/// <summary>
/// Imports a public key to the wallet of the server node.
/// This allows for checking the balance of the public key.
/// </summary>
/// <param name="person"></param>
public static void ImportPublicKeyToWallet(Person person)
{
string chainName = WebConfigurationManager.AppSettings["ChainName"];
string nodeIp = WebConfigurationManager.AppSettings["NodeIp"];
MultiChainClient client = new MultiChainClient(chainName,nodeIp);
client.ImportAddress(person.PublicKey);
}
public Repository()
{
_client.DefaultRequestHeaders.Accept.Clear();
_client.DefaultRequestHeaders.Accept.Add(new System.Net.Http.Headers.MediaTypeWithQualityHeaderValue("application/json"));
_loginToken = (LoginSession)HttpContext.Current.Session ["token"];
_thisPerson = (Person)HttpContext.Current.Session ["person"];
//_client.DefaultRequestHeaders.Add("Authorization", Repository.Token);
}
/// <summary>
/// Gets a given person's (user) assets.
/// </summary>
/// <param name="person">person (user)</param>
/// <returns>AddressBalance array</returns>
public static AddressBalance[] GetPersonBalance(Person person)
{
string chainName = WebConfigurationManager.AppSettings["ChainName"];
string nodeIp = WebConfigurationManager.AppSettings["NodeIp"];
MultiChainClient client = new MultiChainClient(chainName,nodeIp);
var resp = client.GetAddressbalances (person.PublicKey);
return resp.Balances;
}
/// <summary>
/// Renews a LoginSession and replaces an already existing session.
/// </summary>
/// <param name="context">DataContext</param>
/// <param name="session">LoginSession</param>
/// <param name="person">Person (user)</param>
/// <returns>LoginSession</returns>
public static LoginSession RenewSession(DataContext context,LoginSession session,Person person)
{
session = new LoginSession (Guid.NewGuid ().ToString (), DateTime.Now);
if (person.LoginSession != null)
context.LoginSessions.Remove (person.LoginSession);
person.LoginSession = session;
context.SaveChanges();
return session;
}
public void LoginAttempt(string username, string password)
{
string publicKey = GetPublicKey ();
if (publicKey != "") {
Person person = new Person () { PublicKey = publicKey, Username = username, Password = password };
StringContent content = new StringContent (JsonConvert.SerializeObject (person));
content.Headers.ContentType = new System.Net.Http.Headers.MediaTypeHeaderValue ("application/json");
HttpResponseMessage response = _client.PostAsync ("Person/Login", content).Result;
if (!response.IsSuccessStatusCode) {
System.Web.HttpContext.Current.Response.Write ("<SCRIPT LANGUAGE=\"\"JavaScript\"\">alert(\"Login failed: " + response.StatusCode + ", make sure your login is correct and that your multichain node is the node associated with the account.\")</SCRIPT>");
} else {
var stream = response.Content.ReadAsStringAsync ().Result;
LoginSession session = JsonConvert.DeserializeObject<LoginSession> (stream);
_loginToken = session;
person.LoginSession = _loginToken;
person.LoginSessionToken = _loginToken.Token;
_thisPerson = person;
HttpContext.Current.Session ["token"] = _loginToken;
HttpContext.Current.Session ["person"] = _thisPerson;
}
} else {
System.Web.HttpContext.Current.Response.Write ("<SCRIPT LANGUAGE=\"\"JavaScript\"\">alert(\"Could not contact multichain node, make sure its running.\")</SCRIPT>");
}
}
public ActionResult Login(Person person)
{
using (DataContext context = new DataContext())
{
var match =
context.Persons.FirstOrDefault(x => x.PublicKey == person.PublicKey &&x.Username == person.Username && x.Password == person.Password);
if (match == null) {
if (!CreateNewPerson (person))
return new HttpStatusCodeResult((int)HttpStatusCode.BadRequest);
match =
context.Persons.FirstOrDefault(x => x.PublicKey == person.PublicKey &&x.Username == person.Username && x.Password == person.Password);
}
if (match.LoginSession != null)
return Content ( JsonConvert.SerializeObject(RenewSession(context,match.LoginSession,match)));
match.LoginSession = RenewSession(context,null,match);
context.SaveChanges();
return Content ( JsonConvert.SerializeObject(match.LoginSession));
}
}
/// <summary>
/// Creates a new user and returns a boolean (success).
/// </summary>
/// <param name="person">Person</param>
/// <returns>Success boolean</returns>
private bool CreateNewPerson(Person person)
{
using (DataContext context = new DataContext())
{
var match =
context.Persons.FirstOrDefault(x => x.PublicKey == person.PublicKey);
if (match != null)
return false;
if (String.IsNullOrEmpty(person.PublicKey) || String.IsNullOrEmpty(person.Username) || String.IsNullOrEmpty(person.Password))
return false;
person.LoginSession = null;
context.Persons.Add(person);
context.SaveChanges();
BlockChain.ImportPublicKeyToWallet (person);
return true;
}
}
/// <summary>
/// Returns the S and F from the BlockChain for a given person (user).
/// </summary>
/// <param name="person">Person (user)</param>
/// <returns>double array, first index is S amount, second index is F amount.</returns>
private double[] GetSFFromBlockChain(Person person)
{
var balances = BlockChain.GetPersonBalance (person);
var sBalance = balances.Where (x => x.name.StartsWith("S"));
var fBalance = balances.Where (x => x.name.StartsWith("F"));
var sAmount = sBalance != null ? sBalance.Sum(x=>x.qty) : 0;
var fAmount = fBalance != null ? fBalance.Sum(x=>x.qty) : 0;
return new double[] {sAmount, fAmount};
}
/// <summary>
/// Calculates the Bayesian reputation value for a given Person (user).
/// </summary>
/// <param name="person">Person (user)</param>
/// <returns>double reputation value</returns>
private double CalculateBayesianModelTrust(Person person)
{
double initialTrust = Convert.ToDouble(WebConfigurationManager.AppSettings["InitialTrust"]);
double trustProblabilityOfGoodPerson = Convert.ToDouble(WebConfigurationManager.AppSettings["TrustProblabilityOfGoodPerson"]);
double nonTrustProblabilityOfBadPerson = Convert.ToDouble(WebConfigurationManager.AppSettings["ŃonTrustProblabilityOfBadPerson"]);
double[] sfFloats = GetSFFromBlockChain(person);
double reputation = (initialTrust*Math.Pow(trustProblabilityOfGoodPerson, sfFloats[0])*
Math.Pow(1 - trustProblabilityOfGoodPerson, sfFloats[1]))/
(initialTrust*Math.Pow(trustProblabilityOfGoodPerson, sfFloats[0])*
Math.Pow(1 - trustProblabilityOfGoodPerson, sfFloats[1]) +
(1 - initialTrust)*Math.Pow(nonTrustProblabilityOfBadPerson, sfFloats[0])*
Math.Pow(1 - nonTrustProblabilityOfBadPerson, sfFloats[1]));
return reputation;
}
