require File.expand_path(File.dirname(__FILE__) + '/../spec_helper')

include Fathom

describe Node do
  it "should take an options hash to instantiate" do
    lambda{Node.new(:any_value => true)}.should_not raise_error
  end
  
  it "should take an optional name parameter" do
    node = Node.new(:name => "My Name")
    node.name.should eql("My Name")
  end
  
  it "should take an optional distribution parameter" do
    node = Node.new(:distribution => Fathom::Distributions::Gaussian)
    node.distribution.should eql(Fathom::Distributions::Gaussian)
  end
  
  it "should default to the standard distribution" do
    node = Node.new
    node.distribution.should eql(Fathom::Distributions::Gaussian)
  end
  
  it "should be able to take a symbol and find the appropriate distribution" do
    node = Node.new(:distribution => :gaussian)
    node.distribution.should eql(Fathom::Distributions::Gaussian)
  end
  
  it "should take an optional description" do
    node = Node.new(:description => "some description")
    node.description.should eql('some description')
  end
  
  it "should take an optional values parameter" do
    node = Node.new(:values => [1,2,3])
    node.values.should eql([1,2,3])
  end
  
  it "should provide name_sym, if a name is defined" do
    node = Node.new(:name => "Some name")
    node.name_sym.should eql(:some_name)
  end
  
  it "should change dashes to underscores for name_sym" do
    node = Node.new(:name => "Some-name")
    node.name_sym.should eql(:some_name)
  end
  
  it "should take an optional parents list" do
    n1 = Node.new
    n2 = Node.new(:parents => [n1])
    n2.parents.should eql([n1])
  end
  
  it "should allow a single node as a parent or parents and turn it into an array" do
    n1 = Node.new
    n2 = Node.new(:parents => n1)
    n2.parents.should eql([n1])
    n2 = Node.new(:parent => n1)
    n2.parents.should eql([n1])
  end
  
  it "should create an empty list of parents by default" do
    n1 = Node.new
    n1.parents.should eql([])
  end
  
  it "should be able to add a parent" do
    n1, n2 = Node.new, Node.new
    n3 = Node.new(:parent => n2)
    n3.add_parent(n1)
    n3.parents.should eql([n2, n1])
  end
  
  it "should register the receiving node when adding a parent" do
    n1 = Node.new
    n1.should_receive(:register_child).and_return(true)
    n2 = Node.new(:parent => n1)

    n1 = Node.new
    n1.should_receive(:register_child).and_return(true)
    n2 = Node.new
    n2.add_parent(n1)
  end

  it "should not allow a parent to be registered if it is not a child of the other node" do
    n1 = Node.new
    n2 = Node.new
    lambda{n2.register_parent(n1)}.should raise_error
  end

  it "should take an optional children list" do
    n1 = Node.new
    n2 = Node.new(:children => [n1])
    n2.children.should eql([n1])
  end
  
  it "should allow a single node as a child or children and turn it into an array" do
    n1 = Node.new
    n2 = Node.new(:children => n1)
    n2.children.should eql([n1])
    n2 = Node.new(:child => n1)
    n2.children.should eql([n1])
  end
  
  it "should create an empty list of children by default" do
    n1 = Node.new
    n1.children.should eql([])
  end
  
  it "should register the receiving node when adding a child" do
    n1 = Node.new
    n1.should_receive(:register_parent).and_return(true)
    n2 = Node.new(:child => n1)

    n1 = Node.new
    n1.should_receive(:register_parent).and_return(true)
    n2 = Node.new
    n2.add_child(n1)
  end
  
  it "should not allow a child to be registered if it is not a parent of the other node" do
    n1 = Node.new
    n2 = Node.new
    lambda{n2.register_child(n1)}.should raise_error
  end
  
  it "should define an accessor method for the child node when added" do
    n1 = Node.new(:name => 'n1')
    n2 = Node.new :name => 'n2', :child => n1
    n2.n1.should eql(n1)
    n1.should_not respond_to(:n1)
  end
  
  it "should define an accessor method for the parent node when added" do
    n1 = Node.new(:name => 'n1')
    n2 = Node.new :parent => n1
    n2.n1.should eql(n1)
    n1.should_not respond_to(:n1)
  end
  
  it "should have defined an accessor method for the added child to the parent" do
    n1 = Node.new(:name => 'n1')
    n2 = Node.new :name => 'n2', :child => n1
    n1.n2.should eql(n2)
  end

  it "should have defined an accessor method for the added parent to the child" do
    n1 = Node.new(:name => 'n1')
    n2 = Node.new :name => 'n2', :parent => n1
    n1.n2.should eql(n2)
  end

end