package eu.alfred.recommendation_engine;

import java.util.HashMap;

import java.util.HashSet;

import java.util.List;

import java.util.Map;

import java.util.Set;

import eu.alfred.event_manager.model.*;

import org.junit.Before;

import org.junit.Test;

import static org.junit.Assert.assertEquals;

public class EventWeightsCalculatorTests {

  private EventWeightsCalculator eWCalc = new EventWeightsCalculator();

  private Map<Event,Integer> initialEvents;

  private Set<Event> eventsToBeAdded = new HashSet<Event>();

  Event eventA = new Event(); 

  Event eventB = new Event(); 

  Event eventC = new Event();

  Event eventD = new Event();

  Event eventE = new Event();

  @Before

  public void setup() {

      initialEvents = new HashMap<Event,Integer>();

      eventA.setEventID("eventA");

      eventB.setEventID("eventB");

      eventC.setEventID("eventC");

      eventD.setEventID("eventD");

      eventE.setEventID("eventE");

      eventsToBeAdded.add(eventA);

      eventsToBeAdded.add(eventB);

      eventsToBeAdded.add(eventC);

  }

  @Test

  public void testAssignWeightsToEventsWithEmptyInitialEvents() {

      int weightToBeAssigned = 2;

      eWCalc.assignWeightsToEvents(initialEvents, eventsToBeAdded, weightToBeAssigned);

      assertEquals(new Integer(weightToBeAssigned),initialEvents.get(eventA));

      assertEquals(new Integer(weightToBeAssigned),initialEvents.get(eventB));

      assertEquals(new Integer(weightToBeAssigned),initialEvents.get(eventC));

  }

  @Test

  public void testAssignWeightsToEventsWithPresentInitialEvents() {

      // assign initial weight to some events

      int weightForPreExistingEvents = 3;

      eWCalc.assignWeightsToEvents(initialEvents, eventsToBeAdded, weightForPreExistingEvents);

      assertEquals(new Integer(weightForPreExistingEvents),initialEvents.get(eventA));

      assertEquals(new Integer(weightForPreExistingEvents),initialEvents.get(eventB));

      assertEquals(new Integer(weightForPreExistingEvents),initialEvents.get(eventC));

      eventsToBeAdded.add(eventD);

      eventsToBeAdded.add(eventE);

      int weightToBeAssigned = 2;

      eWCalc.assignWeightsToEvents(initialEvents, eventsToBeAdded, weightToBeAssigned);

      assertEquals(new Integer(weightToBeAssigned+weightForPreExistingEvents),initialEvents.get(eventA));

      assertEquals(new Integer(weightToBeAssigned+weightForPreExistingEvents),initialEvents.get(eventB));

      assertEquals(new Integer(weightToBeAssigned+weightForPreExistingEvents),initialEvents.get(eventC));

      assertEquals(new Integer(weightToBeAssigned),initialEvents.get(eventD));

      assertEquals(new Integer(weightToBeAssigned),initialEvents.get(eventE));

  }

  @Test

  public void testRankingBasedOnWeights() {

      int weightToBeAssigned = 2;

      eWCalc.assignWeightsToEvents(initialEvents, eventsToBeAdded, weightToBeAssigned);

      Set<Event> additionalEvents = new HashSet<Event>();

      additionalEvents.add(eventC);

      int extraWeight = 5;

      eWCalc.assignWeightsToEvents(initialEvents, additionalEvents, extraWeight);

      List<Event> sortedEvents = eWCalc.sortByWeight(initialEvents);

      assertEquals(sortedEvents.get(0),eventC);

  }

}