servo/components/layout/table_rowgroup.rs

/* 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/. */

//! CSS table formatting contexts.

#![deny(unsafe_code)]

use app_units::Au;
use block::{BlockFlow, ISizeAndMarginsComputer};
use context::{LayoutContext, SharedLayoutContext};
use display_list_builder::DisplayListBuildState;
use euclid::Point2D;
use flow::{Flow, FlowClass, OpaqueFlow};
use fragment::{Fragment, FragmentBorderBoxIterator, Overflow};
use gfx::display_list::StackingContext;
use gfx_traits::ScrollRootId;
use gfx_traits::print_tree::PrintTree;
use layout_debug;
use serde::{Serialize, Serializer};
use std::fmt;
use std::iter::{IntoIterator, Iterator, Peekable};
use std::sync::Arc;
use style::computed_values::{border_collapse, border_spacing};
use style::context::SharedStyleContext;
use style::logical_geometry::LogicalSize;
use style::properties::ServoComputedValues;
use table::{ColumnIntrinsicInlineSize, InternalTable, TableLikeFlow};

/// A table formatting context.
pub struct TableRowGroupFlow {
    /// Fields common to all block flows.
    pub block_flow: BlockFlow,

    /// Information about the intrinsic inline-sizes of each column.
    pub column_intrinsic_inline_sizes: Vec<ColumnIntrinsicInlineSize>,

    /// The spacing for this rowgroup.
    pub spacing: border_spacing::T,

    /// The final width of the borders in the inline direction for each cell, computed by the
    /// entire table and pushed down into each row during inline size computation.
    pub collapsed_inline_direction_border_widths_for_table: Vec<Au>,

    /// The final width of the borders in the block direction for each cell, computed by the
    /// entire table and pushed down into each row during inline size computation.
    pub collapsed_block_direction_border_widths_for_table: Vec<Au>,
}

impl Serialize for TableRowGroupFlow {
    fn serialize<S: Serializer>(&self, serializer: &mut S) -> Result<(), S::Error> {
        self.block_flow.serialize(serializer)
    }
}

impl TableRowGroupFlow {
    pub fn from_fragment(fragment: Fragment) -> TableRowGroupFlow {
        TableRowGroupFlow {
            block_flow: BlockFlow::from_fragment(fragment),
            column_intrinsic_inline_sizes: Vec::new(),
            spacing: border_spacing::T {
                horizontal: Au(0),
                vertical: Au(0),
            },
            collapsed_inline_direction_border_widths_for_table: Vec::new(),
            collapsed_block_direction_border_widths_for_table: Vec::new(),
        }
    }

    pub fn populate_collapsed_border_spacing<'a, I>(
            &mut self,
            collapsed_inline_direction_border_widths_for_table: &[Au],
            collapsed_block_direction_border_widths_for_table: &mut Peekable<I>)
            where I: Iterator<Item=&'a Au> {
        self.collapsed_inline_direction_border_widths_for_table.clear();
        self.collapsed_inline_direction_border_widths_for_table
            .extend(collapsed_inline_direction_border_widths_for_table.into_iter().map(|x| *x));

        for _ in 0..self.block_flow.base.children.len() {
            if let Some(collapsed_block_direction_border_width_for_table) =
                    collapsed_block_direction_border_widths_for_table.next() {
                self.collapsed_block_direction_border_widths_for_table
                    .push(*collapsed_block_direction_border_width_for_table)
            }
        }
        if let Some(collapsed_block_direction_border_width_for_table) =
                collapsed_block_direction_border_widths_for_table.peek() {
            self.collapsed_block_direction_border_widths_for_table
                .push(**collapsed_block_direction_border_width_for_table)
        }
    }
}

impl Flow for TableRowGroupFlow {
    fn class(&self) -> FlowClass {
        FlowClass::TableRowGroup
    }

    fn as_mut_table_rowgroup(&mut self) -> &mut TableRowGroupFlow {
        self
    }

    fn as_table_rowgroup(&self) -> &TableRowGroupFlow {
        self
    }

    fn as_mut_block(&mut self) -> &mut BlockFlow {
        &mut self.block_flow
    }

    fn as_block(&self) -> &BlockFlow {
        &self.block_flow
    }

    fn bubble_inline_sizes(&mut self) {
        let _scope = layout_debug_scope!("table_rowgroup::bubble_inline_sizes {:x}",
                                         self.block_flow.base.debug_id());
        // Proper calculation of intrinsic sizes in table layout requires access to the entire
        // table, which we don't have yet. Defer to our parent.
    }

    /// Recursively (top-down) determines the actual inline-size of child contexts and fragments.
    /// When called on this context, the context has had its inline-size set by the parent context.
    fn assign_inline_sizes(&mut self, shared_context: &SharedStyleContext) {
        let _scope = layout_debug_scope!("table_rowgroup::assign_inline_sizes {:x}",
                                            self.block_flow.base.debug_id());
        debug!("assign_inline_sizes({}): assigning inline_size for flow", "table_rowgroup");

        // The position was set to the containing block by the flow's parent.
        let containing_block_inline_size = self.block_flow.base.block_container_inline_size;
        let (inline_start_content_edge, inline_end_content_edge) = (Au(0), Au(0));
        let content_inline_size = containing_block_inline_size;

        let border_collapse = self.block_flow.fragment.style.get_inheritedtable().border_collapse;
        let inline_size_computer = InternalTable {
            border_collapse: border_collapse,
        };
        inline_size_computer.compute_used_inline_size(&mut self.block_flow,
                                                      shared_context,
                                                      containing_block_inline_size);

        let collapsed_inline_direction_border_widths_for_table =
            &self.collapsed_inline_direction_border_widths_for_table;
        let mut collapsed_block_direction_border_widths_for_table =
            self.collapsed_block_direction_border_widths_for_table.iter().peekable();
        self.block_flow.propagate_assigned_inline_size_to_children(shared_context,
                                                                   inline_start_content_edge,
                                                                   inline_end_content_edge,
                                                                   content_inline_size,
                                                                   |child_flow,
                                                                    _child_index,
                                                                    _content_inline_size,
                                                                    _writing_mode,
                                                                    _inline_start_margin_edge,
                                                                    _inline_end_margin_edge| {
            if border_collapse == border_collapse::T::collapse {
                let child_table_row = child_flow.as_mut_table_row();
                child_table_row.populate_collapsed_border_spacing(
                    collapsed_inline_direction_border_widths_for_table,
                    &mut collapsed_block_direction_border_widths_for_table);
            }
        });
    }

    fn assign_block_size<'a>(&mut self, _: &'a LayoutContext<'a>) {
        debug!("assign_block_size: assigning block_size for table_rowgroup");
        self.block_flow.assign_block_size_for_table_like_flow(self.spacing.vertical)
    }

    fn compute_absolute_position(&mut self, layout_context: &SharedLayoutContext) {
        self.block_flow.compute_absolute_position(layout_context)
    }

    fn update_late_computed_inline_position_if_necessary(&mut self, inline_position: Au) {
        self.block_flow.update_late_computed_inline_position_if_necessary(inline_position)
    }

    fn update_late_computed_block_position_if_necessary(&mut self, block_position: Au) {
        self.block_flow.update_late_computed_block_position_if_necessary(block_position)
    }

    fn build_display_list(&mut self, state: &mut DisplayListBuildState) {
        debug!("build_display_list_table_rowgroup: same process as block flow");
        self.block_flow.build_display_list(state);
    }

    fn collect_stacking_contexts(&mut self,
                                 parent: &mut StackingContext,
                                 parent_scroll_root_id: ScrollRootId) {
        self.block_flow.collect_stacking_contexts(parent, parent_scroll_root_id);
    }

    fn repair_style(&mut self, new_style: &Arc<ServoComputedValues>) {
        self.block_flow.repair_style(new_style)
    }

    fn compute_overflow(&self) -> Overflow {
        self.block_flow.compute_overflow()
    }

    fn generated_containing_block_size(&self, flow: OpaqueFlow) -> LogicalSize<Au> {
        self.block_flow.generated_containing_block_size(flow)
    }

    fn iterate_through_fragment_border_boxes(&self,
                                             iterator: &mut FragmentBorderBoxIterator,
                                             level: i32,
                                             stacking_context_position: &Point2D<Au>) {
        self.block_flow.iterate_through_fragment_border_boxes(iterator, level, stacking_context_position)
    }

    fn mutate_fragments(&mut self, mutator: &mut FnMut(&mut Fragment)) {
        self.block_flow.mutate_fragments(mutator)
    }

    fn print_extra_flow_children(&self, print_tree: &mut PrintTree) {
        self.block_flow.print_extra_flow_children(print_tree);
    }
}

impl fmt::Debug for TableRowGroupFlow {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "TableRowGroupFlow: {:?}", self.block_flow)
    }
}