Too many Enemies Spawning, and not colliding with Player - swift

Question

So I added this recent code (to keep enemy nodes in the borders of the screen) with help from #Fluidity from my last question, now my issue is that with this code, TOO many enemies are coming down, and they're not colliding with either the bullets the Player shoots, or the Player nodes themselves, like it was previously. Here's some code:
func createEnemy() {
let wait:SKAction = SKAction.wait(forDuration: 1.25)
//1.0 = 1.35
let block:SKAction = SKAction.run(launchEnemy)
let seq:SKAction = SKAction.sequence( [ wait, block ])
let repeated:SKAction = SKAction.repeatForever(seq)
self.run(repeated, withKey:"enemyLaunchAction")
self.run(seq, withKey:"EnemySpawnAction")
}
func launchEnemy() {
let EnemyMissile:EnemyClass = EnemyClass()
EnemyMissile.createEnemy("Enemy")
addChild(EnemyMissile)
let enemy = EnemyMissile.EnemyNode
// let randomX = arc4random_uniform( UInt32(screenWidth))
var randomX = CGFloat(arc4random_uniform(UInt32(self.size.width))) // This is not a perfect rando algo.
// Because our random x was from 0 through screenwidth, but .position works
// on -halfWidth through +halfWidth
randomX -= (self.frame.size.width / 2)
// Because spawning on the border will mean that the enemy is HALF out of view:
/*
right border: |
enemy # frame.maxX: x
- offset: x|
- size.w/2 x |
*/
enemy.position = CGPoint( x: CGFloat(randomX) - (screenWidth / 2), y: screenHeight + 50)
let action = SKAction.move(by: CGVector(dx: 0, dy: -400 + speedScore), duration: 5.0)
enemy.run(SKAction.repeatForever(action))
increaseSpeed()
print("enemy spawned!")
self.run(action, withKey:"LaunchEnemyAction")
let offset = CGFloat(5) // pixels, so enemy will have some spacing between borders.
if randomX > self.frame.maxX - offset - (enemy.size.width / 2) {
randomX = self.frame.maxX - offset - (enemy.size.width / 2)
}
else if randomX < self.frame.minX + offset + (enemy.size.width / 2) {
randomX = self.frame.minX + offset + (enemy.size.width / 2)
}
enemy.position.x = randomX
}
func keepEnemyInBounds() {
// A better way to do this would be to have a dictionary of enemies:
for node in self.children {
guard node.name == "enemy" else { continue }
let enemy = node as! SKSpriteNode
if enemy.position.x > frame.maxX - (enemy.size.width / 2) {
enemy.position.x = frame.maxX - (enemy.size.width / 2)
}
else if enemy.position.x < frame.minX + (enemy.size.width / 2) {
enemy.position.x = frame.minX + (enemy.size.width / 2)
}
}
}
override func update(_ currentTime: TimeInterval) {
launchEnemy()
}
override func didFinishUpdate() {
keepEnemyInBounds()
}
CONTACT LISTENER CODE:
func didBegin(_ contact: SKPhysicsContact) {
_ = contact.bodyA.categoryBitMask | contact.bodyB.categoryBitMask
if (contact.bodyA.categoryBitMask == BodyType.enemy.rawValue && contact.bodyB.categoryBitMask == BodyType.bullet.rawValue) {
if let missile = contact.bodyA.node! as? EnemyClass {
enemyMissileAndBullet(missile)
}
contact.bodyB.node?.name = "removeNode"
} else if ( contact.bodyA.categoryBitMask == BodyType.bullet.rawValue && contact.bodyB.categoryBitMask == BodyType.enemy.rawValue) {
if let missile = contact.bodyB.node! as? EnemyClass {
enemyMissileAndBullet(missile)
}
contact.bodyA.node?.name = "removeNode"
}
if ( contact.bodyA.categoryBitMask == BodyType.player.rawValue && contact.bodyB.categoryBitMask == BodyType.enemy.rawValue) {
createExplosion(contact.bodyB.node!.position , image:"explosion2")
contact.bodyB.node?.name = "removeNode"
updateScore(1)
subtractHealth()
playSound("shipExplosion")
} else if (contact.bodyA.categoryBitMask == BodyType.enemy.rawValue && contact.bodyB.categoryBitMask == BodyType.player.rawValue) {
createExplosion(contact.bodyA.node!.position , image:"explosion2")
contact.bodyA.node?.name = "removeNode"
updateScore(1)
subtractHealth()
playSound("shipExplosion")
}
}
EDIT:
Contact listener cleaned up: Requires player < missle < enemy
func didBegin(_ contact: SKPhysicsContact) {
let bodyA = contact.bodyA.categoryBitMask >= contact.bodyA.categoryBitMask ? contact.bodyA : contact.bodyB
let bodyB = contact.bodyA.categoryBitMask < contact.bodyA.categoryBitMask ? contact.bodyA : contact.bodyB
if contact.bodyA.categoryBitMask == BodyType.bullet.rawValue && contact.bodyB.categoryBitMask == BodyType.enemy.rawValue {
if let missile = contact.bodyA.node! as? EnemyClass {
enemyMissileAndBullet(missile)
}
contact.bodyB.node?.name = "removeNode"
}
else if contact.bodyA.categoryBitMask == BodyType.player.rawValue && contact.bodyB.categoryBitMask == BodyType.enemy.rawValue {
createExplosion(bodyB.node!.position , image:"explosion2")
bodyB.node?.name = "removeNode"
updateScore(1)
subtractHealth()
playSound("shipExplosion")
}
}