public void Update()
{
Point newPosition = Snake.CalculateNewPosition(Width, Height);
Entity collisionEntity = EntityOccupyingPosition(newPosition);
ClearedPositions.Clear();
if (collisionEntity == null)
{
ClearedPositions.Add(Snake.Elements[Snake.Elements.Count - 1].Position);
Snake.Move(newPosition);
}
else if (!newPosition.Equals(Snake.GetPosition()))
{
if (collisionEntity is Fruit)
{
Snake.EatFruit(collisionEntity.GetPosition());
Entities.Remove(collisionEntity);
GenerateFruit();
}
else if (collisionEntity is Mouse)
{
Snake.EatMouse(collisionEntity.GetPosition());
Entities.Remove(collisionEntity);
}
else if (collisionEntity is Obstacle)
{
ClearedPositions.Add(Snake.Elements[Snake.Elements.Count - 1].Position);
Snake.EatObstacle(collisionEntity.GetPosition());
if (Snake.Lives <= 0)
{
GameOver = true;
return;
}
}
else if (collisionEntity is Snake)
{
ClearedPositions.Add(Snake.Elements[Snake.Elements.Count - 1].Position);
List <Point> removedPositions = Snake.EatSelf(newPosition);
if (removedPositions != null)
{
foreach (Point position in removedPositions)
{
ClearedPositions.Add(position);
}
}
}
else if (collisionEntity is Powerup)
{
Powerup powerup = (Powerup)collisionEntity;
ClearedPositions.Add(Snake.Elements[Snake.Elements.Count - 1].Position);
if (powerup.Effect.Variant == Effect.EffectVariant.Shrink)
{
List <Element> removedElements = Snake.Elements.GetRange(Snake.Size() / 2, Snake.Size() / 2 + Snake.Size() % 2);
foreach (Element element in removedElements)
{
ClearedPositions.Add(element.Position);
}
}
Snake.EatPowerup(collisionEntity.GetPosition(), ((Powerup)collisionEntity).Effect);
Entities.Remove(collisionEntity);
}
}
List <Entity> removedEntities = new List <Entity>();
bool powerupExists = false, mouseExists = false;
for (int i = 0; i < Entities.Count; i++)
{
if (Entities[i] is Powerup)
{
Powerup powerup = (Powerup)Entities[i];
if (powerup.SpawnDuration > 0)
{
powerup.LowerDuration();
powerupExists = true;
}
else
{
ClearedPositions.Add(powerup.GetPosition());
removedEntities.Add(powerup);
powerupExists = false;
}
}
if (Entities[i] is Mouse)
{
Mouse mouse = (Mouse)Entities[i];
Point newMousePosition = mouse.CalculateNewPosition();
ClearedPositions.Add(mouse.GetPosition());
if (newMousePosition.X >= Height || newMousePosition.Y >= Width || newMousePosition.X < 0 || newMousePosition.Y < 0)
{
removedEntities.Add(mouse);
}
else
{
mouse.Move(newMousePosition);
mouseExists = true;
}
}
}
foreach (Entity entity in removedEntities)
{
Entities.Remove(entity);
}
if (!powerupExists && !Snake.IsEffectActive() && IsDrawn(1))
{
GeneratePowerup();
}
if (Snake.IsEffectActive() && Snake.Effect.Duration > 0)
{
Snake.Effect.LowerDuration();
}
else
{
Snake.EndEffect();
}
if (!mouseExists && IsDrawn(1))
{
GenerateMouse();
}
if (Snake.Score >= nextStage)
{
GenerateObstacle();
nextStage += Stage;
}
}