Fix aggressive thumb preload

https://github.com/coil-kt/coil/commit/65ff90ea2b11db9da98cc7763d9c5f60e9ca364a

app/src/main/java/com/hippo/ehviewer/coil/Extensions.kt

@@ -1,7 +1,12 @@
 package com.hippo.ehviewer.coil
 
 import android.content.Context
+import android.graphics.Color
+import android.graphics.drawable.ColorDrawable
+import coil.decode.DecodeResult
+import coil.decode.Decoder
 import coil.disk.DiskCache
+import coil.request.CachePolicy
 import coil.request.ImageRequest
 import coil.size.Size
 import com.hippo.ehviewer.client.data.GalleryPreview
@@ -25,6 +30,11 @@ fun ImageRequest.Builder.ehPreviewKey(key: GalleryPreview) = apply {
     size(Size.ORIGINAL)
 }
 
+fun ImageRequest.Builder.justDownload() = apply {
+    memoryCachePolicy(CachePolicy.DISABLED)
+    decoderFactory { _, _, _ -> Decoder { DecodeResult(ColorDrawable(Color.BLACK), false) } }
+}
+
 inline fun Context.imageRequest(key: GalleryPreview, builder: ImageRequest.Builder.() -> Unit = {}) = ImageRequest.Builder(this).ehPreviewKey(key).apply(builder).build()
 inline fun Context.imageRequest(key: String?, builder: ImageRequest.Builder.() -> Unit = {}) = ImageRequest.Builder(this).ehUrl(key).apply(builder).build()
 inline fun diskCache(builder: DiskCache.Builder.() -> Unit) = DiskCache.Builder().apply(builder).build()

app/src/main/java/com/hippo/ehviewer/ui/scene/GalleryDetailScene.kt

@@ -139,6 +139,7 @@ import com.hippo.ehviewer.client.parser.HomeParser
 import com.hippo.ehviewer.client.parser.ParserUtils
 import com.hippo.ehviewer.client.parser.TorrentParser
 import com.hippo.ehviewer.coil.imageRequest
+import com.hippo.ehviewer.coil.justDownload
 import com.hippo.ehviewer.dao.DownloadInfo
 import com.hippo.ehviewer.dao.Filter
 import com.hippo.ehviewer.download.DownloadManager.DownloadInfoListener
@@ -892,11 +893,7 @@ class GalleryDetailScene : BaseScene(), DownloadInfoListener {
                 EhDB.putHistoryInfo(galleryDetail)
                 if (Settings.preloadThumbAggressively) {
                     lifecycleScope.launchIO {
-                        galleryDetail.previewList.forEach {
-                            context?.run {
-                                imageLoader.enqueue(imageRequest(it))
-                            }
-                        }
+                        galleryDetail.previewList.forEach { context?.run { imageLoader.enqueue(imageRequest(it) { justDownload() }) } }
                     }
                 }
                 composeBindingGD = galleryDetail

app/src/main/java/com/hippo/ehviewer/ui/scene/GalleryListScene.kt

@@ -71,6 +71,7 @@ import com.hippo.ehviewer.client.parser.GalleryDetailUrlParser
 import com.hippo.ehviewer.client.parser.GalleryListParser
 import com.hippo.ehviewer.client.parser.GalleryPageUrlParser
 import com.hippo.ehviewer.coil.imageRequest
+import com.hippo.ehviewer.coil.justDownload
 import com.hippo.ehviewer.dao.DownloadInfo
 import com.hippo.ehviewer.dao.QuickSearch
 import com.hippo.ehviewer.databinding.DrawerListRvBinding
@@ -1052,11 +1053,7 @@ class GalleryListScene : SearchBarScene(), OnDragHandlerListener, SearchLayout.H
     private fun onGetGalleryListSuccess(result: GalleryListParser.Result, taskId: Int) {
         if (Settings.preloadThumbAggressively) {
             lifecycleScope.launchIO {
-                result.galleryInfoList.forEach {
-                    context?.run {
-                        imageLoader.enqueue(imageRequest(it.thumb))
-                    }
-                }
+                result.galleryInfoList.forEach { context?.run { imageLoader.enqueue(imageRequest(it.thumb) { justDownload() }) } }
             }
         }
         if (mHelper != null && mHelper!!.isCurrentTask(taskId)) {

app/src/main/java/com/hippo/ehviewer/ui/scene/GalleryPreviewScreen.kt

@@ -54,6 +54,7 @@ import com.hippo.ehviewer.client.EhUrl
 import com.hippo.ehviewer.client.data.GalleryDetail
 import com.hippo.ehviewer.client.data.GalleryPreview
 import com.hippo.ehviewer.coil.imageRequest
+import com.hippo.ehviewer.coil.justDownload
 import com.hippo.ehviewer.ui.compose.data.EhPreviewItem
 import com.hippo.ehviewer.ui.compose.rememberDialogState
 import com.hippo.ehviewer.ui.compose.setMD3Content
@@ -90,7 +91,7 @@ class GalleryPreviewScreen : Fragment() {
                     val result = EhEngine.getPreviewList(url)
                     if (Settings.preloadThumbAggressively) {
                         coroutineScope.launch {
-                            context.run { result.first.first.forEach { imageLoader.enqueue(imageRequest(it)) } }
+                            context.run { result.first.first.forEach { imageLoader.enqueue(imageRequest(it) { justDownload() }) } }
                         }
                     }
                     result.first.first