refactor autofill classes. basic login support.

src/Android/Autofill/Parser.cs

@@ -0,0 +1,87 @@
+using static Android.App.Assist.AssistStructure;
+using Android.App.Assist;
+
+namespace Bit.Android.Autofill
+{
+    public class Parser
+    {
+        private readonly AssistStructure _structure;
+        private string _uri;
+        private FilledFieldCollection _filledAutofillFieldCollection;
+
+        public Parser(AssistStructure structure)
+        {
+            _structure = structure;
+        }
+
+        public FieldCollection FieldCollection { get; private set; } = new FieldCollection();
+        public string Uri
+        {
+            get => _uri;
+            set
+            {
+                _uri = $"androidapp://{value}";
+            }
+        }
+
+        public void ParseForFill()
+        {
+            Parse(true);
+        }
+
+        public void ParseForSave()
+        {
+            Parse(false);
+        }
+
+        /**
+         * Traverse AssistStructure and add ViewNode metadata to a flat list.
+         */
+        private void Parse(bool forFill)
+        {
+            _filledAutofillFieldCollection = new FilledFieldCollection();
+
+            for(var i = 0; i < _structure.WindowNodeCount; i++)
+            {
+                var node = _structure.GetWindowNodeAt(i);
+                var view = node.RootViewNode;
+                ParseLocked(forFill, view);
+            }
+        }
+
+        private void ParseLocked(bool forFill, ViewNode viewNode)
+        {
+            var autofillHints = viewNode.GetAutofillHints();
+            var autofillType = viewNode.AutofillType;
+            var inputType = viewNode.InputType;
+            var isEditText = viewNode.ClassName == "android.widget.EditText";
+            if(isEditText || (autofillHints?.Length ?? 0) > 0)
+            {
+                if(forFill)
+                {
+                    var f = new Field(viewNode);
+                    FieldCollection.Add(f);
+
+                    if(Uri == null)
+                    {
+                        Uri = viewNode.IdPackage;
+                    }
+                }
+                else
+                {
+                    _filledAutofillFieldCollection.Add(new FilledField(viewNode));
+                }
+            }
+
+            for(var i = 0; i < viewNode.ChildCount; i++)
+            {
+                ParseLocked(forFill, viewNode.GetChildAt(i));
+            }
+        }
+
+        public FilledFieldCollection GetClientFormData()
+        {
+            return _filledAutofillFieldCollection;
+        }
+    }
+}