2298d36bed
- Create Economist SubmissionTracking package correctly: * mainArticle = full blog post content * coverLetter = 216-word SIR— letter * Links to blog post via blogPostId - Archive 'Letter to The Economist' from blog posts (it's the cover letter) - Fix date display on article cards (use published_at) - Target publication already displaying via blue badge Database changes: - Make blogPostId optional in SubmissionTracking model - Economist package ID: 68fa85ae49d4900e7f2ecd83 - Le Monde package ID: 68fa2abd2e6acd5691932150 Next: Enhanced modal with tabs, validation, export 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
952 lines
43 KiB
Python
952 lines
43 KiB
Python
"""Layout for flex containers and flex-items."""
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import sys
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from math import inf, log10
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from ..css.properties import Dimension
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from ..formatting_structure import boxes
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from . import percent
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from .absolute import AbsolutePlaceholder, absolute_layout
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from .preferred import max_content_width, min_content_width, min_max
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from .table import find_in_flow_baseline, table_wrapper_width
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class FlexLine(list):
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"""Flex container line."""
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def flex_layout(context, box, bottom_space, skip_stack, containing_block, page_is_empty,
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absolute_boxes, fixed_boxes, discard):
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from . import block
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# TODO: merge this with block_container_layout.
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context.create_flex_formatting_context()
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resume_at = None
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is_start = skip_stack is None
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box.remove_decoration(start=not is_start, end=False)
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discard |= box.style['continue'] == 'discard'
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draw_bottom_decoration = discard or box.style['box_decoration_break'] == 'clone'
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row_gap, column_gap = box.style['row_gap'], box.style['column_gap']
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if draw_bottom_decoration:
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bottom_space += box.padding_bottom + box.border_bottom_width + box.margin_bottom
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if box.style['position'] == 'relative':
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# New containing block, use a new absolute list
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absolute_boxes = []
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# References are to: https://www.w3.org/TR/css-flexbox-1/#layout-algorithm.
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# 1 Initial setup, done in formatting_structure.build.
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# 2 Determine the available main and cross space for the flex items.
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if box.style['flex_direction'].startswith('row'):
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main, cross = 'width', 'height'
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else:
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main, cross = 'height', 'width'
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margin_left = 0 if box.margin_left == 'auto' else box.margin_left
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margin_right = 0 if box.margin_right == 'auto' else box.margin_right
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# Define available main space.
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# TODO: min- and max-content not implemented.
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if getattr(box, main) != 'auto':
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# If that dimension of the flex container’s content box is a definite size…
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available_main_space = getattr(box, main)
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else:
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# Otherwise, subtract the flex container’s margin, border, and padding…
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if main == 'width':
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available_main_space = (
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containing_block.width -
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margin_left - margin_right -
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box.padding_left - box.padding_right -
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box.border_left_width - box.border_right_width)
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else:
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available_main_space = inf
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# Same as above for available cross space.
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# TODO: min- and max-content not implemented.
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if getattr(box, cross) != 'auto':
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available_cross_space = getattr(box, cross)
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else:
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if cross == 'width':
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available_cross_space = (
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containing_block.width -
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margin_left - margin_right -
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box.padding_left - box.padding_right -
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box.border_left_width - box.border_right_width)
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else:
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available_cross_space = inf
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# 3 Determine the flex base size and hypothetical main size of each item.
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parent_box = box.copy()
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percent.resolve_percentages(parent_box, containing_block)
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block.block_level_width(parent_box, containing_block)
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children = sorted(box.children, key=lambda item: item.style['order'])
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original_skip_stack = skip_stack
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if skip_stack is not None:
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(skip, skip_stack), = skip_stack.items()
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if box.style['flex_direction'].endswith('-reverse'):
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children = children[:skip + 1]
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else:
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children = children[skip:]
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skip_stack = skip_stack
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else:
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skip, skip_stack = 0, None
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child_skip_stack = skip_stack
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if row_gap == 'normal':
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row_gap = 0
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elif row_gap.unit == '%':
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if box.height == 'auto':
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row_gap = 0
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else:
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row_gap = row_gap.value / 100 * box.height
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else:
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row_gap = row_gap.value
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if column_gap == 'normal':
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column_gap = 0
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elif column_gap.unit == '%':
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if box.width == 'auto':
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column_gap = 0
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else:
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column_gap = column_gap.value / 100 * box.width
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else:
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column_gap = column_gap.value
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if main == 'width':
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main_gap, cross_gap = column_gap, row_gap
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else:
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main_gap, cross_gap = row_gap, column_gap
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position_x = (
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parent_box.position_x + parent_box.border_left_width + parent_box.padding_left)
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if parent_box.margin_left != 'auto':
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position_x += parent_box.margin_left
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position_y = (
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parent_box.position_y + parent_box.border_top_width + parent_box.padding_top)
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if parent_box.margin_top != 'auto':
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position_y += parent_box.margin_top
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for index, child in enumerate(children):
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if not child.is_flex_item:
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# Absolute child layout: create placeholder.
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if child.is_absolutely_positioned():
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child.position_x = position_x
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child.position_y = position_y
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new_child = placeholder = AbsolutePlaceholder(child)
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placeholder.index = index
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children[index] = placeholder
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if child.style['position'] == 'absolute':
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absolute_boxes.append(placeholder)
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else:
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fixed_boxes.append(placeholder)
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elif child.is_running():
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running_name = child.style['position'][1]
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page = context.current_page
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context.running_elements[running_name][page].append(child)
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continue
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# See https://www.w3.org/TR/css-flexbox-1/#min-size-auto.
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if main == 'width':
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child_containing_block = (available_main_space, parent_box.height)
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else:
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child_containing_block = (parent_box.width, available_main_space)
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percent.resolve_percentages(child, child_containing_block)
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if child.is_table_wrapper:
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table_wrapper_width(context, child, child_containing_block)
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child.position_x = position_x
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child.position_y = position_y
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if child.style['min_width'] == 'auto':
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specified_size = child.width
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new_child = child.copy()
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new_child.style = child.style.copy()
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new_child.style['width'] = 'auto'
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new_child.style['min_width'] = Dimension(0, 'px')
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new_child.style['max_width'] = Dimension(inf, 'px')
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content_size = min_content_width(context, new_child, outer=False)
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transferred_size = None
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if isinstance(child, boxes.ReplacedBox):
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image = child.replacement
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_, intrinsic_height, intrinsic_ratio = image.get_intrinsic_size(
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child.style['image_resolution'], child.style['font_size'])
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if intrinsic_ratio and intrinsic_height:
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transferred_size = intrinsic_height * intrinsic_ratio
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content_size = max(
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child.min_width, min(child.max_width, content_size))
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if specified_size != 'auto':
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child.min_width = min(specified_size, content_size)
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elif transferred_size is not None:
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child.min_width = min(transferred_size, content_size)
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else:
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child.min_width = content_size
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if child.style['min_height'] == 'auto':
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# TODO: avoid calling block_level_layout, write min_content_height instead.
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specified_size = child.height
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new_child = child.copy()
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new_child.style = child.style.copy()
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new_child.style['height'] = 'auto'
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new_child.style['min_height'] = Dimension(0, 'px')
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new_child.style['max_height'] = Dimension(inf, 'px')
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if new_child.style['width'] == 'auto':
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new_child_width = max_content_width(context, new_child)
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new_child.style['width'] = Dimension(new_child_width, 'px')
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new_child = block.block_level_layout(
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context, new_child, bottom_space, child_skip_stack, parent_box,
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page_is_empty)[0]
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content_size = new_child.height if new_child else 0
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transferred_size = None
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if isinstance(child, boxes.ReplacedBox):
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image = child.replacement
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intrinsic_width, _, intrinsic_ratio = image.get_intrinsic_size(
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child.style['image_resolution'], child.style['font_size'])
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if intrinsic_ratio and intrinsic_width:
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transferred_size = intrinsic_width / intrinsic_ratio
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content_size = max(
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child.min_height, min(child.max_height, content_size))
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elif not intrinsic_width:
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# TODO: wrongly set by block_level_layout, would be OK with
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# min_content_height.
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content_size = 0
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if specified_size != 'auto':
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child.min_height = min(specified_size, content_size)
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elif transferred_size is not None:
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child.min_height = min(transferred_size, content_size)
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else:
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child.min_height = content_size
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if child.style['flex_basis'] == 'content':
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flex_basis = 'content'
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else:
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flex_basis = percent.percentage(
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child.style['flex_basis'], available_main_space)
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if flex_basis == 'auto':
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if (flex_basis := getattr(child, main)) == 'auto':
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flex_basis = 'content'
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# 3.A If the item has a definite used flex basis…
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if flex_basis != 'content':
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child.flex_base_size = flex_basis
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if main == 'width':
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child.main_outer_extra = (
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child.border_left_width + child.border_right_width +
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child.padding_left + child.padding_right)
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if child.margin_left != 'auto':
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child.main_outer_extra += child.margin_left
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if child.margin_right != 'auto':
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child.main_outer_extra += child.margin_right
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else:
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child.main_outer_extra = (
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child.border_top_width + child.border_bottom_width +
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child.padding_top + child.padding_bottom)
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if child.margin_top != 'auto':
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child.main_outer_extra += child.margin_top
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if child.margin_bottom != 'auto':
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child.main_outer_extra += child.margin_bottom
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elif False:
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# TODO: 3.B If the flex item has an intrinsic aspect ratio…
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# TODO: 3.C If the used flex basis is 'content'…
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# TODO: 3.D Otherwise, if the used flex basis is 'content'…
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pass
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else:
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# 3.E Otherwise…
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new_child = child.copy()
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new_child.style = child.style.copy()
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if main == 'width':
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# … the item’s min and max main sizes are ignored.
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new_child.style['min_width'] = Dimension(0, 'px')
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new_child.style['max_width'] = Dimension(inf, 'px')
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child.flex_base_size = max_content_width(
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context, new_child, outer=False)
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child.main_outer_extra = (
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max_content_width(context, child) - child.flex_base_size)
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else:
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# … the item’s min and max main sizes are ignored.
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new_child.style['min_height'] = Dimension(0, 'px')
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new_child.style['max_height'] = Dimension(inf, 'px')
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new_child.width = inf
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new_child, _, _, adjoining_margins, _, _ = block.block_level_layout(
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context, new_child, bottom_space, child_skip_stack, parent_box,
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page_is_empty, absolute_boxes, fixed_boxes)
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if new_child:
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# As flex items margins never collapse (with other flex items or
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# with the flex container), we can add the adjoining margins to the
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# child height.
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new_child.height += block.collapse_margin(adjoining_margins)
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child.flex_base_size = new_child.height
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child.main_outer_extra = (
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new_child.margin_height() - new_child.height)
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else:
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child.flex_base_size = child.main_outer_extra = 0
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if main == 'width':
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position_x += child.flex_base_size + child.main_outer_extra
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else:
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position_y += child.flex_base_size + child.main_outer_extra
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min_size = getattr(child, f'min_{main}')
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max_size = getattr(child, f'max_{main}')
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child.hypothetical_main_size = max(
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min_size, min(child.flex_base_size, max_size))
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# Skip stack is only for the first child.
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child_skip_stack = None
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# 4 Determine the main size of the flex container using the rules of the formatting
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# context in which it participates.
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if main == 'width':
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block.block_level_width(box, containing_block)
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else:
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if box.height == 'auto':
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box.height = 0
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flex_items = (child for child in children if child.is_flex_item)
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for i, child in enumerate(flex_items):
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box.height += child.hypothetical_main_size + child.main_outer_extra
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if i:
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box.height += main_gap
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box.height = max(box.min_height, min(box.height, box.max_height))
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# 5 If the flex container is single-line, collect all the flex items into a single
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# flex line.
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flex_lines = []
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line = []
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line_size = 0
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main_size = getattr(box, main)
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for i, child in enumerate(children, start=skip):
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if not child.is_flex_item:
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continue
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line_size += child.hypothetical_main_size + child.main_outer_extra
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if i > skip:
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line_size += main_gap
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if box.style['flex_wrap'] != 'nowrap' and line_size > main_size:
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if line:
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flex_lines.append(FlexLine(line))
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line = [(i, child)]
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line_size = child.hypothetical_main_size + child.main_outer_extra
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else:
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line.append((i, child))
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flex_lines.append(FlexLine(line))
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line = []
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line_size = 0
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else:
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line.append((i, child))
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if line:
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flex_lines.append(FlexLine(line))
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# TODO: Handle *-reverse using the terminology from the specification.
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if box.style['flex_wrap'] == 'wrap-reverse':
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flex_lines.reverse()
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if box.style['flex_direction'].endswith('-reverse'):
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for line in flex_lines:
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line.reverse()
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# 6 Resolve the flexible lengths of all the flex items to find their used main size.
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available_main_space = getattr(box, main)
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for line in flex_lines:
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# 9.7.1 Determine the used flex factor.
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hypothetical_main_size = sum(
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child.hypothetical_main_size + child.main_outer_extra
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for index, child in line)
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if hypothetical_main_size < available_main_space:
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flex_factor_type = 'grow'
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else:
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flex_factor_type = 'shrink'
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# 9.7.3 Size inflexible items.
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for index, child in line:
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if flex_factor_type == 'grow':
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child.flex_factor = child.style['flex_grow']
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flex_condition = child.flex_base_size > child.hypothetical_main_size
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else:
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child.flex_factor = child.style['flex_shrink']
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flex_condition = child.flex_base_size < child.hypothetical_main_size
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if child.flex_factor == 0 or flex_condition:
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child.target_main_size = child.hypothetical_main_size
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child.frozen = True
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else:
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child.frozen = False
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# 9.7.4 Calculate initial free space.
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initial_free_space = available_main_space
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for i, (index, child) in enumerate(line):
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if child.frozen:
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initial_free_space -= child.target_main_size + child.main_outer_extra
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else:
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initial_free_space -= child.flex_base_size + child.main_outer_extra
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if i:
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initial_free_space -= main_gap
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# 9.7.5.a Check for flexible items.
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while not all(child.frozen for index, child in line):
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unfrozen_factor_sum = 0
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remaining_free_space = available_main_space
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# 9.7.5.b Calculate the remaining free space.
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for i, (index, child) in enumerate(line):
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if child.frozen:
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remaining_free_space -= (
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child.target_main_size + child.main_outer_extra)
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else:
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remaining_free_space -= (
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child.flex_base_size + child.main_outer_extra)
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unfrozen_factor_sum += child.flex_factor
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if i:
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remaining_free_space -= main_gap
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if unfrozen_factor_sum < 1:
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initial_free_space *= unfrozen_factor_sum
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if initial_free_space == inf:
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initial_free_space = sys.maxsize
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if remaining_free_space == inf:
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remaining_free_space = sys.maxsize
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initial_magnitude = (
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int(log10(initial_free_space)) if initial_free_space > 0 else -inf)
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remaining_magnitude = (
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int(log10(remaining_free_space)) if remaining_free_space > 0 else -inf)
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if initial_magnitude < remaining_magnitude:
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remaining_free_space = initial_free_space
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# 9.7.5.c Distribute free space proportional to the flex factors.
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if remaining_free_space == 0:
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# If the remaining free space is zero: "Do nothing", but we at least set
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# the flex_base_size as target_main_size for next step.
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for index, child in line:
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if not child.frozen:
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child.target_main_size = child.flex_base_size
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else:
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scaled_flex_shrink_factors_sum = 0
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flex_grow_factors_sum = 0
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for index, child in line:
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if not child.frozen:
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child.scaled_flex_shrink_factor = (
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child.flex_base_size * child.style['flex_shrink'])
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scaled_flex_shrink_factors_sum += (
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child.scaled_flex_shrink_factor)
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flex_grow_factors_sum += child.style['flex_grow']
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for index, child in line:
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if not child.frozen:
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# If using the flex grow factor…
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if flex_factor_type == 'grow':
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ratio = child.style['flex_grow'] / flex_grow_factors_sum
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child.target_main_size = (
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child.flex_base_size + remaining_free_space * ratio)
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# If using the flex shrink factor…
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elif flex_factor_type == 'shrink':
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if scaled_flex_shrink_factors_sum == 0:
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child.target_main_size = child.flex_base_size
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else:
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ratio = (
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child.scaled_flex_shrink_factor /
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scaled_flex_shrink_factors_sum)
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child.target_main_size = (
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child.flex_base_size + remaining_free_space * ratio)
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child.target_main_size = min_max(child, child.target_main_size)
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# 9.7.5.d Fix min/max violations.
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for index, child in line:
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child.adjustment = 0
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if not child.frozen:
|
||
min_size = getattr(child, f'min_{main}')
|
||
max_size = getattr(child, f'max_{main}')
|
||
min_size = max(min_size , min(child.target_main_size, max_size))
|
||
if child.target_main_size < min_size:
|
||
child.adjustment = min_size - child.target_main_size
|
||
child.target_main_size = min_size
|
||
|
||
# 9.7.5.e Freeze over-flexed items.
|
||
adjustments = sum(child.adjustment for index, child in line)
|
||
for index, child in line:
|
||
# Zero: Freeze all items.
|
||
if adjustments == 0:
|
||
child.frozen = True
|
||
# Positive: Freeze all the items with min violations.
|
||
elif adjustments > 0 and child.adjustment > 0:
|
||
child.frozen = True
|
||
# Negative: Freeze all the items with max violations.
|
||
elif adjustments < 0 and child.adjustment < 0:
|
||
child.frozen = True
|
||
|
||
# 9.7.6 Set each item’s used main size to its target main size.
|
||
for index, child in line:
|
||
if main == 'width':
|
||
child.width = child.target_main_size
|
||
else:
|
||
child.height = child.target_main_size
|
||
|
||
# 7 Determine the hypothetical cross size of each item.
|
||
# TODO: Handle breaks.
|
||
new_flex_lines = []
|
||
child_skip_stack = skip_stack
|
||
for line in flex_lines:
|
||
new_flex_line = FlexLine()
|
||
for index, child in line:
|
||
# TODO: Fix this value, see test_flex_item_auto_margin_cross.
|
||
if child.margin_top == 'auto':
|
||
child.margin_top = 0
|
||
if child.margin_bottom == 'auto':
|
||
child.margin_bottom = 0
|
||
# TODO: Find another way than calling block_level_layout_switch.
|
||
new_child = child.copy()
|
||
new_child, _, _, adjoining_margins, _, _ = block.block_level_layout_switch(
|
||
context, new_child, -inf, child_skip_stack, parent_box, page_is_empty,
|
||
absolute_boxes, fixed_boxes, [], discard, None)
|
||
child._baseline = find_in_flow_baseline(new_child) or 0
|
||
if cross == 'height':
|
||
child.height = new_child.height
|
||
# As flex items margins never collapse (with other flex items or
|
||
# with the flex container), we can add the adjoining margins to the
|
||
# child height.
|
||
child.height += block.collapse_margin(adjoining_margins)
|
||
else:
|
||
if child.width == 'auto':
|
||
min_width = min_content_width(context, child, outer=False)
|
||
max_width = max_content_width(context, child, outer=False)
|
||
child.width = min(max(min_width, new_child.width), max_width)
|
||
else:
|
||
child.width = new_child.width
|
||
|
||
new_flex_line.append((index, child))
|
||
|
||
# Skip stack is only for the first child.
|
||
child_skip_stack = None
|
||
|
||
if new_flex_line:
|
||
new_flex_lines.append(new_flex_line)
|
||
flex_lines = new_flex_lines
|
||
|
||
# 8 Calculate the cross size of each flex line.
|
||
cross_size = getattr(box, cross)
|
||
if len(flex_lines) == 1 and cross_size != 'auto':
|
||
# If the flex container is single-line…
|
||
flex_lines[0].cross_size = cross_size
|
||
else:
|
||
# Otherwise, for each flex line…
|
||
# 8.1 Collect all the flex items whose inline-axis is parallel to the main-axis…
|
||
for line in flex_lines:
|
||
collected_items = []
|
||
not_collected_items = []
|
||
for index, child in line:
|
||
align_self = child.style['align_self']
|
||
collect = (
|
||
box.style['flex_direction'].startswith('row') and
|
||
'baseline' in align_self and
|
||
'auto' not in (child.margin_top, child.margin_bottom))
|
||
(collected_items if collect else not_collected_items).append(child)
|
||
cross_start_distance = cross_end_distance = 0
|
||
for child in collected_items:
|
||
baseline = child._baseline - child.position_y
|
||
cross_start_distance = max(cross_start_distance, baseline)
|
||
cross_end_distance = max(
|
||
cross_end_distance, child.margin_height() - baseline)
|
||
collected_cross_size = cross_start_distance + cross_end_distance
|
||
non_collected_cross_size = 0
|
||
# 8.2 Find the largest outer hypothetical cross size.
|
||
if not_collected_items:
|
||
non_collected_cross_size = -inf
|
||
for child in not_collected_items:
|
||
if cross == 'height':
|
||
child_cross_size = child.border_height()
|
||
if child.margin_top != 'auto':
|
||
child_cross_size += child.margin_top
|
||
if child.margin_bottom != 'auto':
|
||
child_cross_size += child.margin_bottom
|
||
else:
|
||
child_cross_size = child.border_width()
|
||
if child.margin_left != 'auto':
|
||
child_cross_size += child.margin_left
|
||
if child.margin_right != 'auto':
|
||
child_cross_size += child.margin_right
|
||
non_collected_cross_size = max(
|
||
child_cross_size, non_collected_cross_size)
|
||
# 8.3 Set the used cross-size of the flex line.
|
||
line.cross_size = max(collected_cross_size, non_collected_cross_size)
|
||
|
||
# 8.3 If the flex container is single-line…
|
||
if len(flex_lines) == 1:
|
||
line, = flex_lines
|
||
min_cross_size = getattr(box, f'min_{cross}')
|
||
if min_cross_size == 'auto':
|
||
min_cross_size = -inf
|
||
max_cross_size = getattr(box, f'max_{cross}')
|
||
if max_cross_size == 'auto':
|
||
max_cross_size = inf
|
||
line.cross_size = max(min_cross_size, min(line.cross_size, max_cross_size))
|
||
|
||
# 9 Handle 'align-content: stretch'.
|
||
align_content = box.style['align_content']
|
||
if 'normal' in align_content:
|
||
align_content = ('stretch',)
|
||
if 'stretch' in align_content:
|
||
definite_cross_size = None
|
||
if cross == 'height' and box.height != 'auto':
|
||
definite_cross_size = box.height
|
||
elif cross == 'width':
|
||
if isinstance(box, boxes.FlexBox):
|
||
if box.width == 'auto':
|
||
definite_cross_size = available_cross_space
|
||
else:
|
||
definite_cross_size = box.width
|
||
if definite_cross_size is not None:
|
||
extra_cross_size = definite_cross_size
|
||
extra_cross_size -= sum(line.cross_size for line in flex_lines)
|
||
extra_cross_size -= (len(flex_lines) - 1) * cross_gap
|
||
if extra_cross_size:
|
||
for line in flex_lines:
|
||
line.cross_size += extra_cross_size / len(flex_lines)
|
||
|
||
# TODO: 10 Collapse 'visibility: collapse' items.
|
||
|
||
# 11 Determine the used cross size of each flex item.
|
||
align_items = box.style['align_items']
|
||
if 'normal' in align_items:
|
||
align_items = ('stretch',)
|
||
for line in flex_lines:
|
||
for index, child in line:
|
||
align_self = child.style['align_self']
|
||
if 'normal' in align_self:
|
||
align_self = ('stretch',)
|
||
elif 'auto' in align_self:
|
||
align_self = align_items
|
||
if 'stretch' in align_self and child.style[cross] == 'auto':
|
||
cross_margins = (
|
||
(child.style['margin_top'], child.style['margin_bottom'])
|
||
if cross == 'height' else
|
||
(child.style['margin_left'], child.style['margin_right']))
|
||
if 'auto' not in cross_margins:
|
||
cross_size = line.cross_size
|
||
if cross == 'height':
|
||
cross_size -= (
|
||
child.margin_top + child.margin_bottom +
|
||
child.padding_top + child.padding_bottom +
|
||
child.border_top_width +
|
||
child.border_bottom_width)
|
||
else:
|
||
cross_size -= (
|
||
child.margin_left + child.margin_right +
|
||
child.padding_left + child.padding_right +
|
||
child.border_left_width +
|
||
child.border_right_width)
|
||
setattr(child, cross, cross_size)
|
||
# else: Cross size has been set by step 7.
|
||
|
||
# 12 Distribute any remaining free space.
|
||
original_position_main = (
|
||
box.content_box_x() if main == 'width'
|
||
else box.content_box_y())
|
||
justify_content = box.style['justify_content']
|
||
if 'normal' in justify_content:
|
||
justify_content = ('flex-start',)
|
||
if box.style['flex_direction'].endswith('-reverse'):
|
||
if 'flex-start' in justify_content:
|
||
justify_content = ('flex-end',)
|
||
elif 'flex-end' in justify_content:
|
||
justify_content = ('flex-start',)
|
||
elif 'start' in justify_content:
|
||
justify_content = ('end',)
|
||
elif 'end' in justify_content:
|
||
justify_content = ('start',)
|
||
|
||
for line in flex_lines:
|
||
position_main = original_position_main
|
||
if main == 'width':
|
||
free_space = box.width
|
||
for index, child in line:
|
||
free_space -= child.border_width()
|
||
if child.margin_left != 'auto':
|
||
free_space -= child.margin_left
|
||
if child.margin_right != 'auto':
|
||
free_space -= child.margin_right
|
||
else:
|
||
free_space = box.height
|
||
for index, child in line:
|
||
free_space -= child.border_height()
|
||
if child.margin_top != 'auto':
|
||
free_space -= child.margin_top
|
||
if child.margin_bottom != 'auto':
|
||
free_space -= child.margin_bottom
|
||
free_space -= (len(line) - 1) * main_gap
|
||
|
||
# 12.1 If the remaining free space is positive…
|
||
margins = 0
|
||
for index, child in line:
|
||
if main == 'width':
|
||
if child.margin_left == 'auto':
|
||
margins += 1
|
||
if child.margin_right == 'auto':
|
||
margins += 1
|
||
else:
|
||
if child.margin_top == 'auto':
|
||
margins += 1
|
||
if child.margin_bottom == 'auto':
|
||
margins += 1
|
||
if margins:
|
||
free_space /= margins
|
||
for index, child in line:
|
||
if main == 'width':
|
||
if child.margin_left == 'auto':
|
||
child.margin_left = free_space
|
||
if child.margin_right == 'auto':
|
||
child.margin_right = free_space
|
||
else:
|
||
if child.margin_top == 'auto':
|
||
child.margin_top = free_space
|
||
if child.margin_bottom == 'auto':
|
||
child.margin_bottom = free_space
|
||
free_space = 0
|
||
|
||
if box.style['direction'] == 'rtl' and main == 'width':
|
||
free_space *= -1
|
||
|
||
# 12.2 Align the items along the main-axis per justify-content.
|
||
if {'end', 'flex-end', 'right'} & set(justify_content):
|
||
position_main += free_space
|
||
elif 'center' in justify_content:
|
||
position_main += free_space / 2
|
||
elif 'space-around' in justify_content:
|
||
position_main += free_space / len(line) / 2
|
||
elif 'space-evenly' in justify_content:
|
||
position_main += free_space / (len(line) + 1)
|
||
|
||
growths = sum(child.style['flex_grow'] for child in children)
|
||
for i, (index, child) in enumerate(line):
|
||
if i:
|
||
position_main += main_gap
|
||
if main == 'width':
|
||
child.position_x = position_main
|
||
if 'stretch' in justify_content and growths:
|
||
child.width += free_space * child.style['flex_grow'] / growths
|
||
else:
|
||
child.position_y = position_main
|
||
margin_main = (
|
||
child.margin_width() if main == 'width' else child.margin_height())
|
||
if box.style['direction'] == 'rtl' and main == 'width':
|
||
margin_main *= -1
|
||
position_main += margin_main
|
||
if 'space-around' in justify_content:
|
||
position_main += free_space / len(line)
|
||
elif 'space-between' in justify_content:
|
||
if len(line) > 1:
|
||
position_main += free_space / (len(line) - 1)
|
||
elif 'space-evenly' in justify_content:
|
||
position_main += free_space / (len(line) + 1)
|
||
|
||
# 13 Resolve cross-axis auto margins.
|
||
if cross == 'width':
|
||
# Make sure width/margins are no longer "auto", as we did not do it above in
|
||
# step 4.
|
||
block.block_level_width(box, containing_block)
|
||
position_cross = box.content_box_y() if cross == 'height' else box.content_box_x()
|
||
for line in flex_lines:
|
||
line.lower_baseline = -inf
|
||
# TODO: Don't duplicate this loop.
|
||
for index, child in line:
|
||
align_self = child.style['align_self']
|
||
if 'auto' in align_self:
|
||
align_self = align_items
|
||
if 'baseline' in align_self and main == 'width':
|
||
# TODO: handle vertical text.
|
||
child.baseline = child._baseline - position_cross
|
||
line.lower_baseline = max(line.lower_baseline, child.baseline)
|
||
if line.lower_baseline == -inf:
|
||
line.lower_baseline = line[0][1]._baseline if line else 0
|
||
for index, child in line:
|
||
cross_margins = (
|
||
(child.style['margin_top'], child.style['margin_bottom'])
|
||
if cross == 'height' else
|
||
(child.style['margin_left'], child.style['margin_right']))
|
||
auto_margins = sum([margin == 'auto' for margin in cross_margins])
|
||
# If a flex item has auto cross-axis margins…
|
||
if auto_margins:
|
||
extra_cross = line.cross_size
|
||
if cross == 'height':
|
||
extra_cross -= child.border_height()
|
||
if child.margin_top != 'auto':
|
||
extra_cross -= child.margin_top
|
||
if child.margin_bottom != 'auto':
|
||
extra_cross -= child.margin_bottom
|
||
else:
|
||
extra_cross -= child.border_width()
|
||
if child.margin_left != 'auto':
|
||
extra_cross -= child.margin_left
|
||
if child.margin_right != 'auto':
|
||
extra_cross -= child.margin_right
|
||
if extra_cross > 0:
|
||
# If its outer cross size is less than the cross size…
|
||
extra_cross /= auto_margins
|
||
if cross == 'height':
|
||
if child.style['margin_top'] == 'auto':
|
||
child.margin_top = extra_cross
|
||
if child.style['margin_bottom'] == 'auto':
|
||
child.margin_bottom = extra_cross
|
||
else:
|
||
if child.style['margin_left'] == 'auto':
|
||
child.margin_left = extra_cross
|
||
if child.style['margin_right'] == 'auto':
|
||
child.margin_right = extra_cross
|
||
else:
|
||
# Otherwise…
|
||
if cross == 'height':
|
||
if child.margin_top == 'auto':
|
||
child.margin_top = 0
|
||
child.margin_bottom = extra_cross
|
||
else:
|
||
if child.margin_left == 'auto':
|
||
child.margin_left = 0
|
||
child.margin_right = extra_cross
|
||
else:
|
||
# 14 Align all flex items along the cross-axis.
|
||
align_self = child.style['align_self']
|
||
if 'normal' in align_self:
|
||
align_self = ('stretch',)
|
||
elif 'auto' in align_self:
|
||
align_self = align_items
|
||
position = 'position_y' if cross == 'height' else 'position_x'
|
||
setattr(child, position, position_cross)
|
||
if {'end', 'self-end', 'flex-end'} & set(align_self):
|
||
if cross == 'height':
|
||
child.position_y += line.cross_size - child.margin_height()
|
||
else:
|
||
child.position_x += line.cross_size - child.margin_width()
|
||
elif 'center' in align_self:
|
||
if cross == 'height':
|
||
child.position_y += (
|
||
line.cross_size - child.margin_height()) / 2
|
||
else:
|
||
child.position_x += (line.cross_size - child.margin_width()) / 2
|
||
elif 'baseline' in align_self:
|
||
if cross == 'height':
|
||
child.position_y += line.lower_baseline - child.baseline
|
||
else:
|
||
# TODO: Handle vertical text.
|
||
pass
|
||
elif 'stretch' in align_self:
|
||
if child.style[cross] == 'auto':
|
||
if cross == 'height':
|
||
margins = child.margin_top + child.margin_bottom
|
||
else:
|
||
margins = child.margin_left + child.margin_right
|
||
if child.style['box_sizing'] == 'content-box':
|
||
if cross == 'height':
|
||
margins += (
|
||
child.border_top_width + child.border_bottom_width +
|
||
child.padding_top + child.padding_bottom)
|
||
else:
|
||
margins += (
|
||
child.border_left_width + child.border_right_width +
|
||
child.padding_left + child.padding_right)
|
||
position_cross += line.cross_size
|
||
|
||
# 15 Determine the flex container’s used cross size.
|
||
# TODO: Use the updated algorithm.
|
||
if getattr(box, cross) == 'auto':
|
||
# Otherwise, use the sum of the flex lines' cross sizes…
|
||
# TODO: Handle min-max.
|
||
# TODO: What about align-content here?
|
||
cross_size = sum(line.cross_size for line in flex_lines)
|
||
cross_size += (len(flex_lines) - 1) * cross_gap
|
||
setattr(box, cross, cross_size)
|
||
|
||
if len(flex_lines) > 1:
|
||
# 15 If the cross size property is a definite size, use that…
|
||
extra_cross_size = getattr(box, cross)
|
||
extra_cross_size -= sum(line.cross_size for line in flex_lines)
|
||
extra_cross_size -= (len(flex_lines) - 1) * cross_gap
|
||
# 16 Align all flex lines per align-content.
|
||
cross_translate = 0
|
||
direction = 'position_y' if cross == 'height' else 'position_x'
|
||
for i, line in enumerate(flex_lines):
|
||
flex_items = tuple(child for _, child in line if child.is_flex_item)
|
||
if i:
|
||
cross_translate += cross_gap
|
||
for child in flex_items:
|
||
current_value = getattr(child, direction) + cross_translate
|
||
setattr(child, direction, current_value)
|
||
if extra_cross_size == 0:
|
||
continue
|
||
for child in flex_items:
|
||
if {'flex-end', 'end'} & set(align_content):
|
||
setattr(child, direction, current_value + extra_cross_size)
|
||
elif 'center' in align_content:
|
||
setattr(child, direction, current_value + extra_cross_size / 2)
|
||
elif 'space-around' in align_content:
|
||
setattr(
|
||
child, direction,
|
||
current_value + extra_cross_size / len(flex_lines) / 2)
|
||
elif 'space-evenly' in align_content:
|
||
setattr(
|
||
child, direction,
|
||
current_value + extra_cross_size / (len(flex_lines) + 1))
|
||
if 'space-between' in align_content:
|
||
cross_translate += extra_cross_size / (len(flex_lines) - 1)
|
||
elif 'space-around' in align_content:
|
||
cross_translate += extra_cross_size / len(flex_lines)
|
||
elif 'space-evenly' in align_content:
|
||
cross_translate += extra_cross_size / (len(flex_lines) + 1)
|
||
|
||
# Now we are no longer in the flex algorithm.
|
||
box = box.copy_with_children(
|
||
[child for child in children if child.is_absolutely_positioned()])
|
||
child_skip_stack = skip_stack
|
||
for line in flex_lines:
|
||
for index, child in line:
|
||
if child.is_flex_item:
|
||
# TODO: Don't use block_level_layout_switch.
|
||
new_child, child_resume_at = block.block_level_layout_switch(
|
||
context, child, bottom_space, child_skip_stack, box, page_is_empty,
|
||
absolute_boxes, fixed_boxes, adjoining_margins=[], discard=discard,
|
||
max_lines=None)[:2]
|
||
if new_child is None:
|
||
if resume_at:
|
||
resume_index, = resume_at
|
||
resume_index -= 1
|
||
else:
|
||
resume_index = 0
|
||
resume_at = {resume_index + index: None}
|
||
else:
|
||
page_is_empty = False
|
||
box.children.append(new_child)
|
||
if child_resume_at is not None:
|
||
if original_skip_stack:
|
||
first_level_skip, = original_skip_stack
|
||
else:
|
||
first_level_skip = 0
|
||
if resume_at:
|
||
resume_index, = resume_at
|
||
first_level_skip += resume_index
|
||
resume_at = {first_level_skip + index: child_resume_at}
|
||
if resume_at:
|
||
break
|
||
|
||
# Skip stack is only for the first child.
|
||
child_skip_stack = None
|
||
if resume_at:
|
||
break
|
||
|
||
if box.style['position'] == 'relative':
|
||
# New containing block, resolve the layout of the absolute descendants.
|
||
for absolute_box in absolute_boxes:
|
||
absolute_layout(
|
||
context, absolute_box, box, fixed_boxes, bottom_space, skip_stack=None)
|
||
|
||
# TODO: Use real algorithm, see https://www.w3.org/TR/css-flexbox-1/#flex-baselines.
|
||
if isinstance(box, boxes.InlineFlexBox):
|
||
if main == 'width': # and main text direction is horizontal
|
||
box.baseline = flex_lines[0].lower_baseline if flex_lines else 0
|
||
else:
|
||
for child in box.children:
|
||
if child.is_in_normal_flow():
|
||
box.baseline = find_in_flow_baseline(child) or 0
|
||
break
|
||
else:
|
||
box.baseline = 0
|
||
|
||
box.remove_decoration(start=False, end=resume_at and not discard)
|
||
|
||
context.finish_flex_formatting_context(box)
|
||
|
||
# TODO: Check these returned values.
|
||
return box, resume_at, {'break': 'any', 'page': None}, [], False
|