kylehowells · February 25, 2023 23:27 · Feb 25, 2023
diff --git a/WaveView.swift b/WaveView.swift
@@ -0,0 +1,112 @@
+import UIKit
+
+// MARK: - WaveView
+
+class WaveView: UIView {
+
+	private var shapeLayer: CAShapeLayer = CAShapeLayer()
+
+	// MARK: - Animation Properties
+
+	/// 0 - Static
+	/// 20 - Very fast
+	var speed: CGFloat = 10
+
+	/// Wave Height
+	var frequency: CGFloat = 6.0
+
+	/// Wave phase
+	private var phase: CGFloat = 0.0
+
+	/// Wave color
+	var preferredColor: UIColor = UIColor.cyan {
+		didSet {
+			self.shapeLayer.fillColor = self.preferredColor.cgColor
+			self.shapeLayer.strokeColor = self.preferredColor.cgColor
+		}
+	}
+
+	// MARK: - Start Animation
+
+	enum Direction {
+		case right
+		case left
+	}
+
+	func animationStart(direction: Direction, speed: Double) {
+		self.preferredColor = UIColor.cyan
+		self.layer.addSublayer(self.shapeLayer)
+
+		if direction == .right {
+			self.speed = -speed
+		} else {
+			self.speed = speed
+		}
+
+		self.startDisplayLink()
+	}
+
+
+	// MARK: - Display Link
+
+	private weak var displayLink: CADisplayLink?
+
+	private var startTime: CFTimeInterval = 0
+
+	private func startDisplayLink() {
+		self.startTime = CACurrentMediaTime()
+		self.displayLink?.invalidate()
+
+		let displayLink = CADisplayLink(target: self, selector:#selector(self.handleDisplayLink(_:)))
+		displayLink.add(to: .main, forMode: .common)
+		self.displayLink = displayLink
+	}
+
+	@objc private func handleDisplayLink(_ displayLink: CADisplayLink) {
+		self.phase = (CACurrentMediaTime() - self.startTime) * self.speed
+
+		self.updatePath()
+	}
+
+	private func stopDisplayLink() {
+		self.displayLink?.invalidate()
+	}
+
+
+	// MARK: - Layout
+
+	override func layoutSubviews() {
+		super.layoutSubviews()
+
+		self.shapeLayer.frame = self.bounds
+		self.updatePath()
+	}
+
+	func updatePath() {
+		let path: UIBezierPath = UIBezierPath()
+		let width: CGFloat = self.bounds.width
+		let height: CGFloat = self.bounds.height
+
+		let mid: CGFloat = height * 0.25
+
+		let waveLength: CGFloat = width / self.frequency
+		let waveHeightCoef: CGFloat = self.frequency
+
+		path.move(to: CGPoint(x: 0, y: self.bounds.maxY))
+		path.addLine(to: CGPoint(x: 0, y: mid))
+
+		for x in stride(from: 0, through: width, by: 1)
+		{
+			let actualX: CGFloat = x / waveLength
+			let sine: CGFloat = -sin((actualX + self.phase))
+
+			let y: CGFloat = waveHeightCoef * sine + mid
+			path.addLine(to: CGPoint(x: x, y: y))
+		}
+
+		path.addLine(to: CGPoint(x: CGFloat(width), y: self.bounds.maxY))
+		path.addLine(to: CGPoint(x: 0, y: self.bounds.maxY))
+
+		self.shapeLayer.path = path.cgPath
+	}
+}