feat: Make all file access permission optional on full builds

AnkiDroid/src/main/java/com/ichi2/anki/InitialActivity.kt

@@ -260,6 +260,10 @@ fun selectStoragePermissions(context: Context): PermissionSet {
     val canAccessLegacyStorage = Build.VERSION.SDK_INT < Build.VERSION_CODES.Q || Environment.isExternalStorageLegacy()
     val currentFolderIsAccessibleAndLegacy = canAccessLegacyStorage && isLegacyStorage(context, setCollectionPath = false) == true
 
+    if (CollectionHelper.isAppPrivateStorage(context) && !InitialActivity.wasFreshInstall(context.sharedPrefs())) {
+        return PermissionSet.APP_PRIVATE
+    }
+
     return selectStoragePermissions(
         canManageExternalStorage = Permissions.canManageExternalStorage(context),
         currentFolderIsAccessibleAndLegacy = currentFolderIsAccessibleAndLegacy,

AnkiDroid/src/main/java/com/ichi2/anki/ui/windows/permissions/PermissionsActivity.kt

@@ -22,14 +22,13 @@ import android.os.Parcelable
 import androidx.activity.addCallback
 import androidx.core.content.IntentCompat
 import androidx.fragment.app.commit
+import com.google.android.material.dialog.MaterialAlertDialogBuilder
 import com.ichi2.anki.AnkiActivity
 import com.ichi2.anki.PermissionSet
 import com.ichi2.anki.R
+import com.ichi2.anki.common.storage.CollectionHelper
 import com.ichi2.anki.common.utils.android.showThemedToast
 import com.ichi2.anki.databinding.ActivityPermissionsBinding
-import com.ichi2.anki.ui.windows.permissions.PermissionsFragment.Companion.HAS_ALL_PERMISSIONS_KEY
-import com.ichi2.anki.ui.windows.permissions.PermissionsFragment.Companion.PERMISSIONS_FRAGMENT_RESULT_KEY
-import com.ichi2.anki.utils.ext.setFragmentResultListener
 import com.ichi2.themes.Themes
 import com.ichi2.themes.setTransparentStatusBar
 import dev.androidbroadcast.vbpd.viewBinding
@@ -60,8 +59,6 @@ class PermissionsActivity : AnkiActivity(R.layout.activity_permissions) {
         Themes.setTheme(this)
         setTransparentStatusBar()
 
-        binding.continueButton.setOnClickListener { finish() }
-
         // #20881: Activity should not be launchd without extras
         val permissionSet = IntentCompat.getParcelableExtra(intent, EXTRA_PERMISSIONS_SET, PermissionSet::class.java)
         if (permissionSet == null) {
@@ -75,20 +72,36 @@ class PermissionsActivity : AnkiActivity(R.layout.activity_permissions) {
             requireNotNull(permissionSet.permissionsFragment?.getDeclaredConstructor()?.newInstance()) {
                 "invalid permissionsFragment"
             }
-        setFragmentResultListener(PERMISSIONS_FRAGMENT_RESULT_KEY) { _, bundle ->
-            val hasAllPermissions = bundle.getBoolean(HAS_ALL_PERMISSIONS_KEY)
-            setContinueButtonEnabled(hasAllPermissions)
-        }
 
         supportFragmentManager.commit {
             replace(R.id.fragment_container, permissionsFragment)
         }
+
+        binding.continueButton.setOnClickListener {
+            if (permissionSet.hasRequiredPermissions(this)) {
+                finish()
+                return@setOnClickListener
+            }
+
+            showPrivateStorageWarningDialog()
+        }
         // only close the activity by tapping the continue button
         onBackPressedDispatcher.addCallback {}
     }
 
-    fun setContinueButtonEnabled(isEnabled: Boolean) {
-        binding.continueButton.isEnabled = isEnabled
+    // TODO Rethink the UI - selection UI is preferred over a warning dialog: #21049
+    private fun showPrivateStorageWarningDialog() {
+        MaterialAlertDialogBuilder(this)
+            .setTitle(R.string.private_storage_warning_title)
+            .setMessage(R.string.private_storage_warning)
+            .setPositiveButton(R.string.dialog_continue) { _, _ ->
+                if (!CollectionHelper.setPrivateStoragePath(this)) {
+                    showThemedToast(this, R.string.something_wrong, false)
+                    return@setPositiveButton
+                }
+                finish()
+            }.setNegativeButton(R.string.dialog_cancel, null)
+            .show()
     }
 
     companion object {

AnkiDroid/src/main/res/layout/activity_permissions.xml

@@ -45,7 +45,7 @@
             android:layout_height="wrap_content"
             android:layout_margin="16dp"
             android:paddingVertical="12dp"
-            android:text="@string/dialog_continue"
+            android:text="@string/dialog_skip"
             app:layout_constraintBottom_toBottomOf="parent"
             />
 

AnkiDroid/src/main/res/values/01-core.xml

@@ -157,7 +157,7 @@
     <string name="new_unsafe_collection">The new collection will be deleted from your phone if you uninstall AnkiDroid</string>
 
     <!-- Permissions screen -->
-    <string name="permissions_screen_headline">AnkiDroid needs some permissions to work</string>
+    <string name="permissions_screen_headline">AnkiDroid works better with these permissions</string>
     <string name="permissions_screen_optional_headline" comment="Explains that there are optional permissions that can be granted to AnkiDroid.">AnkiDroid works best with these permissions</string>
     <string name="storage_access_title">Storage access</string>
     <string name="storage_access_summary">Saves your collection in a safe place that will not be deleted if the app is uninstalled</string>

AnkiDroid/src/main/res/values/03-dialogs.xml

@@ -60,6 +60,7 @@
     <string name="dialog_remove">Remove</string>
     <string name="dialog_exit" comment="Label for a button which will exit/finish the current screen">Exit</string>
     <string name="dialog_continue">Continue</string>
+    <string name="dialog_skip">Skip</string>
     <string name="dialog_processing">Processing…</string>
     <string name="dialog_positive_create" comment="Create a new collection, probably erasing the previous one, may be necessary in case of error.">Create</string>
     <string name="dialog_positive_delete" maxLength="28">Delete</string>
@@ -208,6 +209,9 @@
     <string name="dismiss_backup_warning_new_user">Due to Android privacy changes, your data and automated backups will be deleted from your phone if the app is uninstalled</string>
     <string name="dismiss_backup_warning_upgrade">Due to Android privacy changes, your data and automated backups will be inaccessible if the app is uninstalled</string>
 
+    <string name="private_storage_warning_title">Limited storage access</string>
+    <string name="private_storage_warning">Without this permission, your AnkiDroid collection will be stored in app private storage and will be permanently deleted if you uninstall AnkiDroid.</string>
+
     <string name="create_deck_numeric_hint">If you have deck ordering issues (e.g. ‘10’ appears before ‘2’), replace ‘2’ with ‘02’</string>
 
     <!-- Set Due Date -->

AnkiDroid/src/test/java/com/ichi2/anki/ui/windows/permissions/PermissionsActivityTest.kt

@@ -16,27 +16,42 @@
 package com.ichi2.anki.ui.windows.permissions
 
 import android.content.Context
+import android.content.DialogInterface
 import android.content.Intent
 import androidx.appcompat.widget.AppCompatButton
+import androidx.core.content.edit
 import androidx.fragment.app.commitNow
 import androidx.test.core.app.ActivityScenario
 import androidx.test.core.app.ActivityScenario.ActivityAction
 import androidx.test.core.app.ApplicationProvider
 import androidx.test.ext.junit.runners.AndroidJUnit4
+import com.ichi2.anki.AnkiDroidApp
 import com.ichi2.anki.PermissionSet
 import com.ichi2.anki.R
 import com.ichi2.anki.RobolectricTest
+import com.ichi2.anki.common.storage.CollectionHelper
 import com.ichi2.testutils.HamcrestUtils.containsInAnyOrder
+import com.ichi2.testutils.grantPermissions
 import org.hamcrest.MatcherAssert.assertThat
 import org.hamcrest.Matchers.equalTo
+import org.junit.Before
 import org.junit.Test
 import org.junit.runner.RunWith
+import org.robolectric.shadows.ShadowDialog
 import org.robolectric.shadows.ShadowToast
+import java.io.File
 import kotlin.test.assertEquals
 import kotlin.test.assertFailsWith
 
 @RunWith(AndroidJUnit4::class)
 class PermissionsActivityTest : RobolectricTest() {
+    @Before
+    fun clearStorage() {
+        AnkiDroidApp.sharedPrefs().edit {
+            remove(CollectionHelper.PREF_COLLECTION_PATH)
+        }
+    }
+
     @Test
     fun testActivityCantBeClosedByBackButton() {
         testActivity { activity ->
@@ -47,22 +62,59 @@ class PermissionsActivityTest : RobolectricTest() {
 
     @Test
     fun testOnClickingContinueActivityFinishes() {
+        grantPermissions(*ARBITRARY_PERMISSION_SET.permissions.toTypedArray())
         testActivity { activity ->
-            activity.setContinueButtonEnabled(true)
             activity.findViewById<AppCompatButton>(R.id.continue_button).performClick()
             assertThat("activity is finishing", activity.isFinishing)
         }
     }
 
     @Test
-    fun `error toast is shown if EXTRA_PERMISSIONS_SET is missing`() {
+    fun testOnClickingContinueShowsDialogWhenStorageNotGranted() {
+        testActivity { activity ->
+            activity.findViewById<AppCompatButton>(R.id.continue_button).performClick()
+            advanceRobolectricLooper()
+            val dialog = ShadowDialog.getLatestDialog()
+            assertThat("dialog is shown", dialog?.isShowing == true)
+        }
+    }
+
+    @Test
+    fun testCancelingDialogDoesNotFinish() {
+        testActivity { activity ->
+            activity.findViewById<AppCompatButton>(R.id.continue_button).performClick()
+            advanceRobolectricLooper()
+            clickAlertDialogButton(DialogInterface.BUTTON_NEGATIVE, false)
+            advanceRobolectricLooper()
+            assertThat("activity is not finishing", !activity.isFinishing)
+        }
+    }
+
+    @Test
+    fun `error toast is shown if PERMISSIONS_SET_EXTRA is missing`() {
         testInvalidActivityFinishes()
         assertThat(
             ShadowToast.getTextOfLatestToast(),
             equalTo(getResourceString(R.string.something_wrong)),
         )
     }
 
+    @Test
+    fun testConfirmingDialogWritesCorrectPath() {
+        testActivity { activity ->
+            activity.findViewById<AppCompatButton>(R.id.continue_button).performClick()
+            advanceRobolectricLooper()
+            clickAlertDialogButton(DialogInterface.BUTTON_POSITIVE, false)
+            advanceRobolectricLooper()
+            val expectedPath = File(CollectionHelper.getAppSpecificExternalDirectories(activity).first(), "AnkiDroid").absolutePath
+            val actualPath =
+                AnkiDroidApp
+                    .sharedPrefs()
+                    .getString(CollectionHelper.PREF_COLLECTION_PATH, null)
+            assertThat("collection path is set to private dir", actualPath, equalTo(expectedPath))
+        }
+    }
+
     @Test
     fun `Each screen starts normally and has the same permissions of a PermissionSet`() {
         testActivity { activity ->

anki-common/src/main/kotlin/com/ichi2/anki/common/storage/CollectionHelper.kt

@@ -6,6 +6,7 @@ package com.ichi2.anki.common.storage
 import android.content.Context
 import android.content.SharedPreferences
 import androidx.annotation.VisibleForTesting
+import androidx.core.content.edit
 import com.ichi2.anki.common.preferences.sharedPrefs
 import com.ichi2.anki.common.utils.android.isInstrumentationTest
 import com.ichi2.anki.exception.StorageAccessException
@@ -102,6 +103,30 @@ object CollectionHelper {
      */
     fun getAppSpecificExternalDirectories(context: Context): List<File> = context.getExternalFilesDirs(null)?.filterNotNull() ?: listOf()
 
+    /**
+     * Checks if the currently configured collection path is an app-specific directory.
+     */
+    fun isAppPrivateStorage(context: Context): Boolean {
+        val currentPath = context.sharedPrefs().getString(PREF_COLLECTION_PATH, null) ?: return false
+        return getAppSpecificExternalDirectories(context).any { currentPath.startsWith(it.absolutePath) }
+    }
+
+    /**
+     * Sets the collection path to the app-specific private directory.
+     * @return true if successful, false otherwise.
+     */
+    fun setPrivateStoragePath(context: Context): Boolean {
+        val externalFilesDirs = getAppSpecificExternalDirectories(context)
+        if (externalFilesDirs.isEmpty()) {
+            return false
+        }
+        val privateDir = File(externalFilesDirs.first(), "AnkiDroid")
+        context.sharedPrefs().edit {
+            putString(PREF_COLLECTION_PATH, privateDir.absolutePath)
+        }
+        return true
+    }
+
     /**
      * Returns the absolute path to the private AnkiDroid directory under the app-specific, internal storage directory.
      *