I am trying to model a soccer tournament which consists of games and each game has two teams assigned:
The two models (Team and Game) that have a 2 : many relationship, i.e. 1 game has two teams. I modelled this with two has_many/has_one relationships to a model called TeamsGames. In there, I have an additional field "team_type" to keep track of whether it is a home or a guest team. This additional field is also the reason why I do not use a has_and_belongs_to_many relationship.
My first question is whether this design makes sense. I was thinking of using inheritance to differenciate between home and away teams, but because every team can be either one in different games, it does not work.
Anyway, I went ahead and created a form that allows you to enter game information (e.g. the date). The same form has two drop-down menus to choose the home and away team. The drop-downs are populated from the teams model. This approach seems to work fine except for the fact that I do not know how to validate the drop-down selections:
The validation needed is very simple: home and away team are required and must be different. The problem I have is that when I use standard, model based validation, I am checking against the database, but this is wrong. I should only compare the two drop-down boxes as these will update the database. I assume this has to be done in the controller somehow?
Any help would be appreciated.
Thanks, D.
Here is the code for the form, controller and my models:
[b]Edit Game Form[/b] [code=]<h2>Edit Game Details</h2>
<% form_tag :action => 'edit_game', :id => params[:id] do %> <%= error_messages_for :game %>
<p><label for="game_tournament_id">Tournament</label> <%= select :game, :tournament_id, @tournaments %></p>
<p><label for="game_name">Name</label> <%= text_field :game, :name %></p>
<p><label for="game_date">Date</label> <%= date_select :game, :date %></p>
<h2>Home and Guest Teams</h2> <p> <% for @teams_games in @game.teams_games %> <%= error_messages_for :teams_games %>
<% fields_for 'teams_games' do |f| %> <%= f.select :team_id, @teamslist %> <% end %> <% end %> </p>
<%= submit_tag 'Update' %> <%= link_to 'Cancel', :action => 'list_games', :id => @game.tournament %> <% end %>[/code] [b]The models[/b] [code=]class Team < ActiveRecord::Base
# t.column :name, :string, :null => false # t.column :founding_date, :date
has_many :teams_games, :class_name => 'TeamsGames' has_many :games, :through => :teams_games
validates_presence_of :name end
class Game < ActiveRecord::Base
# t.column :name, :string # t.column :date, :date # t.column :tournament_id, :integer, :null => false
belongs_to :tournament has_many :teams_games, :class_name => 'TeamsGames' has_many :teams, :through => :teams_games has_many :home_team, :through => :teams_games, :source => :team, :conditions => "teams_games.team_type = 'Home'", :limit => '1' has_many :guest_team, :through => :teams_games, :source => :team, :conditions => "teams_games.team_type = 'Guest'", :limit => '1'
validates_presence_of :tournament_id end
class TeamsGames < ActiveRecord::Base
# t.column :team_type, :string, :null => false # t.column :team_id, :integer, :null => false # t.column :game_id, :integer, :null => false
belongs_to :team belongs_to :game
validates_presence_of :team_id, :team_type
def self.get_team_types {:home => "Home", :guest => "Guest"} end end[/code] [b]The edit action[/b] [code=]def edit_game @tournaments = Tournament.find(:all, :order => 'name').map {|t| [t.name, t.id]} @game = Game.find(params[:id]) @teamslist = Team.find(:all, :order => 'name').map {|t| [t.name, t.id]}
if request.post? @game.attributes = params[:game] @game.teams_games.each { |t| t.attributes = params[:teams_games] [t.id.to_s] }
if @game.valid? && @game.teams_games.all?(&:valid?) @game.save! @game.teams_games.each(&:save!)
flash[:notice] = "#{@game.name} has been updated successfully" redirect_to :action => 'list_games', :id => @game.tournament end end end[/code]
