Tools/LayoutReloaded/FormattingState/FormattingState.js

/*
 * 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
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 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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class FormattingState {
    constructor(layoutState, formattingRoot) {
        this.m_layoutState = layoutState;
        this.m_formattingContext = null;
        this.m_formattingRoot = formattingRoot;
        this.m_displayToLayout = new Map();
    }

    formattingContext() {
        return this.m_formattingContext;
    }

    formattingRoot() {
        return this.m_formattingRoot;
    }

    layoutState() {
        return this.m_layoutState;
    }

    createDisplayBox(layoutBox) {
        let displayBox = new Display.Box(layoutBox.node());
        this.m_displayToLayout.set(layoutBox, displayBox);
    }

    displayBoxMap() {
        return this.m_displayToLayout;
    }

    displayBox(layoutBox) {
        ASSERT(layoutBox);
        // 1. Normally we only need to access boxes within the same formatting context
        // 2. In some cases we need size information about the root container -which is in the parent formatting context
        // 3. In rare cases (statically positioned out-of-flow box), we need position information on sibling formatting context
        // but in all cases it needs to be a descendant of the root container (or the container itself)
        ASSERT(layoutBox == this.formattingRoot() || layoutBox.isDescendantOf(this.formattingRoot()));
        let displayBox = this.m_displayToLayout.get(layoutBox);
        if (displayBox)
            return displayBox;

        let formattingStates = this.layoutState().formattingStates();
        for (let formattingState of formattingStates) {
            let displayBox = formattingState[1].displayBoxMap().get(layoutBox);
            if (displayBox)
                return displayBox;
        }
        // It must be the ICB.
        ASSERT(!layoutBox.parent());
        return this.layoutState().initialDisplayBox();
    }

    _setFormattingContext(formattingContext) {
        this.m_formattingContext = formattingContext;
    }
}