using NAudio.Wave;
using Qing.Lang;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace QingLib {
    public class LibObj : Obj {

        public LibObj() : base() {

            Map["@播放音乐"] = new Expr(new PlaySound());
        }

        class PlaySound : Native {
            public override string Name { get; set; } = "播放音乐";
            public override string Desc { get; set; } = "参数1-字符串，可选参数2-逻辑，返回对象；打开参数1对应的音乐文件，默认立即播放，若传入参数2，并且为真，则不立即播放";
            public override Expr Run(List<Expr> args, Ctx ctx, Obj? obj=null, List<Expr>? namedArgs=null) {
                if (args.Count == 0) {
                    return Expr.Err("播放音乐函数需要文件路径参数");
                }
                if (args[0].Tp != TP.Str) {
                    return Expr.Err("播放音乐的文件路径参数必须是字符串类型");
                }

                string file = args[0].Str();
                if (!file.StartsWith("/") && !file.Contains(":")) {
                    file = Directory.GetCurrentDirectory() + "/" + file;
                }
                if (!File.Exists(file)) {
                    return Expr.Err("要打开的音乐文件不存在");
                }

                bool wt = false;
                if(args.Count > 1) {
                    wt = args[1].ToBool();
                }

                SoundDriver soundDriver = new SoundDriver();
                Task.Run(async () => {
                    soundDriver.audioFile = new AudioFileReader(file);
                    using (var outputDevice = new WaveOutEvent()) {
                        soundDriver.Raw = outputDevice;
                        soundDriver.currFile = file;
                        outputDevice.Init(soundDriver.audioFile);
                        if (wt) {
                            outputDevice.Pause();
                        } else {
                            outputDevice.Play();
                        }

                        while (outputDevice.PlaybackState != PlaybackState.Stopped) {
                            await Task.Delay(500);
                        }
                        if (outputDevice.PlaybackState == PlaybackState.Stopped) {
                            try {
                                if (soundDriver.audioFile != null) {
                                    soundDriver.audioFile.Close();
                                    soundDriver.audioFile = null;
                                }
                            } catch (Exception ex) {
                                Console.WriteLine(ex.Message);
                            }
                        }
                    }
                });

                while (soundDriver.Raw is not WaveOutEvent) {
                    Thread.Sleep(20);
                }

                return new Expr(TP.Obj, soundDriver);
            }

        }



    }
}