ladybird/Userland/Libraries/LibWeb/LayoutTreeModel.cpp

/*
 * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include "LayoutTreeModel.h"
#include <AK/StringBuilder.h>
#include <LibWeb/DOM/Document.h>
#include <LibWeb/DOM/Element.h>
#include <LibWeb/Layout/InitialContainingBlockBox.h>
#include <LibWeb/Layout/TextNode.h>
#include <ctype.h>
#include <stdio.h>

namespace Web {

LayoutTreeModel::LayoutTreeModel(DOM::Document& document)
    : m_document(document)
{
    m_document_icon.set_bitmap_for_size(16, Gfx::Bitmap::try_load_from_file("/res/icons/16x16/filetype-html.png"));
    m_element_icon.set_bitmap_for_size(16, Gfx::Bitmap::try_load_from_file("/res/icons/16x16/inspector-object.png"));
    m_text_icon.set_bitmap_for_size(16, Gfx::Bitmap::try_load_from_file("/res/icons/16x16/filetype-unknown.png"));
}

LayoutTreeModel::~LayoutTreeModel()
{
}

GUI::ModelIndex LayoutTreeModel::index(int row, int column, const GUI::ModelIndex& parent) const
{
    if (!parent.is_valid())
        return create_index(row, column, m_document->layout_node());
    auto& parent_node = *static_cast<Layout::Node*>(parent.internal_data());
    return create_index(row, column, parent_node.child_at_index(row));
}

GUI::ModelIndex LayoutTreeModel::parent_index(const GUI::ModelIndex& index) const
{
    if (!index.is_valid())
        return {};
    auto& node = *static_cast<Layout::Node*>(index.internal_data());
    if (!node.parent())
        return {};

    // No grandparent? Parent is the document!
    if (!node.parent()->parent()) {
        return create_index(0, 0, m_document->layout_node());
    }

    // Walk the grandparent's children to find the index of node's parent in its parent.
    // (This is needed to produce the row number of the GUI::ModelIndex corresponding to node's parent.)
    int grandparent_child_index = 0;
    for (auto* grandparent_child = node.parent()->parent()->first_child(); grandparent_child; grandparent_child = grandparent_child->next_sibling()) {
        if (grandparent_child == node.parent())
            return create_index(grandparent_child_index, 0, node.parent());
        ++grandparent_child_index;
    }

    VERIFY_NOT_REACHED();
    return {};
}

int LayoutTreeModel::row_count(const GUI::ModelIndex& index) const
{
    if (!index.is_valid())
        return 1;
    auto& node = *static_cast<Layout::Node*>(index.internal_data());
    return node.child_count();
}

int LayoutTreeModel::column_count(const GUI::ModelIndex&) const
{
    return 1;
}

static String with_whitespace_collapsed(const StringView& string)
{
    StringBuilder builder;
    for (size_t i = 0; i < string.length(); ++i) {
        if (isspace(string[i])) {
            builder.append(' ');
            while (i < string.length()) {
                if (isspace(string[i])) {
                    ++i;
                    continue;
                }
                builder.append(string[i]);
                break;
            }
            continue;
        }
        builder.append(string[i]);
    }
    return builder.to_string();
}

GUI::Variant LayoutTreeModel::data(const GUI::ModelIndex& index, GUI::ModelRole role) const
{
    auto& node = *static_cast<Layout::Node*>(index.internal_data());
    if (role == GUI::ModelRole::Icon) {
        if (is<Layout::InitialContainingBlockBox>(node))
            return m_document_icon;
        if (is<Layout::TextNode>(node))
            return m_text_icon;
        return m_element_icon;
    }
    if (role == GUI::ModelRole::Display) {
        if (is<Layout::TextNode>(node))
            return String::formatted("TextNode: {}", with_whitespace_collapsed(verify_cast<Layout::TextNode>(node).text_for_rendering()));
        StringBuilder builder;
        builder.append(node.class_name());
        builder.append(' ');
        if (node.is_anonymous()) {
            builder.append("[anonymous]");
        } else if (!node.dom_node()->is_element()) {
            builder.append(node.dom_node()->node_name());
        } else {
            auto& element = verify_cast<DOM::Element>(*node.dom_node());
            builder.append('<');
            builder.append(element.local_name());
            element.for_each_attribute([&](auto& name, auto& value) {
                builder.append(' ');
                builder.append(name);
                builder.append('=');
                builder.append('"');
                builder.append(value);
                builder.append('"');
            });
            builder.append('>');
        }
        return builder.to_string();
    }
    return {};
}

}