/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include "APZCTreeManagerTester.h"
#include "APZTestCommon.h"
#include "InputUtils.h"
#include "mozilla/layers/LayersTypes.h"

class APZEventRegionsTester : public APZCTreeManagerTester {
 protected:
  UniquePtr<ScopedLayerTreeRegistration> registration;
  TestAsyncPanZoomController* rootApzc;

  void CreateEventRegionsLayerTree1() {
    const char* layerTreeSyntax = "c(tt)";
    nsIntRegion layerVisibleRegions[] = {
        nsIntRegion(IntRect(0, 0, 200, 200)),    // root
        nsIntRegion(IntRect(0, 0, 100, 200)),    // left half
        nsIntRegion(IntRect(0, 100, 200, 100)),  // bottom half
    };
    root = CreateLayerTree(layerTreeSyntax, layerVisibleRegions, nullptr, lm,
                           layers);
    SetScrollableFrameMetrics(root, ScrollableLayerGuid::START_SCROLL_ID);
    SetScrollableFrameMetrics(layers[1],
                              ScrollableLayerGuid::START_SCROLL_ID + 1);
    SetScrollableFrameMetrics(layers[2],
                              ScrollableLayerGuid::START_SCROLL_ID + 2);
    SetScrollHandoff(layers[1], root);
    SetScrollHandoff(layers[2], root);

    // Set up the event regions over a 200x200 area. The root layer has the
    // whole 200x200 as the hit region; layers[1] has the left half and
    // layers[2] has the bottom half. The bottom-left 100x100 area is also
    // in the d-t-c region for both layers[1] and layers[2] (but layers[2] is
    // on top so it gets the events by default if the main thread doesn't
    // respond).
    EventRegions regions(nsIntRegion(IntRect(0, 0, 200, 200)));
    root->SetEventRegions(regions);
    regions.mDispatchToContentHitRegion =
        nsIntRegion(IntRect(0, 100, 100, 100));
    regions.mHitRegion = nsIntRegion(IntRect(0, 0, 100, 200));
    layers[1]->SetEventRegions(regions);
    regions.mHitRegion = nsIntRegion(IntRect(0, 100, 200, 100));
    layers[2]->SetEventRegions(regions);

    registration = MakeUnique<ScopedLayerTreeRegistration>(manager, LayersId{0},
                                                           root, mcc);
    UpdateHitTestingTree();
    rootApzc = ApzcOf(root);
  }

  void CreateEventRegionsLayerTree2() {
    const char* layerTreeSyntax = "c(t)";
    nsIntRegion layerVisibleRegions[] = {
        nsIntRegion(IntRect(0, 0, 100, 500)),
        nsIntRegion(IntRect(0, 150, 100, 100)),
    };
    root = CreateLayerTree(layerTreeSyntax, layerVisibleRegions, nullptr, lm,
                           layers);
    SetScrollableFrameMetrics(root, ScrollableLayerGuid::START_SCROLL_ID);

    // Set up the event regions so that the child thebes layer is positioned far
    // away from the scrolling container layer.
    EventRegions regions(nsIntRegion(IntRect(0, 0, 100, 100)));
    root->SetEventRegions(regions);
    regions.mHitRegion = nsIntRegion(IntRect(0, 150, 100, 100));
    layers[1]->SetEventRegions(regions);

    registration = MakeUnique<ScopedLayerTreeRegistration>(manager, LayersId{0},
                                                           root, mcc);
    UpdateHitTestingTree();
    rootApzc = ApzcOf(root);
  }

  void CreateObscuringLayerTree() {
    const char* layerTreeSyntax = "c(c(t)t)";
    // LayerID                     0 1 2 3
    // 0 is the root.
    // 1 is a parent scrollable layer.
    // 2 is a child scrollable layer.
    // 3 is the Obscurer, who ruins everything.
    nsIntRegion layerVisibleRegions[] = {
        // x coordinates are uninteresting
        nsIntRegion(IntRect(0, 0, 200, 200)),   // [0, 200]
        nsIntRegion(IntRect(0, 0, 200, 200)),   // [0, 200]
        nsIntRegion(IntRect(0, 100, 200, 50)),  // [100, 150]
        nsIntRegion(IntRect(0, 100, 200, 100))  // [100, 200]
    };
    root = CreateLayerTree(layerTreeSyntax, layerVisibleRegions, nullptr, lm,
                           layers);

    SetScrollableFrameMetrics(root, ScrollableLayerGuid::START_SCROLL_ID,
                              CSSRect(0, 0, 200, 200));
    SetScrollableFrameMetrics(layers[1],
                              ScrollableLayerGuid::START_SCROLL_ID + 1,
                              CSSRect(0, 0, 200, 300));
    SetScrollableFrameMetrics(layers[2],
                              ScrollableLayerGuid::START_SCROLL_ID + 2,
                              CSSRect(0, 0, 200, 100));
    SetScrollHandoff(layers[2], layers[1]);
    SetScrollHandoff(layers[1], root);

    EventRegions regions(nsIntRegion(IntRect(0, 0, 200, 200)));
    root->SetEventRegions(regions);
    regions.mHitRegion = nsIntRegion(IntRect(0, 0, 200, 300));
    layers[1]->SetEventRegions(regions);
    regions.mHitRegion = nsIntRegion(IntRect(0, 100, 200, 100));
    layers[2]->SetEventRegions(regions);

    registration = MakeUnique<ScopedLayerTreeRegistration>(manager, LayersId{0},
                                                           root, mcc);
    UpdateHitTestingTree();
    rootApzc = ApzcOf(root);
  }

  void CreateBug1119497LayerTree() {
    const char* layerTreeSyntax = "c(tt)";
    // LayerID                     0 12
    // 0 is the root and has an APZC
    // 1 is behind 2 and has an APZC
    // 2 entirely covers 1 and should take all the input events, but has no APZC
    // so hits to 2 should go to to the root APZC
    nsIntRegion layerVisibleRegions[] = {
        nsIntRegion(IntRect(0, 0, 100, 100)),
        nsIntRegion(IntRect(0, 0, 100, 100)),
        nsIntRegion(IntRect(0, 0, 100, 100)),
    };
    root = CreateLayerTree(layerTreeSyntax, layerVisibleRegions, nullptr, lm,
                           layers);

    SetScrollableFrameMetrics(root, ScrollableLayerGuid::START_SCROLL_ID);
    SetScrollableFrameMetrics(layers[1],
                              ScrollableLayerGuid::START_SCROLL_ID + 1);

    registration = MakeUnique<ScopedLayerTreeRegistration>(manager, LayersId{0},
                                                           root, mcc);
    UpdateHitTestingTree();
  }

  void CreateBug1117712LayerTree() {
    const char* layerTreeSyntax = "c(c(t)t)";
    // LayerID                     0 1 2 3
    // 0 is the root
    // 1 is a container layer whose sole purpose to make a non-empty ancestor
    //   transform for 2, so that 2's screen-to-apzc and apzc-to-gecko
    //   transforms are different from 3's.
    // 2 is a small layer that is the actual target
    // 3 is a big layer obscuring 2 with a dispatch-to-content region
    nsIntRegion layerVisibleRegions[] = {
        nsIntRegion(IntRect(0, 0, 100, 100)),
        nsIntRegion(IntRect(0, 0, 0, 0)),
        nsIntRegion(IntRect(0, 0, 10, 10)),
        nsIntRegion(IntRect(0, 0, 100, 100)),
    };
    Matrix4x4 layerTransforms[] = {
        Matrix4x4(),
        Matrix4x4::Translation(50, 0, 0),
        Matrix4x4(),
        Matrix4x4(),
    };
    root = CreateLayerTree(layerTreeSyntax, layerVisibleRegions,
                           layerTransforms, lm, layers);

    SetScrollableFrameMetrics(layers[2], ScrollableLayerGuid::START_SCROLL_ID,
                              CSSRect(0, 0, 10, 10));
    SetScrollableFrameMetrics(layers[3],
                              ScrollableLayerGuid::START_SCROLL_ID + 1,
                              CSSRect(0, 0, 100, 100));
    SetScrollHandoff(layers[3], layers[2]);

    EventRegions regions(nsIntRegion(IntRect(0, 0, 10, 10)));
    layers[2]->SetEventRegions(regions);
    regions.mHitRegion = nsIntRegion(IntRect(0, 0, 100, 100));
    regions.mDispatchToContentHitRegion = nsIntRegion(IntRect(0, 0, 100, 100));
    layers[3]->SetEventRegions(regions);

    registration = MakeUnique<ScopedLayerTreeRegistration>(manager, LayersId{0},
                                                           root, mcc);
    UpdateHitTestingTree();
  }
};

TEST_F(APZEventRegionsTester, HitRegionImmediateResponse) {
  SCOPED_GFX_VAR(UseWebRender, bool, false);

  CreateEventRegionsLayerTree1();

  TestAsyncPanZoomController* root = ApzcOf(layers[0]);
  TestAsyncPanZoomController* left = ApzcOf(layers[1]);
  TestAsyncPanZoomController* bottom = ApzcOf(layers[2]);

  MockFunction<void(std::string checkPointName)> check;
  {
    InSequence s;
    EXPECT_CALL(*mcc, HandleTap(TapType::eSingleTap, _, _, left->GetGuid(), _))
        .Times(1);
    EXPECT_CALL(check, Call("Tapped on left"));
    EXPECT_CALL(*mcc,
                HandleTap(TapType::eSingleTap, _, _, bottom->GetGuid(), _))
        .Times(1);
    EXPECT_CALL(check, Call("Tapped on bottom"));
    EXPECT_CALL(*mcc, HandleTap(TapType::eSingleTap, _, _, root->GetGuid(), _))
        .Times(1);
    EXPECT_CALL(check, Call("Tapped on root"));
    EXPECT_CALL(check, Call("Tap pending on d-t-c region"));
    EXPECT_CALL(*mcc,
                HandleTap(TapType::eSingleTap, _, _, bottom->GetGuid(), _))
        .Times(1);
    EXPECT_CALL(check, Call("Tapped on bottom again"));
    EXPECT_CALL(*mcc, HandleTap(TapType::eSingleTap, _, _, left->GetGuid(), _))
        .Times(1);
    EXPECT_CALL(check, Call("Tapped on left this time"));
  }

  TimeDuration tapDuration = TimeDuration::FromMilliseconds(100);

  // Tap in the exposed hit regions of each of the layers once and ensure
  // the clicks are dispatched right away
  Tap(manager, ScreenIntPoint(10, 10), tapDuration);
  mcc->RunThroughDelayedTasks();  // this runs the tap event
  check.Call("Tapped on left");
  Tap(manager, ScreenIntPoint(110, 110), tapDuration);
  mcc->RunThroughDelayedTasks();  // this runs the tap event
  check.Call("Tapped on bottom");
  Tap(manager, ScreenIntPoint(110, 10), tapDuration);
  mcc->RunThroughDelayedTasks();  // this runs the tap event
  check.Call("Tapped on root");

  // Now tap on the dispatch-to-content region where the layers overlap
  Tap(manager, ScreenIntPoint(10, 110), tapDuration);
  mcc->RunThroughDelayedTasks();  // this runs the main-thread timeout
  check.Call("Tap pending on d-t-c region");
  mcc->RunThroughDelayedTasks();  // this runs the tap event
  check.Call("Tapped on bottom again");

  // Now let's do that again, but simulate a main-thread response
  uint64_t inputBlockId = 0;
  Tap(manager, ScreenIntPoint(10, 110), tapDuration, nullptr, &inputBlockId);
  nsTArray<ScrollableLayerGuid> targets;
  targets.AppendElement(left->GetGuid());
  manager->SetTargetAPZC(inputBlockId, targets);
  while (mcc->RunThroughDelayedTasks())
    ;  // this runs the tap event
  check.Call("Tapped on left this time");
}

TEST_F(APZEventRegionsTester, HitRegionAccumulatesChildren) {
  CreateEventRegionsLayerTree2();

  // Tap in the area of the child layer that's not directly included in the
  // parent layer's hit region. Verify that it comes out of the APZC's
  // content controller, which indicates the input events got routed correctly
  // to the APZC.
  EXPECT_CALL(*mcc,
              HandleTap(TapType::eSingleTap, _, _, rootApzc->GetGuid(), _))
      .Times(1);
  Tap(manager, ScreenIntPoint(10, 160), TimeDuration::FromMilliseconds(100));
}

TEST_F(APZEventRegionsTester, Obscuration) {
  SCOPED_GFX_VAR(UseWebRender, bool, false);

  CreateObscuringLayerTree();
  ScopedLayerTreeRegistration registration(manager, LayersId{0}, root, mcc);

  UpdateHitTestingTree();

  RefPtr<TestAsyncPanZoomController> parent = ApzcOf(layers[1]);
  TestAsyncPanZoomController* child = ApzcOf(layers[2]);

  Pan(parent, 75, 25, PanOptions::NoFling);

  APZCTreeManager::HitTestResult hit =
      manager->GetTargetAPZC(ScreenPoint(50, 75));
  EXPECT_EQ(child, hit.mTargetApzc.get());
  EXPECT_EQ(hit.mHitResult, CompositorHitTestFlags::eVisibleToHitTest);
}

TEST_F(APZEventRegionsTester, Bug1119497) {
  CreateBug1119497LayerTree();

  APZCTreeManager::HitTestResult hit =
      manager->GetTargetAPZC(ScreenPoint(50, 50));
  // We should hit layers[2], so |result| will be eVisibleToHitTest but there's
  // no actual APZC on layers[2], so it will be the APZC of the root layer.
  EXPECT_EQ(ApzcOf(layers[0]), hit.mTargetApzc.get());
  EXPECT_EQ(hit.mHitResult, CompositorHitTestFlags::eVisibleToHitTest);
}

TEST_F(APZEventRegionsTester, Bug1117712) {
  CreateBug1117712LayerTree();

  TestAsyncPanZoomController* apzc2 = ApzcOf(layers[2]);

  // These touch events should hit the dispatch-to-content region of layers[3]
  // and so get queued with that APZC as the tentative target.
  uint64_t inputBlockId = 0;
  Tap(manager, ScreenIntPoint(55, 5), TimeDuration::FromMilliseconds(100),
      nullptr, &inputBlockId);
  // But now we tell the APZ that really it hit layers[2], and expect the tap
  // to be delivered at the correct coordinates.
  EXPECT_CALL(*mcc, HandleTap(TapType::eSingleTap, LayoutDevicePoint(55, 5), 0,
                              apzc2->GetGuid(), _))
      .Times(1);

  nsTArray<ScrollableLayerGuid> targets;
  targets.AppendElement(apzc2->GetGuid());
  manager->SetTargetAPZC(inputBlockId, targets);
}

// Test that APZEventResult::mHandledResult is correctly
// populated.
TEST_F(APZEventRegionsTester, HandledByRootApzcFlag) {
  // Create simple layer tree containing a dispatch-to-content region
  // that covers part but not all of its area.
  const char* layerTreeSyntax = "c";
  nsIntRegion layerVisibleRegions[] = {
      nsIntRegion(IntRect(0, 0, 100, 100)),
  };
  root = CreateLayerTree(layerTreeSyntax, layerVisibleRegions, nullptr, lm,
                         layers);
  SetScrollableFrameMetrics(root, ScrollableLayerGuid::START_SCROLL_ID,
                            CSSRect(0, 0, 100, 200));
  ModifyFrameMetrics(root, [](ScrollMetadata& sm, FrameMetrics& metrics) {
    metrics.SetIsRootContent(true);
  });
  // away from the scrolling container layer.
  EventRegions regions(nsIntRegion(IntRect(0, 0, 100, 100)));
  // bottom half is dispatch-to-content
  regions.mDispatchToContentHitRegion = nsIntRegion(IntRect(0, 50, 100, 50));
  root->SetEventRegions(regions);
  registration =
      MakeUnique<ScopedLayerTreeRegistration>(manager, LayersId{0}, root, mcc);
  UpdateHitTestingTree();

  // Tap the top half and check that we report that the event was
  // handled by the root APZC.
  APZEventResult result =
      TouchDown(manager, ScreenIntPoint(50, 25), mcc->Time());
  TouchUp(manager, ScreenIntPoint(50, 25), mcc->Time());
  EXPECT_EQ(result.mHandledResult, Some(APZHandledResult::HandledByRoot));

  // Tap the bottom half and check that we report that we're not
  // sure whether the event was handled by the root APZC.
  result = TouchDown(manager, ScreenIntPoint(50, 75), mcc->Time());
  TouchUp(manager, ScreenIntPoint(50, 75), mcc->Time());
  EXPECT_EQ(result.mHandledResult, Nothing());

  // Register an input block callback that will tell us the
  // delayed answer.
  APZHandledResult delayedAnswer = APZHandledResult::Invalid;
  manager->AddInputBlockCallback(result.mInputBlockId,
                                 [&](uint64_t id, APZHandledResult answer) {
                                   EXPECT_EQ(id, result.mInputBlockId);
                                   delayedAnswer = answer;
                                 });

  // Send APZ the relevant notifications to allow it to process the
  // input block.
  manager->SetAllowedTouchBehavior(result.mInputBlockId,
                                   {AllowedTouchBehavior::VERTICAL_PAN});
  manager->SetTargetAPZC(result.mInputBlockId, {result.mTargetGuid});
  manager->ContentReceivedInputBlock(result.mInputBlockId,
                                     /*preventDefault=*/false);

  // Check that we received the delayed answer and it is what we expect.
  EXPECT_EQ(delayedAnswer, APZHandledResult::HandledByRoot);

  // Now repeat the tap on the bottom half, but simulate a prevent-default.
  // This time, we expect a delayed answer of `HandledByContent`.
  result = TouchDown(manager, ScreenIntPoint(50, 75), mcc->Time());
  TouchUp(manager, ScreenIntPoint(50, 75), mcc->Time());
  EXPECT_EQ(result.mHandledResult, Nothing());
  manager->AddInputBlockCallback(result.mInputBlockId,
                                 [&](uint64_t id, APZHandledResult answer) {
                                   EXPECT_EQ(id, result.mInputBlockId);
                                   delayedAnswer = answer;
                                 });
  manager->SetAllowedTouchBehavior(result.mInputBlockId,
                                   {AllowedTouchBehavior::VERTICAL_PAN});
  manager->SetTargetAPZC(result.mInputBlockId, {result.mTargetGuid});
  manager->ContentReceivedInputBlock(result.mInputBlockId,
                                     /*preventDefault=*/true);
  EXPECT_EQ(delayedAnswer, APZHandledResult::HandledByContent);

  // Shrink the scrollable area, now it's no longer scrollable.
  ModifyFrameMetrics(root, [](ScrollMetadata& sm, FrameMetrics& metrics) {
    metrics.SetScrollableRect(CSSRect(0, 0, 100, 100));
  });
  UpdateHitTestingTree();
  // Now repeat the tap on the bottom half with an event handler.
  // This time, we expect a delayed answer of `Unhandled`.
  result = TouchDown(manager, ScreenIntPoint(50, 75), mcc->Time());
  TouchUp(manager, ScreenIntPoint(50, 75), mcc->Time());
  EXPECT_EQ(result.mHandledResult, Nothing());
  manager->AddInputBlockCallback(result.mInputBlockId,
                                 [&](uint64_t id, APZHandledResult answer) {
                                   EXPECT_EQ(id, result.mInputBlockId);
                                   delayedAnswer = answer;
                                 });
  manager->SetAllowedTouchBehavior(result.mInputBlockId,
                                   {AllowedTouchBehavior::VERTICAL_PAN});
  manager->SetTargetAPZC(result.mInputBlockId, {result.mTargetGuid});
  manager->ContentReceivedInputBlock(result.mInputBlockId,
                                     /*preventDefault=*/false);
  EXPECT_EQ(delayedAnswer, APZHandledResult::Unhandled);
}