wisemapping-frontend/packages/mindplot/lib/components/layout/BalancedSorter.js

/*
 *    Copyright [2015] [wisemapping]
 *
 *   Licensed under WiseMapping Public License, Version 1.0 (the "License").
 *   It is basically the Apache License, Version 2.0 (the "License") plus the
 *   "powered by wisemapping" text requirement on every single page;
 *   you may not use this file except in compliance with the License.
 *   You may obtain a copy of the license at
 *
 *       http://www.wisemapping.org/license
 *
 *   Unless required by applicable law or agreed to in writing, software
 *   distributed under the License is distributed on an "AS IS" BASIS,
 *   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *   See the License for the specific language governing permissions and
 *   limitations under the License.
 */
const AbstractBasicSorter = require('./AbstractBasicSorter').default;

const BalancedSorter = new Class(
    /** @lends BalancedSorter */ {
        Extends: AbstractBasicSorter,
        /**
         * @constructs
         * @extends mindplot.layout.AbstractBasicSorter
         */
        initialize: function () {},

        /**
         * @param {} graph
         * @param {} parent
         * @param {} node
         * @param {} position
         * @param {Boolean} free
         * @return an array with order and position
         */
        predict: function (graph, parent, node, position, free) {
            // If its a free node...
            if (free) {
                $assert(
                    $defined(position),
                    'position cannot be null for predict in free positioning'
                );
                $assert($defined(node), 'node cannot be null for predict in free positioning');

                var rootNode = graph.getRootNode(parent);
                var direction = this._getRelativeDirection(
                    rootNode.getPosition(),
                    node.getPosition()
                );

                var limitXPos =
                    parent.getPosition().x +
                    direction *
                        (parent.getSize().width / 2 +
                            node.getSize().width / 2 +
                            BalancedSorter.INTERNODE_HORIZONTAL_PADDING);

                var xPos =
                    direction > 0
                        ? position.x >= limitXPos
                            ? position.x
                            : limitXPos
                        : position.x <= limitXPos
                        ? position.x
                        : limitXPos;

                return [0, { x: xPos, y: position.y }];
            }

            var rootNode = graph.getRootNode(parent);

            // If it is a dragged node...
            if (node) {
                $assert($defined(position), 'position cannot be null for predict in dragging');
                var nodeDirection = this._getRelativeDirection(
                    rootNode.getPosition(),
                    node.getPosition()
                );
                var positionDirection = this._getRelativeDirection(
                    rootNode.getPosition(),
                    position
                );
                var siblings = graph.getSiblings(node);

                var sameParent = parent == graph.getParent(node);
                if (siblings.length == 0 && nodeDirection == positionDirection && sameParent) {
                    return [node.getOrder(), node.getPosition()];
                }
            }

            if (!position) {
                var right = this._getChildrenForOrder(parent, graph, 0);
                var left = this._getChildrenForOrder(parent, graph, 1);
            }
            // Filter nodes on one side..
            var order = position
                ? position.x > rootNode.getPosition().x
                    ? 0
                    : 1
                : right.length - left.length > 0
                ? 1
                : 0;
            var direction = order % 2 == 0 ? 1 : -1;

            // Exclude the dragged node (if set)
            var children = this._getChildrenForOrder(parent, graph, order).filter(function (child) {
                return child != node;
            });

            // No children?
            if (children.length == 0) {
                return [
                    order,
                    {
                        x:
                            parent.getPosition().x +
                            direction *
                                (parent.getSize().width / 2 +
                                    BalancedSorter.INTERNODE_HORIZONTAL_PADDING * 2),
                        y: parent.getPosition().y,
                    },
                ];
            }

            // Try to fit within ...
            var result = null;
            var last = children.getLast();
            position = position || { x: last.getPosition().x, y: last.getPosition().y + 1 };
            _.each(children, function (child, index) {
                var cpos = child.getPosition();
                if (position.y > cpos.y) {
                    let yOffset =
                        child == last
                            ? child.getSize().height + BalancedSorter.INTERNODE_VERTICAL_PADDING * 2
                            : (children[index + 1].getPosition().y - child.getPosition().y) / 2;
                    result = [child.getOrder() + 2, { x: cpos.x, y: cpos.y + yOffset }];
                }
            });

            // Position wasn't below any node, so it must be inserted above
            if (!result) {
                var first = children[0];
                result = [
                    position.x > 0 ? 0 : 1,
                    {
                        x: first.getPosition().x,
                        y:
                            first.getPosition().y -
                            first.getSize().height -
                            BalancedSorter.INTERNODE_VERTICAL_PADDING * 2,
                    },
                ];
            }

            return result;
        },

        /**
         * @param {} treeSet
         * @param {} parent
         * @param {} child
         * @param {} order
         */
        insert: function (treeSet, parent, child, order) {
            var children = this._getChildrenForOrder(parent, treeSet, order);

            // If no children, return 0 or 1 depending on the side
            if (children.length == 0) {
                child.setOrder(order % 2);
                return;
            }

            // Shift all the elements by two, so side is the same.
            // In case of balanced sorter, order don't need to be continuous...
            var max = 0;
            for (var i = 0; i < children.length; i++) {
                var node = children[i];
                max = Math.max(max, node.getOrder());
                if (node.getOrder() >= order) {
                    max = Math.max(max, node.getOrder() + 2);
                    node.setOrder(node.getOrder() + 2);
                }
            }

            var newOrder = order > max + 1 ? max + 2 : order;
            child.setOrder(newOrder);
        },

        /**
         * @param {} treeSet
         * @param {} node
         */
        detach: function (treeSet, node) {
            var parent = treeSet.getParent(node);
            // Filter nodes on one side..
            var children = this._getChildrenForOrder(parent, treeSet, node.getOrder());

            _.each(children, function (child, index) {
                if (child.getOrder() > node.getOrder()) {
                    child.setOrder(child.getOrder() - 2);
                }
            });
            node.setOrder(node.getOrder() % 2 == 0 ? 0 : 1);
        },

        /**
         * @param {} treeSet
         * @param {} node
         * @return offsets
         */
        computeOffsets: function (treeSet, node) {
            $assert(treeSet, 'treeSet can no be null.');
            $assert(node, 'node can no be null.');

            var children = this._getSortedChildren(treeSet, node);

            // Compute heights ...
            var heights = children
                .map(function (child) {
                    return {
                        id: child.getId(),
                        order: child.getOrder(),
                        width: child.getSize().width,
                        height: this._computeChildrenHeight(treeSet, child),
                    };
                }, this)
                .reverse();

            // Compute the center of the branch ...
            var totalPHeight = 0;
            var totalNHeight = 0;

            _.each(heights, function (elem) {
                if (elem.order % 2 == 0) {
                    totalPHeight += elem.height;
                } else {
                    totalNHeight += elem.height;
                }
            });
            var psum = totalPHeight / 2;
            var nsum = totalNHeight / 2;
            var ysum = 0;

            // Calculate the offsets ...
            var result = {};
            for (var i = 0; i < heights.length; i++) {
                var direction = heights[i].order % 2 ? -1 : 1;

                if (direction > 0) {
                    psum = psum - heights[i].height;
                    ysum = psum;
                } else {
                    nsum = nsum - heights[i].height;
                    ysum = nsum;
                }

                var yOffset = ysum + heights[i].height / 2;
                var xOffset =
                    direction *
                    (node.getSize().width / 2 +
                        heights[i].width / 2 +
                        +BalancedSorter.INTERNODE_HORIZONTAL_PADDING);

                $assert(!isNaN(xOffset), 'xOffset can not be null');
                $assert(!isNaN(yOffset), 'yOffset can not be null');

                result[heights[i].id] = { x: xOffset, y: yOffset };
            }
            return result;
        },

        /**
         * @param {} treeSet
         * @param {} node
         * @throw will throw an error if order elements are missing
         */
        verify: function (treeSet, node) {
            // Check that all is consistent ...
            var children = this._getChildrenForOrder(node, treeSet, node.getOrder());

            // All odd ordered nodes should be "continuous" by themselves
            // All even numbered nodes should be "continuous" by themselves
            var factor = node.getOrder() % 2 == 0 ? 2 : 1;
            for (var i = 0; i < children.length; i++) {
                var order = i == 0 && factor == 1 ? 1 : factor * i;
                $assert(
                    children[i].getOrder() == order,
                    'Missing order elements. Missing order: ' +
                        i * factor +
                        '. Parent:' +
                        node.getId() +
                        ',Node:' +
                        children[i].getId()
                );
            }
        },

        /**
         * @param {} treeSet
         * @param {} child
         * @return the direction of the child within the treeSet
         */
        getChildDirection: function (treeSet, child) {
            return child.getOrder() % 2 == 0 ? 1 : -1;
        },

        /**
         * @return {String} the print name of this class
         */
        toString: function () {
            return 'Balanced Sorter';
        },

        _getChildrenForOrder: function (parent, graph, order) {
            return this._getSortedChildren(graph, parent).filter(function (child) {
                return child.getOrder() % 2 == order % 2;
            });
        },

        _getVerticalPadding: function () {
            return BalancedSorter.INTERNODE_VERTICAL_PADDING;
        },
    }
);

/**
 * @constant
 * @type {Number}
 * @default
 */
BalancedSorter.INTERNODE_VERTICAL_PADDING = 5;
/**
 * @constant
 * @type {Number}
 * @default
 */
BalancedSorter.INTERNODE_HORIZONTAL_PADDING = 30;

export default BalancedSorter;