import SpriteKit
import SwiftUI

class GameScene: SKScene, SKPhysicsContactDelegate {
    var thrustActive: Binding!
    var rotationDegrees: Binding!

    private var rocket: SKSpriteNode!
    private var base: SKSpriteNode!
    private var background: SKSpriteNode!

    override func sceneDidLoad() {
        super.sceneDidLoad()

        // Remove the default background color
        backgroundColor = .clear

        // Create a black SKShapeNode that fills the entire scene
        let blackBG = SKShapeNode(rect: CGRect(origin: .zero, size: size))
        blackBG.fillColor = .black
        blackBG.strokeColor = .clear
        blackBG.zPosition = -10 // behind everything else
        addChild(blackBG)

        // Center point for alignment
        let centerX = size.width / 2
        let centerY = size.height / 2

        // Add the base (below the rocket, centered horizontally)
        base = SKSpriteNode(imageNamed: "Base")
        base.size = CGSize(width: 60, height: 10)
        base.position = CGPoint(x: centerX, y: centerY - 25)
        base.zPosition = 1
        addChild(base)

        base.physicsBody = SKPhysicsBody(rectangleOf: base.size)
        base.physicsBody?.isDynamic = false
        base.physicsBody?.categoryBitMask = PhysicsCategory.base
        base.physicsBody?.contactTestBitMask = PhysicsCategory.rocket
        base.physicsBody?.collisionBitMask = PhysicsCategory.rocket

        // Add the rocket (centered)
        rocket = SKSpriteNode(imageNamed: "Rocket")
        rocket.size = CGSize(width: 15, height: 25) // Adjusted size
        rocket.position = CGPoint(x: size.width / 2, y: size.height / 2)
        rocket.zRotation = 0
        rocket.zPosition = 1
        addChild(rocket)

        // Rocket physics body
        rocket.physicsBody = SKPhysicsBody(rectangleOf: rocket.size)
        rocket.physicsBody?.isDynamic = true
        rocket.physicsBody?.linearDamping = 0.02
        rocket.physicsBody?.angularDamping = 0.02
        rocket.physicsBody?.allowsRotation = true
        rocket.physicsBody?.categoryBitMask = PhysicsCategory.rocket
        rocket.physicsBody?.contactTestBitMask = PhysicsCategory.base | PhysicsCategory.background
        rocket.physicsBody?.collisionBitMask = PhysicsCategory.base | PhysicsCategory.background

        // Physics World
        physicsWorld.gravity = CGVector(dx: 0, dy: -0.2)
        physicsWorld.contactDelegate = self
    }

    func configureBackground(imageName: String, position: CGPoint, scale: CGFloat = 1.0) {
        let bgTexture = SKTexture(imageNamed: imageName)

        background = SKSpriteNode(texture: bgTexture)
        background.size = CGSize(
            width: background.size.width * scale,
            height: background.size.height * scale
        )
        background.position = position
        background.zPosition = -1
        addChild(background)

        // Create a physics body from the texture, ignoring any pixels with alpha < 1.0
        background.physicsBody = SKPhysicsBody(
            texture: bgTexture,
            alphaThreshold: 1.0,
            size: background.size
        )
        background.physicsBody?.isDynamic = false
        background.physicsBody?.categoryBitMask = PhysicsCategory.background
        background.physicsBody?.contactTestBitMask = PhysicsCategory.rocket
        background.physicsBody?.collisionBitMask = PhysicsCategory.rocket
    }

    override func update(_ currentTime: TimeInterval) {
        // Apply rotation based on gesture
        if rotationDegrees.wrappedValue != 0 {
            rocket.zRotation = (rotationDegrees.wrappedValue + 90) * .pi / 180
        }

        // Apply thrust if active
        if thrustActive.wrappedValue {
            let thrustMagnitude: CGFloat = 4.0
            let radians = rocket.zRotation + .pi / 2
            let dx = cos(radians) * thrustMagnitude
            let dy = sin(radians) * thrustMagnitude
            rocket.physicsBody?.applyForce(CGVector(dx: dx, dy: dy))
        }
    }

    func didBegin(_ contact: SKPhysicsContact) {
        let contactMask = contact.bodyA.categoryBitMask | contact.bodyB.categoryBitMask

        if contactMask == PhysicsCategory.rocket | PhysicsCategory.base {
            print("Rocket has landed on the base!")
        }

        if contactMask == PhysicsCategory.rocket | PhysicsCategory.background {
            print("Rocket collided with the background!")
        }
    }
}

struct PhysicsCategory {
    static let rocket: UInt32 = 0x1 << 0
    static let base: UInt32 = 0x1 << 1
    static let background: UInt32 = 0x1 << 2
}