| /* |
| * Copyright (C) 2018 Apple Inc. 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 APPLE INC. ``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 APPLE INC. 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. |
| */ |
| |
| /* |
| class FormattingContext { |
| public: |
| Layout::Container& formattingRoot(); |
| FormattingState& formattingState(); |
| LayoutState& layoutState(); |
| FloatingContext& floatingContext(); |
| |
| virtual void layout(); |
| |
| virtual void computeWidth(const Layout::Box&); |
| virtual void computeHeight(const Layout::Box&); |
| |
| virtual LayoutUnit marginTop(const Layout::Box&); |
| virtual LayoutUnit marginLeft(const Layout::Box&); |
| virtual LayoutUnit marginBottom(const Layout::Box&); |
| virtual LayoutUnit marginRight(const Layout::Box&); |
| |
| private: |
| void computeFloatingWidth(const Layout::Box&); |
| void computeFloatingHeight(const Layout::Box&); |
| |
| void placeInFlowPositionedChildren(const Layout::Box&); |
| void computeInFlowPositionedPosition(const Layout::Box&); |
| void computeInFlowWidth(const Layout::Box&); |
| |
| void layoutOutOfFlowDescendants(); |
| |
| void computeOutOfFlowWidth(const Layout::Box&); |
| void computeOutOfFlowHeight(const Layout::Box&); |
| void computeOutOfFlowPosition(const Layout::Box&); |
| |
| LayoutUnit shrinkToFitWidth(Layout::Box&); |
| }; |
| */ |
| class FormattingContext { |
| constructor(formattingState) { |
| this.m_formattingState = formattingState; |
| this.m_floatingContext = new FloatingContext(formattingState.floatingState()); |
| this.m_layoutStack = new Array(); |
| } |
| |
| formattingRoot() { |
| return this.m_formattingState.formattingRoot(); |
| } |
| |
| formattingState() { |
| return this.m_formattingState; |
| } |
| |
| layoutState() { |
| return this.formattingState().layoutState(); |
| } |
| |
| floatingContext() { |
| return this.m_floatingContext; |
| } |
| |
| layout() { |
| ASSERT_NOT_REACHED(); |
| } |
| |
| computeWidth(layoutBox) { |
| } |
| |
| computeHeight(layoutBox) { |
| } |
| |
| marginTop(layoutBox) { |
| return Utils.computedMarginTop(layoutBox.node()); |
| } |
| |
| marginLeft(layoutBox) { |
| return Utils.computedMarginLeft(layoutBox.node()); |
| } |
| |
| marginBottom(layoutBox) { |
| return Utils.computedMarginBottom(layoutBox.node()); |
| } |
| |
| marginRight(layoutBox) { |
| return Utils.computedMarginRight(layoutBox.node()); |
| } |
| |
| static isInFormattingContext(layoutBox, formattingContextRoot) { |
| ASSERT(formattingContextRoot.establishesFormattingContext()); |
| // If we hit the "this" while climbing up on the containing block chain and we don't pass a formatting context root -> box is part of this box's formatting context. |
| for (let containingBlock = layoutBox.containingBlock(); containingBlock; containingBlock = containingBlock.containingBlock()) { |
| if (containingBlock == formattingContextRoot) |
| return true; |
| if (containingBlock.establishesFormattingContext()) |
| return false; |
| } |
| return false; |
| } |
| |
| _descendantNeedsLayout() { |
| return this.m_layoutStack.length; |
| } |
| |
| _addToLayoutQueue(layoutBox) { |
| if (!layoutBox) |
| return; |
| // Initialize the corresponding display box. |
| let displayBox = this.formattingState().createDisplayBox(layoutBox, this); |
| if (layoutBox.node()) { |
| displayBox.setMarginTop(this.marginTop(layoutBox)); |
| displayBox.setMarginLeft(this.marginLeft(layoutBox)); |
| displayBox.setMarginBottom(this.marginBottom(layoutBox)); |
| displayBox.setMarginRight(this.marginRight(layoutBox)); |
| } |
| |
| this.m_layoutStack.push(layoutBox); |
| } |
| |
| _nextInLayoutQueue() { |
| ASSERT(this.m_layoutStack.length); |
| return this.m_layoutStack[this.m_layoutStack.length - 1]; |
| } |
| |
| _removeFromLayoutQueue(layoutBox) { |
| // With the current layout logic, the layoutBox should be at the top (this.m_layoutStack.pop() should do). |
| ASSERT(this.m_layoutStack.length); |
| ASSERT(this.m_layoutStack[this.m_layoutStack.length - 1] == layoutBox); |
| this.m_layoutStack.splice(this.m_layoutStack.indexOf(layoutBox), 1); |
| } |
| |
| displayBox(layoutBox) { |
| return this.formattingState().displayBox(layoutBox); |
| } |
| |
| _computeFloatingWidth(layoutBox) { |
| // FIXME: missing cases |
| this.displayBox(layoutBox).setWidth(Utils.width(layoutBox) + Utils.computedHorizontalBorderAndPadding(layoutBox.node())); |
| } |
| |
| _computeFloatingHeight(layoutBox) { |
| // FIXME: missing cases |
| this.displayBox(layoutBox).setHeight(Utils.height(layoutBox) + Utils.computedVerticalBorderAndPadding(layoutBox.node())); |
| } |
| |
| _placeInFlowPositionedChildren(container) { |
| if (!container.isContainer()) |
| return; |
| // If this layoutBox also establishes a formatting context, then positioning already has happend at the formatting context. |
| if (container.establishesFormattingContext() && container != this.formattingRoot()) |
| return; |
| ASSERT(container.isContainer()); |
| for (let inFlowChild = container.firstInFlowChild(); inFlowChild; inFlowChild = inFlowChild.nextInFlowSibling()) { |
| if (!inFlowChild.isInFlowPositioned()) |
| continue; |
| this._computeInFlowPositionedPosition(inFlowChild); |
| } |
| } |
| |
| _computeInFlowPositionedPosition(layoutBox) { |
| // Start with the original, static position. |
| let displayBox = this.displayBox(layoutBox); |
| let relativePosition = displayBox.topLeft(); |
| // Top/bottom |
| if (!Utils.isTopAuto(layoutBox)) |
| relativePosition.shiftTop(Utils.top(layoutBox)); |
| else if (!Utils.isBottomAuto(layoutBox)) |
| relativePosition.shiftTop(-Utils.bottom(layoutBox)); |
| // Left/right |
| if (!Utils.isLeftAuto(layoutBox)) |
| relativePosition.shiftLeft(Utils.left(layoutBox)); |
| else if (!Utils.isRightAuto(layoutBox)) |
| relativePosition.shiftLeft(-Utils.right(layoutBox)); |
| displayBox.setTopLeft(relativePosition); |
| } |
| |
| _computeInFlowWidth(layoutBox) { |
| if (Utils.isWidthAuto(layoutBox)) |
| return this.displayBox(layoutBox).setWidth(this._horizontalConstraint(layoutBox)); |
| return this.displayBox(layoutBox).setWidth(Utils.width(layoutBox) + Utils.computedHorizontalBorderAndPadding(layoutBox.node())); |
| } |
| |
| _layoutOutOfFlowDescendants() { |
| // This lays out all the out-of-flow boxes that belong to this formatting context even if |
| // the root container is not the containing block. |
| let outOfFlowDescendants = this._outOfFlowDescendants(); |
| for (let outOfFlowBox of outOfFlowDescendants) { |
| this._addToLayoutQueue(outOfFlowBox); |
| this._computeOutOfFlowWidth(outOfFlowBox); |
| this.layoutState().formattingContext(outOfFlowBox).layout(); |
| this._computeOutOfFlowHeight(outOfFlowBox); |
| this._computeOutOfFlowPosition(outOfFlowBox); |
| this._removeFromLayoutQueue(outOfFlowBox); |
| this.formattingState().clearNeedsLayout(outOfFlowBox); |
| } |
| } |
| |
| _computeOutOfFlowWidth(layoutBox) { |
| // 10.3.7 Absolutely positioned, non-replaced elements |
| |
| // 1. 'left' and 'width' are 'auto' and 'right' is not 'auto', then the width is shrink-to-fit. Then solve for 'left' |
| // 2. 'left' and 'right' are 'auto' and 'width' is not 'auto', then if the 'direction' property of the element establishing |
| // the static-position containing block is 'ltr' set 'left' to the static position, otherwise set 'right' to the static position. |
| // Then solve for 'left' (if 'direction is 'rtl') or 'right' (if 'direction' is 'ltr'). |
| // 3. 'width' and 'right' are 'auto' and 'left' is not 'auto', then the width is shrink-to-fit . Then solve for 'right' |
| // 4. 'left' is 'auto', 'width' and 'right' are not 'auto', then solve for 'left' |
| // 5. 'width' is 'auto', 'left' and 'right' are not 'auto', then solve for 'width' |
| // 6. 'right' is 'auto', 'left' and 'width' are not 'auto', then solve for 'right' |
| let width = Number.NaN; |
| if (Utils.isWidthAuto(layoutBox) && Utils.isLeftAuto(layoutBox) && Utils.isRightAuto(layoutBox)) |
| width = this._shrinkToFitWidth(layoutBox); |
| else if (Utils.isLeftAuto(layoutBox) && Utils.isWidthAuto(layoutBox) && !Utils.isRightAuto(layoutBox)) |
| width = this._shrinkToFitWidth(layoutBox); // 1 |
| else if (Utils.isLeftAuto(layoutBox) && Utils.isRightAuto(layoutBox) && !Utils.isWidthAuto(layoutBox)) |
| width = Utils.width(layoutBox); // 2 |
| else if (Utils.isWidthAuto(layoutBox) && Utils.isRightAuto(layoutBox) && !Utils.isLeftAuto(layoutBox)) |
| width = this._shrinkToFitWidth(layoutBox); // 3 |
| else if (Utils.isLeftAuto(layoutBox) && !Utils.isWidthAuto(layoutBox) && !Utils.isRightAuto(layoutBox)) |
| width = Utils.width(layoutBox); // 4 |
| else if (Utils.isWidthAuto(layoutBox) && !Utils.isLeftAuto(layoutBox) && !Utils.isRightAuto(layoutBox)) |
| width = Math.max(0, this.displayBox(layoutBox.containingBlock()).contentBox().width() - Utils.right(layoutBox) - Utils.left(layoutBox)); // 5 |
| else if (Utils.isRightAuto(layoutBox) && !Utils.isLeftAuto(layoutBox) && !Utils.isWidthAuto(layoutBox)) |
| width = Utils.width(layoutBox); // 6 |
| else |
| ASSERT_NOT_REACHED(); |
| width += Utils.computedHorizontalBorderAndPadding(layoutBox.node()); |
| this.displayBox(layoutBox).setWidth(width); |
| } |
| |
| _computeOutOfFlowHeight(layoutBox) { |
| // 1. If all three of 'top', 'height', and 'bottom' are auto, set 'top' to the static position and apply rule number three below. |
| // 2. If none of the three are 'auto': If both 'margin-top' and 'margin-bottom' are 'auto', solve the equation under |
| // the extra constraint that the two margins get equal values. If one of 'margin-top' or 'margin-bottom' is 'auto', |
| // solve the equation for that value. If the values are over-constrained, ignore the value for 'bottom' and solve for that value. |
| // Otherwise, pick the one of the following six rules that applies. |
| |
| // 3. 'top' and 'height' are 'auto' and 'bottom' is not 'auto', then the height is based on the content per 10.6.7, |
| // set 'auto' values for 'margin-top' and 'margin-bottom' to 0, and solve for 'top' |
| // 4. 'top' and 'bottom' are 'auto' and 'height' is not 'auto', then set 'top' to the static position, set 'auto' values |
| // for 'margin-top' and 'margin-bottom' to 0, and solve for 'bottom' |
| // 5. 'height' and 'bottom' are 'auto' and 'top' is not 'auto', then the height is based on the content per 10.6.7, |
| // set 'auto' values for 'margin-top' and 'margin-bottom' to 0, and solve for 'bottom' |
| // 6. 'top' is 'auto', 'height' and 'bottom' are not 'auto', then set 'auto' values for 'margin-top' and 'margin-bottom' to 0, and solve for 'top' |
| // 7. 'height' is 'auto', 'top' and 'bottom' are not 'auto', then 'auto' values for 'margin-top' and 'margin-bottom' are set to 0 and solve for 'height' |
| // 8. 'bottom' is 'auto', 'top' and 'height' are not 'auto', then set 'auto' values for 'margin-top' and 'margin-bottom' to 0 and solve for 'bottom' |
| let height = Number.NaN; |
| if (Utils.isHeightAuto(layoutBox) && Utils.isBottomAuto(layoutBox) && Utils.isTopAuto(layoutBox)) |
| height = this._contentHeight(layoutBox); // 1 |
| else if (Utils.isTopAuto((layoutBox)) && Utils.isHeightAuto((layoutBox)) && !Utils.isBottomAuto((layoutBox))) |
| height = this._contentHeight(layoutBox); // 3 |
| else if (Utils.isTopAuto((layoutBox)) && Utils.isBottomAuto((layoutBox)) && !Utils.isHeightAuto((layoutBox))) |
| height = Utils.height(layoutBox); // 4 |
| else if (Utils.isHeightAuto((layoutBox)) && Utils.isBottomAuto((layoutBox)) && !Utils.isTopAuto((layoutBox))) |
| height = this._contentHeight(layoutBox); // 5 |
| else if (Utils.isTopAuto((layoutBox)) && !Utils.isHeightAuto((layoutBox)) && !Utils.isBottomAuto((layoutBox))) |
| height = Utils.height(layoutBox); // 6 |
| else if (Utils.isHeightAuto((layoutBox)) && !Utils.isTopAuto((layoutBox)) && !Utils.isBottomAuto((layoutBox))) |
| height = Math.max(0, this.displayBox(layoutBox.containingBlock()).contentBox().height() - Utils.bottom(layoutBox) - Utils.top(layoutBox)); // 7 |
| else if (Utils.isBottomAuto((layoutBox)) && !Utils.isTopAuto((layoutBox)) && !Utils.isHeightAuto((layoutBox))) |
| height = Utils.height(layoutBox); // 8 |
| else |
| ASSERT_NOT_REACHED(); |
| height += Utils.computedVerticalBorderAndPadding(layoutBox.node()); |
| this.displayBox(layoutBox).setHeight(height); |
| } |
| |
| _computeOutOfFlowPosition(layoutBox) { |
| let displayBox = this.displayBox(layoutBox); |
| let top = Number.NaN; |
| let containerSize = this.displayBox(layoutBox.containingBlock()).contentBox().size(); |
| // Top/bottom |
| if (Utils.isTopAuto(layoutBox) && Utils.isBottomAuto(layoutBox)) { |
| ASSERT(Utils.isStaticallyPositioned(layoutBox)); |
| // Vertically statically positioned. |
| // FIXME: Figure out if it is actually valid that we use the parent box as the container (which is not even in this formatting context). |
| let parent = layoutBox.parent(); |
| let parentDisplayBox = this.displayBox(parent); |
| let previousInFlowSibling = layoutBox.previousInFlowSibling(); |
| let contentBottom = previousInFlowSibling ? this.displayBox(previousInFlowSibling).bottom() : parentDisplayBox.contentBox().top(); |
| top = contentBottom + this.marginTop(layoutBox); |
| // Convert static position (in parent coordinate system) to absolute (in containing block coordindate system). |
| if (parent != layoutBox.containingBlock()) { |
| ASSERT(displayBox.parent() == this.displayBox(layoutBox.containingBlock())); |
| top += Utils.mapPosition(parentDisplayBox.topLeft(), parentDisplayBox, displayBox.parent()).top(); |
| } |
| } else if (!Utils.isTopAuto(layoutBox)) |
| top = Utils.top(layoutBox) + this.marginTop(layoutBox); |
| else if (!Utils.isBottomAuto(layoutBox)) |
| top = containerSize.height() - Utils.bottom(layoutBox) - displayBox.height() - this.marginBottom(layoutBox); |
| else |
| ASSERT_NOT_REACHED(); |
| // Left/right |
| let left = Number.NaN; |
| if (Utils.isLeftAuto(layoutBox) && Utils.isRightAuto(layoutBox)) { |
| ASSERT(Utils.isStaticallyPositioned(layoutBox)); |
| // Horizontally statically positioned. |
| // FIXME: Figure out if it is actually valid that we use the parent box as the container (which is not even in this formatting context). |
| let parent = layoutBox.parent(); |
| let parentDisplayBox = this.displayBox(parent); |
| left = parentDisplayBox.contentBox().left() + this.marginLeft(layoutBox); |
| // Convert static position (in parent coordinate system) to absolute (in containing block coordindate system). |
| if (parent != layoutBox.containingBlock()) { |
| ASSERT(displayBox.parent() == this.displayBox(layoutBox.containingBlock())); |
| left += Utils.mapPosition(parentDisplayBox.topLeft(), parentDisplayBox, displayBox.parent()).left(); |
| } |
| } else if (!Utils.isLeftAuto(layoutBox)) |
| left = Utils.left(layoutBox) + this.marginLeft(layoutBox); |
| else if (!Utils.isRightAuto(layoutBox)) |
| left = containerSize.width() - Utils.right(layoutBox) - displayBox.width() - this.marginRight(layoutBox); |
| else |
| ASSERT_NOT_REACHED(); |
| displayBox.setTopLeft(new LayoutPoint(top, left)); |
| } |
| |
| _shrinkToFitWidth(layoutBox) { |
| // FIXME: this is naive and missing the actual preferred width computation. |
| ASSERT(Utils.isWidthAuto(layoutBox)); |
| if (!layoutBox.isContainer() || !layoutBox.hasChild()) |
| return 0; |
| let width = 0; |
| for (let inFlowChild = layoutBox.firstInFlowChild(); inFlowChild; inFlowChild = inFlowChild.nextInFlowSibling()) { |
| let widthCandidate = Utils.isWidthAuto(inFlowChild) ? this._shrinkToFitWidth(inFlowChild) : Utils.width(inFlowChild); |
| width = Math.max(width, widthCandidate + Utils.computedHorizontalBorderAndPadding(inFlowChild.node())); |
| } |
| return width; |
| } |
| |
| _outOfFlowDescendants() { |
| // FIXME: This is highly inefficient but will do for now. |
| // 1. Collect all the out-of-flow descendants first. |
| // 2. Check if they are all belong to this formatting context. |
| // - either the root container is the containing block. |
| // - or a descendant of the root container is the containing block |
| // and there is not other formatting context inbetween. |
| let allOutOfFlowBoxes = new Array(); |
| let descendants = new Array(); |
| for (let child = this.formattingRoot().firstChild(); child; child = child.nextSibling()) |
| descendants.push(child); |
| while (descendants.length) { |
| let descendant = descendants.pop(); |
| if (descendant.isOutOfFlowPositioned()) |
| allOutOfFlowBoxes.push(descendant); |
| if (!descendant.isContainer()) |
| continue; |
| for (let child = descendant.lastChild(); child; child = child.previousSibling()) |
| descendants.push(child); |
| } |
| let outOfFlowBoxes = new Array(); |
| for (let outOfFlowBox of allOutOfFlowBoxes) { |
| let containingBlock = outOfFlowBox.containingBlock(); |
| // Collect the out-of-flow descendant that belong to this formatting context. |
| if (containingBlock == this.formattingRoot()) |
| outOfFlowBoxes.push(outOfFlowBox); |
| else if (containingBlock.isDescendantOf(this.formattingRoot())) { |
| if (!containingBlock.establishesFormattingContext() || !containingBlock.isPositioned()) |
| outOfFlowBoxes.push(outOfFlowBox); |
| } |
| } |
| return outOfFlowBoxes; |
| } |
| |
| _firstInFlowChildWithNeedsLayout(layoutBox) { |
| if (!layoutBox.isContainer()) |
| return null; |
| for (let child = layoutBox.firstInFlowOrFloatChild(); child; child = child.nextInFlowOrFloatSibling()) { |
| if (this.formattingState().needsLayout(child)) |
| return child; |
| } |
| return null; |
| } |
| |
| _nextInFlowSiblingWithNeedsLayout(layoutBox) { |
| for (let sibling = layoutBox.nextInFlowOrFloatSibling(); sibling; sibling = sibling.nextInFlowOrFloatSibling()) { |
| if (this.formattingState().needsLayout(sibling)) |
| return sibling; |
| } |
| return null; |
| } |
| } |
