text: /*
   * Copyright (c) 2018-2020, Andreas Kling <kling@serenityos.org>
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *
   * 1. Redistributions of source code must retain the above copyright notice, this
   *    list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright notice,
   *    this list of conditions and the following disclaimer in the documentation
   *    and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #include <LibGfx/Painter.h>
  #include <LibWeb/CSS/StyleResolver.h>
  #include <LibWeb/Dump.h>
  #include <LibWeb/Layout/BlockBox.h>
  #include <LibWeb/Layout/InitialContainingBlockBox.h>
  #include <LibWeb/Layout/InlineFormattingContext.h>
  #include <LibWeb/Layout/ReplacedBox.h>
  #include <LibWeb/Layout/TextNode.h>
  
  namespace Web::Layout {
  
  BlockBox::BlockBox(DOM::Document& document, DOM::Node* node, NonnullRefPtr<CSS::StyleProperties> style)
      : Box(document, node, move(style))
  {
  }
  
  BlockBox::BlockBox(DOM::Document& document, DOM::Node* node, CSS::ComputedValues computed_values)
      : Box(document, node, move(computed_values))
  {
  }
  
  BlockBox::~BlockBox()
  {
  }
  
  bool BlockBox::should_clip_overflow() const
  {
      return computed_values().overflow_x() != CSS::Overflow::Visible && computed_values().overflow_y() != CSS::Overflow::Visible;
  }
  
  void BlockBox::paint(PaintContext& context, PaintPhase phase)
  {
      if (!is_visible())
          return;
  
      Box::paint(context, phase);
  
      if (!children_are_inline())
          return;
  
      if (should_clip_overflow()) {
          context.painter().save();
          // FIXME: Handle overflow-x and overflow-y being different values.
          context.painter().add_clip_rect(enclosing_int_rect(padded_rect()));
          context.painter().translate(-m_scroll_offset.to_type<int>());
      }
  
      for (auto& line_box : m_line_boxes) {
          for (auto& fragment : line_box.fragments()) {
              if (context.should_show_line_box_borders())
                  context.painter().draw_rect(enclosing_int_rect(fragment.absolute_rect()), Color::Green);
              fragment.paint(context, phase);
          }
      }
  
      if (should_clip_overflow()) {
          context.painter().restore();
      }
  
      // FIXME: Merge this loop with the above somehow..
      if (phase == PaintPhase::FocusOutline) {
          for (auto& line_box : m_line_boxes) {
              for (auto& fragment : line_box.fragments()) {
                  auto* node = fragment.layout_node().dom_node();
                  if (!node)
                      continue;
                  auto* parent = node->parent_element();
                  if (!parent)
                      continue;
                  if (parent->is_focused())
                      context.painter().draw_rect(enclosing_int_rect(fragment.absolute_rect()), context.palette().focus_outline());
              }
          }
      }
  }
  
  HitTestResult BlockBox::hit_test(const Gfx::IntPoint& position, HitTestType type) const
  {
      if (!children_are_inline())
          return Box::hit_test(position, type);
  
      HitTestResult last_good_candidate;
      for (auto& line_box : m_line_boxes) {
          for (auto& fragment : line_box.fragments()) {
              if (is<Box>(fragment.layout_node()) && downcast<Box>(fragment.layout_node()).stacking_context())
                  continue;
              if (enclosing_int_rect(fragment.absolute_rect()).contains(position)) {
                  if (is<BlockBox>(fragment.layout_node()))
                      return downcast<BlockBox>(fragment.layout_node()).hit_test(position, type);
                  return { fragment.layout_node(), fragment.text_index_at(position.x()) };
              }
              if (fragment.absolute_rect().top() <= position.y())
                  last_good_candidate = { fragment.layout_node(), fragment.text_index_at(position.x()) };
          }
      }
  
      if (type == HitTestType::TextCursor && last_good_candidate.layout_node)
          return last_good_candidate;
      return { absolute_rect().contains(position.x(), position.y()) ? this : nullptr };
  }
  
  void BlockBox::split_into_lines(InlineFormattingContext& context, LayoutMode layout_mode)
  {
      auto& containing_block = context.containing_block();
      auto* line_box = &containing_block.ensure_last_line_box();
  
      context.dimension_box_on_line(*this, layout_mode);
  
      float available_width = context.available_width_at_line(containing_block.line_boxes().size() - 1);
  
      if (layout_mode == LayoutMode::AllPossibleLineBreaks && line_box->width() > 0) {
          line_box = &containing_block.add_line_box();
      } else if (layout_mode == LayoutMode::Default && line_box->width() > 0 && line_box->width() + border_box_width() > available_width) {
          line_box = &containing_block.add_line_box();
      }
      line_box->add_fragment(*this, 0, 0, border_box_width(), height());
  }
  
  bool BlockBox::is_scrollable() const
  {
      // FIXME: Support horizontal scroll as well (overflow-x)
      return computed_values().overflow_y() == CSS::Overflow::Scroll;
  }
  
  void BlockBox::set_scroll_offset(const Gfx::FloatPoint& offset)
  {
      if (m_scroll_offset == offset)
          return;
      m_scroll_offset = offset;
      set_needs_display();
  }
  
  void BlockBox::handle_mousewheel(Badge<EventHandler>, const Gfx::IntPoint&, unsigned int, unsigned int, int wheel_delta)
  {
      if (!is_scrollable())
          return;
      auto new_offset = m_scroll_offset;
      new_offset.move_by(0, wheel_delta);
      set_scroll_offset(new_offset);
  }
  
  }
  