Fix Cover sharing and saving (#5335)

* Fix Cover sharing and saving

The newly added manga cover sharing only worked with manga saved to the library (due to the implemented CoverCache only recording covers of library manga).
The changes made with this commit fixes that behaviour by implementing a fallback: the cover can now also be retrieved from the Coil memoryCache.

* Removal of coil MemoryKey usage

No longer uses the coil memory key, instead starts a new Coil request for the cover retrieval.

* Removed try-/catch-wrapper and added context-passing

useCoverAsBitmap lost its try-/catch-wrapper and doesn't call for the context anymore.
Instead shareCover and saveCover now pass their activity as context to useCoverAsBitmap.

* Added missing parameter description for useCoverAsBitmap

app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaController.kt

@@ -3,7 +3,10 @@ package eu.kanade.tachiyomi.ui.manga
 import android.animation.Animator
 import android.animation.AnimatorListenerAdapter
 import android.app.Activity
+import android.content.Context
 import android.content.Intent
+import android.graphics.Bitmap
+import android.graphics.drawable.BitmapDrawable
 import android.os.Bundle
 import android.view.LayoutInflater
 import android.view.Menu
@@ -20,6 +23,8 @@ import androidx.core.view.isVisible
 import androidx.recyclerview.widget.ConcatAdapter
 import androidx.recyclerview.widget.LinearLayoutManager
 import androidx.recyclerview.widget.RecyclerView
+import coil.imageLoader
+import coil.request.ImageRequest
 import com.bluelinelabs.conductor.ControllerChangeHandler
 import com.bluelinelabs.conductor.ControllerChangeType
 import com.google.android.material.floatingactionbutton.ExtendedFloatingActionButton
@@ -661,12 +666,35 @@ class MangaController :
         }
     }
 
+    /**
+     * Fetches the cover with Coil, turns it into Bitmap and does something with it (asynchronous)
+     * @param context The context for building and executing the ImageRequest
+     * @param coverHandler A function that describes what should be done with the Bitmap
+     */
+    private fun useCoverAsBitmap(context: Context, coverHandler: (Bitmap) -> Unit) {
+        val req = ImageRequest.Builder(context)
+            .data(manga)
+            .target { result ->
+                val coverBitmap = (result as BitmapDrawable).bitmap
+                coverHandler(coverBitmap)
+            }
+            .build()
+        context.imageLoader.enqueue(req)
+    }
+
     fun shareCover() {
         try {
             val activity = activity!!
-            val cover = presenter.shareCover(activity)
-            val uri = cover.getUriCompat(activity)
-            startActivity(Intent.createChooser(uri.toShareIntent(), activity.getString(R.string.action_share)))
+            useCoverAsBitmap(activity) { coverBitmap ->
+                val cover = presenter.shareCover(activity, coverBitmap)
+                val uri = cover.getUriCompat(activity)
+                startActivity(
+                    Intent.createChooser(
+                        uri.toShareIntent(),
+                        activity.getString(R.string.action_share)
+                    )
+                )
+            }
         } catch (e: Exception) {
             Timber.e(e)
             activity?.toast(R.string.error_sharing_cover)
@@ -675,8 +703,11 @@ class MangaController :
 
     fun saveCover() {
         try {
-            presenter.saveCover(activity!!)
-            activity?.toast(R.string.cover_saved)
+            val activity = activity!!
+            useCoverAsBitmap(activity) { coverBitmap ->
+                presenter.saveCover(activity, coverBitmap)
+                activity.toast(R.string.cover_saved)
+            }
         } catch (e: Exception) {
             Timber.e(e)
             activity?.toast(R.string.error_saving_cover)

app/src/main/java/eu/kanade/tachiyomi/ui/manga/MangaPresenter.kt

@@ -1,8 +1,12 @@
 package eu.kanade.tachiyomi.ui.manga
 
 import android.content.Context
+import android.graphics.Bitmap
+import android.graphics.BitmapFactory
 import android.net.Uri
 import android.os.Bundle
+import coil.imageLoader
+import coil.memory.MemoryCache
 import com.jakewharton.rxrelay.PublishRelay
 import eu.kanade.tachiyomi.data.cache.CoverCache
 import eu.kanade.tachiyomi.data.database.DatabaseHelper
@@ -280,29 +284,85 @@ class MangaPresenter(
         moveMangaToCategories(manga, listOfNotNull(category))
     }
 
-    fun shareCover(context: Context): File {
-        return saveCover(getTempShareDir(context))
+    /**
+     * Get the manga cover as a Bitmap, either from the CoverCache (only works for library manga)
+     * or from the Coil ImageLoader cache.
+     *
+     * @param context the context used to get the Coil ImageLoader
+     * @param memoryCacheKey Coil MemoryCache.Key that points to the cover Bitmap cache location
+     * @return manga cover as Bitmap
+     */
+    fun getCoverBitmap(context: Context, memoryCacheKey: MemoryCache.Key?): Bitmap {
+        var resultBitmap = coverBitmapFromCoverCache()
+        if (resultBitmap == null && memoryCacheKey != null) {
+            resultBitmap = coverBitmapFromImageLoader(context, memoryCacheKey)
+        }
+
+        return resultBitmap ?: throw Exception("Cover not in cache")
     }
 
-    fun saveCover(context: Context) {
-        saveCover(getPicturesDir(context))
+    /**
+     * Attempt manga cover retrieval from the CoverCache.
+     *
+     * @return cover as Bitmap or null if CoverCache does not contain cover for manga
+     */
+    private fun coverBitmapFromCoverCache(): Bitmap? {
+        val cover = coverCache.getCoverFile(manga)
+        return if (cover != null) {
+            BitmapFactory.decodeFile(cover.path)
+        } else {
+            null
+        }
     }
 
-    private fun saveCover(directory: File): File {
-        val cover = coverCache.getCoverFile(manga) ?: throw Exception("Cover url was null")
-        if (!cover.exists()) throw Exception("Cover not in cache")
-        val type = ImageUtil.findImageType(cover.inputStream())
-            ?: throw Exception("Not an image")
+    /**
+     * Attempt manga cover retrieval from the Coil ImageLoader memoryCache.
+     *
+     * @param context the context used to get the Coil ImageLoader
+     * @param memoryCacheKey Coil MemoryCache.Key that points to the cover Bitmap cache location
+     * @return cover as Bitmap or null if there is no thumbnail cached with the memoryCacheKey
+     */
+    private fun coverBitmapFromImageLoader(context: Context, memoryCacheKey: MemoryCache.Key): Bitmap? {
+        return context.imageLoader.memoryCache[memoryCacheKey]
+    }
 
-        directory.mkdirs()
+    /**
+     * Save manga cover Bitmap to temporary share directory.
+     *
+     * @param context for the temporary share directory
+     * @param coverBitmap the cover to save (as Bitmap)
+     * @return cover File in temporary share directory
+     */
+    fun shareCover(context: Context, coverBitmap: Bitmap): File {
+        return saveCover(getTempShareDir(context), coverBitmap)
+    }
+
+    /**
+     * Save manga cover to pictures directory of the device.
+     *
+     * @param context for the pictures directory of the user
+     * @param coverBitmap the cover to save (as Bitmap)
+     * @return cover File in pictures directory
+     */
+    fun saveCover(context: Context, coverBitmap: Bitmap) {
+        saveCover(getPicturesDir(context), coverBitmap)
+    }
 
-        val filename = DiskUtil.buildValidFilename("${manga.title}.${type.extension}")
+    /**
+     * Save a manga cover Bitmap to a new File in a given directory.
+     * Overwrites file if it already exists.
+     *
+     * @param directory The directory in which the new file will be created
+     * @param coverBitmap The manga cover to save
+     * @return the newly created File
+     */
+    private fun saveCover(directory: File, coverBitmap: Bitmap): File {
+        directory.mkdirs()
+        val filename = DiskUtil.buildValidFilename("${manga.title}.${ImageUtil.ImageType.PNG}")
 
         val destFile = File(directory, filename)
-        cover.inputStream().use { input ->
-            destFile.outputStream().use { output ->
-                input.copyTo(output)
-            }
+        destFile.outputStream().use { desFileOutputStream ->
+            coverBitmap.compress(Bitmap.CompressFormat.PNG, 100, desFileOutputStream)
         }
         return destFile
     }

app/src/test/java/eu/kanade/tachiyomi/data/database/CategoryTest.kt

@@ -75,7 +75,7 @@ class CategoryTest {
         assertThat(c.id).isNotZero
 
         // Add a manga to a category
-        val m = db.getMangas().executeAsBlocking()[0]
+        val m = db.getLibraryMangas().executeAsBlocking()[0]
         val mc = MangaCategory.create(m, c)
         db.insertMangaCategory(mc).executeAsBlocking()