Implement logging in via password

src/Signup.js

@@ -1,6 +1,7 @@
 "use strict";
 var MatrixClientPeg = require("./MatrixClientPeg");
 var dis = require("./dispatcher");
+var q = require("q");
 
 class Register {
 
@@ -43,6 +44,46 @@ class Login {
         var flowStep = this._flows[this._currentFlowIndex];
         return flowStep ? flowStep.type : null;
     }
+
+    loginViaPassword(username, pass) {
+        var self = this;
+        var isEmail = username.indexOf("@") > 0;
+        var loginParams = {
+            password: pass
+        };
+        if (isEmail) {
+            loginParams.medium = 'email';
+            loginParams.address = username;
+        } else {
+            loginParams.user = username;
+        }
+
+        return MatrixClientPeg.get().login('m.login.password', loginParams).then(function(data) {
+            return q({
+                homeserverUrl: self._hsUrl,
+                identityServerUrl: self._isUrl,
+                userId: data.user_id,
+                accessToken: data.access_token
+            });
+        }, function(error) {
+            if (error.httpStatus == 400 && loginParams.medium) {
+                error.friendlyText = (
+                    'This Home Server does not support login using email address.'
+                );
+            }
+            else if (error.httpStatus === 403) {
+                error.friendlyText = (
+                    'Incorrect username and/or password.'
+                );
+            }
+            else {
+                error.friendlyText = (
+                    'There was a problem logging in. (HTTP ' + error.httpStatus + ")"
+                );
+            }
+            throw error;
+        });
+    }
 }
 
 module.exports.Register = Register;