// Copyright 2019 The Cobalt Authors. All Rights Reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#include "cobalt/ui_navigation/interface.h"

#include "starboard/common/spin_lock.h"

namespace cobalt {
namespace ui_navigation {

namespace {

struct ItemImpl {
  explicit ItemImpl(NativeItemType type, const NativeCallbacks* callbacks,
                    void* callback_context)
      : type(type), callbacks(callbacks), callback_context(callback_context) {}

  starboard::SpinLock lock;

  const NativeItemType type;
  const NativeCallbacks* callbacks;
  void* callback_context;
  bool is_enabled = true;

  float content_offset_x = 0.0f;
  float content_offset_y = 0.0f;

  float scroll_top_lower_bound = 0.0f;
  float scroll_left_lower_bound = 0.0f;
  float scroll_top_upper_bound = 0.0f;
  float scroll_left_upper_bound = 0.0f;
};

NativeItem CreateItem(NativeItemType type, const NativeCallbacks* callbacks,
                      void* callback_context) {
  return reinterpret_cast<NativeItem>(
      new ItemImpl(type, callbacks, callback_context));
}

void DestroyItem(NativeItem item) { delete reinterpret_cast<ItemImpl*>(item); }

void SetItemBounds(NativeItem item, float scroll_top_lower_bound,
                   float scroll_left_lower_bound, float scroll_top_upper_bound,
                   float scroll_left_upper_bound) {
  ItemImpl* stub_item = reinterpret_cast<ItemImpl*>(item);
  if (stub_item->type == kNativeItemTypeContainer) {
    starboard::ScopedSpinLock scoped_lock(stub_item->lock);
    stub_item->scroll_top_lower_bound = scroll_top_lower_bound;
    stub_item->scroll_left_lower_bound = scroll_left_lower_bound;
    stub_item->scroll_top_upper_bound = scroll_top_upper_bound;
    stub_item->scroll_left_upper_bound = scroll_left_upper_bound;
  }
}

void GetItemBounds(NativeItem item, float* out_scroll_top_lower_bound,
                   float* out_scroll_left_lower_bound,
                   float* out_scroll_top_upper_bound,
                   float* out_scroll_left_upper_bound) {
  ItemImpl* stub_item = reinterpret_cast<ItemImpl*>(item);
  if (stub_item->type == kNativeItemTypeContainer) {
    starboard::ScopedSpinLock scoped_lock(stub_item->lock);
    *out_scroll_top_lower_bound = stub_item->scroll_top_lower_bound;
    *out_scroll_left_lower_bound = stub_item->scroll_left_lower_bound;
    *out_scroll_top_upper_bound = stub_item->scroll_top_upper_bound;
    *out_scroll_left_upper_bound = stub_item->scroll_left_upper_bound;
  }
}

void SetFocus(NativeItem item) {}

void SetItemEnabled(NativeItem item, bool enabled) {
  ItemImpl* stub_item = reinterpret_cast<ItemImpl*>(item);
  starboard::ScopedSpinLock scoped_lock(stub_item->lock);
  stub_item->is_enabled = enabled;
}

void SetItemDir(NativeItem item, NativeItemDir dir) {}

void SetItemFocusDuration(NativeItem item, float seconds) {}

void SetItemSize(NativeItem item, float width, float height) {}

void SetItemTransform(NativeItem item, const NativeMatrix2x3* transform) {}

bool GetItemFocusTransform(NativeItem item, NativeMatrix4* out_transform) {
  return false;
}

bool GetItemFocusVector(NativeItem item, float* out_x, float* out_y) {
  return false;
}

void SetItemContainerWindow(NativeItem item, SbWindow window) {}

void SetItemContainerItem(NativeItem item, NativeItem container) {}

void SetItemContentOffset(NativeItem item, float content_offset_x,
                          float content_offset_y) {
  ItemImpl* stub_item = reinterpret_cast<ItemImpl*>(item);
  if (stub_item->type != kNativeItemTypeContainer) {
    return;
  }
  starboard::ScopedSpinLock scoped_lock(stub_item->lock);
  const bool scroll_changed = stub_item->content_offset_x != content_offset_x ||
                              stub_item->content_offset_y != content_offset_y;
  if (!scroll_changed) {
    return;
  }
  stub_item->content_offset_x = content_offset_x;
  stub_item->content_offset_y = content_offset_y;
  if (stub_item->is_enabled) {
    stub_item->callbacks->onscroll(item, stub_item->callback_context);
  }
}

void GetItemContentOffset(NativeItem item, float* out_content_offset_x,
                          float* out_content_offset_y) {
  ItemImpl* stub_item = reinterpret_cast<ItemImpl*>(item);
  starboard::ScopedSpinLock scoped_lock(stub_item->lock);
  *out_content_offset_x = stub_item->content_offset_x;
  *out_content_offset_y = stub_item->content_offset_y;
}

void DoBatchUpdate(void (*update_function)(void*), void* context) {
  (*update_function)(context);
}

NativeInterface InitializeInterface() {
  NativeInterface interface = {0};
  SbUiNavInterface sb_ui_interface = {0};
  if (SbUiNavGetInterface(&sb_ui_interface)) {
    interface.create_item = sb_ui_interface.create_item;
    interface.destroy_item = sb_ui_interface.destroy_item;
    interface.set_item_bounds = nullptr;
    interface.get_item_bounds = nullptr;
    interface.set_focus = sb_ui_interface.set_focus;
    interface.set_item_enabled = sb_ui_interface.set_item_enabled;
    interface.set_item_dir = sb_ui_interface.set_item_dir;
    interface.set_item_size = sb_ui_interface.set_item_size;
    interface.set_item_transform = sb_ui_interface.set_item_transform;
    interface.get_item_focus_transform =
        sb_ui_interface.get_item_focus_transform;
    interface.get_item_focus_vector = sb_ui_interface.get_item_focus_vector;
    interface.set_item_container_window =
        sb_ui_interface.set_item_container_window;
    interface.set_item_container_item = sb_ui_interface.set_item_container_item;
    interface.set_item_content_offset = sb_ui_interface.set_item_content_offset;
    interface.get_item_content_offset = sb_ui_interface.get_item_content_offset;
#if SB_API_VERSION >= 13
    interface.set_item_focus_duration = sb_ui_interface.set_item_focus_duration;
    interface.do_batch_update = sb_ui_interface.do_batch_update;
#else
    interface.set_item_focus_duration = &SetItemFocusDuration;
    interface.do_batch_update = &DoBatchUpdate;
#endif
    return interface;
  }

  interface.create_item = &CreateItem;
  interface.destroy_item = &DestroyItem;
  interface.set_item_bounds = &SetItemBounds;
  interface.get_item_bounds = &GetItemBounds;
  interface.set_focus = &SetFocus;
  interface.set_item_enabled = &SetItemEnabled;
  interface.set_item_dir = &SetItemDir;
  interface.set_item_focus_duration = &SetItemFocusDuration;
  interface.set_item_size = &SetItemSize;
  interface.set_item_transform = &SetItemTransform;
  interface.get_item_focus_transform = &GetItemFocusTransform;
  interface.get_item_focus_vector = &GetItemFocusVector;
  interface.set_item_container_window = &SetItemContainerWindow;
  interface.set_item_container_item = &SetItemContainerItem;
  interface.set_item_content_offset = &SetItemContentOffset;
  interface.get_item_content_offset = &GetItemContentOffset;
  interface.do_batch_update = &DoBatchUpdate;
  return interface;
}

}  // namespace

const NativeInterface& GetInterface() {
  static NativeInterface s_interface = InitializeInterface();
  return s_interface;
}

}  // namespace ui_navigation
}  // namespace cobalt