// 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 "third_party/blink/renderer/core/paint/inline_flow_box_painter.h"

#include "third_party/blink/renderer/core/layout/api/line_layout_api_shim.h"
#include "third_party/blink/renderer/core/layout/line/inline_flow_box.h"
#include "third_party/blink/renderer/core/layout/line/root_inline_box.h"
#include "third_party/blink/renderer/core/paint/background_image_geometry.h"
#include "third_party/blink/renderer/core/paint/box_model_object_painter.h"
#include "third_party/blink/renderer/core/paint/box_painter_base.h"
#include "third_party/blink/renderer/core/paint/nine_piece_image_painter.h"
#include "third_party/blink/renderer/core/paint/paint_info.h"
#include "third_party/blink/renderer/platform/graphics/graphics_context_state_saver.h"
#include "third_party/blink/renderer/platform/graphics/paint/drawing_recorder.h"

namespace blink {

namespace {

inline Node* GetNode(const LayoutObject* box_model) {
  Node* node = nullptr;
  for (const LayoutObject* obj = box_model; obj && !node; obj = obj->Parent())
    node = obj->GeneratingNode();
  return node;
}

inline const LayoutBoxModelObject* GetBoxModelObject(
    const InlineFlowBox& flow_box) {
  return ToLayoutBoxModelObject(
      LineLayoutAPIShim::LayoutObjectFrom(flow_box.BoxModelObject()));
}

}  // anonymous namespace

InlineFlowBoxPainter::InlineFlowBoxPainter(const InlineFlowBox& flow_box)
    : InlineBoxPainterBase(
          *GetBoxModelObject(flow_box),
          &GetBoxModelObject(flow_box)->GetDocument(),
          GetNode(GetBoxModelObject(flow_box)),
          flow_box.GetLineLayoutItem().StyleRef(),
          flow_box.GetLineLayoutItem().StyleRef(flow_box.IsFirstLineStyle())),
      inline_flow_box_(flow_box) {
  object_has_multiple_boxes_ = inline_flow_box_.PrevForSameLayoutObject() ||
                               inline_flow_box_.NextForSameLayoutObject();
  bool force_include_logical_edges =
      (!inline_flow_box_.PrevForSameLayoutObject() &&
       !inline_flow_box_.NextForSameLayoutObject()) ||
      !inline_flow_box_.Parent();
  include_logical_left_edge_for_box_shadow_ =
      force_include_logical_edges || inline_flow_box_.IncludeLogicalLeftEdge();
  include_logical_right_edge_for_box_shadow_ =
      force_include_logical_edges || inline_flow_box_.IncludeLogicalRightEdge();
}

void InlineFlowBoxPainter::Paint(const PaintInfo& paint_info,
                                 const LayoutPoint& paint_offset,
                                 const LayoutUnit line_top,
                                 const LayoutUnit line_bottom) {
  DCHECK(!ShouldPaintSelfOutline(paint_info.phase) &&
         !ShouldPaintDescendantOutlines(paint_info.phase));

  LayoutRect overflow_rect(
      inline_flow_box_.VisualOverflowRect(line_top, line_bottom));
  inline_flow_box_.FlipForWritingMode(overflow_rect);
  overflow_rect.MoveBy(paint_offset);

  if (!paint_info.GetCullRect().IntersectsCullRect(overflow_rect))
    return;

  if (paint_info.phase == PaintPhase::kMask) {
    PaintMask(paint_info, paint_offset);
    return;
  }

  if (paint_info.phase == PaintPhase::kForeground) {
    // Paint our background, border and box-shadow.
    PaintBackgroundBorderShadow(paint_info, paint_offset);
  }

  // Paint our children.
  PaintInfo child_info(paint_info);
  for (InlineBox* curr = inline_flow_box_.FirstChild(); curr;
       curr = curr->NextOnLine()) {
    if (curr->GetLineLayoutItem().IsText() ||
        !curr->BoxModelObject().HasSelfPaintingLayer())
      curr->Paint(child_info, paint_offset, line_top, line_bottom);
  }
}

static LayoutRect ClipRectForNinePieceImageStrip(const InlineFlowBox& box,
                                                 const NinePieceImage& image,
                                                 const LayoutRect& paint_rect) {
  LayoutRect clip_rect(paint_rect);
  const ComputedStyle& style = box.GetLineLayoutItem().StyleRef();
  LayoutRectOutsets outsets = style.ImageOutsets(image);
  if (box.IsHorizontal()) {
    clip_rect.SetY(paint_rect.Y() - outsets.Top());
    clip_rect.SetHeight(paint_rect.Height() + outsets.Top() + outsets.Bottom());
    if (box.IncludeLogicalLeftEdge()) {
      clip_rect.SetX(paint_rect.X() - outsets.Left());
      clip_rect.SetWidth(paint_rect.Width() + outsets.Left());
    }
    if (box.IncludeLogicalRightEdge())
      clip_rect.SetWidth(clip_rect.Width() + outsets.Right());
  } else {
    clip_rect.SetX(paint_rect.X() - outsets.Left());
    clip_rect.SetWidth(paint_rect.Width() + outsets.Left() + outsets.Right());
    if (box.IncludeLogicalLeftEdge()) {
      clip_rect.SetY(paint_rect.Y() - outsets.Top());
      clip_rect.SetHeight(paint_rect.Height() + outsets.Top());
    }
    if (box.IncludeLogicalRightEdge())
      clip_rect.SetHeight(clip_rect.Height() + outsets.Bottom());
  }
  return clip_rect;
}

LayoutRect InlineFlowBoxPainter::PaintRectForImageStrip(
    const LayoutRect& paint_rect,
    TextDirection direction) const {
  // We have a fill/border/mask image that spans multiple lines.
  // We need to adjust the offset by the width of all previous lines.
  // Think of background painting on inlines as though you had one long line, a
  // single continuous strip. Even though that strip has been broken up across
  // multiple lines, you still paint it as though you had one single line. This
  // means each line has to pick up the background where the previous line left
  // off.
  LayoutUnit logical_offset_on_line;
  LayoutUnit total_logical_width;
  if (direction == TextDirection::kLtr) {
    for (const InlineFlowBox* curr = inline_flow_box_.PrevForSameLayoutObject();
         curr; curr = curr->PrevForSameLayoutObject())
      logical_offset_on_line += curr->LogicalWidth();
    total_logical_width = logical_offset_on_line;
    for (const InlineFlowBox* curr = &inline_flow_box_; curr;
         curr = curr->NextForSameLayoutObject())
      total_logical_width += curr->LogicalWidth();
  } else {
    for (const InlineFlowBox* curr = inline_flow_box_.NextForSameLayoutObject();
         curr; curr = curr->NextForSameLayoutObject())
      logical_offset_on_line += curr->LogicalWidth();
    total_logical_width = logical_offset_on_line;
    for (const InlineFlowBox* curr = &inline_flow_box_; curr;
         curr = curr->PrevForSameLayoutObject())
      total_logical_width += curr->LogicalWidth();
  }
  LayoutUnit strip_x =
      paint_rect.X() -
      (inline_flow_box_.IsHorizontal() ? logical_offset_on_line : LayoutUnit());
  LayoutUnit strip_y =
      paint_rect.Y() -
      (inline_flow_box_.IsHorizontal() ? LayoutUnit() : logical_offset_on_line);
  LayoutUnit strip_width = inline_flow_box_.IsHorizontal() ? total_logical_width
                                                           : paint_rect.Width();
  LayoutUnit strip_height = inline_flow_box_.IsHorizontal()
                                ? paint_rect.Height()
                                : total_logical_width;
  return LayoutRect(strip_x, strip_y, strip_width, strip_height);
}

InlineBoxPainterBase::BorderPaintingType
InlineFlowBoxPainter::GetBorderPaintType(const LayoutRect& adjusted_frame_rect,
                                         IntRect& adjusted_clip_rect) const {
  adjusted_clip_rect = PixelSnappedIntRect(adjusted_frame_rect);
  if (inline_flow_box_.Parent() &&
      inline_flow_box_.GetLineLayoutItem().StyleRef().HasBorderDecoration()) {
    const NinePieceImage& border_image =
        inline_flow_box_.GetLineLayoutItem().StyleRef().BorderImage();
    StyleImage* border_image_source = border_image.GetImage();
    bool has_border_image =
        border_image_source && border_image_source->CanRender();
    if (has_border_image && !border_image_source->IsLoaded())
      return kDontPaintBorders;

    // The simple case is where we either have no border image or we are the
    // only box for this object.  In those cases only a single call to draw is
    // required.
    if (!has_border_image || (!inline_flow_box_.PrevForSameLayoutObject() &&
                              !inline_flow_box_.NextForSameLayoutObject()))
      return kPaintBordersWithoutClip;

    // We have a border image that spans multiple lines.
    adjusted_clip_rect = PixelSnappedIntRect(ClipRectForNinePieceImageStrip(
        inline_flow_box_, border_image, adjusted_frame_rect));
    return kPaintBordersWithClip;
  }
  return kDontPaintBorders;
}

void InlineFlowBoxPainter::PaintBackgroundBorderShadow(
    const PaintInfo& paint_info,
    const LayoutPoint& paint_offset) {
  DCHECK(paint_info.phase == PaintPhase::kForeground);

  if (RuntimeEnabledFeatures::PaintTouchActionRectsEnabled())
    RecordHitTestData(paint_info, paint_offset);

  if (inline_flow_box_.GetLineLayoutItem().StyleRef().Visibility() !=
      EVisibility::kVisible)
    return;

  // You can use p::first-line to specify a background. If so, the root line
  // boxes for a line may actually have to paint a background.
  LayoutObject* inline_flow_box_layout_object =
      LineLayoutAPIShim::LayoutObjectFrom(inline_flow_box_.GetLineLayoutItem());
  bool should_paint_box_decoration_background;
  if (inline_flow_box_.Parent())
    should_paint_box_decoration_background =
        inline_flow_box_layout_object->HasBoxDecorationBackground();
  else
    should_paint_box_decoration_background =
        inline_flow_box_.IsFirstLineStyle() && line_style_ != style_;

  if (!should_paint_box_decoration_background)
    return;

  if (DrawingRecorder::UseCachedDrawingIfPossible(
          paint_info.context, inline_flow_box_,
          DisplayItem::kBoxDecorationBackground))
    return;

  DrawingRecorder recorder(paint_info.context, inline_flow_box_,
                           DisplayItem::kBoxDecorationBackground);

  LayoutRect paint_rect = AdjustedPaintRect(paint_offset);

  const auto& box_model = *ToLayoutBoxModelObject(
      LineLayoutAPIShim::LayoutObjectFrom(inline_flow_box_.BoxModelObject()));
  BackgroundImageGeometry geometry(box_model);
  BoxModelObjectPainter box_painter(box_model, &inline_flow_box_);
  PaintBoxDecorationBackground(box_painter, paint_info, paint_offset,
                               paint_rect, geometry,
                               inline_flow_box_.IncludeLogicalLeftEdge(),
                               inline_flow_box_.IncludeLogicalRightEdge());
}

void InlineFlowBoxPainter::PaintMask(const PaintInfo& paint_info,
                                     const LayoutPoint& paint_offset) {
  DCHECK_EQ(PaintPhase::kMask, paint_info.phase);
  const auto& box_model = *ToLayoutBoxModelObject(
      LineLayoutAPIShim::LayoutObjectFrom(inline_flow_box_.BoxModelObject()));
  if (!box_model.HasMask() ||
      box_model.StyleRef().Visibility() != EVisibility::kVisible)
    return;

  if (DrawingRecorder::UseCachedDrawingIfPossible(
          paint_info.context, inline_flow_box_,
          DisplayItem::PaintPhaseToDrawingType(paint_info.phase)))
    return;
  DrawingRecorder recorder(
      paint_info.context, inline_flow_box_,
      DisplayItem::PaintPhaseToDrawingType(paint_info.phase));

  LayoutRect paint_rect = AdjustedPaintRect(paint_offset);

  const auto& mask_nine_piece_image = box_model.StyleRef().MaskBoxImage();
  const auto* mask_box_image = mask_nine_piece_image.GetImage();

  // Figure out if we need to push a transparency layer to render our mask.
  BackgroundImageGeometry geometry(box_model);
  BoxModelObjectPainter box_painter(box_model, &inline_flow_box_);
  PaintFillLayers(box_painter, paint_info, Color::kTransparent,
                  box_model.StyleRef().MaskLayers(), paint_rect, geometry);

  bool has_box_image = mask_box_image && mask_box_image->CanRender();
  if (!has_box_image || !mask_box_image->IsLoaded()) {
    // Don't paint anything while we wait for the image to load.
    return;
  }

  // The simple case is where we are the only box for this object. In those
  // cases only a single call to draw is required.
  if (!inline_flow_box_.PrevForSameLayoutObject() &&
      !inline_flow_box_.NextForSameLayoutObject()) {
    NinePieceImagePainter::Paint(paint_info.context, box_model,
                                 box_model.GetDocument(), GetNode(&box_model),
                                 paint_rect, box_model.StyleRef(),
                                 mask_nine_piece_image);
  } else {
    // We have a mask image that spans multiple lines.
    // FIXME: What the heck do we do with RTL here? The math we're using is
    // obviously not right, but it isn't even clear how this should work at all.
    LayoutRect image_strip_paint_rect = PaintRectForImageStrip(
        LayoutRect(paint_rect.Location(), paint_rect.Size()),
        TextDirection::kLtr);
    FloatRect clip_rect(ClipRectForNinePieceImageStrip(
        inline_flow_box_, mask_nine_piece_image, paint_rect));
    GraphicsContextStateSaver state_saver(paint_info.context);
    // TODO(chrishtr): this should be pixel-snapped.
    paint_info.context.Clip(clip_rect);
    NinePieceImagePainter::Paint(paint_info.context, box_model,
                                 box_model.GetDocument(), GetNode(&box_model),
                                 image_strip_paint_rect, box_model.StyleRef(),
                                 mask_nine_piece_image);
  }
}

// This method should not be needed. See crbug.com/530659.
LayoutRect InlineFlowBoxPainter::FrameRectClampedToLineTopAndBottomIfNeeded()
    const {
  LayoutRect rect(inline_flow_box_.FrameRect());

  bool no_quirks_mode =
      inline_flow_box_.GetLineLayoutItem().GetDocument().InNoQuirksMode();
  if (!no_quirks_mode && !inline_flow_box_.HasTextChildren() &&
      !(inline_flow_box_.DescendantsHaveSameLineHeightAndBaseline() &&
        inline_flow_box_.HasTextDescendants())) {
    const RootInlineBox& root_box = inline_flow_box_.Root();
    LayoutUnit logical_top =
        inline_flow_box_.IsHorizontal() ? rect.Y() : rect.X();
    LayoutUnit logical_height =
        inline_flow_box_.IsHorizontal() ? rect.Height() : rect.Width();
    LayoutUnit bottom =
        std::min(root_box.LineBottom(), logical_top + logical_height);
    logical_top = std::max(root_box.LineTop(), logical_top);
    logical_height = bottom - logical_top;
    if (inline_flow_box_.IsHorizontal()) {
      rect.SetY(logical_top);
      rect.SetHeight(logical_height);
    } else {
      rect.SetX(logical_top);
      rect.SetWidth(logical_height);
    }
  }
  return rect;
}

LayoutRect InlineFlowBoxPainter::AdjustedPaintRect(
    const LayoutPoint& paint_offset) const {
  LayoutRect frame_rect = FrameRectClampedToLineTopAndBottomIfNeeded();
  LayoutRect local_rect(frame_rect);
  inline_flow_box_.FlipForWritingMode(local_rect);
  LayoutPoint adjusted_paint_offset = paint_offset + local_rect.Location();
  return LayoutRect(adjusted_paint_offset, frame_rect.Size());
}

void InlineFlowBoxPainter::RecordHitTestData(const PaintInfo& paint_info,
                                             const LayoutPoint& paint_offset) {
  LayoutObject* layout_object =
      LineLayoutAPIShim::LayoutObjectFrom(inline_flow_box_.GetLineLayoutItem());

  auto touch_action = layout_object->EffectiveWhitelistedTouchAction();
  if (touch_action == TouchAction::kTouchActionAuto)
    return;

  HitTestData::RecordTouchActionRect(
      paint_info.context, inline_flow_box_,
      TouchActionRect(AdjustedPaintRect(paint_offset), touch_action));
}

}  // namespace blink