// Copyright 2013 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/shelf_tooltip_manager.h"

#include "ash/shelf/shelf.h"
#include "ash/shelf/shelf_layout_manager.h"
#include "ash/shelf/shelf_view.h"
#include "ash/shell.h"
#include "ash/shell_window_ids.h"
#include "ash/wm/window_animations.h"
#include "base/bind.h"
#include "base/thread_task_runner_handle.h"
#include "base/time/time.h"
#include "ui/aura/window.h"
#include "ui/events/event.h"
#include "ui/events/event_constants.h"
#include "ui/gfx/geometry/insets.h"
#include "ui/views/bubble/bubble_delegate.h"
#include "ui/views/controls/label.h"
#include "ui/views/layout/fill_layout.h"
#include "ui/views/widget/widget.h"

namespace ash {
namespace {
const int kTooltipTopBottomMargin = 3;
const int kTooltipLeftRightMargin = 10;
const int kTooltipAppearanceDelay = 1000;  // msec
const int kTooltipMinHeight = 29 - 2 * kTooltipTopBottomMargin;
const SkColor kTooltipTextColor = SkColorSetRGB(0x22, 0x22, 0x22);

// The maximum width of the tooltip bubble.  Borrowed the value from
// ash/tooltip/tooltip_controller.cc
const int kTooltipMaxWidth = 250;

// The offset for the tooltip bubble - making sure that the bubble is flush
// with the shelf. The offset includes the arrow size in pixels as well as
// the activation bar and other spacing elements.
const int kArrowOffsetLeftRight = 11;
const int kArrowOffsetTopBottom = 7;

}  // namespace

// The implementation of tooltip of the launcher.
class ShelfTooltipManager::ShelfTooltipBubble
    : public views::BubbleDelegateView {
 public:
  ShelfTooltipBubble(views::View* anchor,
                     views::BubbleBorder::Arrow arrow,
                     const base::string16& text);

 private:
  // views::View overrides:
  gfx::Size GetPreferredSize() const override;

  DISALLOW_COPY_AND_ASSIGN(ShelfTooltipBubble);
};

ShelfTooltipManager::ShelfTooltipBubble::ShelfTooltipBubble(
    views::View* anchor,
    views::BubbleBorder::Arrow arrow,
    const base::string16& text)
    : views::BubbleDelegateView(anchor, arrow) {
  gfx::Insets insets = gfx::Insets(kArrowOffsetTopBottom,
                                   kArrowOffsetLeftRight);
  // Adjust the anchor location for asymmetrical borders of shelf item.
  if (anchor->border())
    insets += anchor->border()->GetInsets();

  set_anchor_view_insets(insets);
  set_close_on_esc(false);
  set_close_on_deactivate(false);
  set_can_activate(false);
  set_accept_events(false);
  set_margins(gfx::Insets(kTooltipTopBottomMargin, kTooltipLeftRightMargin));
  set_shadow(views::BubbleBorder::SMALL_SHADOW);
  SetLayoutManager(new views::FillLayout());
  // The anchor may not have the widget in tests.
  if (anchor->GetWidget() && anchor->GetWidget()->GetNativeWindow()) {
    set_parent_window(ash::Shell::GetContainer(
        anchor->GetWidget()->GetNativeWindow()->GetRootWindow(),
        ash::kShellWindowId_SettingBubbleContainer));
  }
  views::Label* label = new views::Label(text);
  label->SetHorizontalAlignment(gfx::ALIGN_LEFT);
  label->SetEnabledColor(kTooltipTextColor);
  AddChildView(label);
  views::BubbleDelegateView::CreateBubble(this);
  SizeToContents();
}

gfx::Size ShelfTooltipManager::ShelfTooltipBubble::GetPreferredSize() const {
  const gfx::Size size = views::BubbleDelegateView::GetPreferredSize();
  return gfx::Size(std::min(size.width(), kTooltipMaxWidth),
                   std::max(size.height(), kTooltipMinHeight));
}

ShelfTooltipManager::ShelfTooltipManager(ShelfView* shelf_view)
    : timer_delay_(kTooltipAppearanceDelay),
      shelf_view_(shelf_view),
      shelf_layout_manager_(nullptr),
      bubble_(nullptr),
      weak_factory_(this) {}

ShelfTooltipManager::~ShelfTooltipManager() {
  WillDeleteShelf();
}

void ShelfTooltipManager::Init() {
  shelf_layout_manager_ = shelf_view_->shelf()->shelf_layout_manager();
  shelf_layout_manager_->AddObserver(this);
  // TODO(msw): Capture events outside the shelf to close tooltips?
  shelf_view_->GetWidget()->GetNativeWindow()->AddPreTargetHandler(this);
}

void ShelfTooltipManager::Close() {
  timer_.Stop();
  if (bubble_)
    bubble_->GetWidget()->Close();
  bubble_ = nullptr;
}

bool ShelfTooltipManager::IsVisible() const {
  return bubble_ && bubble_->GetWidget()->IsVisible();
}

views::View* ShelfTooltipManager::GetCurrentAnchorView() const {
  return bubble_ ? bubble_->GetAnchorView() : nullptr;
}

void ShelfTooltipManager::ShowTooltip(views::View* view) {
  timer_.Stop();
  if (bubble_) {
    // Cancel the hiding animation to hide the old bubble immediately.
    gfx::NativeView native_view = bubble_->GetWidget()->GetNativeView();
    wm::SetWindowVisibilityAnimationTransition(native_view, wm::ANIMATE_NONE);
    Close();
  }

  if (shelf_layout_manager_ && !shelf_layout_manager_->IsVisible())
    return;

  Shelf* shelf = shelf_view_->shelf();
  views::BubbleBorder::Arrow arrow = shelf->SelectValueForShelfAlignment(
      views::BubbleBorder::BOTTOM_CENTER, views::BubbleBorder::LEFT_CENTER,
      views::BubbleBorder::RIGHT_CENTER, views::BubbleBorder::TOP_CENTER);

  base::string16 text = shelf_view_->GetTitleForView(view);
  bubble_ = new ShelfTooltipBubble(view, arrow, text);
  gfx::NativeView native_view = bubble_->GetWidget()->GetNativeView();
  wm::SetWindowVisibilityAnimationType(
      native_view, wm::WINDOW_VISIBILITY_ANIMATION_TYPE_VERTICAL);
  wm::SetWindowVisibilityAnimationTransition(native_view, wm::ANIMATE_HIDE);
  bubble_->GetWidget()->Show();
}

void ShelfTooltipManager::ShowTooltipWithDelay(views::View* view) {
  if (!shelf_layout_manager_ || shelf_layout_manager_->IsVisible()) {
    timer_.Start(FROM_HERE, base::TimeDelta::FromMilliseconds(timer_delay_),
                 base::Bind(&ShelfTooltipManager::ShowTooltip,
                            weak_factory_.GetWeakPtr(), view));
  }
}

void ShelfTooltipManager::OnEvent(ui::Event* event) {
  // Close the tooltip on mouse press or exit, and on most non-mouse events.
  if (event->type() == ui::ET_MOUSE_PRESSED ||
      event->type() == ui::ET_MOUSE_EXITED || !event->IsMouseEvent()) {
    if (!event->IsKeyEvent())
      Close();
    return;
  }

  gfx::Point point = static_cast<ui::LocatedEvent*>(event)->location();
  views::View::ConvertPointFromWidget(shelf_view_, &point);
  if (IsVisible() && shelf_view_->ShouldHideTooltip(point)) {
    Close();
    return;
  }

  views::View* view = shelf_view_->GetTooltipHandlerForPoint(point);
  const bool should_show = shelf_view_->ShouldShowTooltipForView(view);
  if (IsVisible() && bubble_->GetAnchorView() != view && should_show)
    ShowTooltip(view);

  if (!IsVisible() && event->type() == ui::ET_MOUSE_MOVED) {
    timer_.Stop();
    if (should_show)
      ShowTooltipWithDelay(view);
  }
}

void ShelfTooltipManager::WillDeleteShelf() {
  if (shelf_layout_manager_)
    shelf_layout_manager_->RemoveObserver(this);
  shelf_layout_manager_ = nullptr;

  views::Widget* widget = shelf_view_ ? shelf_view_->GetWidget() : nullptr;
  if (widget && widget->GetNativeWindow())
    widget->GetNativeWindow()->RemovePreTargetHandler(this);
  shelf_view_ = nullptr;
}

void ShelfTooltipManager::WillChangeVisibilityState(
    ShelfVisibilityState new_state) {
  if (new_state == SHELF_HIDDEN)
    Close();
}

void ShelfTooltipManager::OnAutoHideStateChanged(ShelfAutoHideState new_state) {
  if (new_state == SHELF_AUTO_HIDE_HIDDEN) {
    timer_.Stop();
    // AutoHide state change happens during an event filter, so immediate close
    // may cause a crash in the HandleMouseEvent() after the filter.  So we just
    // schedule the Close here.
    base::ThreadTaskRunnerHandle::Get()->PostTask(
        FROM_HERE,
        base::Bind(&ShelfTooltipManager::Close, weak_factory_.GetWeakPtr()));
  }
}

}  // namespace ash