iOS播放已经下载，部分下载，没有下载的视频资源

1） 已经下载完毕，直接使用资源路径
2） 部分下载，使用资源路径，并开始下载
3） 没有下载，开始边下边播

    if ([ZFPlayerCacheManager isfinishedLoadedWithURL:urlString]) {
        ///已经下载完毕
        NSString *path = [[ZFPlayerCacheManager shareManager] diskCachePathForURL:urlString];
        mutedUrl = [NSURL fileURLWithPath:path];
    } else if ([ZFPlayerCacheManager hasDownLoadPartWithURL:urlString]) {
        // 只下载了一部分, 则需要继续下载
        NSString *path = [[ZFPlayerCacheManager shareManager] diskCachePathForURL:urlString];
        mutedUrl = [NSURL fileURLWithPath:path];
        [[ZFPlayerCacheManager shareManager] startDownWithUrl:assetURL downInfo:^(long long totalSize, NSHTTPURLResponse * _Nonnull response) {
        } progress:^(float progress) {
        }];
    } else {
        mutedUrl = [urlString urlScheme:@"streaming"];
        self.currentPlayerManager.loadResource = YES;
        NSURLComponents *components = [[NSURLComponents alloc] initWithURL:assetURL resolvingAgainstBaseURL:NO];
        self.currentPlayerManager.originalScheme = components.scheme;
    }
    self.assetURL = mutedUrl;