using XGame.Framework.Asyncs;
using System;
using UnityEngine.Networking;

namespace XGame.Framework.FileSystem
{
    //internal enum ECopyMode
    //{
    //    /// <summary>
    //    /// 包外->包外
    //    /// </summary>
    //    OUTSIDE_TO_OUTSIDE,
    //    /// <summary>
    //    /// 包内->包外
    //    /// </summary>
    //    INNERASSETS_TO_OUTSIDE
    //}

    internal sealed class CopyFileAsync : Async, ICopyFileAsync
    {
        bool overwrite;
        public bool Success { get; private set; }
        public string From { get; private set; }
        public string To { get; private set; }


        public CopyFileAsync(string source, string destination, bool overwrite)
        {
            From = source;
            To = destination;
            Success = false;
            this.overwrite = overwrite;
        }



        public void Start()
        {
            if (string.IsNullOrEmpty(From))
            {
                Success = false;
                Exception = new Exception($"源文件路径为空...");
                Completed();
                return;
            }
            WebRequestCopyFile();
        }
        private void WebRequestCopyFile()
        {
            var uri = new Uri(From);
            var request = UnityWebRequest.Get(uri);
            var operation = request.SendWebRequest();
            operation.completed += (op) =>
            {
                var bRet = request.result == UnityWebRequest.Result.Success && string.IsNullOrEmpty(request.error);
                if (bRet)
                {
                    try
                    {
                        var toDir = System.IO.Path.GetDirectoryName(To);
                        if (!System.IO.Directory.Exists(toDir))
                        {
                            System.IO.Directory.CreateDirectory(toDir);
                        }
                        System.IO.File.WriteAllBytes(To, request.downloadHandler.data);
                    }
                    catch (Exception ex)
                    {
                        OnThreadCompleted(new CopyThreadContext(false, ex));
                        return;
                    }
                }
                else
                {
                    Log.Error($"CopyFileAsync failed. From:{From} To:{To} UnityWebRequest Result:{request.result} Error:{request.error}");
                }
                OnThreadCompleted(new CopyThreadContext(bRet, null));
            };
        }

        private void OnThreadCompleted(object obj)
        {
            var context = (CopyThreadContext)obj;
            Exception = context.Exception;
            Success = context.Success;
            Completed();
        }



        struct CopyThreadContext
        {
            public bool Success { get; }
            public Exception Exception { get; }

            public CopyThreadContext(bool success, Exception exception)
            {
                Success = success;
                Exception = exception;
            }
        }
    }
}