package  {

public class LeaderFlocker extends Flocker{
//The constructor class for the LeaderFlocker fish, which is programmed to swim in a figure-eight formation and avoid the other fish.
//Passes in a reference to the flock manager class, and the current x and y coordinates, and well as the speed of the fish.
public function LeaderFlocker(aMan:Manager, aX:Number=0, aY:Number=0, aSpeed:Number=0 )
{
    super(aMan, aX, aY, aSpeed);
    aMan.addChild(this);
}

//Calculates the Vector force every frame for guiding the fish.
package  {

    public class LeaderFlocker extends Flocker{
        //The constructor class for the LeaderFlocker fish, which is programmed to swim in a figure-eight formation and avoid the other fish.
        //Passes in a reference to the flock manager class, and the current x and y coordinates, and well as the speed of the fish.
        public function LeaderFlocker(aMan:Manager, aX:Number=0, aY:Number=0, aSpeed:Number=0 )
        {
            super(aMan, aX, aY, aSpeed);
            aMan.addChild(this);
        }

        //Calculates the Vector force every frame for guiding the fish.
        override protected function calcSteeringForce( ):Vector2{
            //the initial blank Vector to be eventually returned.
            var steeringForce:Vector2 = new Vector2( );

            //When the user clicks the screen, the seekingfoodpoint boolean is set to true, which overrides main steering force to simply move
            //towards the point that was clicked.
            if(seekingfoodpoint){
                //the arrival() method calculates the direction towards the spot that was clicked, and has the fish slow down as
                //the fish gets closer to the spot that was clicked, until eventually the fish reaches the point, which sets
                //seekingfoodpoint to false.
                steeringForce = steeringForce.add(arrival().multiply(500));

            }
            //the fish is not seeking food, and will swim around normally.
            else{
                //adds the flowfield steering force, which makes the fish move in the figure-eight formation
                steeringForce=steeringForce.add(flowField().multiply((500)));

                //if the fish is in danger of moving off of the screen, then reverse the steering force
                //so that the fish does not move off-screen.
                if((this.x<150 && steeringForce.x<0) || (this.x>770 && steeringForce.x>0))
                    steeringForce=new Vector2(-steeringForce.x,steeringForce.y);
                if((this.y<200 && steeringForce.y<0) || (this.y>620 && steeringForce.y>0))
                    steeringForce=new Vector2(steeringForce.x,-steeringForce.y);
            }

            //if the force associated with the separation of fishes is present (which it normally is not unless other fish are
            //very close) then add this force to the steeringForce.
            var v:Vector2=separation();
            if((v.x!=0 && v.y!=0) ){
                steeringForce = steeringForce.add(separation().multiply(500));
            }
            return steeringForce;
        }

        //This function is responsible for the figure-eight direction that the koi generally moves in.
        public function flowField():Vector2{
            var futurePosition:Vector2;
            var flowdir:Vector2;
            //the flowField method is divided into 3 sections, based on where the fish is horizontally.

            //if the fish has an s value of less than 400, then a spot slightly ahead of the fish is found. We then calculate
            //where that point is relative to a point near the middle of the screen and off to the left a little.
            //this vector is rotated 90 degrees to get a vector that turns the fish slowly around the
            //point near the middle of the screen in a counterclockwise direction.
            if(this.x< 400){
                futurePosition = position.add(fwd.multiply(speed*.1));
                flowdir= futurePosition.subtract(new Vector2(600,400));
                flowdir=flowdir.perpRight();
                flowdir.normalize();
                return flowdir;
            }

            //if the fish is near the middle of the screen, the vector returned will be in a diagonal direction depending upon
            //the fish's horizontal velocity. If the fish is moving to the right, the fish will keep moving right and downward.
            //If it is going left, the fish will move left and downward.
            else if(this.x>=400 && this.x<600){
                if(fwd.x>0)
                    return new Vector2(.333,.9);
                else
                    return new Vector2(-.333,.9);
            }
            //if the fish is far to the right, there is a similar idea from when the fish is far to the left, except since
            //the fish is on the opposite end, the fish will be turning in the opposite direction.
            else{
                futurePosition = position.add(fwd.multiply(speed*.1));
                flowdir= futurePosition.subtract(new Vector2(400,400));
                flowdir=flowdir.perpRight().perpRight().perpRight();
                flowdir.normalize();
                return flowdir;
            }
        }
    }
}