// Copyright (c) 2016 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 "core/dom/Range.h"
#include "core/frame/FrameView.h"
#include "core/input/EventHandler.h"
#include "core/page/ChromeClient.h"
#include "core/page/ContextMenuController.h"
#include "core/page/FocusController.h"
#include "core/page/Page.h"
#include "platform/Cursor.h"
#include "platform/testing/URLTestHelpers.h"
#include "platform/testing/UnitTestHelpers.h"
#include "public/web/WebSettings.h"
#include "testing/gmock/include/gmock/gmock.h"
#include "testing/gtest/include/gtest/gtest.h"
#include "web/WebLocalFrameImpl.h"
#include "web/tests/FrameTestHelpers.h"

using ::testing::_;

namespace blink {

IntSize scaled(IntSize p, float scale) {
  p.scale(scale, scale);
  return p;
}

class LinkSelectionTestBase : public ::testing::Test {
 protected:
  enum DragFlag { SendDownEvent = 1, SendUpEvent = 1 << 1 };
  using DragFlags = unsigned;

  void emulateMouseDrag(const IntPoint& downPoint,
                        const IntPoint& upPoint,
                        int modifiers,
                        DragFlags = SendDownEvent | SendUpEvent);

  void emulateMouseClick(const IntPoint& clickPoint,
                         WebMouseEvent::Button,
                         int modifiers,
                         int count = 1);
  void emulateMouseDown(const IntPoint& clickPoint,
                        WebMouseEvent::Button,
                        int modifiers,
                        int count = 1);

  String getSelectionText();

  FrameTestHelpers::WebViewHelper m_helper;
  WebViewImpl* m_webView = nullptr;
  Persistent<WebLocalFrameImpl> m_mainFrame = nullptr;
};

void LinkSelectionTestBase::emulateMouseDrag(const IntPoint& downPoint,
                                             const IntPoint& upPoint,
                                             int modifiers,
                                             DragFlags dragFlags) {
  if (dragFlags & SendDownEvent) {
    const auto& downEvent = FrameTestHelpers::createMouseEvent(
        WebMouseEvent::MouseDown, WebMouseEvent::Button::Left, downPoint,
        modifiers);
    m_webView->handleInputEvent(downEvent);
  }

  const int kMoveEventsNumber = 10;
  const float kMoveIncrementFraction = 1. / kMoveEventsNumber;
  const auto& upDownVector = upPoint - downPoint;
  for (int i = 0; i < kMoveEventsNumber; ++i) {
    const auto& movePoint =
        downPoint + scaled(upDownVector, i * kMoveIncrementFraction);
    const auto& moveEvent = FrameTestHelpers::createMouseEvent(
        WebMouseEvent::MouseMove, WebMouseEvent::Button::Left, movePoint,
        modifiers);
    m_webView->handleInputEvent(moveEvent);
  }

  if (dragFlags & SendUpEvent) {
    const auto& upEvent = FrameTestHelpers::createMouseEvent(
        WebMouseEvent::MouseUp, WebMouseEvent::Button::Left, upPoint,
        modifiers);
    m_webView->handleInputEvent(upEvent);
  }
}

void LinkSelectionTestBase::emulateMouseClick(const IntPoint& clickPoint,
                                              WebMouseEvent::Button button,
                                              int modifiers,
                                              int count) {
  auto event = FrameTestHelpers::createMouseEvent(
      WebMouseEvent::MouseDown, button, clickPoint, modifiers);
  event.clickCount = count;
  m_webView->handleInputEvent(event);
  event.type = WebMouseEvent::MouseUp;
  m_webView->handleInputEvent(event);
}

void LinkSelectionTestBase::emulateMouseDown(const IntPoint& clickPoint,
                                             WebMouseEvent::Button button,
                                             int modifiers,
                                             int count) {
  auto event = FrameTestHelpers::createMouseEvent(
      WebMouseEvent::MouseDown, button, clickPoint, modifiers);
  event.clickCount = count;
  m_webView->handleInputEvent(event);
}

String LinkSelectionTestBase::getSelectionText() {
  return m_mainFrame->selectionAsText();
}

class TestFrameClient : public FrameTestHelpers::TestWebFrameClient {
 public:
  MOCK_METHOD4(loadURLExternally,
               void(const WebURLRequest&,
                    WebNavigationPolicy,
                    const WebString& downloadName,
                    bool shouldReplaceCurrentEntry));
};

class LinkSelectionTest : public LinkSelectionTestBase {
 protected:
  void SetUp() override {
    const char* const kHTMLString =
        "<a id='link' href='foo.com' style='font-size:20pt'>Text to select "
        "foobar</a>"
        "<div id='page_text'>Lorem ipsum dolor sit amet</div>";

    // We need to set deviceSupportsMouse setting to true and page's focus
    // controller to active so that FrameView can set the mouse cursor.
    m_webView = m_helper.initialize(
        false, &m_testFrameClient, nullptr, nullptr,
        [](WebSettings* settings) { settings->setDeviceSupportsMouse(true); });
    m_mainFrame = m_webView->mainFrameImpl();
    FrameTestHelpers::loadHTMLString(
        m_mainFrame, kHTMLString, URLTestHelpers::toKURL("http://foobar.com"));
    m_webView->resize(WebSize(800, 600));
    m_webView->page()->focusController().setActive(true);

    auto* document = m_mainFrame->frame()->document();
    ASSERT_NE(nullptr, document);
    auto* linkToSelect = document->getElementById("link")->firstChild();
    ASSERT_NE(nullptr, linkToSelect);
    // We get larger range that we actually want to select, because we need a
    // slightly larger rect to include the last character to the selection.
    const auto rangeToSelect =
        Range::create(*document, linkToSelect, 5, linkToSelect, 16);

    const auto& selectionRect = rangeToSelect->boundingBox();
    const auto& selectionRectCenterY = selectionRect.center().y();
    m_leftPointInLink = selectionRect.minXMinYCorner();
    m_leftPointInLink.setY(selectionRectCenterY);

    m_rightPointInLink = selectionRect.maxXMinYCorner();
    m_rightPointInLink.setY(selectionRectCenterY);
    m_rightPointInLink.move(-2, 0);
  }

  TestFrameClient m_testFrameClient;
  IntPoint m_leftPointInLink;
  IntPoint m_rightPointInLink;
};

TEST_F(LinkSelectionTest, MouseDragWithoutAltAllowNoLinkSelection) {
  emulateMouseDrag(m_leftPointInLink, m_rightPointInLink, 0);
  EXPECT_TRUE(getSelectionText().isEmpty());
}

TEST_F(LinkSelectionTest, MouseDragWithAltAllowSelection) {
  emulateMouseDrag(m_leftPointInLink, m_rightPointInLink,
                   WebInputEvent::AltKey);
  EXPECT_EQ("to select", getSelectionText());
}

TEST_F(LinkSelectionTest, HandCursorDuringLinkDrag) {
  emulateMouseDrag(m_rightPointInLink, m_leftPointInLink, 0, SendDownEvent);
  m_mainFrame->frame()->localFrameRoot()->eventHandler().scheduleCursorUpdate();
  testing::runDelayedTasks(50);
  const auto& cursor =
      m_mainFrame->frame()->chromeClient().lastSetCursorForTesting();
  EXPECT_EQ(Cursor::Hand, cursor.getType());
}

TEST_F(LinkSelectionTest, CaretCursorOverLinkDuringSelection) {
  emulateMouseDrag(m_rightPointInLink, m_leftPointInLink, WebInputEvent::AltKey,
                   SendDownEvent);
  m_mainFrame->frame()->localFrameRoot()->eventHandler().scheduleCursorUpdate();
  testing::runDelayedTasks(50);
  const auto& cursor =
      m_mainFrame->frame()->chromeClient().lastSetCursorForTesting();
  EXPECT_EQ(Cursor::IBeam, cursor.getType());
}

TEST_F(LinkSelectionTest, HandCursorOverLinkAfterContextMenu) {
  // Move mouse.
  emulateMouseDrag(m_rightPointInLink, m_leftPointInLink, 0, 0);

  // Show context menu. We don't send mouseup event here since in browser it
  // doesn't reach blink because of shown context menu.
  emulateMouseDown(m_leftPointInLink, WebMouseEvent::Button::Right, 0, 1);

  LocalFrame* frame = m_mainFrame->frame();
  // Hide context menu.
  frame->page()->contextMenuController().clearContextMenu();

  frame->localFrameRoot()->eventHandler().scheduleCursorUpdate();
  testing::runDelayedTasks(50);
  const auto& cursor =
      m_mainFrame->frame()->chromeClient().lastSetCursorForTesting();
  EXPECT_EQ(Cursor::Hand, cursor.getType());
}

TEST_F(LinkSelectionTest, SingleClickWithAltStartsDownload) {
  EXPECT_CALL(
      m_testFrameClient,
      loadURLExternally(_, WebNavigationPolicy::WebNavigationPolicyDownload,
                        WebString(), _));
  emulateMouseClick(m_leftPointInLink, WebMouseEvent::Button::Left,
                    WebInputEvent::AltKey);
}

TEST_F(LinkSelectionTest, SingleClickWithAltStartsDownloadWhenTextSelected) {
  auto* document = m_mainFrame->frame()->document();
  auto* textToSelect = document->getElementById("page_text")->firstChild();
  ASSERT_NE(nullptr, textToSelect);

  // Select some page text outside the link element.
  const Range* rangeToSelect =
      Range::create(*document, textToSelect, 1, textToSelect, 20);
  const auto& selectionRect = rangeToSelect->boundingBox();
  m_mainFrame->moveRangeSelection(selectionRect.minXMinYCorner(),
                                  selectionRect.maxXMaxYCorner());
  EXPECT_FALSE(getSelectionText().isEmpty());

  EXPECT_CALL(
      m_testFrameClient,
      loadURLExternally(_, WebNavigationPolicy::WebNavigationPolicyDownload,
                        WebString(), _));
  emulateMouseClick(m_leftPointInLink, WebMouseEvent::Button::Left,
                    WebInputEvent::AltKey);
}

class LinkSelectionClickEventsTest : public LinkSelectionTestBase {
 protected:
  class MockEventListener final : public EventListener {
   public:
    static MockEventListener* create() { return new MockEventListener(); }

    bool operator==(const EventListener& other) const final {
      return this == &other;
    }

    MOCK_METHOD2(handleEvent, void(ExecutionContext* executionContext, Event*));

   private:
    MockEventListener() : EventListener(CPPEventListenerType) {}
  };

  void SetUp() override {
    const char* const kHTMLString =
        "<div id='empty_div' style='width: 100px; height: 100px;'></div>"
        "<span id='text_div'>Sometexttoshow</span>";

    m_webView = m_helper.initialize(false);
    m_mainFrame = m_webView->mainFrameImpl();
    FrameTestHelpers::loadHTMLString(
        m_mainFrame, kHTMLString, URLTestHelpers::toKURL("http://foobar.com"));
    m_webView->resize(WebSize(800, 600));
    m_webView->page()->focusController().setActive(true);

    auto* document = m_mainFrame->frame()->document();
    ASSERT_NE(nullptr, document);

    auto* emptyDiv = document->getElementById("empty_div");
    auto* textDiv = document->getElementById("text_div");
    ASSERT_NE(nullptr, emptyDiv);
    ASSERT_NE(nullptr, textDiv);
  }

  void checkMouseClicks(Element& element, bool doubleClickEvent) {
    struct ScopedListenersCleaner {
      ScopedListenersCleaner(Element* element) : m_element(element) {}

      ~ScopedListenersCleaner() { m_element->removeAllEventListeners(); }

      Persistent<Element> m_element;
    } const listenersCleaner(&element);

    MockEventListener* eventHandler = MockEventListener::create();
    element.addEventListener(
        doubleClickEvent ? EventTypeNames::dblclick : EventTypeNames::click,
        eventHandler);

    ::testing::InSequence s;
    EXPECT_CALL(*eventHandler, handleEvent(_, _)).Times(1);

    const auto& elemBounds = element.boundsInViewport();
    const int clickCount = doubleClickEvent ? 2 : 1;
    emulateMouseClick(elemBounds.center(), WebMouseEvent::Button::Left, 0,
                      clickCount);

    if (doubleClickEvent) {
      EXPECT_EQ(element.innerText().isEmpty(), getSelectionText().isEmpty());
    }
  }
};

TEST_F(LinkSelectionClickEventsTest, SingleAndDoubleClickWillBeHandled) {
  auto* document = m_mainFrame->frame()->document();
  auto* element = document->getElementById("empty_div");

  {
    SCOPED_TRACE("Empty div, single click");
    checkMouseClicks(*element, false);
  }

  {
    SCOPED_TRACE("Empty div, double click");
    checkMouseClicks(*element, true);
  }

  element = document->getElementById("text_div");

  {
    SCOPED_TRACE("Text div, single click");
    checkMouseClicks(*element, false);
  }

  {
    SCOPED_TRACE("Text div, double click");
    checkMouseClicks(*element, true);
  }
}

}  // namespace blink