First draft at a subtasks metadata migration

astrid/plugin-src/com/todoroo/astrid/subtasks/AstridOrderedListUpdater.java

@@ -322,7 +322,7 @@ public abstract class AstridOrderedListUpdater<LIST> {
         return tree.toString();
     }
 
-    private void recursivelySerializeChildren(Node node, JSONArray serializeTo) throws JSONException {
+    public static void recursivelySerializeChildren(Node node, JSONArray serializeTo) throws JSONException {
         ArrayList<Node> children = node.children;
         for (Node child : children) {
             JSONObject childObj = new JSONObject();

astrid/plugin-src/com/todoroo/astrid/subtasks/SubtasksMetadataMigration.java

@@ -0,0 +1,118 @@
+package com.todoroo.astrid.subtasks;
+
+import java.util.ArrayList;
+
+import org.json.JSONArray;
+import org.json.JSONException;
+
+import android.util.Log;
+
+import com.todoroo.andlib.data.TodorooCursor;
+import com.todoroo.andlib.service.Autowired;
+import com.todoroo.andlib.service.DependencyInjectionService;
+import com.todoroo.andlib.sql.Order;
+import com.todoroo.andlib.sql.Query;
+import com.todoroo.andlib.utility.Preferences;
+import com.todoroo.astrid.dao.MetadataDao.MetadataCriteria;
+import com.todoroo.astrid.data.Metadata;
+import com.todoroo.astrid.data.TagData;
+import com.todoroo.astrid.service.MetadataService;
+import com.todoroo.astrid.service.TagDataService;
+import com.todoroo.astrid.subtasks.AstridOrderedListUpdater.Node;
+
+@SuppressWarnings("deprecation") // Subtasks metadata is deprecated
+public class SubtasksMetadataMigration {
+
+    @Autowired
+    private TagDataService tagDataService;
+
+    @Autowired
+    private MetadataService metadataService;
+
+    public SubtasksMetadataMigration() {
+        DependencyInjectionService.getInstance().inject(this);
+    }
+
+    public void performMigration() {
+        TodorooCursor<Metadata> subtasksMetadata = metadataService.query(Query.select(Metadata.PROPERTIES)
+                .where(MetadataCriteria.withKey(SubtasksMetadata.METADATA_KEY))
+                .orderBy(Order.asc(SubtasksMetadata.TAG), Order.asc(SubtasksMetadata.ORDER)));
+        try {
+            Metadata m = new Metadata();
+            for (subtasksMetadata.moveToFirst(); !subtasksMetadata.isAfterLast(); subtasksMetadata.moveToNext()) {
+                m.readFromCursor(subtasksMetadata);
+                String tag = m.getValue(SubtasksMetadata.TAG);
+                processTag(tag, subtasksMetadata);
+            }
+        } finally {
+            subtasksMetadata.close();
+        }
+    }
+
+    @SuppressWarnings("nls")
+    private void processTag(String tag, TodorooCursor<Metadata> subtasksMetadata) {
+        Metadata item = new Metadata();
+        TagData td = null;
+        try {
+            if (!SubtasksMetadata.LIST_ACTIVE_TASKS.equals(tag)) {
+                String idString = tag.replace("td:", "");
+                long id = Long.parseLong(idString);
+                td = tagDataService.fetchById(id, TagData.ID);
+            }
+        } catch (NumberFormatException e) {
+            Log.e("subtasks-migration", "Could not parse tag id from " + tag, e);
+        }
+
+        if (td == null && !SubtasksMetadata.LIST_ACTIVE_TASKS.equals(tag)) {
+            for (; !subtasksMetadata.isAfterLast(); subtasksMetadata.moveToNext()) {
+                item.readFromCursor(subtasksMetadata);
+                if (!item.getValue(SubtasksMetadata.TAG).equals(tag))
+                    break;
+            }
+        } else {
+            String newTree = buildTreeModelFromMetadata(tag, subtasksMetadata);
+            if (td != null) {
+                td.setValue(TagData.TAG_ORDERING, newTree);
+                tagDataService.save(td);
+            } else {
+                Preferences.setString(SubtasksUpdater.ACTIVE_TASKS_ORDER, newTree);
+            }
+        }
+
+        subtasksMetadata.moveToPrevious(); // Move back one to undo the last iteration of the for loop
+    }
+
+    private String buildTreeModelFromMetadata(String tag, TodorooCursor<Metadata> cursor) {
+        Metadata item = new Metadata();
+        Node root = new Node(-1, null, -1);
+        for (; !cursor.isAfterLast(); cursor.moveToNext()) {
+            item.readFromCursor(cursor);
+            if (!item.getValue(SubtasksMetadata.TAG).equals(tag))
+                break;
+
+            int indent = item.getValue(SubtasksMetadata.INDENT);
+            Node parent = findNextParentForIndent(root, indent);
+            Node newNode = new Node(item.getValue(Metadata.TASK), parent, parent.indent + 1);
+            parent.children.add(newNode);
+        }
+
+        try {
+            JSONArray array = new JSONArray();
+            AstridOrderedListUpdater.recursivelySerializeChildren(root, new JSONArray());
+            return array.toString();
+        } catch (JSONException e) {
+            return "[]"; //$NON-NLS-1$
+        }
+    }
+
+    private Node findNextParentForIndent(Node root, int indent) {
+        if (indent <= 0)
+            return root;
+
+        ArrayList<Node> children = root.children;
+        if (children.size() == 0)
+            return root;
+
+        return findNextParentForIndent(children.get(children.size() - 1), indent - 1);
+    }
+}