Cache custom covers (close #1492)

app/src/main/kotlin/org/koitharu/kotatsu/settings/override/OverrideConfigViewModel.kt

@@ -1,23 +1,39 @@
 package org.koitharu.kotatsu.settings.override
 
+import android.content.Context
+import androidx.core.net.toUri
 import androidx.lifecycle.SavedStateHandle
 import dagger.hilt.android.lifecycle.HiltViewModel
+import dagger.hilt.android.qualifiers.ApplicationContext
 import kotlinx.coroutines.Dispatchers
 import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.withContext
+import okio.buffer
+import okio.sink
 import org.koitharu.kotatsu.core.model.parcelable.ParcelableManga
 import org.koitharu.kotatsu.core.nav.AppRouter
 import org.koitharu.kotatsu.core.parser.MangaDataRepository
 import org.koitharu.kotatsu.core.ui.BaseViewModel
 import org.koitharu.kotatsu.core.ui.model.MangaOverride
+import org.koitharu.kotatsu.core.util.MimeTypes
 import org.koitharu.kotatsu.core.util.ext.MutableEventFlow
 import org.koitharu.kotatsu.core.util.ext.call
+import org.koitharu.kotatsu.core.util.ext.isFileUri
+import org.koitharu.kotatsu.core.util.ext.openSource
 import org.koitharu.kotatsu.core.util.ext.require
+import org.koitharu.kotatsu.core.util.ext.toMimeTypeOrNull
+import org.koitharu.kotatsu.core.util.ext.toUriOrNull
 import org.koitharu.kotatsu.parsers.model.Manga
+import org.koitharu.kotatsu.parsers.util.md5
+import java.io.File
 import javax.inject.Inject
 
+private const val DIR_COVERS = "covers"
+
 @HiltViewModel
 class OverrideConfigViewModel @Inject constructor(
 	savedStateHandle: SavedStateHandle,
+	@ApplicationContext private val context: Context,
 	private val dataRepository: MangaDataRepository,
 ) : BaseViewModel() {
 
@@ -34,9 +50,12 @@ class OverrideConfigViewModel @Inject constructor(
 
 	fun save(title: String?) {
 		launchLoadingJob(Dispatchers.Default) {
-			val override = checkNotNull(data.value).second.copy(
-				title = title,
-			)
+			val override = checkNotNull(data.value).second.let {
+				it.copy(
+					title = title,
+					coverUrl = it.coverUrl?.cachedFile(),
+				)
+			}
 			dataRepository.setOverride(manga, override)
 			onSaved.call(Unit)
 		}
@@ -49,5 +68,33 @@ class OverrideConfigViewModel @Inject constructor(
 		)
 	}
 
+	private suspend fun String.cachedFile(): String {
+		val uri = toUriOrNull()
+		if (uri == null || uri.isFileUri()) {
+			return this
+		}
+		val cacheDir = context.getExternalFilesDir(DIR_COVERS) ?: return this
+		val cr = context.contentResolver
+		val ext = cr.getType(uri)?.toMimeTypeOrNull()?.let {
+			MimeTypes.getExtension(it)
+		}
+		val fileName = buildString {
+			append(this@cachedFile.md5())
+			if (!ext.isNullOrEmpty()) {
+				append('.')
+				append(ext)
+			}
+		}
+		return withContext(Dispatchers.IO) {
+			val dest = File(cacheDir, fileName)
+			cr.openSource(uri).use { source ->
+				dest.sink().buffer().use { sink ->
+					sink.writeAll(source)
+				}
+			}
+			dest
+		}.toUri().toString()
+	}
+
 	private fun emptyOverride() = MangaOverride(null, null, null)
 }