package rules;

import static org.junit.Assert.*;

import org.junit.Before;
import org.junit.Test;

public class RulesForNextGenerationTest {
  private RulesForNextGeneration inNextGeneration;

  @Before
  public void setup() {
    inNextGeneration = new RulesForNextGeneration();
  }

  @Test
  public void deadCellWith_0_LiveNeighbors_StaysDead() throws Exception {
    assertIsDeadNextTime(new Cell().withLiveNeighbors(0));
  }

  @Test
  public void deadCellWith_1_LiveNeighbors_StaysDead() throws Exception {
    assertIsDeadNextTime(new Cell().withLiveNeighbors(1));
  }

  @Test
  public void deadCellWith_2_LiveNeighbors_StaysDead() throws Exception {
    assertIsDeadNextTime(new Cell().withLiveNeighbors(2));
  }

  @Test
  public void deadCellWith_3_LiveNeighbors_ComesAlive() throws Exception {
    assertIsAliveNextTime(new Cell().withLiveNeighbors(3));
  }

  @Test
  public void deadCellWith_4_LiveNeighbors_staysdead() throws Exception {
    assertIsDeadNextTime(new Cell().withLiveNeighbors(4));
  }

  @Test
  public void liveCellWith_0_LiveNeighbors_Dies() throws Exception {
    assertIsDeadNextTime(new Cell().thatIsAlive().withLiveNeighbors(0));
  }

  @Test
  public void liveCellWith_1_LiveNeighbors_Dies() throws Exception {
    assertIsDeadNextTime(new Cell().thatIsAlive().withLiveNeighbors(1));
  }

  @Test
  public void liveCellWith_2_LiveNeighbors_StaysAlive() throws Exception {
    assertIsAliveNextTime(new Cell().thatIsAlive().withLiveNeighbors(2));
  }

  @Test
  public void liveCellWith_3_LiveNeighbors_StaysAlive() throws Exception {
    assertIsAliveNextTime(new Cell().thatIsAlive().withLiveNeighbors(3));
  }

  @Test
  public void liveCellWith_4_LiveNeighbors_Dies() throws Exception {
    assertIsDeadNextTime(new Cell().thatIsAlive().withLiveNeighbors(4));
  }

  private void assertIsAliveNextTime(Cell cell) {
    assertTrue(inNextGeneration.itTurnsOutThat(cell).comesAlive());
  }

  private void assertIsDeadNextTime(Cell cell) {
    assertFalse(inNextGeneration.itTurnsOutThat(cell).comesAlive());
  }

  // Test list

  // TODO a dead cell with 0 live neighbors stays dead.
  // TODO a dead cell with 1 live neighbors stays dead.
  // TODO a dead cell with 2 live neighbors stays dead.
  // TODO a dead cell with 3 live neighbors comes alive.
  // TODO a dead cell with 4 live neighbors stays dead.

  // TODO a live cell with 0 live neighbors dies.
  // TODO a live cell with 1 live neighbor dies.
  // TODO a live cell with 2 live neighbors stays alive.
  // TODO a live cell with 3 live neighbors stays alive.
  // TODO a live cell with 4 live neighbors dies.

}