models/controllers for FeelGoodTrader.com notification system

open_notification.rb

class OpenNotification < ActiveRecord::Base
  
  belongs_to :user
  belongs_to :listing
  
  validates_presence_of   :user_id
  validates_presence_of   :listing_id
  validates_uniqueness_of :listing_id, :scope => :user_id
  validate :a_user_cannot_get_a_notification_for_their_own_listing
  
  def self.new_open_notifications(user_id)
    @open_notifications = OpenNotification.find(
      :all,
      :conditions => ["user_id = ?", user_id]
    )
  end
  
  private
    def a_user_cannot_get_a_notification_for_their_own_listing
      unless user_id != listing.user_id
        errors.add("A user cannot receive a notification for their own listing.")
      end
    end
      
end

open_notifications_controller.rb

class OpenNotificationsController < ApplicationController
  
  before_filter :require_user
  before_filter :require_notification_author, :only => [:destroy]
  
  def ssl_allowed?
    true
  end
  
  def destroy
    open_notification = OpenNotification.find(params[:id])
    
    if open_notification  
      open_notification.destroy
    end
    
    redirect_back_or :root
  end
  
  private
    def require_notification_author
      unless current_user.id == OpenNotification.find(params[:id]).user_id
        flash[:error] = "You cannot delete another person's notification."
        redirect_back_or :root
      end
    end
  
end

search_notification.rb

class SearchNotification < ActiveRecord::Base
  
  belongs_to :user
  
  validates_presence_of   :user_id
  validates_presence_of   :query
  validates_uniqueness_of :query, :scope => :user_id
  
end

search_notification_controller.rb

class SearchNotificationsController < ApplicationController
  
  before_filter :require_user
  before_filter :require_notification_owner_or_admin, :only => [:edit, :destroy]

  def ssl_allowed?
    true
  end
  
  def create
    unless params[:search_notification][:query].strip.blank?
      @search_notification = SearchNotification.new(params[:search_notification])
      @search_notification.user = current_user
      @search_notification.query.strip!
      @search_notification.query.downcase!
    
      if @search_notification.save
        flash[:notice] = "You will now get notifications for '#{params[:search_notification][:query]}'"
        redirect_to edit_my_profile_users_path
      else
        if SearchNotification.find_by_query(params[:search_notification][:query])
          flash[:warning] = "You've already got a notification setup for that. You're good to go!"
        else
          flash[:error] = "An error occured"
        end
        redirect_back_or :root
      end
    else
      redirect_back_or :root
    end
  end
  
  def update
    @search_notification = SearchNotification.find(params[:id])
    
    if @search_notification.update_attributes(params[:search_notification])
      flash[:notice] = "Notification updated"
    else
      flash[:error] = "Error"
    end
    
    redirect_back_or :root
  end
  
  def destroy
    @search_notification = SearchNotification.find(params[:id])
    
    flash[:notice] = "You will no longer get new notifications for '#{@search_notification.query}'"
    @search_notification.delete
    redirect_back_or :root
  end
  
  private
    def require_notification_owner_or_admin
      unless current_user.id == SearchNotification.find(params[:id]).user_id || current_user.has_admin_rights
        flash[:error] = "You don't have access to that."
        redirect_back_or :root
      end
    end
  
end