// Copyright 2022 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef SRC_UI_A11Y_TESTING_FAKE_A11Y_MANAGER_H_
#define SRC_UI_A11Y_TESTING_FAKE_A11Y_MANAGER_H_

#include <fuchsia/accessibility/cpp/fidl.h>
#include <fuchsia/accessibility/semantics/cpp/fidl.h>
#include <lib/fidl/cpp/binding.h>
#include <lib/fidl/cpp/binding_set.h>

#include <memory>
#include <vector>

#include <test/accessibility/cpp/fidl.h>

#include "src/ui/a11y/lib/view/flatland_accessibility_view.h"

namespace a11y_testing {

// Trivial semantic tree implementation.
//
// This implementation keeps a semantic tree binding open for its lifetime, and
// responds success unconditionally when clients attempt to commit updates.
class FakeSemanticTree final : public fuchsia::accessibility::semantics::SemanticTree {
 public:
  explicit FakeSemanticTree(
      fuchsia::accessibility::semantics::SemanticListenerPtr semantic_listener);
  ~FakeSemanticTree() override = default;

  // |fuchsia::accessibility::semantics::SemanticTree|
  void CommitUpdates(CommitUpdatesCallback callback) override;

  // |fuchsia::accessibility::semantics::SemanticTree|
  void UpdateSemanticNodes(std::vector<fuchsia::accessibility::semantics::Node> nodes) override;

  // |fuchsia::accessibility::semantics::SemanticTree|
  void DeleteSemanticNodes(std::vector<uint32_t> node_ids) override;

  // |fuchsia::accessibility::semantics::SemanticTree|
  void SendSemanticEvent(::fuchsia::accessibility::semantics::SemanticEvent semantic_event,
                         SendSemanticEventCallback callback) override {
    ZX_PANIC("Not Implemented");
  }

  void Bind(fidl::InterfaceRequest<fuchsia::accessibility::semantics::SemanticTree>
                semantic_tree_request);

  void SetSemanticsEnabled(bool enabled);

 private:
  // Unused. We just need to hold onto the bound client end to prevent the peer
  // from receiving ZX_ERR_PEER_CLOSED.
  fuchsia::accessibility::semantics::SemanticListenerPtr semantic_listener_;
  fidl::Binding<fuchsia::accessibility::semantics::SemanticTree> semantic_tree_binding_;
};

class FakeMagnifier : public fuchsia::accessibility::Magnifier, test::accessibility::Magnifier {
 public:
  explicit FakeMagnifier(std::unique_ptr<a11y::FlatlandAccessibilityView> a11y_view);
  ~FakeMagnifier() override = default;

  // |fuchsia::accessibility::Magnifier|
  void RegisterHandler(
      fidl::InterfaceHandle<fuchsia::accessibility::MagnificationHandler> handler) override;

  // |test::accessibility::Magnifier|
  void SetMagnification(float scale, float translation_x, float translation_y,
                        SetMagnificationCallback callback) override;

  fidl::InterfaceRequestHandler<fuchsia::accessibility::Magnifier> GetMagnifierHandler();
  fidl::InterfaceRequestHandler<test::accessibility::Magnifier> GetTestMagnifierHandler();

 private:
  // Helper method to set the clip space transform.
  void SetMagnificationTransform();
  void WatchCallback(std::vector<fuchsia::ui::pointer::augment::TouchEventWithLocalHit> events);

  fidl::BindingSet<fuchsia::accessibility::Magnifier> magnifier_bindings_;
  fidl::BindingSet<test::accessibility::Magnifier> test_magnifier_bindings_;
  fuchsia::accessibility::MagnificationHandlerPtr handler_;

  std::unique_ptr<a11y::FlatlandAccessibilityView> a11y_view_;
  fuchsia::ui::pointer::augment::TouchSourceWithLocalHitPtr touch_source_;

  SetMagnificationCallback callback_ = {};

  float scale_ = 1.f;
  float translation_x_ = 0.f;
  float translation_y_ = 0.f;
};

// Trivial accessibility manager implementation.
//
// When a client registers a view for semantics, this class will bind the
// semantic tree and semantic listener channels in the request, and notify the
// client that semantics are disabled. This class will then hold the semantic
// tree and semantic listener channels open until the client closes them.
//
// The fake a11y manager is intended for uses cases where the semantics manager
// service is required, but no accessibility functionality is explicitly
// exercised (e.g. non-a11y tests that run chrome clients).
class FakeA11yManager : public fuchsia::accessibility::semantics::SemanticsManager {
 public:
  FakeA11yManager() = default;
  ~FakeA11yManager() override = default;

  fidl::InterfaceRequestHandler<fuchsia::accessibility::semantics::SemanticsManager> GetHandler();

  // |fuchsia::accessibility::semantics::SemanticsManager|
  void RegisterViewForSemantics(
      fuchsia::ui::views::ViewRef view_ref,
      fidl::InterfaceHandle<fuchsia::accessibility::semantics::SemanticListener> handle,
      fidl::InterfaceRequest<fuchsia::accessibility::semantics::SemanticTree> semantic_tree_request)
      override;

 private:
  fidl::BindingSet<fuchsia::accessibility::semantics::SemanticsManager> semantics_manager_bindings_;
  // We will never need to access any of the semantic trees, so we don't need to
  // associate them with their ViewRefs.
  //
  // Use a std::unique_ptr to prevent any of the FakeSemanticTrees from moving in
  // memory. I believe that would break their bindings, which refer
  // to their initial memory locations.
  std::vector<std::unique_ptr<FakeSemanticTree>> semantic_trees_;
};

}  // namespace a11y_testing

#endif  // SRC_UI_A11Y_TESTING_FAKE_A11Y_MANAGER_H_