{
    "secretKey": true,

    "clientList": {
        "paid": {...}
    },

    "users": {
        "$userID": {
            "profile": {...}
        }
    }

app.factory('RegisterFactory', ['AuthRefService', 'APP', '$q', 'appFunctions',
            function(AuthRefService, APP, $q, appFunctions){

    /**
     *  Precondition: A data structure of { 'secretKey': 'secretValue' },
     *  Postcondition: Returns a promise with the data at '/code' resolving with
     *      'secretValue' or null.
    */
    var checkCode = function(code){
        code = code.trim();
        var ref = new Firebase(APP.BASEURL);
        return ref.child(code).once('value');
    };

    /**
     *  Precondition: checkCode(code) resolves with true.
     *  Postcondition: A new user is created in Firebase and returns a
     *      promise resolving with userData (that only contains userData.uid and does not auth user) or error.
    */
    var createUser = function(credentials) {
        return AuthRefService.$createUser({
            email: credentials.email,
            password: credentials.password
        });
    };

    /**
     *  Precondition: checkCode(code) resolves with true.
     *  Postcondition: User is authenticated is and a promise resovles with authData or error
    */
    var authUser = function(credentials) {
        return AuthRefService.$authWithPassword({
            email: credentials.email,
            password: credentials.password
        });
    };

    /**
    *   Precondition: User is authenticated.
    *   Postcondition: Sets data at: /user/uid/profile and returns a
    *       promise resoloving w/o data if success, otherwise with error
    */
    var setProfile = function(authData, profile){
        var ref = new Firebase(APP.BASEURL + "users/" + authData.uid);
        return ref.child("profile").set(profile);
    };

    /**
    *   Precondition: User is authenticated.
    *   Postcondition: Sets data at: /clientList/paid and returns a
    *       promise resoloving w/o data if success, otherwise with error
    */
    var addToClientList = function(data, uid) {
        var now = appFunctions.dateToNum(new Date());  // yyyyMMdd
        var info = {
            first: data.profile.first,
            last: data.profile.last,
            email: data.credentials.email,
            dateJoined: now
        };

        var ref = new Firebase(APP.BASEURL + "clientList/paid");

        return ref.child(uid).set(info);
    };

    return {
        /**
        *   Precondition: user input, data, is complete
        *   Postcondition: A new user is created in database
        */
        register: function(data) {
            return $q(function(resolve, reject) {
                checkCode(data.credentials.code)
                .then(function(snapshot){
                    if(snapshot) {
                        createUser(data.credentials)
                        .then(function(userData) {
                            console.log("User create with id:", userData.uid);
                            authUser(data.credentials)
                            .then(function(authData) {
                                setProfile(authData, data.profile)
                                .then(function(resp) {

                                    // store new user in clientList index
                                    addToClientList(data, authData.uid)
                                    .then(function(resp) {
                                        // TODO: deal with this better
                                        // logout user, b/c I couldn't figure out a solution to smoothly get the new
                                        //   user to '/app' b/c of how app inits user upon login.
                                        AuthRefService.$unauth();
                                        resolve(true);
                                    }, function(err){
                                        if (typeof err !== "string") {
                                            err = "Error";
                                        }
                                        reject(err);
                                    });

                                }, function(err) {
                                    if (typeof err !== "string") {
                                        err = "Error";
                                    }
                                    reject(err);
                                });

                            }, function(err) {
                                if (typeof err !== "string") {
                                    err = "Error";
                                }
                                reject(err);
                            });

                        }, function(err) {
                            if (typeof err !== "string") {
                                err = "Error";
                            }
                            reject(err);
                        });
                    } else {
                        reject("Error");
                    }


                }, function(err){
                    reject("Invalid Registration Code");
                });
            });
        }
    };
}]);