feat: add keyboard service interceptor to prevent default ops executi…

…on (#902)

* feat: add keyboard service interceptor to prevent default ops execution

* chore: add logs

lib/src/editor/editor_component/service/keyboard_service.dart

@@ -1,5 +1,6 @@
 import 'package:appflowy_editor/appflowy_editor.dart';
 import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
 
 /// [AppFlowyKeyboardService] is responsible for processing shortcut keys,
 ///   like command, shift, control keys.
@@ -41,4 +42,67 @@ abstract class AppFlowyKeyboardService {
   ///
   /// Used in mobile
   void enableKeyBoard(Selection selection);
+
+  /// Register interceptor
+  void registerInterceptor(AppFlowyKeyboardServiceInterceptor interceptor);
+
+  /// Unregister interceptor
+  void unregisterInterceptor(AppFlowyKeyboardServiceInterceptor interceptor);
+}
+
+/// [AppFlowyKeyboardServiceInterceptor] is used to intercept the keyboard service.
+///
+/// If the interceptor returns `true`, the keyboard service will not perform
+/// the built-in operation.
+abstract class AppFlowyKeyboardServiceInterceptor {
+  /// Intercept insert operation
+  Future<bool> interceptInsert(
+    TextEditingDeltaInsertion insertion,
+    EditorState editorState,
+    List<CharacterShortcutEvent> characterShortcutEvents,
+  ) async {
+    return false;
+  }
+
+  /// Intercept delete operation
+  Future<bool> interceptDelete(
+    TextEditingDeltaDeletion deletion,
+    EditorState editorState,
+  ) async {
+    return false;
+  }
+
+  /// Intercept replace operation
+  Future<bool> interceptReplace(
+    TextEditingDeltaReplacement replacement,
+    EditorState editorState,
+    List<CharacterShortcutEvent> characterShortcutEvents,
+  ) async {
+    return false;
+  }
+
+  /// Intercept non-text update operation
+  Future<bool> interceptNonTextUpdate(
+    TextEditingDeltaNonTextUpdate nonTextUpdate,
+    EditorState editorState,
+    List<CharacterShortcutEvent> characterShortcutEvents,
+  ) async {
+    return false;
+  }
+
+  /// Intercept perform action operation
+  Future<bool> interceptPerformAction(
+    TextInputAction action,
+    EditorState editorState,
+  ) async {
+    return false;
+  }
+
+  /// Intercept floating cursor operation
+  Future<bool> interceptFloatingCursor(
+    RawFloatingCursorPoint point,
+    EditorState editorState,
+  ) async {
+    return false;
+  }
 }

lib/src/editor/editor_component/service/keyboard_service_widget.dart

@@ -36,6 +36,8 @@ class KeyboardServiceWidgetState extends State<KeyboardServiceWidget>
   late final TextInputService textInputService;
   late final FocusNode focusNode;
 
+  final List<AppFlowyKeyboardServiceInterceptor> interceptors = [];
+
   // previous selection
   Selection? previousSelection;
 
@@ -61,36 +63,7 @@ class KeyboardServiceWidgetState extends State<KeyboardServiceWidget>
     editorState.service.selectionService
         .registerGestureInterceptor(interceptor);
 
-    textInputService = NonDeltaTextInputService(
-      onInsert: (insertion) async => await onInsert(
-        insertion,
-        editorState,
-        widget.characterShortcutEvents,
-      ),
-      onDelete: (deletion) async => await onDelete(
-        deletion,
-        editorState,
-      ),
-      onReplace: (replacement) async => await onReplace(
-        replacement,
-        editorState,
-        widget.characterShortcutEvents,
-      ),
-      onNonTextUpdate: (nonTextUpdate) async => await onNonTextUpdate(
-        nonTextUpdate,
-        editorState,
-        widget.characterShortcutEvents,
-      ),
-      onPerformAction: (action) async => await onPerformAction(
-        action,
-        editorState,
-      ),
-      onFloatingCursor: (point) => onFloatingCursorUpdate(
-        point,
-        editorState,
-      ),
-      contentInsertionConfiguration: widget.contentInsertionConfiguration,
-    );
+    textInputService = buildTextInputService();
 
     focusNode = widget.focusNode ?? FocusNode(debugLabel: 'keyboard service');
     focusNode.addListener(_onFocusChanged);
@@ -162,6 +135,16 @@ class KeyboardServiceWidgetState extends State<KeyboardServiceWidget>
     return child;
   }
 
+  @override
+  void registerInterceptor(AppFlowyKeyboardServiceInterceptor interceptor) {
+    interceptors.add(interceptor);
+  }
+
+  @override
+  void unregisterInterceptor(AppFlowyKeyboardServiceInterceptor interceptor) {
+    interceptors.remove(interceptor);
+  }
+
   /// handle hardware keyboard
   KeyEventResult _onKeyEvent(FocusNode node, KeyEvent event) {
     if ((event is! KeyDownEvent && event is! KeyRepeatEvent) ||
@@ -344,4 +327,130 @@ class KeyboardServiceWidgetState extends State<KeyboardServiceWidget>
       }
     }
   }
+
+  NonDeltaTextInputService buildTextInputService() {
+    return NonDeltaTextInputService(
+      onInsert: (insertion) async {
+        for (final interceptor in interceptors) {
+          final result = await interceptor.interceptInsert(
+            insertion,
+            editorState,
+            widget.characterShortcutEvents,
+          );
+          if (result) {
+            AppFlowyEditorLog.input.info(
+              'keyboard service onInsert - intercepted by interceptor: $interceptor',
+            );
+            return;
+          }
+        }
+
+        await onInsert(
+          insertion,
+          editorState,
+          widget.characterShortcutEvents,
+        );
+      },
+      onDelete: (deletion) async {
+        for (final interceptor in interceptors) {
+          final result = await interceptor.interceptDelete(
+            deletion,
+            editorState,
+          );
+          if (result) {
+            AppFlowyEditorLog.input.info(
+              'keyboard service onDelete - intercepted by interceptor: $interceptor',
+            );
+            return;
+          }
+        }
+
+        await onDelete(
+          deletion,
+          editorState,
+        );
+      },
+      onReplace: (replacement) async {
+        for (final interceptor in interceptors) {
+          final result = await interceptor.interceptReplace(
+            replacement,
+            editorState,
+            widget.characterShortcutEvents,
+          );
+          if (result) {
+            AppFlowyEditorLog.input.info(
+              'keyboard service onReplace - intercepted by interceptor: $interceptor',
+            );
+            return;
+          }
+        }
+
+        await onReplace(
+          replacement,
+          editorState,
+          widget.characterShortcutEvents,
+        );
+      },
+      onNonTextUpdate: (nonTextUpdate) async {
+        for (final interceptor in interceptors) {
+          final result = await interceptor.interceptNonTextUpdate(
+            nonTextUpdate,
+            editorState,
+            widget.characterShortcutEvents,
+          );
+          if (result) {
+            AppFlowyEditorLog.input.info(
+              'keyboard service onNonTextUpdate - intercepted by interceptor: $interceptor',
+            );
+            return;
+          }
+        }
+
+        await onNonTextUpdate(
+          nonTextUpdate,
+          editorState,
+          widget.characterShortcutEvents,
+        );
+      },
+      onPerformAction: (action) async {
+        for (final interceptor in interceptors) {
+          final result = await interceptor.interceptPerformAction(
+            action,
+            editorState,
+          );
+          if (result) {
+            AppFlowyEditorLog.input.info(
+              'keyboard service onPerformAction - intercepted by interceptor: $interceptor',
+            );
+            return;
+          }
+        }
+
+        await onPerformAction(
+          action,
+          editorState,
+        );
+      },
+      onFloatingCursor: (point) async {
+        for (final interceptor in interceptors) {
+          final result = await interceptor.interceptFloatingCursor(
+            point,
+            editorState,
+          );
+          if (result) {
+            AppFlowyEditorLog.input.info(
+              'keyboard service onFloatingCursor - intercepted by interceptor: $interceptor',
+            );
+            return;
+          }
+        }
+
+        await onFloatingCursorUpdate(
+          point,
+          editorState,
+        );
+      },
+      contentInsertionConfiguration: widget.contentInsertionConfiguration,
+    );
+  }
 }