feat: 实现下载，给出例子

src/main.rs

@@ -1,8 +1,11 @@
+use std::path::Path;
 use std::rc::Rc;
 
 use bili_sync::bilibili::{
-    AudioQuality, BiliClient, FavoriteList, Video, VideoCodecs, VideoQuality,
+    AudioQuality, BestStream, BiliClient, FavoriteList, FilterOption, Video, VideoCodecs,
+    VideoQuality,
 };
+use bili_sync::downloader::Downloader;
 use futures_util::{pin_mut, StreamExt};
 
 #[tokio::main]
@@ -10,36 +13,57 @@ async fn main() {
     let bili_client = Rc::new(BiliClient::anonymous());
     let favorite_list = FavoriteList::new(bili_client.clone(), "52642258".to_string());
     dbg!(favorite_list.get_info().await.unwrap());
+
     let video_stream = favorite_list.into_video_stream();
     // from doc: https://docs.rs/async-stream/latest/async_stream/
     pin_mut!(video_stream);
-    let mut count = 3;
-    let mut third_video = None;
-    while let Some(mut video) = video_stream.next().await {
-        count -= 1;
-        video = dbg!(video);
-        if count <= 0 {
-            third_video = Some(video);
-            break;
-        }
-    }
-    let third_video = Video::new(bili_client.clone(), third_video.unwrap().bvid);
+
+    let third_video_info = dbg!(video_stream.skip(2).next().await.unwrap());
+    let third_video = Video::new(bili_client.clone(), third_video_info.bvid);
     dbg!(third_video.get_tags().await.unwrap());
+
     let pages = dbg!(third_video.get_pages().await.unwrap());
-    dbg!(third_video
+    let best_stream = dbg!(third_video
         .get_page_analyzer(&pages[0])
         .await
         .unwrap()
-        .best_stream(
-            VideoQuality::QualityDolby,
-            VideoQuality::Quality360p,
-            AudioQuality::QualityDolby,
-            AudioQuality::Quality64k,
-            vec![VideoCodecs::HEV, VideoCodecs::AVC],
-            false,
-            false,
-            false,
-            false,
-        ))
+        .best_stream(&FilterOption {
+            video_max_quality: VideoQuality::QualityDolby,
+            video_min_quality: VideoQuality::Quality360p,
+            audio_max_quality: AudioQuality::QualityDolby,
+            audio_min_quality: AudioQuality::Quality64k,
+            codecs: Rc::new(vec![VideoCodecs::HEV, VideoCodecs::AVC]),
+            no_dolby_video: false,
+            no_dolby_audio: false,
+            no_hdr: false,
+            no_hires: false,
+        }))
     .unwrap();
+
+    let downloader = Downloader::default();
+    let base = Path::new("./");
+    let output_path = base.join(format!("{}.mp4", third_video_info.title));
+
+    match best_stream {
+        BestStream::Mixed(stream) => {
+            let url = dbg!(stream.url());
+            downloader.fetch(url, &output_path).await.unwrap();
+        }
+        BestStream::VideoAudio { video, audio } => {
+            let url = dbg!(video.url());
+            let Some(audio) = audio else {
+                downloader.fetch(url, &output_path).await.unwrap();
+                return;
+            };
+            let video_path = base.join(format!("{}_video_tmp", third_video_info.title));
+            downloader.fetch(url, &video_path).await.unwrap();
+            let url = dbg!(audio.url());
+            let audio_path = base.join(format!("{}_audio_tmp", third_video_info.title));
+            downloader.fetch(url, &audio_path).await.unwrap();
+            downloader
+                .merge(&video_path, &audio_path, &output_path)
+                .await
+                .unwrap();
+        }
+    }
 }