Enable backend media handling; add media check

AnkiDroid/src/main/java/com/ichi2/anki/servicelayer/scopedstorage/MigrateEssentialFiles.kt

@@ -487,7 +487,12 @@ internal constructor(
          */
         val PRIORITY_FILES = listOf(
             SQLiteDBFiles("collection.anki2"), // Anki collection
-            SQLiteDBFiles("collection.media.ad.db2"), // media database + journal
+            if (BackendFactory.defaultLegacySchema) {
+                SQLiteDBFiles("collection.media.ad.db2")
+            } else {
+                // this is created on demand in the new backend
+                OptionalFile("collection.media.db")
+            }, // media database + journal
             OptionalFile(".nomedia"), // written immediately
             OptionalFile("collection.log") // written immediately and conflicts
         )

AnkiDroid/src/main/java/com/ichi2/async/CollectionTask.kt

@@ -40,6 +40,7 @@ import com.ichi2.libanki.sched.DeckTreeNode
 import com.ichi2.libanki.sched.TreeNode
 import com.ichi2.utils.*
 import com.ichi2.utils.SyncStatus.Companion.ignoreDatabaseModification
+import net.ankiweb.rsdroid.BackendFactory
 import net.ankiweb.rsdroid.RustCleanup
 import org.apache.commons.compress.archivers.zip.ZipFile
 import timber.log.Timber
@@ -1078,8 +1079,13 @@ open class CollectionTask<Progress, Result>(val task: TaskDelegateBase<Progress,
     class DeleteMedia(private val unused: List<String>) : TaskDelegate<Void, Int>() {
         override fun task(col: Collection, collectionTask: ProgressSenderAndCancelListener<Void>): Int {
             val m = col.media
-            for (fname in unused) {
-                m.removeFile(fname)
+            if (!BackendFactory.defaultLegacySchema) {
+                // FIXME: this provides progress info that is not currently used
+                col.newMedia.removeFiles(unused)
+            } else {
+                for (fname in unused) {
+                    m.removeFile(fname)
+                }
             }
             return unused.size
         }

AnkiDroid/src/main/java/com/ichi2/libanki/BackendMedia.kt

@@ -0,0 +1,71 @@
+/***************************************************************************************
+ * Copyright (c) 2012 Ankitects Pty Ltd <http://apps.ankiweb.net>                       *
+ *                                                                                      *
+ * This program is free software; you can redistribute it and/or modify it under        *
+ * the terms of the GNU General Public License as published by the Free Software        *
+ * Foundation; either version 3 of the License, or (at your option) any later           *
+ * version.                                                                             *
+ *                                                                                      *
+ * This program is distributed in the hope that it will be useful, but WITHOUT ANY      *
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A      *
+ * PARTICULAR PURPOSE. See the GNU General Public License for more details.             *
+ *                                                                                      *
+ * You should have received a copy of the GNU General Public License along with         *
+ * this program.  If not, see <http://www.gnu.org/licenses/>.                           *
+ ****************************************************************************************/
+
+package com.ichi2.libanki
+
+class BackendMedia(val col: CollectionV16, server: Boolean) : Media(col, server) {
+    override fun connect() {
+        // no-op
+    }
+
+    override fun close() {
+        // no-op
+    }
+
+    override fun rebuildIfInvalid() {
+        // no-op
+    }
+
+    override fun findChanges(force: Boolean) {
+        // no-op
+    }
+
+    override fun markFileAdd(fname: String) {
+        // no-op; will no longer be called when migrating to new import code.
+    }
+
+    override fun forceResync() {
+        col.backend.removeMediaDb(col.path)
+    }
+
+    override fun removeFile(fname: String) {
+        removeFiles(listOf(fname))
+    }
+
+    // markFileAdd
+
+    // FIXME: this also provides trash count, but UI can not handle it yet
+    override fun check(): List<List<String>> {
+        val out = col.backend.checkMedia()
+        return listOf(out.missingList, out.unusedList, listOf())
+    }
+
+    // FIXME: this currently removes files immediately, as the UI does not expose a way
+    // to empty the trash or restore media files yet
+    fun removeFiles(files: Iterable<String>) {
+        col.backend.trashMediaFiles(files)
+        emptyTrash()
+    }
+
+    private fun emptyTrash() {
+        col.backend.emptyTrash()
+    }
+
+    @Suppress("UNUSED")
+    private fun restoreTrash() {
+        col.backend.restoreTrash()
+    }
+}

AnkiDroid/src/main/java/com/ichi2/libanki/Collection.kt

@@ -100,6 +100,8 @@ open class Collection constructor(
 
     open val newBackend: CollectionV16
         get() = throw Exception("invalid call to newBackend on old backend")
+    open val newMedia: BackendMedia
+        get() = throw Exception("invalid call to newMedia on old backend")
 
     @VisibleForTesting(otherwise = VisibleForTesting.NONE)
     fun debugEnsureNoOpenPointers() {
@@ -144,8 +146,8 @@ open class Collection constructor(
     private var mStartReps: Int
 
     // BEGIN: SQL table columns
-    var crt: Long = 0
-    var mod: Long = 0
+    open var crt: Long = 0
+    open var mod: Long = 0
     var scm: Long = 0
     var dirty: Boolean = false
     private var mUsn = 0
@@ -163,7 +165,7 @@ open class Collection constructor(
     private var mLogHnd: PrintWriter? = null
 
     init {
-        media = Media(this, server)
+        media = initMedia()
         val created = reopen()
         log(path, VersionUtils.pkgVersionName)
         // mLastSave = getTime().now(); // assigned but never accessed - only leaving in for upstream comparison
@@ -186,6 +188,10 @@ open class Collection constructor(
         }
     }
 
+    protected open fun initMedia(): Media {
+        return Media(this, server)
+    }
+
     @KotlinCleanup("remove :DeckManager, remove ? on return value")
     protected open fun initDecks(deckConf: String?): DeckManager? {
         val deckManager: DeckManager = Decks(this)

AnkiDroid/src/main/java/com/ichi2/libanki/CollectionV16.kt

@@ -48,9 +48,26 @@ class CollectionV16(
         return ConfigV16(RustConfigBackend(backend))
     }
 
+    override fun initMedia(): BackendMedia {
+        return BackendMedia(this, server)
+    }
+
     override val newBackend: CollectionV16
         get() = this
 
+    override val newMedia: BackendMedia
+        get() = this.media as BackendMedia
+
+    override fun flush(mod: Long) {
+        // no-op
+    }
+
+    override var mod: Long = 0
+        get() = db.queryLongScalar("select mod from col")
+
+    override var crt: Long = 0
+        get() = db.queryLongScalar("select crt from col")
+
     /** col.conf is now unused, handled by [ConfigV16] which has a separate table */
     override fun flushConf(): Boolean = false
 

AnkiDroid/src/main/java/com/ichi2/libanki/Media.java

@@ -141,8 +141,6 @@ public Media(Collection col, boolean server) {
                 Timber.e("Cannot create media directory: %s", mDir);
             }
         }
-        // change database
-//        connect();
     }
 
 
@@ -182,7 +180,7 @@ public void _initDB() {
     }
 
 
-    public void maybeUpgrade() {
+    private void maybeUpgrade() {
         String oldPath = dir() + ".db";
         File oldDbFile = new File(oldPath);
         if (oldDbFile.exists()) {

AnkiDroid/src/test/java/com/ichi2/anki/servicelayer/scopedstorage/MigrateEssentialFilesTest.kt

@@ -215,15 +215,15 @@ class MigrateEssentialFilesTest : RobolectricTest() {
 
         col.close() // required for Windows, can't delete if locked.
 
-        CompatHelper.compat.deleteFile(File(defaultCollectionSourcePath, "collection.media.ad.db2"))
+        CompatHelper.compat.deleteFile(File(defaultCollectionSourcePath, "collection.anki2"))
 
         val ex = assertThrows<MissingEssentialFileException> {
             executeAlgorithmSuccessfully(defaultCollectionSourcePath) {
                 Mockito.doReturn(Mockito.mock(LockedCollection::class.java)).whenever(it).createLockedCollection()
             }
         }
 
-        assertThat(ex.file.name, equalTo("collection.media.ad.db2"))
+        assertThat(ex.file.name, equalTo("collection.anki2"))
     }
 
     /**

AnkiDroid/src/test/java/com/ichi2/libanki/CheckMediaTest.kt

@@ -21,6 +21,7 @@ import com.ichi2.anki.RunInBackground
 import com.ichi2.async.CollectionTask
 import com.ichi2.async.CollectionTask.CheckMedia
 import com.ichi2.async.TaskManager
+import net.ankiweb.rsdroid.BackendFactory
 import org.hamcrest.CoreMatchers.equalTo
 import org.hamcrest.MatcherAssert.assertThat
 import org.junit.Test
@@ -38,6 +39,10 @@ class CheckMediaTest : RobolectricTest() {
     @Suppress("deprecation")
     @Throws(ExecutionException::class, InterruptedException::class)
     fun checkMediaWorksAfterMissingMetaTable() {
+        if (!BackendFactory.defaultLegacySchema) {
+            // this should not happen on the backend, as it creates the tables in a transaction
+            return
+        }
         // 7421
         col.media.db.database.execSQL("drop table meta")
         assertThat(