HabboAPI AngularJS User Service

angular.module('app').service('UserService', function(AppConstants, $http, $q)
{
    var UserService = {};

    UserService.validate_username = function(user_name)
    {
        if(user_name == '' || null) return $q.reject('invalid_parameters');

        return $http.post(AppConstants.api + '/service/user/validate_username', {user_name: user_name})

        .then(function resolve(res)
        {
            return $q.resolve(null);
        },

        function reject(res)
        {
            return $q.reject((res.data.error == undefined || null) ? 'invalid_username' : res.data.error);
        });
    };

    UserService.validate_email = function(email_address)
    {
        if(email_address == '' || null) return $q.reject('invalid_parameters');

        return $http.post(AppConstants.api + '/service/user/validate_email', {email_address: email_address})

        .then(function resolve(res)
        {
            return $q.resolve(null);
        },

        function reject(res)
        {
            return $q.reject((res.data.error == undefined || null) ? 'invalid_email' : res.data.error);
        });
    };

    UserService.update_user = function(data)
    {
        if(data == '' || null) return $q.reject('invalid_parameters');

        return $http.post(AppConstants.api + '/service/user/update_user', {data: data})

        .then(function resolve(res)
        {
            if(res.data.user == undefined || null) return $q.reject('invalid_user');

            return $q.resolve(null);
        },

        function reject(res)
        {
            return $q.reject((res.data.error == undefined || null) ? 'invalid_user' : res.data.error);
        });
    };

    UserService.update_settings = function(data)
    {
        if(data == '' || null) return $q.reject('invalid_parameters');

        return $http.post(AppConstants.api + '/service/user/update_settings', {data: data})

        .then(function resolve(res)
        {
            return $q.resolve(null);
        },

        function reject(res)
        {
            return $q.reject((res.data.error == undefined || null) ? 'invalid_user' : res.data.error);
        });
    };

    UserService.update_password = function(new_password, password)
    {
        if(new_password == '' || null || password == '' || null) return $q.reject('invalid_parameters');

        return $http.post(AppConstants.api + '/service/user/update_password', {new_password: new_password, password: password})

        .then(function resolve(res)
        {
            return $q.resolve(null);
        },

        function reject(res)
        {
            return $q.reject((res.data.error == undefined || null) ? 'invalid_user' : res.data.error);
        });
    };

    UserService.update_email = function(new_email, password)
    {
        if(new_email == '' || null || password == '' || null) return $q.reject('invalid_parameters');

        return $http.post(AppConstants.api + '/service/user/update_email', {new_email: new_email, password: password})

        .then(function resolve(res)
        {
            return $q.resolve(null);
        },

        function reject(res)
        {
            return $q.reject((res.data.error == undefined || null) ? 'invalid_user' : res.data.error);
        });
    };

    UserService.add_user = function(user_name, user_email, user_pass)
    {
        if(user_name == '' || null || user_email == '' || null || user_pass == '' || null) return $q.reject('invalid_parameters');

        return $http.post(AppConstants.api + '/service/user/add_user', {user_name: user_name, user_email: user_email, user_pass: user_pass})

        .then(function resolve(res)
        {
            if(res.data.user == undefined || null) return $q.reject('invalid_user');

            return $q.resolve(res.data.user);
        },

        function reject(res)
        {
            return $q.reject((res.data.error == undefined || null) ? 'invalid_user' : res.data.error);
        });
    };

    return UserService;
});