Showing errors in the modal rails - ruby-on-rails

Question

I'm very frustrated because I've been working on it for days and I haven't found a solution yet.
I have a Visit.rb model and, beyond the common validations, I have two more validations through two methods of mine (visit's start date cannot be prior to end one and there's no possibility to have two visits having the same start date, end date and visitor_id).
I need to show these errors set by me in the modal I'm giving to register a visit, but until now I've never had success.
In fact every time this error occurs: ArgumentError in VisitsController#create - First argument in form cannot contain nil or be empty
Here what I've done until now is...
Visit.rb
class Visit < ActiveRecord::Base
belongs_to :employee
belongs_to :visitor
default_scope -> { order(:created_at) }
validates :from, presence: true, uniqueness: { scope: [:to, :visitor_id] }
validates :to, presence: true
validates :visitor_id, presence: true
validates :employee_id, presence: true
validate :valid_date_range_required
validate :visit_uniqueness
def valid_date_range_required
if (from && to) && (to < from)
errors[:base] << "Visit's end date cannot be prior to the start one."
end
end
def visit_uniqueness
if Visit.find_by(from: :from, to: :to, visitor_id: :visitor_id)
errors[:base] << "A visit with the same start date, end date and visitor already exists."
end
end
end
visits_controller.rb
class VisitsController < ApplicationController
before_action :logged_in_employee, only: [:create, :destroy]
before_action :correct_employee, only: [:destroy, :update ]
def create
#visit = current_employee.visits.build(visit_params)
if #visit.save
flash[:success] = "Visit added"
redirect_to employee_path(session[:employee_id], :act => 'guestsVisits')
else
#visits = current_employee.visits.all
#employee = current_employee
render 'employees/guestsVisits'
end
end
private
def visit_params
params.require(:visit).permit(:from, :to, :visitor_id, :employee_id)
end
def correct_employee
#visit = current_employee.visits.find_by(id: params[:id])
redirect_to root_url if #visit.nil?
end
end
guestsVisits.rb (my view)
<div class="jumbotron3 text-center">
<div class="row">
<h1>Guests Visits</h1>
<hr>
<%=render :partial =>"layouts/sidebar"%>
<div class="panel3">
<div class="panel-body">
<!-- Modal for Visit -->
<% if logged_in? %>
<%=render :partial =>"shared/error_messages"%>
<a class="btn icon-btn btn-success pos" data-toggle="modal" data-target="#visitModal">
<span class="glyphicon btn-glyphicon glyphicon-plus img-circle text-success"></span>
Add a visit
</a>
<div id="visitModal" class="modal fade" role="dialog">
<div class="modal-dialog">
<div class="modal-content">
<div class="modal-header">
<button type="button" class="close" data-dismiss="modal">×</button>
<h4 class="modal-title">Add Visit</h4>
</div>
<div class="modal-body">
<%= form_for(#visit) do |f| %>
<%= f.label :start_date %>
<%= f.date_field :from, class: 'form-control',:value => (f.object.from.strftime('%m/%d/%Y') if f.object.from) %>
<%= errors_for #visit, :from %><%if #visit.errors.any?%><br><%end%>
<br>
<%= f.label :end_date %>
<%= f.date_field :to, class: 'form-control',:value => (f.object.to.strftime('%m/%d/%Y') if f.object.to) %>
<%= errors_for #visit, :to %><%if #visit.errors.any?%><br><%end%>
<br>
<%= f.label :Visitor %>
<%= f.collection_select :visitor_id, Visitor.all, :id, :full_name, { :class=> "form-control", :include_blank => ''}%>
<%= errors_for #visit, :visitor_id %><%if #visit.errors.any?%><br><%end%>
<br>
<%= f.submit "Add visit", class: "btn btn-primary btn-color" %>
<% end %>
</div>
<div class="modal-footer">
<button type="button" class="btn btn-info" data-dismiss="modal">Close</button>
</div>
</div>
</div>
</div>
<% end %>
</div>
</div>
</div>
</div>
I tried to use two different versions of error_messages.rb
error_messages.rb (1)
<% if #visit && #visit.errors.any? %>
<div id="error_explanation">
<div class="alert alert-danger">
×
The form contains <%= pluralize(#visit.errors.count, "error") %>.Open the modal for more details
</div>
</div>
<% end %>
error_messages.rb (2)
<% if #visit.errors.any? %>
<ul class="errors">
<% #visit.errors.full_messages.each do |msg| %>
<li><%= msg %></li>
<% end %>
</ul>
<% end %>
I hope someone can help me because I don't understand how to figure it out.
Thank you a lot.
EDIT:
class Employee < ActiveRecord::Base
before_save { self.email = email.downcase }
before_create :confirmation_token
VALID_EMAIL_REGEX = /\A[\w+\-.]+#[a-z\d\-.]+\.[a-z]+\z/i
has_many :macaddresss, dependent: :destroy
has_many :visits, dependent: :destroy
has_many :visitors, dependent: :destroy
#Validations
validates :name, presence: true , length: { maximum:20 , minimum: 2 }
validates :lastname, presence: true, length: { maximum:20 , minimum: 2 }
validates :gender, presence: true
validates :dateofbirth, presence: true
validates :birth_country, presence: true
validates :birth_place, presence: true, length: { maximum:60}
validates :contry_of_residence, presence: true
validates :city_of_residence, presence: true, length: { maximum:60 }
validates :address, presence: true, length: { maximum:60 , minimum: 7 }
validates :email, presence: true, length: { maximum:243 } ,format: { with: VALID_EMAIL_REGEX }, uniqueness: { case_sensitive: false }
validates :password, length: { minimum: 6 }
validates :terms_of_service, acceptance: { message: 'accept terms and conditions' }
[...]
has_secure_password
def Employee.digest(string)
cost = ActiveModel::SecurePassword.min_cost ? BCrypt::Engine::MIN_COST :
BCrypt::Engine.cost
BCrypt::Password.create(string, cost: cost)
end
end
session_helper.rb
def current_employee
#current_employee ||= Employee.find_by(id: session[:employee_id])
end
EDIT2:
employees_controller.rb
class EmployeesController < ApplicationController
def show
if logged_in?
#employee = Employee.find(params[:id])
#indirizzimac = current_employee.indirizzimacs.new
#visitor = current_employee.visitors.new
#visit = current_employee.visits.new
#visits = current_employee.visits.all
if params[:act]=='myData'
render 'myData'
elsif params[:act]=='myNetwork'
render 'myData'
elsif params[:act]=='temporaryUsers'
render 'temporaryUsers'
elsif params[:act]=='guestsVisits'
render 'guestsVisits'
elsif params[:act]=='myAccount'
render 'myAccount'
else
render 'show'
end
else
render 'static_pages/errorPage'
end
end
end

Answer 1

From what i can see if creating visit fails you instantiate #visits and #employee instance variables then rendering 'employees/guestsVisits' its view you use #visit which i think it doesn't exist inside empleyees controller
So add it ad
def guestsVisits
#visit = current_employee.visits.build
end