// Copyright 2014 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "remoting/host/chromeos/point_transformer.h"

#include "ash/display/mirror_window_controller.h"
#include "ash/display/window_tree_host_manager.h"
#include "ash/host/ash_window_tree_host.h"
#include "ash/shell.h"
#include "ash/wm/window_util.h"
#include "base/check.h"
#include "base/check_deref.h"
#include "ui/aura/window_tree_host.h"
#include "ui/display/display_finder.h"
#include "ui/display/display_layout.h"
#include "ui/display/manager/display_manager.h"
#include "ui/gfx/geometry/point_f.h"
#include "ui/wm/core/coordinate_conversion.h"

namespace remoting {

namespace {

gfx::PointF ConvertScreenDIPToWindowDIP(const aura::Window& window,
                                        gfx::PointF location_in_screen_in_dip) {
  gfx::PointF result(location_in_screen_in_dip);
  wm::ConvertPointFromScreen(&window, &result);
  return result;
}

gfx::PointF ConvertWindowDIPToScreenDIP(const aura::Window& window,
                                        gfx::PointF location_in_window_in_dip) {
  gfx::PointF result(location_in_window_in_dip);
  wm::ConvertPointToScreen(&window, &result);
  return result;
}

gfx::PointF ConvertWindowDIPtoWindowPixels(
    const aura::Window& window,
    gfx::PointF location_in_window_in_dip) {
  gfx::PointF result(location_in_window_in_dip);
  window.GetHost()->ConvertDIPToPixels(&result);
  return result;
}

gfx::PointF ConvertWindowPixelsToWindowDIP(
    const aura::Window& window,
    gfx::PointF location_in_window_in_pixels) {
  gfx::PointF result(location_in_window_in_pixels);
  window.GetHost()->ConvertPixelsToDIP(&result);
  return result;
}

gfx::PointF ConvertWindowPixelsToScreenPixels(
    const aura::Window& window,
    gfx::PointF location_in_window_in_pixels) {
  return location_in_window_in_pixels +
         window.GetHost()->GetBoundsInPixels().OffsetFromOrigin();
}

bool IsInUnifiedDesktop() {
  return ash::Shell::Get()->display_manager()->IsInUnifiedMode();
}

const display::Displays& PhysicalDisplaysInUnifiedDesktop() {
  return ash::Shell::Get()
      ->display_manager()
      ->software_mirroring_display_list();
}

const display::Display& NearestDisplayInUnifiedDesktop(gfx::PointF point) {
  const display::Display& display =
      CHECK_DEREF(display::FindDisplayNearestPoint(
          PhysicalDisplaysInUnifiedDesktop(), gfx::ToRoundedPoint(point)));
  CHECK(display.is_valid());
  return display;
}

const aura::Window& GetUnifiedDesktopRootWindowAt(gfx::PointF point) {
  const display::Display& display = NearestDisplayInUnifiedDesktop(point);
  aura::Window* window = ash::Shell::Get()
                             ->window_tree_host_manager()
                             ->mirror_window_controller()
                             ->GetAshWindowTreeHostForDisplayId(display.id())
                             ->AsWindowTreeHost()
                             ->window();
  return CHECK_DEREF(window);
}

const aura::Window& GetRootWindowAt(gfx::PointF point) {
  if (IsInUnifiedDesktop()) {
    return GetUnifiedDesktopRootWindowAt(point);
  }
  const aura::Window* window =
      ash::window_util::GetRootWindowAt(gfx::ToRoundedPoint(point));
  return CHECK_DEREF(window);
}

}  // namespace

// static
gfx::PointF PointTransformer::ConvertScreenInDipToScreenInPixel(
    gfx::PointF location_in_screen_in_dip) {
  const aura::Window& window = GetRootWindowAt(location_in_screen_in_dip);

  gfx::PointF location_in_window_in_dip =
      ConvertScreenDIPToWindowDIP(window, location_in_screen_in_dip);

  gfx::PointF location_in_window_in_pixels =
      ConvertWindowDIPtoWindowPixels(window, location_in_window_in_dip);

  gfx::PointF location_in_screen_in_pixel =
      ConvertWindowPixelsToScreenPixels(window, location_in_window_in_pixels);

  return location_in_screen_in_pixel;
}

// static
gfx::PointF PointTransformer::ConvertWindowInPixelToScreenInDip(
    const aura::Window& window,
    gfx::PointF location_in_window_in_pixels) {
  gfx::PointF location_in_window_in_dip =
      ConvertWindowPixelsToWindowDIP(window, location_in_window_in_pixels);

  gfx::PointF location_in_screen_in_dip =
      ConvertWindowDIPToScreenDIP(window, location_in_window_in_dip);

  return location_in_screen_in_dip;
}

}  // namespace remoting