HdAccount previousAccount = accounts.Single(a => a.Index == lastAccountIndex);
-                if (!previousAccount.ExternalAddresses.Any(addresses => addresses.Transactions.Any()) && !previousAccount.InternalAddresses.Any(addresses => addresses.Transactions.Any()))
-                {
-                    throw new Exception($"Cannot create new account '{accountName}' in '{walletName}' if the previous account '{previousAccount.Name}' has not been used.");
-                }
+            // all accounts contain transactions, create a new one
+            var newAccount = this.CreateNewAccount(wallet, coinType, password);
+
+            // save the changes to the file
+            this.SaveToFile(wallet);
+            return newAccount;
+        }
 
-                newAccountIndex = lastAccountIndex + 1;
+        /// <inheritdoc />
+        public HdAccount CreateNewAccount(Wallet wallet, CoinType coinType, string password)
+        {
+            // get the accounts for this type of coin
+            var accounts = wallet.AccountsRoot.Single(a => a.CoinType == coinType).Accounts.ToList();
+
+            int newAccountIndex = 0;
+            if (accounts.Any())
+            {
+                newAccountIndex = accounts.Max(a => a.Index) + 1;
             }
 
             // get the extended pub key used to generate addresses for this account
             var privateKey = Key.Parse(wallet.EncryptedSeed, password, wallet.Network);
             var seedExtKey = new ExtKey(privateKey, wallet.ChainCode);
-            var accountHdPath = $"m/44'/{(int) coinType}'/{newAccountIndex}'";
+            var accountHdPath = $"m/44'/{(int)coinType}'/{newAccountIndex}'";
             KeyPath keyPath = new KeyPath(accountHdPath);
             ExtKey accountExtKey = seedExtKey.Derive(keyPath);
             ExtPubKey accountExtPubKey = accountExtKey.Neuter();
 
-            accounts.Add(new HdAccount
+            var newAccount = new HdAccount
             {
                 Index = newAccountIndex,
                 ExtendedPubKey = accountExtPubKey.ToString(wallet.Network),
                 ExternalAddresses = new List<HdAddress>(),
                 InternalAddresses = new List<HdAddress>(),
-                Name = accountName,
+                Name = $"account {newAccountIndex}",
                 HdPath = accountHdPath,
                 CreationTime = DateTimeOffset.Now
-            });
+            };
 
+            accounts.Add(newAccount);
             wallet.AccountsRoot.Single(a => a.CoinType == coinType).Accounts = accounts;
-            this.SaveToFile(wallet);
 
-            return accountName;
+            return newAccount;
         }
 
         /// <inheritdoc />
@@ -165,42 +197,78 @@ namespace Breeze.Wallet
                 throw new Exception($"No account with name {accountName} could be found.");
             }
 
-            int newAddressIndex = 0;
-
             // validate address creation
             if (account.ExternalAddresses.Any())
             {
                 // check last created address contains transactions.
-                int lastAddressIndex = account.ExternalAddresses.Max(a => a.Index);
-                var lastAddress = account.ExternalAddresses.SingleOrDefault(a => a.Index == lastAddressIndex);
-                if (lastAddress != null && !lastAddress.Transactions.Any())
+                var firstUnusedExternalAddress = account.GetFirstUnusedExternalAddress();
+                if (firstUnusedExternalAddress != null)
                 {
-                    return lastAddress.Address;
+                    return firstUnusedExternalAddress.Address;
                 }
-
-                newAddressIndex = lastAddressIndex + 1;
             }
 
-            // generate new receiving address
-            BitcoinPubKeyAddress address = this.GenerateAddress(account.ExtendedPubKey, newAddressIndex, false, wallet.Network);
-
-            // add address details
-            account.ExternalAddresses = account.ExternalAddresses.Concat(new[] {new HdAddress
-            {
-                Index = newAddressIndex,
-                HdPath = CreateBip44Path(coinType, account.Index, newAddressIndex, false),
-                ScriptPubKey = address.ScriptPubKey,
-                Address = address.ToString(),
-                Transactions = new List<TransactionData>(),
-                CreationTime = DateTimeOffset.Now
-            }});
+            // creates an address
+            this.CreateAddressesInAccount(account, wallet.Network, 1);
 
             // persists the address to the wallet file
             this.SaveToFile(wallet);
 
             // adds the address to the list of tracked addresses
-            this.PubKeys.Add(address.ScriptPubKey);
-            return address.ToString();
+            this.PubKeys = this.LoadKeys(coinType);
+            return account.GetFirstUnusedExternalAddress().Address;
+        }
+
+        /// <summary>
+        /// Creates a number of addresses in the provided account.
+        /// </summary>
+        /// <param name="account">The account.</param>
+        /// <param name="network">The network.</param>
+        /// <param name="addressesQuantity">The number of addresses to create.</param>
+        /// <param name="isChange">Whether the addresses added are change (internal) addresses or receiving (external) addresses.</param>
+        /// <returns>A list of addresses in Base58.</returns>
+        private List<string> CreateAddressesInAccount(HdAccount account, Network network, int addressesQuantity, bool isChange = false)
+        {
+            List<string> addressesCreated = new List<string>();
+
+            var addresses = isChange ? account.InternalAddresses : account.ExternalAddresses;
+
+            // gets the index of the last address with transactions
+            int firstNewAddressIndex = 0;
+            if (addresses.Any())
+            {
+                firstNewAddressIndex = addresses.Max(add => add.Index) + 1;
+            }
+
+            for (int i = firstNewAddressIndex; i < firstNewAddressIndex + addressesQuantity; i++)
+            {
+                // generate new receiving address
+                BitcoinPubKeyAddress address = this.GenerateAddress(account.ExtendedPubKey, i, false, network);
+
+                // add address details
+                addresses = addresses.Concat(new[] {new HdAddress
+                {
+                    Index = i,
+                    HdPath = CreateBip44Path(account.GetCoinType(), account.Index, i, isChange),
+                    ScriptPubKey = address.ScriptPubKey,
+                    Address = address.ToString(),
+                    Transactions = new List<TransactionData>(),
+                    CreationTime = DateTimeOffset.Now
+                }});
+
+                addressesCreated.Add(address.ToString());
+            }
+
+            if (isChange)
+            {
+                account.InternalAddresses = addresses;
+            }
+            else
+            {
+                account.ExternalAddresses = addresses;
+            }
+
+            return addressesCreated;
         }
 
         public WalletGeneralInfoModel GetGeneralInfo(string name)
@@ -485,7 +553,7 @@ namespace Breeze.Wallet
                 SelectMany(a => a.ExternalAddresses).
                 Select(s => s.ScriptPubKey));
             // uncomment the following for testing on a random address 
-             // Select(t => (new BitcoinPubKeyAddress(t.Address, Network.Main)).ScriptPubKey));
+            //Select(t => (new BitcoinPubKeyAddress(t.Address, Network.Main)).ScriptPubKey));
         }
 
         /// <summary>