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

#include "ash/shelf/app_list_button.h"

#include "ash/ash_constants.h"
#include "ash/shelf/shelf_button.h"
#include "ash/shelf/shelf_button_host.h"
#include "ash/shelf/shelf_item_types.h"
#include "ash/shelf/shelf_layout_manager.h"
#include "ash/shelf/shelf_widget.h"
#include "ash/shell.h"
#include "base/command_line.h"
#include "grit/ash_resources.h"
#include "grit/ash_strings.h"
#include "ui/accessibility/ax_view_state.h"
#include "ui/app_list/app_list_switches.h"
#include "ui/base/l10n/l10n_util.h"
#include "ui/base/resource/resource_bundle.h"
#include "ui/base/ui_base_switches_util.h"
#include "ui/compositor/layer.h"
#include "ui/compositor/layer_animation_element.h"
#include "ui/compositor/layer_animation_sequence.h"
#include "ui/compositor/scoped_layer_animation_settings.h"
#include "ui/gfx/canvas.h"
#include "ui/gfx/image/image_skia_operations.h"
#include "ui/views/controls/button/image_button.h"
#include "ui/views/painter.h"

namespace ash {
// static
const int AppListButton::kImageBoundsSize = 7;


AppListButton::AppListButton(views::ButtonListener* listener,
                             ShelfButtonHost* host,
                             ShelfWidget* shelf_widget)
    : views::ImageButton(listener),
      draw_background_as_active_(false),
      host_(host),
      shelf_widget_(shelf_widget) {
  SetAccessibleName(
      app_list::switches::IsExperimentalAppListEnabled()
          ? l10n_util::GetStringUTF16(IDS_ASH_SHELF_APP_LIST_LAUNCHER_TITLE)
          : l10n_util::GetStringUTF16(IDS_ASH_SHELF_APP_LIST_TITLE));
  SetSize(gfx::Size(kShelfSize, kShelfSize));
  SetFocusPainter(views::Painter::CreateSolidFocusPainter(
                      kFocusBorderColor, gfx::Insets(1, 1, 1, 1)));
  set_notify_action(CustomButton::NOTIFY_ON_PRESS);
}

AppListButton::~AppListButton() {
}

bool AppListButton::OnMousePressed(const ui::MouseEvent& event) {
  ImageButton::OnMousePressed(event);
  host_->PointerPressedOnButton(this, ShelfButtonHost::MOUSE, event);
  return true;
}

void AppListButton::OnMouseReleased(const ui::MouseEvent& event) {
  ImageButton::OnMouseReleased(event);
  host_->PointerReleasedOnButton(this, ShelfButtonHost::MOUSE, false);
}

void AppListButton::OnMouseCaptureLost() {
  host_->PointerReleasedOnButton(this, ShelfButtonHost::MOUSE, true);
  ImageButton::OnMouseCaptureLost();
}

bool AppListButton::OnMouseDragged(const ui::MouseEvent& event) {
  ImageButton::OnMouseDragged(event);
  host_->PointerDraggedOnButton(this, ShelfButtonHost::MOUSE, event);
  return true;
}

void AppListButton::OnMouseMoved(const ui::MouseEvent& event) {
  ImageButton::OnMouseMoved(event);
  host_->MouseMovedOverButton(this);
}

void AppListButton::OnMouseEntered(const ui::MouseEvent& event) {
  ImageButton::OnMouseEntered(event);
  host_->MouseEnteredButton(this);
}

void AppListButton::OnMouseExited(const ui::MouseEvent& event) {
  ImageButton::OnMouseExited(event);
  host_->MouseExitedButton(this);
}

void AppListButton::OnGestureEvent(ui::GestureEvent* event) {
  switch (event->type()) {
   case ui::ET_GESTURE_SCROLL_BEGIN:
     if (switches::IsTouchFeedbackEnabled())
       SetDrawBackgroundAsActive(false);
     host_->PointerPressedOnButton(this, ShelfButtonHost::TOUCH, *event);
     event->SetHandled();
     return;
   case ui::ET_GESTURE_SCROLL_UPDATE:
     host_->PointerDraggedOnButton(this, ShelfButtonHost::TOUCH, *event);
     event->SetHandled();
     return;
   case ui::ET_GESTURE_SCROLL_END:
   case ui::ET_SCROLL_FLING_START:
     host_->PointerReleasedOnButton(this, ShelfButtonHost::TOUCH, false);
     event->SetHandled();
     return;
   case ui::ET_GESTURE_TAP_DOWN:
     if (switches::IsTouchFeedbackEnabled())
       SetDrawBackgroundAsActive(true);
     ImageButton::OnGestureEvent(event);
     break;
   case ui::ET_GESTURE_TAP_CANCEL:
   case ui::ET_GESTURE_TAP:
     if (switches::IsTouchFeedbackEnabled())
       SetDrawBackgroundAsActive(false);
     ImageButton::OnGestureEvent(event);
     break;
   default:
     ImageButton::OnGestureEvent(event);
     return;
  }
}

void AppListButton::OnPaint(gfx::Canvas* canvas) {
  // Call the base class first to paint any background/borders.
  View::OnPaint(canvas);

  int background_image_id = 0;
  if (Shell::GetInstance()->GetAppListTargetVisibility() ||
      draw_background_as_active_) {
    background_image_id = IDR_AURA_NOTIFICATION_BACKGROUND_PRESSED;
  } else {
    if (shelf_widget_->GetDimsShelf())
      background_image_id = IDR_AURA_NOTIFICATION_BACKGROUND_ON_BLACK;
    else
      background_image_id = IDR_AURA_NOTIFICATION_BACKGROUND_NORMAL;
  }
  ResourceBundle& rb = ResourceBundle::GetSharedInstance();
  const gfx::ImageSkia* background_image =
      rb.GetImageNamed(background_image_id).ToImageSkia();
  // TODO(mgiuca): When the "classic" app list is removed, also remove this
  // resource and its icon file.
  int foreground_image_id = app_list::switches::IsExperimentalAppListEnabled()
                                ? IDR_ASH_SHELF_ICON_APPLIST
                                : IDR_ASH_SHELF_ICON_APPLIST_CLASSIC;
  const gfx::ImageSkia* forground_image =
      rb.GetImageNamed(foreground_image_id).ToImageSkia();

  gfx::Rect contents_bounds = GetContentsBounds();
  gfx::Rect background_bounds, forground_bounds;

  ShelfAlignment alignment = shelf_widget_->GetAlignment();
  background_bounds.set_size(background_image->size());
  if (alignment == SHELF_ALIGNMENT_LEFT) {
    background_bounds.set_x(contents_bounds.width() -
        ShelfLayoutManager::kShelfItemInset - background_image->width());
    background_bounds.set_y(contents_bounds.y() +
        (contents_bounds.height() - background_image->height()) / 2);
  } else if(alignment == SHELF_ALIGNMENT_RIGHT) {
    background_bounds.set_x(ShelfLayoutManager::kShelfItemInset);
    background_bounds.set_y(contents_bounds.y() +
        (contents_bounds.height() - background_image->height()) / 2);
  } else {
    background_bounds.set_y(ShelfLayoutManager::kShelfItemInset);
    background_bounds.set_x(contents_bounds.x() +
        (contents_bounds.width() - background_image->width()) / 2);
  }

  forground_bounds.set_size(forground_image->size());
  forground_bounds.set_x(background_bounds.x() +
      std::max(0,
          (background_bounds.width() - forground_bounds.width()) / 2));
  forground_bounds.set_y(background_bounds.y() +
      std::max(0,
          (background_bounds.height() - forground_bounds.height()) / 2));

  canvas->DrawImageInt(*background_image,
                       background_bounds.x(),
                       background_bounds.y());
  canvas->DrawImageInt(*forground_image,
                       forground_bounds.x(),
                       forground_bounds.y());

  views::Painter::PaintFocusPainter(this, canvas, focus_painter());
}

void AppListButton::GetAccessibleState(ui::AXViewState* state) {
  state->role = ui::AX_ROLE_BUTTON;
  state->name = host_->GetAccessibleName(this);
}

void AppListButton::SetDrawBackgroundAsActive(
    bool draw_background_as_active) {
  if (draw_background_as_active_ == draw_background_as_active)
    return;
  draw_background_as_active_ = draw_background_as_active;
  SchedulePaint();
}

}  // namespace ash