#!/usr/bin/env ruby
# -*- coding: utf-8 -*-

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

describe 'Recommendation::Engine' do
  describe 'recommendation' do
    it 'should be suggesting interesting products' do
      expected = {"The Night Listener"=>3.3477895267131017, "Lady in the Water"=>2.8325499182641614, "Just My Luck"=>2.530980703765565}


      supervisor = Recommendation::Supervisor.new(visitors)
      supervisor.train(new_comer)
      engine = Recommendation::Engine.new

      new_comer.keys[0].should be_eql 'Toby'
      engine.recommendation(supervisor.table, new_comer.keys[0]).should be_eql expected
    end
  end

  describe 'top_matches' do
    it 'should be finding similar users' do
      expected ={"Lisa Rose"=>0.9912407071619299, "Mick LaSalle"=>0.9244734516419049, "Claudia Puig"=>0.8934051474415647, "Jack Matthews"=>0.66284898035987, "Gene Seymour"=>0.38124642583151164}

      supervisor = Recommendation::Supervisor.new(visitors)
      supervisor.train(new_comer)
      engine = Recommendation::Engine.new

      new_comer.keys[0].should be_eql 'Toby'
      engine.top_matches(supervisor.table, new_comer.keys[0]).should be_eql expected
    end
  end

  describe 'transform_table ' do
    it 'should return reversed critics' do
      supervisor = Recommendation::Supervisor.new(visitors)
      supervisor.train(new_comer)
      engine = Recommendation::Engine.new

      movies = supervisor.transform_table
      movies.should be_eql reversed_critics
    end
  end

  describe 'reversed critics' do
    it 'should be found similar items' do
      expected = {"You, Me and Dupree"=>0.6579516949597695, "Lady in the Water"=>0.4879500364742689, "Snake on the Plane"=>0.11180339887498941, "The Night Listener"=>-0.1798471947990544, "Just My Luck"=>-0.42289003161103106}

      supervisor = Recommendation::Supervisor.new(visitors)
      supervisor.train(new_comer)
      engine = Recommendation::Engine.new

      movies = supervisor.transform_table

      new_comer.values[0].keys[2].should be_eql 'Superman Returns'
      engine.top_matches(movies, new_comer.values[0].keys[2]).should be_eql expected
    end
  end

  describe 'recommendation for the unexisting user' do
    it 'should return empty array' do
      expected = {}

      supervisor = Recommendation::Supervisor.new(visitors)
      supervisor.train(new_comer)
      engine = Recommendation::Engine.new

      engine.recommendation(supervisor.table, 'hoge').should be_eql expected
    end
  end

  describe 'top_matches for the unexisting item' do
    it 'should return all zero score' do
      expected = {"Toby"=>0, "Mick LaSalle"=>0, "Michael Phillips"=>0, "Lisa Rose"=>0, "Jack Matthews"=>0}

      supervisor = Recommendation::Supervisor.new(visitors)
      supervisor.train(new_comer)
      engine = Recommendation::Engine.new

      engine.top_matches(supervisor.table, 'fuga').should be_eql expected
    end
  end
end

def new_comer
  {
    'Toby' => {
      'Snake on the Plane' => 4.5,
      'You, Me and Dupree' => 1.0,
      'Superman Returns'   => 4.0
    }
  }
end

def visitors
  {
    'Lisa Rose' => {
      'Lady in the Water'  => 2.5,
      'Snake on the Plane' => 3.5,
      'Just My Luck'       => 3.0,
      'Superman Returns'   => 3.5,
      'You, Me and Dupree' => 2.5,
      'The Night Listener' => 3.0
    },

    'Gene Seymour' => {
      'Lady in the Water'  => 3.0,
      'Snake on the Plane' => 3.5,
      'Just My Luck'       => 1.5,
      'Superman Returns'   => 5.0,
      'The Night Listener' => 3.0,
      'You, Me and Dupree' => 3.5
    },

    'Michael Phillips' => {
      'Lady in the Water'  => 2.5,
      'Snake on the Plane' => 3.0,
      'Superman Returns'   => 3.5,
      'The Night Listener' => 4.0
    },

    'Claudia Puig' => {
      'Snake on the Plane' => 3.5,
      'Just My Luck'       => 3.0,
      'The Night Listener' => 4.5,
      'Superman Returns'   => 4.0,
      'You, Me and Dupree' => 2.5
    },

    'Mick LaSalle' => {
      'Lady in the Water'  => 3.0,
      'Snake on the Plane' => 4.0,
      'Just My Luck'       => 2.0,
      'Superman Returns'   => 3.0,
      'The Night Listener' => 3.0,
      'You, Me and Dupree' => 2.0
    },

    'Jack Matthews' => {
      'Lady in the Water'  => 3.0,
      'Snake on the Plane' => 4.0,
      'The Night Listener' => 3.0,
      'Superman Returns'   => 5.0,
      'You, Me and Dupree' => 3.5
    }
  }
end

def reversed_critics
  {
    "Lady in the Water" => {
      "Lisa Rose"        => 2.5,
      "Gene Seymour"     => 3.0,
      "Michael Phillips" => 2.5,
      "Mick LaSalle"     => 3.0,
      "Jack Matthews"    => 3.0
    },

    "Snake on the Plane" => {
      "Lisa Rose"        => 3.5,
      "Gene Seymour"     => 3.5,
      "Michael Phillips" => 3.0,
      "Claudia Puig"     => 3.5,
      "Mick LaSalle"     => 4.0,
      "Jack Matthews"    => 4.0,
      "Toby"             => 4.5
    },

    "Just My Luck" => {
      "Lisa Rose"        => 3.0,
      "Gene Seymour"     => 1.5,
      "Claudia Puig"     => 3.0,
      "Mick LaSalle"     => 2.0
    },

    "Superman Returns" => {
      "Lisa Rose"        => 3.5,
      "Gene Seymour"     => 5.0,
      "Michael Phillips" => 3.5,
      "Claudia Puig"     => 4.0,
      "Mick LaSalle"     => 3.0,
      "Jack Matthews"    => 5.0,
      "Toby"             => 4.0
    },

    "You, Me and Dupree" => {
      "Lisa Rose"        => 2.5,
      "Gene Seymour"     => 3.5,
      "Claudia Puig"     => 2.5,
      "Mick LaSalle"     => 2.0,
      "Jack Matthews"    => 3.5,
      "Toby"             => 1.0
    },

    "The Night Listener" => {
      "Lisa Rose"        => 3.0,
      "Gene Seymour"     => 3.0,
      "Michael Phillips" => 4.0,
      "Claudia Puig"     => 4.5,
      "Mick LaSalle"     => 3.0,
      "Jack Matthews"    => 3.0
    }
  }
end