Add delay after download to reduce download speed

app/build.gradle

@@ -27,7 +27,7 @@ android {
         applicationId "com.hippo.ehviewer"
         minSdkVersion 21
         targetSdkVersion 30
-        versionCode 107
+        versionCode 108
         versionName "1.7.6"
         resConfigs "zh", "zh-rCN", "zh-rHK", "zh-rTW",
                 "es", "ja", "ko", "fr", "de", "th"

app/src/main/java/com/hippo/ehviewer/Settings.java

@@ -257,6 +257,8 @@ public class Settings {
     private static final boolean DEFAULT_GUIDE_GALLERY = true;
     private static final String KEY_CLIPBOARD_TEXT_HASH_CODE = "clipboard_text_hash_code";
     private static final int DEFAULT_CLIPBOARD_TEXT_HASH_CODE = 0;
+    private static final String KEY_DOWNLOAD_DELAY = "download_delay";
+    private static final int DEFAULT_DOWNLOAD_DELAY = 0;
     private static Context sContext;
     private static SharedPreferences sSettingsPre;
     private static EhConfig sEhConfig;
@@ -740,6 +742,14 @@ public class Settings {
         putIntToStr(KEY_MULTI_THREAD_DOWNLOAD, value);
     }
 
+    public static int getDownloadDelay() {
+        return getIntFromStr(KEY_DOWNLOAD_DELAY, DEFAULT_DOWNLOAD_DELAY);
+    }
+
+    public static void putDownloadDelay(int value) {
+        putIntToStr(KEY_DOWNLOAD_DELAY, value);
+    }
+
     public static int getPreloadImage() {
         return getIntFromStr(KEY_PRELOAD_IMAGE, DEFAULT_PRELOAD_IMAGE);
     }

app/src/main/java/com/hippo/ehviewer/spider/SpiderQueen.java

@@ -143,6 +143,7 @@ public final class SpiderQueen implements Runnable {
     private final int mPreloadNumber;
     private int mReadReference = 0;
     private int mDownloadReference = 0;
+    private final int mDownloadDelay;
     // It mQueenThread is null, failed or stopped
     @Nullable
     private volatile Thread mQueenThread;
@@ -169,6 +170,7 @@ public final class SpiderQueen implements Runnable {
         mWorkerPoolExecutor = new ThreadPoolExecutor(mWorkerMaxCount, mWorkerMaxCount,
                 0, TimeUnit.SECONDS, new LinkedBlockingDeque<>(),
                 new PriorityThreadFactory(SpiderWorker.class.getSimpleName(), Process.THREAD_PRIORITY_BACKGROUND));
+        mDownloadDelay = Settings.getDownloadDelay();
     }
 
     @UiThread
@@ -1349,6 +1351,11 @@ public final class SpiderQueen implements Runnable {
 
                     // Download finished
                     updatePageState(index, STATE_FINISHED);
+                    try {
+                        Thread.sleep(mDownloadDelay);
+                    } catch (InterruptedException e) {
+                        e.printStackTrace();
+                    }
                     return true;
                 } catch (IOException e) {
                     e.printStackTrace();

app/src/main/res/values-zh-rCN/strings.xml

@@ -716,4 +716,6 @@
     <string name="download_filter">过滤</string>
     <string name="download_all">全部</string>
     <string name="download_start_all_reversed">全部开始（倒序）</string>
+    <string name="settings_download_download_delay">下载延时</string>
+    <string name="settings_download_download_delay_summary">每次下载延时 %s 毫秒</string>
 </resources>

app/src/main/res/values/arrays.xml

@@ -115,6 +115,28 @@
         <item>7</item>
     </string-array>
 
+    <string-array name="download_delay_entries" translatable="false">
+        <item>0</item>
+        <item>500</item>
+        <item>1000</item>
+        <item>1500</item>
+        <item>2000</item>
+        <item>3000</item>
+        <item>10000</item>
+        <item>20000</item>
+    </string-array>
+
+    <string-array name="download_delay_entry_values" translatable="false">
+        <item>0</item>
+        <item>500</item>
+        <item>1000</item>
+        <item>1500</item>
+        <item>2000</item>
+        <item>3000</item>
+        <item>10000</item>
+        <item>20000</item>
+    </string-array>
+
     <string-array name="preload_image_entries" translatable="false">
         <item>3</item>
         <item>5</item>

app/src/main/res/values/strings.xml

@@ -554,6 +554,8 @@
     <string name="settings_download_media_scan_summary_off">Most gallery apps will ignore pictures in the download path</string>
     <string name="settings_download_multi_thread_download">Multi-threaded download</string>
     <string name="settings_download_multi_thread_download_summary">Up to %s images</string>
+    <string name="settings_download_download_delay">Download delay</string>
+    <string name="settings_download_download_delay_summary">Delay %s ms per download</string>
     <string name="settings_download_preload_image">Preload image</string>
     <string name="settings_download_preload_image_summary">Preload next %s image</string>
     <string name="settings_download_image_resolution">Image resolution</string>

app/src/main/res/xml/download_settings.xml

@@ -39,6 +39,15 @@
         app:entryValues="@array/multi_thread_download_entry_values"
         app:iconSpaceReserved="false" />
 
+    <SimpleMenuPreference
+        android:key="download_delay"
+        android:title="@string/settings_download_download_delay"
+        android:summary="@string/settings_download_download_delay_summary"
+        app:entries="@array/download_delay_entries"
+        app:entryValues="@array/download_delay_entry_values"
+        android:defaultValue="0"
+        app:iconSpaceReserved="false" />
+
     <SimpleMenuPreference
         android:defaultValue="5"
         android:key="preload_image"