//
//  SAConfettiView.swift
//  Pods
//
//  Created by Sudeep Agarwal on 12/14/15.
//
//

import UIKit
import QuartzCore

public class SAConfettiView: UIView, CAAnimationDelegate {
    
    public enum ConfettiType {
        case Confetti
        case Triangle
        case Star
        case Diamond
        case Image(UIImage)
    }
    
    var emitter: CAEmitterLayer!
    public var colors: [UIColor]!
    public var intensity: Float!
    public var type: ConfettiType!
    
    required public init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        setup()
    }
    
    public override init(frame: CGRect) {
        super.init(frame: frame)
        setup()
    }
    
    func setup() {
        colors = [UIColor(red:0.95, green:0.40, blue:0.27, alpha:1.0),
                  UIColor(red:1.00, green:0.78, blue:0.36, alpha:1.0),
                  UIColor(red:0.48, green:0.78, blue:0.64, alpha:1.0),
                  UIColor(red:0.30, green:0.76, blue:0.85, alpha:1.0),
                  UIColor(red:0.58, green:0.39, blue:0.55, alpha:1.0)]
        intensity = 0.5
        type = .Confetti
    }
    
    @objc public func startConfetti() -> Void {
        emitter = CAEmitterLayer()
        
        emitter.emitterPosition = CGPoint(x: self.center.x, y: 0)
        emitter.emitterShape = CAEmitterLayerEmitterShape.line
        emitter.emitterSize = CGSize(width: 40.0, height: 1)
        
        var cells = [CAEmitterCell]()
        for color in colors {
            cells.append(confettiWithColor(color: color))
        }
        
        emitter.emitterCells = cells
        layer.addSublayer(emitter)
        
        let animation = CAKeyframeAnimation(keyPath: "birthRate")
        animation.duration = 1
        animation.keyTimes = [0.5, 2.0]
        animation.values = [2.0, 0.0]
        animation.repeatCount = MAXFLOAT
        animation.delegate = self
        emitter.add(animation, forKey: "confettis")
    }
    
    override public func layoutSubviews() {
        super.layoutSubviews()
        
        emitter.emitterPosition = CGPoint(x: self.center.x, y: 0)
    }
    
    @objc public func stopConfetti() {
        emitter?.birthRate = 0
    }
    
    func imageForType(type: ConfettiType) -> UIImage? {
        
        var fileName: String!
        
        switch type {
        case .Confetti:
            fileName = "confetti"
        case .Triangle:
            fileName = "triangle"
        case .Star:
            fileName = "star"
        case .Diamond:
            fileName = "diamond"
        case let .Image(customImage):
            return customImage
        }
        
        
        return UIImage(imageLiteralResourceName: fileName)
    }
    
    func confettiWithColor(color: UIColor) -> CAEmitterCell {
        let confetti = CAEmitterCell()
        confetti.birthRate = 6.0 * intensity
        confetti.lifetime = 14.0 * intensity
        confetti.lifetimeRange = 0
        confetti.color = color.cgColor
        confetti.velocity = CGFloat(350.0 * intensity)
        confetti.velocityRange = CGFloat(80.0 * intensity)
        confetti.emissionLongitude = CGFloat(Double.pi)
        confetti.emissionRange = CGFloat(Double.pi / 4.0)
        confetti.spin = CGFloat(3.5 * intensity)
        confetti.spinRange = CGFloat(4.0 * intensity)
        confetti.scaleRange = CGFloat(intensity)
        confetti.scaleSpeed = CGFloat(-0.1 * intensity)
        confetti.contents = imageForType(type: type)!.cgImage
        return confetti
    }
    
}