Moving logic from controller to model in rails 3? - ruby-on-rails

Question

I've been building a contest application, and I can easily tell I've been putting wayyyy too much logic in the controller. How can I go about switch this type of logic to the model? (whats important here isn't the logic itself - its far from finished - I'm just trying to understand how to move it out of the controller).
Controller:
def create
#person = Person.new(params[:person])
#yournum = rand(100)
#day = Day.find_by_id(1)
#prereg = Prereg.find_by_email(#person.email)
if #preg != nil
#person.last_name = #prereg.name
end
if #day.number == 1
if #yournum <= 25
#person.prize_id = 2
elsif #yournum > 25 && #yournum <=50
#person.prize_id = 1
elsif #yournum > 51 && #yournum <=75
#person.prize_id = 3
elsif #yournum > 76 && #yournum <=100
#person.prize_id = 4
end
elsif #day.number == 2
if #yournum <= 25
#person.prize_id = 2
elsif #yournum > 25 && #yournum <=50
#person.prize_id = 1
elsif #yournum > 51 && #yournum <=75
#person.prize_id = 3
elsif #yournum > 76 && #yournum <=100
#person.prize_id = 4
end
elsif #day.number == 3
if #yournum <= 50
#person.prize_id = 2
elsif #yournum > 51 && #yournum <=90
#person.prize_id = 1
elsif #yournum > 91 && #yournum <= 95
#person.prize_id = 3
elsif #yournum > 96 && #yournum <=100
#person.prize_id = 4
end
end
#person.save
redirect_to #person
end
Model:
class Person < ActiveRecord::Base
belongs_to :prize
end
Thanks!
Elliot

Answer 1

Indeed, that's a pretty ugly controller. As you say, the solution is easy: move all the logic to the model:
def create
#person = Person.new(params[:person])
#person.set_price
if #person.save
redirect_to #person
else
flash[:error] = ...
render :action => 'new'
end
end
class Person
def set_price
# your logic here
end
end
Note that:
Controller: you need to check if #person was actually saved (maybe some validation failed).
Model: If a person has always to be assigned a price on creation, then use a callback (before_validation, for example). Otherwise, call it from the controller as shown the code above.

Answer 2

class PersonsController < ApplicationController
respond_to :html
def create
#person = Person.new(params[:person])
if #person.save
respond_with #person
else
flash[:error] = 'Render error'
render :action => :new
end
end
end
class Person
before_create :method_name
def method_name
#Put whatever you want to happen before creation here
end
end