refactor: replace RxDownload with my own implementation

app/src/main/java/com/stardust/scriptdroid/network/api/DownloadApi.java

@@ -0,0 +1,19 @@
+package com.stardust.scriptdroid.network.api;
+
+import io.reactivex.Observable;
+import okhttp3.ResponseBody;
+import retrofit2.http.GET;
+import retrofit2.http.Streaming;
+import retrofit2.http.Url;
+
+/**
+ * Created by Stardust on 2017/12/6.
+ */
+
+public interface DownloadApi {
+
+    @GET
+    @Streaming
+    Observable<ResponseBody> download(@Url String url);
+
+}

app/src/main/java/com/stardust/scriptdroid/network/download/DownloadManager.java

@@ -1,17 +1,24 @@
 package com.stardust.scriptdroid.network.download;
 
-import android.content.Context;
+import com.jakewharton.retrofit2.adapter.rxjava2.RxJava2CallAdapterFactory;
+import com.stardust.concurrent.VolatileBox;
+import com.stardust.scriptdroid.network.NodeBB;
+import com.stardust.scriptdroid.network.api.DownloadApi;
 
-import java.io.File;
+import java.io.FileOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
 import java.net.URLDecoder;
+import java.util.concurrent.ConcurrentHashMap;
 
 import io.reactivex.Observable;
+import io.reactivex.schedulers.Schedulers;
 import io.reactivex.subjects.PublishSubject;
-import retrofit2.http.Url;
-import zlc.season.rxdownload3.RxDownload;
-import zlc.season.rxdownload3.core.Failed;
-import zlc.season.rxdownload3.core.Mission;
-import zlc.season.rxdownload3.core.Succeed;
+import okhttp3.OkHttpClient;
+import okhttp3.Request;
+import okhttp3.Response;
+import okhttp3.ResponseBody;
+import retrofit2.Retrofit;
 
 /**
  * Created by Stardust on 2017/10/20.
@@ -21,16 +28,36 @@ public class DownloadManager {
 
     private static DownloadManager sInstance;
 
-    private Context mContext;
+    private static final int RETRY_COUNT = 3;
+    private Retrofit mRetrofit;
+    private DownloadApi mDownloadApi;
+    private ConcurrentHashMap<String, VolatileBox<Boolean>> mDownloadStatuses = new ConcurrentHashMap<>();
 
-
-    public DownloadManager(Context context) {
-        mContext = context;
+    public DownloadManager() {
+        mRetrofit = new Retrofit.Builder()
+                .baseUrl(NodeBB.BASE_URL)
+                .addCallAdapterFactory(RxJava2CallAdapterFactory.create())
+                .client(new OkHttpClient.Builder()
+                        .addInterceptor(chain -> {
+                            Request request = chain.request();
+                            Response response = chain.proceed(request);
+                            int tryCount = 0;
+                            while (!response.isSuccessful() && tryCount < RETRY_COUNT) {
+                                tryCount++;
+                                response = chain.proceed(request);
+                            }
+                            return response;
+                        })
+                        .build()
+                )
+                .build();
+        mDownloadApi = mRetrofit.create(DownloadApi.class);
     }
 
-    public static DownloadManager getInstance(Context context) {
+
+    public static DownloadManager getInstance() {
         if (sInstance == null) {
-            sInstance = new DownloadManager(context);
+            sInstance = new DownloadManager();
         }
         return sInstance;
     }
@@ -45,28 +72,89 @@ public class DownloadManager {
     }
 
     public Observable<Integer> download(String url, String path) {
-        File file = new File(path);
-        Mission mission = new Mission(url, file.getName(), file.getParent());
-        PublishSubject<Integer> progress = PublishSubject.create();
-        RxDownload.INSTANCE.create(mission)
-                .subscribe(status -> {
-                    if (status.getTotalSize() > 0) {
-                        int p = (int) Math.floor((float) status.getDownloadSize() / status.getTotalSize() * 100);
-                        progress.onNext(p);
-                    }
-                    if (status instanceof Succeed) {
-                        progress.onComplete();
-                        RxDownload.INSTANCE.delete(mission);
-                    } else if (status instanceof Failed) {
-                        progress.onError(((Failed) status).getThrowable());
-                    }
-                });
-        RxDownload.INSTANCE.start(mission).subscribe();
-        return progress;
+        DownloadTask task = new DownloadTask(url, path);
+        mDownloadApi.download(url)
+                .subscribeOn(Schedulers.io())
+                .subscribe(task::start);
+        return task.progress();
     }
 
     public void cancelDownload(String url) {
-        RxDownload.INSTANCE.stop(url);
-        RxDownload.INSTANCE.delete(url);
+        VolatileBox<Boolean> status = mDownloadStatuses.get(url);
+        if (status != null) {
+            status.set(false);
+        }
+    }
+
+    private class DownloadTask {
+
+        private String mUrl;
+        private String mPath;
+        private VolatileBox<Boolean> mStatus;
+        private InputStream mInputStream;
+        private FileOutputStream mFileOutputStream;
+        private PublishSubject<Integer> mProgress;
+
+        public DownloadTask(String url, String path) {
+            mUrl = url;
+            mPath = path;
+            mStatus = new VolatileBox<>(true);
+            VolatileBox<Boolean> previous = mDownloadStatuses.put(mUrl, mStatus);
+            if (previous != null)
+                previous.set(false);
+            mProgress = PublishSubject.create();
+        }
+
+        public void start(ResponseBody body) throws IOException {
+            byte[] buffer = new byte[4096];
+            mFileOutputStream = new FileOutputStream(mPath);
+            mInputStream = body.byteStream();
+            long total = body.contentLength();
+            long read = 0;
+            while (read < total) {
+                if (!mStatus.get()) {
+                    onCancel();
+                    return;
+                }
+                int len = mInputStream.read(buffer);
+                if (len == -1) {
+                    break;
+                }
+                read += len;
+                mFileOutputStream.write(buffer, 0, len);
+                mProgress.onNext((int) (100 * read / total));
+            }
+            mProgress.onComplete();
+            recycle();
+        }
+
+        private void onCancel() throws IOException {
+            recycle();
+            // TODO: 2017/12/6 notify?
+        }
+
+        public void recycle() {
+            mDownloadStatuses.remove(mUrl);
+            if (mInputStream != null) {
+                try {
+                    mInputStream.close();
+                } catch (IOException ignored) {
+
+                }
+            }
+            if (mFileOutputStream != null) {
+                try {
+                    mFileOutputStream.close();
+                } catch (IOException ignored) {
+                }
+            }
+
+        }
+
+        public Observable<Integer> progress() {
+            return mProgress;
+        }
+
+
     }
 }

app/src/main/java/com/stardust/scriptdroid/ui/common/ScriptOperations.java

@@ -265,13 +265,13 @@ public class ScriptOperations {
                 .title(fileName)
                 .cancelable(false)
                 .positiveText(R.string.text_cancel_download)
-                .onPositive((dialog, which) -> DownloadManager.getInstance(mContext).cancelDownload(url))
+                .onPositive((dialog, which) -> DownloadManager.getInstance().cancelDownload(url))
                 .show();
     }
 
     public Observable<ScriptFile> download(String url, String path, MaterialDialog progressDialog) {
         PublishSubject<ScriptFile> subject = PublishSubject.create();
-        DownloadManager.getInstance(mContext).download(url, path)
+        DownloadManager.getInstance().download(url, path)
                 .observeOn(AndroidSchedulers.mainThread())
                 .doOnNext(progressDialog::setProgress)
                 .doOnComplete(() -> {

app/src/main/java/com/stardust/scriptdroid/ui/main/MainActivity.java

@@ -27,6 +27,7 @@ import com.stardust.scriptdroid.Pref;
 import com.stardust.scriptdroid.R;
 import com.stardust.scriptdroid.autojs.AutoJs;
 import com.stardust.scriptdroid.ui.common.NotAskAgainDialog;
+import com.stardust.scriptdroid.ui.common.ScriptOperations;
 import com.stardust.scriptdroid.ui.doc.DocsFragment_;
 import com.stardust.scriptdroid.ui.floating.FloatyWindowManger;
 import com.stardust.scriptdroid.storage.file.StorageFileProvider;