#import "gamemodel.h"
#import "sprite.h"

@implementation GameModel

-(id) init
{
  [super init];

  sprites = [[NSMutableArray alloc] init];
  toAdd = [[NSMutableArray alloc] init];
  toRemove = [[NSMutableArray alloc] init];
  lastUpdate = 0.0;

  return self;
}

-(NSArray*) getSprites
{
  NSMutableArray* result = [[[NSMutableArray alloc] init] autorelease];

  [result addObjectsFromArray:sprites];
  [result removeObjectsInArray:toRemove];

  return result;
}

-(void) addSprite:(Sprite*)s
{
  if (![sprites containsObject:s] && ![toAdd containsObject:s])
    {
      [toAdd addObject:s];
    }
}

-(void) removeSprite:(Sprite*)s
{
  if (![toRemove containsObject:s] && [sprites containsObject:s])
    {
      [toRemove addObject:s];
    }
}

-(double) getWidth
{
  return 1.0;
}

-(double) getHeight
{
  return 1.0;
}

-(void) processRemovedSprites
{
  [sprites removeObjectsInArray:toRemove];
  [toRemove removeObjectsInRange:NSMakeRange(0, [toRemove count])];
}

-(void) processAddedSprites
{
  [sprites addObjectsFromArray:toAdd];
  [toAdd removeObjectsInRange:NSMakeRange(0, [toAdd count])];
}

-(void) update
{
  // get current time since 1970

  NSDate* currentDate = [NSDate date];
  NSTimeInterval currentTime = [currentDate timeIntervalSince1970];

  if (lastUpdate != 0.0)
    {
      for (int i = 0; i < [sprites count]; i++)
	{
	  [(Sprite*)[sprites objectAtIndex:i] updateForTime:currentTime - lastUpdate model:self];
	}
    }

	[self checkCollisions];
	
  [self processRemovedSprites];
  [self processAddedSprites];

  lastUpdate = currentTime;
}

-(void) checkCollisions
{
  for (int i = 0; i < [sprites count]; i++)
    {
      Sprite* s1 = [sprites objectAtIndex:i];

      for (int j = i + 1; j < [sprites count]; j++)
	{
	  Sprite* s2 = [sprites objectAtIndex:j];

	  if ([s1 collidesWith:s2])
	    {
	      [self handleCollisionSprite:s1 with:s2];
	    }
	}
    }
}

-(void) handleCollisionSprite:(Sprite*)s1 with:(Sprite*)s2
{
}

-(void) dealloc
{
  [sprites release];
  [toAdd release];
  [toRemove release];

  [super dealloc];
}

@end