//----------------------------\
//Main Variables              |
//----------------------------/
var bulletID:Number = 0;
var maxSpeed:Number = 5;
var speed:Number = 0;
var accel:Number = 0.15;
var decel:Number = 0.95;
var backSpeed:Number = 0;
var maxBackSpeed:Number = -5;
var healthPoints:Number = 100;
var cheatsOn:Boolean = false;
var isMouseDown:Boolean = false;
var numBullets:Number = 0;
var ammo:Number = 10;
var reloadTime:Number = 0;
var numBullets:Number = 0;
var numEnemies:Number = 0;
var bulletList:Array = new Array ();
var enemyList:Array = new Array ();
var bulletSpeed:Number = 10;
var canFire:Boolean = true;
var radians:Number = Math.PI/180;
var enemySpeed:Number = 2;
var turnRate:Number = 0.1;
var canSpawn:Boolean = true;
var spDelay:Number = 0;
var score:Number = 0;

//zombies 
var moveX:Number = 0;
var moveY:Number = 0;

// Timers
var fireTime:Number = 0;
var reloadTime:Number = 0;


//boundry variables
var tankW = Tank._width /2;
var tankH = Tank._height /2;
var stageW = Stage.width;
var stageH = Stage.height;
var boundT = 0 + tankH;
var boundR = stageW - tankW
var boundL = 0 + tankW;
var boundB = stageH - 100 - tankH;

//sound variables
fire = new Sound ();
fire.attachSound("Fire")

//---------------------------------------------------------

//---------------------------------\
// Find out if the mouse is down   |
//---------------------------------/

this.onMouseDown = function() //if Mouse mosue is down, set isMouseDown to true
{
	isMouseDown = true;
	trace("Down")
}
this.onMouseUp = function() //if Mouse mosue is up, set isMouseDown to false
	{
	isMouseDown = false;
	trace("Up")
}
//---------------------------------------------------------

//----------------\
// Define Angle   |
//----------------/

Mouse.hide();

Tank.onEnterFrame = function()
{
	if(canSpawn == true){ // if canSpawn is equal to true, run the code.
		spawnEnemy() //Run function "spawnEnemy"
		canSpawn = false // set canSpawn to false so the spawn delay can be triggered
	 }
	 for (i = 0; i <= numEnemies; i++){
		  if (Tank.hitTest(enemyList[i]) && speed <= -2){ //if player drives over zombies past a set speed, then kill the zombies.
			enemyList[i].removeMovieClip();
       		enemyList.splice(i,1);
       		numEnemies--;
			score+=5  // increase score by 5
			 }
		 if (Tank.hitTest(enemyList[i]) && speed >= 2){//if player reverses over zombies past a set speed, then kill the zombies.
			enemyList[i].removeMovieClip();
       		enemyList.splice(i,1);
       		numEnemies--;
			score+=5 // increase score by 5
		 }
			
	 }
	 if(healthPoints <= 0){
		 gotoAndStop(2)
	 }
	mouseCursor.gotoAndPlay(reloadTime)
	ammoLeft = "Current ammo: " + ammo / 2 // make the text tell us the current ammo
	sped = "Speed: " + Math.round(speed) // make the text tell us the current speed
	turRot = "Turret Rotation: "+ Math.round(Tank.turret._rotation); // make the text tell us the current turret rotation
	tankRot = "Tank Rotation: " + Math.round(Tank._rotation); // make the text tell us the current tank rotation
	hP = "Health Points: " + Math.round(healthPoints) // make the text tell us the current HP
	scoreTxt = "Score : " + score // make the text tell us the current score
	//----------------------------------------------------------
	
	//----------------\
	// Define Angle   |
	//----------------/
	
	var __x = _xmouse - Tank._x; 
	var __y = _ymouse - Tank._y;
	var angle = Math.atan2(__y, __x) * 180 / Math.PI; //make a variable to difine angle so it can be used to rotate the turret
	//----------------------------------------------------------

	mouseCursor._x = _xmouse; //make the crosshair follow the mouse
	mouseCursor._y = _ymouse;
	
	
	if(Tank._x > boundR){ //if tank xPos is more than the right boundry, tank xPos = boundL
		Tank._x = boundR;
		trace("At Right Boundry")
	}
	if(Tank._x < boundL){//if tank xPos is less than the left boundry, tank xPos = boundL
		Tank._x = boundL;
		trace("At Left Boundry")
	}
	if(Tank._y < boundT){ //if tank xPos is less than the left boundry, tank xPos = boundL
		Tank._y = boundT;
		trace ("At Top  Boundry")
	}
	if(Tank._y > boundB){
		Tank._y = boundB;
		trace("At Bottom Boundry")
}
	
	
	
	//-------------------------\
	//Character movement code  |
	//-------------------------/
        if (Key.isDown(Key.UP))// if the up key has been pressed increase speed by acceleration until it is equal to maxSpeed
	{
		trace("Up key is pressed");
		if (speed <= maxSpeed){
			speed += accel;
		}
	}else //else times the speed by decel
	{
		speed *= decel;
	}
	if(Key.isDown(Key.DOWN)){ //if the down key has been pressed decrease speed by acceleration
		if(Math.abs(speed) <= maxSpeed){ // Math.abs so the speed can go into negative
			speed -= accel;
		}
	}
	else{ //else times the speed by decel
		speed *= decel;
	}
    if (Key.isDown(Key.RIGHT))// if the right key is pressed,rotate the tank right.
	{
		trace("Right Rotation");
		this._rotation += 2;
	}
	if (Key.isDown(Key.LEFT))// if the left key is pressed,rotate the tank left.
	{
	
		trace("Left Rotation");
		this._rotation -= 2;
	}
	
	//----------------------------------------------------------    
	//---------------\
	// Trigonometry  |
	//---------------/
	this._y += Math.sin(Tank._rotation / 180 * Math.PI) * speed;// allows the tank to move forward in the direction it is facing
	this._x += Math.cos(Tank._rotation / 180 * Math.PI) * speed;
	//----------------------------------------------------------

	//------------------\
	//Turret Rotation   |
	//------------------/
	Tank.turret._rotation = angle - Tank._rotation; // makes the turret follow the mouse.
	
	//----------------------------------------------------------
	//--------------------\
	// Bullets & reloading|
	//--------------------/
	if (ammo <= 0){ // if ammo is less than or equal to 0, run the "reload" function with the number 100
		 reload(100); // givees it a reload time so you can't spam shoot.
	}
	if(isMouseDown == true){ //if mouse is down,ammo >= 1 and canFire = true, run the "shoot" function,decrease the ammo by 1 and set canFire to false.
		if (ammo >= 1){// this will place a delay between each fire to make it feel more realisitc
			if (canFire == true){
				shoot()
				ammo -=1
				canFire = false
		}
	}
}
	//------------------------------------------------------------------
 	//----------------\
	// Function calls |
	//----------------/
	rotateBullets()
	fireDelay(40)
	spawnDelay(60)
	moveEnemy()
	deathBox()
	//------------------------------------------------------------------
		


};  // onEnterFrame end

function deathBox(){ // function to kill bullets when it collides with the black boxes around the map.
	for(i = 1; i <= numBullets; i++){
		if(bulletList[i].hitTest(box1)){
		bulletList[i].removeMovieClip();
		}
	if(bulletList[i].hitTest(box2)){
	  
	 bulletList[i].removeMovieClip();
	   }
	if(bulletList[i].hitTest(box3)){
	  bulletList[i].removeMovieClip();
	   }
	   if(bulletList[i].hitTest(box4)){
	 bulletList[i].removeMovieClip();
	 }
	}
}
function spawnEnemy() {
	numEnemies++; //increase the numEnemies variable by 1 everytime an enemy is spawned.
	trace("Number of Enemies: " + numEnemies); //tells us how many enemys there are.
	enemyList[numEnemies] = this.attachMovie("Enemy", "EnemyName" + numEnemies, this.getNextHighestDepth(), { _x:-50 , _y:100}); // spawn enemies at the x cord of -50 so its slightly off the screen. 
}
function moveEnemy(){
	if (numEnemies > 0){ //if there are moire than one enemy on the screen.
	for(num = 1; num <= numEnemies; num++) {
	doFollow(enemyList[num],Tank,1) //make the enemys walk towards to tank
	if(Tank.hitTest(enemyList[num])){ //if the enemys hit the tank,decrease health by 0.03 every frame
	   healthPoints-=0.03
	   }
		for(i = 1; i <= numBullets; i++) {
	    if(enemyList[num].hitTest(bulletList[i])){ //if bullet hits an enemy remove the bullet
		enemyList[num].removeMovieClip();
        enemyList.splice(num,1);
        numEnemies--;
		bulletList[i].removeMovieClip();
		score+=10//increase score when an enemy is killed
		}
		}
	}
}
}
function shoot() {
	numBullets++;//increase the numBullets variable by 1 everytime a bullet is spawned.
	bulletList[numBullets] = this.attachMovie("Bullet", "bulletName" + numBullets, this.getNextHighestDepth(), { _x:Tank._x , _y:Tank._y}); 
	ammo--; //decrease ammo by one
	bulletList[numBullets]._rotation = Tank.turret._rotation + Tank._rotation //make the bullet face the direction the turret it rotated to
	fire.start();//play the souund "fire" when you shoot.
}

function rotateBullets(){
	for(num = 1; num <= numBullets; num++) {
		bulletList[num]._y += Math.sin(bulletList[num]._rotation / 180 * Math.PI) * bulletSpeed; //makes the bullets travel towards the direction it is facing.
 		bulletList[num]._x += Math.cos(bulletList[num]._rotation / 180 * Math.PI) * bulletSpeed;
	}
}
function reload (time:Number){ //1 second = 24,5 seconds = 120.
	if (reloadTime < time){//if reload is less than time, increase roloadTime every frame and set canFire to false
		reloadTime ++
		canFire = false
	}
	if (reloadTime >= time){//if reload is more than or eqial to time, set ammo to 10,set relaodTime to 0 and canFire to true.
		ammo = 10
		reloadTime = 0
		canFire = true
	}
}
function doFollow(follower:MovieClip, target:MovieClip, enemySpeed:Number)
{
	var originalSpeed:Number = enemySpeed


	var distanceX:Number = target._x - follower._x;//calculate distance between follower and target
	var distanceY:Number = target._y - follower._y;

	
	distanceTotal = Math.sqrt(distanceX * distanceX + distanceY * distanceY);//get total distance as one number
	
	if (target.hitTest(follower)){
		enemySpeed = 0;
	}else{
		enemySpeed = originalSpeed;
	}


		
		var moveDistanceX:Number = turnRate * distanceX / distanceTotal;//calculate how much to move
		var moveDistanceY:Number = turnRate * distanceY / distanceTotal;

		
		moveX += moveDistanceX;//increase current speed
		moveY += moveDistanceY;

		
		var totalmove = Math.sqrt(moveX * moveX + moveY * moveY);//get total move distance

		
		moveX = enemySpeed * moveX / totalmove;//apply easing
		moveY = enemySpeed * moveY / totalmove;

		
		follower._x += moveX;//move follower
		follower._y += moveY;

		
		follower._rotation = 180 * Math.atan2(moveY, moveX) / Math.PI;//rotate follower toward target


}

function fireDelay(i:Number){
	if (canFire == false){//the function for the fireDelay with chnagable delay times.
 	if (fireTime < i){
	 fireTime ++
 }
 	if (fireTime >= i){//if fireTime is more than or equal to i then fireTime will be reset and canFire will be set to true
 		fireTime = 0
 		canFire = true
	}
}
}
function spawnDelay (i:Number){//a fumction to prevent a flood of zombies spawning at once, Changable times to increase or descrease the delay.
	if (canSpawn == false){
		if (spDelay < i){
			spDelay++
	}
}
		if (spDelay>= i){//if spDelay is more than or equal to i then spDelay will be reset and ccanSpawn will be set to true
			spDelay = 0
			canSpawn = true
		}
}