YooAsset/Assets/YooAsset/Runtime/BundleCache/Services/WebServerBundleCache/Operations/WSBCLoadBundleOperation.cs

namespace YooAsset
{
    /// <summary>
    /// Web服务器文件缓存加载 AssetBundle 操作
    /// </summary>
    internal class WSBCLoadAssetBundleOperation : BCLoadBundleOperation
    {
        private enum ESteps
        {
            None,
            GetEntry,
            LoadBundle,
            Done,
        }

        private readonly WebServerBundleCache _fileCache;
        private readonly BCLoadBundleOptions _options;
        private LoadWebAssetBundleOperation _loadWebAssetBundleOp;
        private WebServerBundleCacheEntry _cacheEntry;
        private ESteps _steps = ESteps.None;

        public WSBCLoadAssetBundleOperation(WebServerBundleCache fileCache, BCLoadBundleOptions options)
        {
            _fileCache = fileCache;
            _options = options;
        }
        protected override void InternalStart()
        {
            _steps = ESteps.GetEntry;
        }
        protected override void InternalUpdate()
        {
            if (_steps == ESteps.None || _steps == ESteps.Done)
                return;

            if (_steps == ESteps.GetEntry)
            {
                _cacheEntry = _fileCache.GetEntry(_options.Bundle.BundleGuid);
                if (_cacheEntry == null)
                {
                    _steps = ESteps.Done;
                    SetError($"File cache entry not found: '{_options.Bundle.BundleGuid}'.");
                }
                else
                {
                    _steps = ESteps.LoadBundle;
                }
            }

            if (_steps == ESteps.LoadBundle)
            {
                if (_loadWebAssetBundleOp == null)
                {
                    string url = DownloadUrlHelper.ToLocalFileUrl(_cacheEntry.FilePath);
                    var options = new LoadWebAssetBundleOptions();
                    options.CacheName = _fileCache.GetType().Name;
                    options.Bundle = _options.Bundle;
                    options.CandidateUrls = new[] { url };
                    options.AssetBundleDecryptor = _fileCache.Config.AssetBundleDecryptor;
                    options.DownloadBackend = _fileCache.Config.DownloadBackend;
                    options.DownloadVerifyLevel = _fileCache.Config.DownloadVerifyLevel;
                    options.WatchdogTimeout = _fileCache.Config.WatchdogTimeout;
                    options.DisableUnityWebCache = _fileCache.Config.DisableUnityWebCache;
                    options.DownloadRetryPolicy = _fileCache.Config.DownloadRetryPolicy;
                    options.DownloadUrlPolicy = _fileCache.Config.DownloadUrlPolicy;

                    if (_options.Bundle.IsEncrypted)
                        _loadWebAssetBundleOp = new LoadWebEncryptedAssetBundleOperation(options);
                    else
                        _loadWebAssetBundleOp = new LoadWebNormalAssetBundleOperation(options);

                    _loadWebAssetBundleOp.StartOperation();
                    AddChildOperation(_loadWebAssetBundleOp);
                }

                _loadWebAssetBundleOp.UpdateOperation();
                if (_loadWebAssetBundleOp.IsDone == false)
                    return;

                if (_loadWebAssetBundleOp.Status == EOperationStatus.Succeeded)
                {
                    if (_loadWebAssetBundleOp.BundleHandle == null)
                        throw new YooInternalException("Loaded bundle handle is null.");

                    _steps = ESteps.Done;
                    SetResult();
                    BundleHandle = _loadWebAssetBundleOp.BundleHandle;
                }
                else
                {
                    _steps = ESteps.Done;
                    SetError(_loadWebAssetBundleOp.Error);
                }
            }
        }
        protected override void InternalWaitForCompletion()
        {
            if (_steps != ESteps.Done)
            {
                _steps = ESteps.Done;
                SetError($"{nameof(WebServerBundleCache)} does not support synchronous asset bundle loading.");
                YooLogger.Error(Error);
            }
        }
    }
}