//
//  LNVoiceWaveView.swift
//  Lanu
//
//  Created by OneeChan on 2026/1/5.
//

import Foundation
import UIKit
import SnapKit


class LNVoiceWaveView: UIView {
    var itemCount = 5
    var duration = 0.17
    var fillColor: UIColor = .fill
    var itemWidth: CGFloat = 1.7
    private let stackView = UIStackView()
    private var itemViews: [UIView] = []
    
    override init(frame: CGRect) {
        super.init(frame: frame)
        
        setupViews()
    }
    
    func build() {
        stackView.arrangedSubviews.forEach {
            stackView.removeArrangedSubview($0)
            $0.removeFromSuperview()
        }
        itemViews.removeAll()
        
        let mid: Double = Double(itemCount - 1) / 2.0
        for index in 0..<itemCount {
            let scale = 0.3 + (mid - abs(Double(index) - mid)) * (0.7 / mid)
            let line = UIView()
            line.layer.cornerRadius = itemWidth * 0.5
            line.backgroundColor = fillColor
            stackView.addArrangedSubview(line)
            line.snp.makeConstraints { make in
                make.width.equalTo(itemWidth)
                make.height.equalToSuperview().multipliedBy(scale)
            }
            itemViews.append(line)
        }
    }
    
    func startAnimate() {
        for (index, view) in itemViews.enumerated() {
            let scaleAnim = CABasicAnimation(keyPath: "transform.scale.y")
            scaleAnim.fromValue = 0.7
            scaleAnim.toValue = 1.0
            scaleAnim.duration = duration
            scaleAnim.autoreverses = true
            scaleAnim.fillMode = .both
            
            let animationGroup = CAAnimationGroup()
            animationGroup.animations = [scaleAnim]
            animationGroup.duration = duration + Double(itemCount) * duration
            animationGroup.repeatCount = .infinity
            animationGroup.isRemovedOnCompletion = false
            animationGroup.fillMode = .both
            animationGroup.beginTime = CACurrentMediaTime() + Double(index) * 0.1
            
            view.layer.add(animationGroup, forKey: "scaleAnimated")
        }
    }
    
    func stopAnimate() {
        itemViews.forEach { $0.layer.removeAllAnimations() }
    }
    
    required init?(coder: NSCoder) {
        fatalError("init(coder:) has not been implemented")
    }
}

extension LNVoiceWaveView {
    private func setupViews() {
        isUserInteractionEnabled = false
        
        stackView.axis = .horizontal
        stackView.distribution = .equalSpacing
        stackView.alignment = .center
        addSubview(stackView)
        stackView.snp.makeConstraints { make in
            make.edges.equalToSuperview()
        }
    }
}


#if DEBUG

import SwiftUI

struct LNVoiceWaveViewPreview: UIViewRepresentable {
    func makeUIView(context: Context) -> some UIView {
        let container = UIView()
        container.backgroundColor = .lightGray
        
        let view = LNVoiceWaveView()
        view.fillColor = .red
        view.itemWidth = 10
        container.addSubview(view)
        view.snp.makeConstraints { make in
            make.center.equalToSuperview()
            make.height.equalTo(100)
            make.width.equalTo(150)
        }
        view.build()
        
        view.onTap {
            view.startAnimate()
        }
        
        return container
    }
    
    func updateUIView(_ uiView: UIViewType, context: Context) { }
}

#Preview(body: {
    LNVoiceWaveViewPreview()
})
#endif