Merge "Update existing Folder items' ranks to match their pre-permutation layouts." into ub-launcher3-dorval-polish
diff --git a/src/com/android/launcher3/FolderInfo.java b/src/com/android/launcher3/FolderInfo.java
index 21254ab..7959d40 100644
--- a/src/com/android/launcher3/FolderInfo.java
+++ b/src/com/android/launcher3/FolderInfo.java
@@ -45,6 +45,12 @@
      */
     public static final int FLAG_MULTI_PAGE_ANIMATION = 0x00000004;
 
+    /**
+     * The folder items ranks have been updated such that they appear unchanged with the new
+     * permutation display logic.
+     */
+    public static final int FLAG_ITEM_RANKS_UPDATED = 0x00000008;
+
     public int options;
 
     /**
diff --git a/src/com/android/launcher3/LauncherProvider.java b/src/com/android/launcher3/LauncherProvider.java
index 4813571..a4cd191 100644
--- a/src/com/android/launcher3/LauncherProvider.java
+++ b/src/com/android/launcher3/LauncherProvider.java
@@ -56,6 +56,7 @@
 import com.android.launcher3.compat.UserManagerCompat;
 import com.android.launcher3.config.FeatureFlags;
 import com.android.launcher3.dynamicui.ExtractionUtils;
+import com.android.launcher3.folder.FolderPagedView;
 import com.android.launcher3.graphics.IconShapeOverride;
 import com.android.launcher3.logging.FileLog;
 import com.android.launcher3.model.DbDowngradeHelper;
@@ -725,6 +726,87 @@
                         + "';l.profile=" + serial + ";', ';') where itemType = 0;";
                 db.execSQL(sql);
             }
+
+            updateExistingFoldersToMatchPrePermutationLayout(db);
+        }
+
+        /**
+         * We have changed the way we display items in Folders, but we want existing folders to
+         * appear the same.
+         *
+         * To make this change invisible to existing Folders, we need to update the ranks of the
+         * items such that, when displayed using the permutation, the order remains the same.
+         */
+        private void updateExistingFoldersToMatchPrePermutationLayout(SQLiteDatabase db) {
+            InvariantDeviceProfile idp = new InvariantDeviceProfile(mContext);
+            int maxCols = idp.numFolderColumns;
+            int maxRows = idp.numFolderRows;
+
+            try (SQLiteTransaction t = new SQLiteTransaction(db)) {
+                Cursor c = db.query(Favorites.TABLE_NAME,
+                        new String[] {Favorites._ID, Favorites.OPTIONS},
+                        "itemType=" + Favorites.ITEM_TYPE_FOLDER, null, null, null, null);
+
+                // For every Folder
+                while (c.moveToNext()) {
+                    final long folderId = c.getLong(c.getColumnIndexOrThrow(Favorites._ID));
+                    int options = c.getInt(c.getColumnIndexOrThrow(Favorites.OPTIONS));
+
+                    if ((options & FolderInfo.FLAG_ITEM_RANKS_UPDATED) != 0) {
+                        // The folder has already been updated.
+                        continue;
+                    }
+
+                    // For each item in the Folder
+                    Cursor c2 = db.query(Favorites.TABLE_NAME, new String[] {
+                                    Favorites._ID, Favorites.RANK, Favorites.CELLX, Favorites.CELLY,
+                                    Favorites.OPTIONS},
+                            "container=" + folderId, null, null, null, null);
+
+                    int numItemsInFolder = c2.getCount();
+
+                    // Calculate the grid size.
+                    int[] gridXY = new int[2];
+                    FolderPagedView.calculateGridSize(numItemsInFolder, 0, 0, maxCols, maxRows,
+                            maxCols * maxRows, gridXY);
+                    int gridX = gridXY[0];
+                    int gridY = gridXY[1];
+                    int maxItemsPerPage = gridX * gridY;
+
+                    // We create a mapping from the permutation to the original rank (ie. the
+                    // inverse permutation). This is what we'll use to set the folder items so that
+                    // they appear in their original order.
+                    int[] inversion = new int[numItemsInFolder];
+                    for (int i = 0; i < numItemsInFolder; ++i) {
+                        int permutation = FolderPagedView.getReadingOrderPosForRank(i,
+                                maxItemsPerPage, gridX, null);
+                        inversion[permutation] = i;
+                    }
+
+                    // Now we update the ranks of the folder items. Note that cellX/cellY stay the
+                    // same, due to the permutation.
+                    for (int i = 0; i < numItemsInFolder && c2.moveToNext(); ++i) {
+                        final int rank = c2.getInt(c2.getColumnIndexOrThrow(Favorites.RANK));
+
+                        SQLiteStatement updateItem = db.compileStatement(
+                                "UPDATE favorites SET rank=" + inversion[rank] + " WHERE _id=?");
+                        updateItem.bindLong(1, c2.getInt(c2.getColumnIndexOrThrow(Favorites._ID)));
+                        updateItem.executeUpdateDelete();
+                    }
+                    c2.close();
+
+                    // Mark the folder as having been updated.
+                    options |= FolderInfo.FLAG_ITEM_RANKS_UPDATED;
+                    SQLiteStatement updateFolder = db.compileStatement(
+                            "UPDATE favorites SET options=" + options + " WHERE _id=?");
+                    updateFolder.bindLong(1, folderId);
+                    updateFolder.executeUpdateDelete();
+                }
+                c.close();
+                t.commit();
+            } catch (SQLException ex) {
+                Log.w(TAG, "Error updating folder items to match permutation.", ex);
+            }
         }
 
         @Override
diff --git a/src/com/android/launcher3/folder/FolderPagedView.java b/src/com/android/launcher3/folder/FolderPagedView.java
index 21631fa..bc26fbe 100644
--- a/src/com/android/launcher3/folder/FolderPagedView.java
+++ b/src/com/android/launcher3/folder/FolderPagedView.java
@@ -755,6 +755,10 @@
         return mMaxItemsPerPage;
     }
 
+    public int getReadingOrderPosForRank(int rank) {
+        return getReadingOrderPosForRank(rank, mMaxItemsPerPage, mGridCountX, sTmpArray);
+    }
+
     /**
      * Returns the reading order position for a given rank.
      *
@@ -763,34 +767,44 @@
      *
      *     R0 R1 R4
      *     R2 R3 R5
+     *
+     * @param outXY If notnull, we also return the cell X/Y position.
      */
-    public int getReadingOrderPosForRank(int rank) {
-        if (rank >= mMaxItemsPerPage) {
+    public static int getReadingOrderPosForRank(int rank, int maxItemsPerPage, int gridX,
+            int[] outXY) {
+        outXY = outXY == null ? sTmpArray : outXY;
+        getCellXYPositionForRank(rank, maxItemsPerPage, gridX, outXY);
+
+        if (rank >= maxItemsPerPage) {
             return rank;
         }
 
-        getCellXYPositionForRank(rank, sTmpArray);
-        return sTmpArray[0] + (mGridCountX * sTmpArray[1]);
+        return outXY[0] + (gridX * outXY[1]);
+    }
+
+    public void getCellXYPositionForRank(int rank, int[] outXY) {
+        getCellXYPositionForRank(rank, mMaxItemsPerPage, mGridCountX, outXY);
     }
 
     /**
      * Returns the cell XY position for a Folder item with the given rank.
      */
-    public void getCellXYPositionForRank(int rank, int[] outXY) {
-        boolean onFirstPage = rank < mMaxItemsPerPage;
+    public static void getCellXYPositionForRank(int rank, int maxItemsPerPage, int gridX,
+            int[] outXY) {
+        boolean onFirstPage = rank < maxItemsPerPage;
 
-        if (onFirstPage && mGridCountX == 3) {
+        if (onFirstPage && gridX == 3) {
             outXY[0] = FolderPermutation.THREE_COLS[rank][0];
             outXY[1] = FolderPermutation.THREE_COLS[rank][1];
-        } else if (onFirstPage && mGridCountX == 4) {
+        } else if (onFirstPage && gridX == 4) {
             outXY[0] = FolderPermutation.FOUR_COLS[rank][0];
             outXY[1] = FolderPermutation.FOUR_COLS[rank][1];
-        } else if (onFirstPage && mGridCountX == 5) {
+        } else if (onFirstPage && gridX == 5) {
             outXY[0] = FolderPermutation.FIVE_COLS[rank][0];
             outXY[1] = FolderPermutation.FIVE_COLS[rank][1];
         } else {
-            outXY[0] = (rank % mMaxItemsPerPage) % mGridCountX;
-            outXY[1] = (rank % mMaxItemsPerPage) / mGridCountX;
+            outXY[0] = (rank % maxItemsPerPage) % gridX;
+            outXY[1] = (rank % maxItemsPerPage) / gridX;
         }
     }