import UIKit
import AVFoundation

class ViewController: UIViewController {

    lazy var player: AVAudioPlayer? = {
        // 1. 创建播放器(NSURL, 只能是本地URL 地址, 远程音乐, 使用这个类, 播放不了)
        let url = Bundle.main.url(forResource: "简单爱.mp3", withExtension: nil)
       
        do {
            
            let player = try AVAudioPlayer(contentsOf: url!)
            
            player.delegate = self
            
            
            // 设置可以速率播放
            player.enableRate = true
            
            // 准备播放
            player.prepareToPlay()
            // 开始播放
            //player.play()
            return player
            
        }catch {
            print(error)
            return nil
        }
        

    }()
    
    
    func playBack() -> () {
        
        // 1. 获取音频会话
        let audioSession: AVAudioSession = AVAudioSession.sharedInstance()
        
        do {
            // 2. 设置会话类型
            if #available(iOS 10.0, *) {
                try audioSession.setCategory(.playback, mode: .default, options: .defaultToSpeaker)
            } else {
                // Fallback on earlier versions
            }
            
            // 3. 激活会话
            try audioSession.setActive(true)
            
        }catch {
            print(error)
        }
        
        
    }
    
    
    @IBAction func play() {
         playBack()
        player?.play()
        
    }
    @IBAction func pause() {
        
        player?.pause()
        
        
    }
    @IBAction func stop() {
        
        // 重置当前播放事件
        player?.currentTime = 0
        player?.stop()
        
    }
    
    @IBAction func kuaijin() {
        
        // 这个值, 自动会做好容错适配, 不需要我们处理, 负数, 或者, 大于最大播放时长的数值
        player?.currentTime += 15
        
    }
    
    @IBAction func kuaitui() {
        
        player?.currentTime -= 15
        
    }
    
    @IBAction func ratePlay() {
        
        player?.rate = 10.0
        
    }
    
    @IBAction func volumn(sender: UISlider) {
        
        player?.volume = sender.value
        
    }
    

}


extension ViewController: AVAudioPlayerDelegate {
    
    
    func audioPlayerDidFinishPlaying(_ player: AVAudioPlayer, successfully flag: Bool) {
        print("播放完成")
    }
    
    
}