import Foundation
import SwiftUI
import UIKit
import simd

@available(iOS 18.0, *)
struct MeshGradientView: View {
  @State private var isAnimating = false
  @ObservedObject var options: Options
  @State var dimension: Int = 0
  
  var body: some View {
    if options.error != nil {
      ErrorMessage(message: options.error)
    } else {
			VStack {
				MeshGradient(
					width: dimension,
					height: dimension,
					points: options.points,
					colors: isAnimating ? options.animatedColors : options.colors,
					smoothsColors: true
				).onAppear{
					if (options.points.count > 0) {
						dimension = Int(sqrt(Double(options.points.count)))
					}
					
					if (options.animatedColors.count > 0 && options.frequency != nil) {
						withAnimation(
							.easeInOut( duration: options.frequency!)
							.repeatForever(autoreverses: true)
						) {
							isAnimating.toggle()
						}
					}
				}.ignoresSafeArea(.all)
			}
		}
  }
}

@available(iOS 18.0, *)
class MeshGradientUIView: UIView {
  private var hostingController: UIHostingController<MeshGradientView>?
  private var options = Options()
  
  @objc func setFrequency (_ frequency: NSNumber) {
    options.frequency = Double(truncating: frequency)
  }
  
  @objc func setAnimatedColors (_ hexArray: NSArray) {
    do {
      let colors = try getColors(hexArray: hexArray)
      options.animatedColors = colors
    } catch {
      options.error = "Please check animated color attribute"
    }
  }
  
  @objc func setColors (_ hexArray: NSArray) {
    do {
      let colors = try getColors(hexArray: hexArray)
      options.colors = colors
    } catch {
      options.error = "Please check color attribute"
    }
  }
  
  @objc func setPoints(_ val: NSArray) {
    var simdArray: [SIMD2<Float>] = []

    for element in val {
      if let tuple = element as? NSArray,
        let x = tuple[0] as? NSNumber,
        let y = tuple[1] as? NSNumber {
        let simdPoint = SIMD2<Float>(x.floatValue, y.floatValue)
        simdArray.append(simdPoint)
      } else {
        options.error = "Please check points attribute"
      }
    }
    options.points = simdArray
  }
  
  override init(frame: CGRect) {
    super.init(frame: frame)
    setupView()
  }
    
  required init?(coder aDecoder: NSCoder) {
    super.init(coder: aDecoder)
    setupView()
  }
  
  private func setupView() {
    let view = MeshGradientView(options: options)
    let hostingController = UIHostingController(rootView: view)
    
    self.hostingController = hostingController
    
    hostingController.view.translatesAutoresizingMaskIntoConstraints = false
    
    self.addSubview(hostingController.view)
    
    NSLayoutConstraint.activate([
      hostingController.view.topAnchor.constraint(equalTo: self.topAnchor),
      hostingController.view.bottomAnchor.constraint(equalTo: self.bottomAnchor),
      hostingController.view.leadingAnchor.constraint(equalTo: self.leadingAnchor),
      hostingController.view.trailingAnchor.constraint(equalTo: self.trailingAnchor)
    ])
  }
}

@available(iOS 18.0, *)
struct ErrorMessage: View {
	var message: String = ""
	
	init (message: String?) {
		if let message {
			self.message = message
		}
	}
	
	var body: some View {
		VStack {
			Text(self.message)
				.foregroundColor(.white)
				.padding(16)
		}
		.background(.red)
		.cornerRadius(16)
	}
}


@available(iOS 18.0, *)
@objc(RNMeshGradient)
class RNMeshGradient: RCTViewManager {
	@objc
	override func view() -> UIView! {
			return MeshGradientUIView()
	}
	
	@objc
	override static func requiresMainQueueSetup() -> Bool {
		return true
	}
}