/*************************************************************
 *
 *  Copyright (c) 2018 The MathJax Consortium
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  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.
 */

/**
 * @fileoverview  Implements the CommonMfenced wrapper mixin for the MmlMfenced object
 *
 * @author dpvc@mathjax.org (Davide Cervone)
 */

import {AnyWrapper, WrapperConstructor, Constructor} from '../Wrapper.js';
import {CommonInferredMrow} from './mrow.js';
import {MmlNode, AbstractMmlNode, AttributeList} from '../../../core/MmlTree/MmlNode.js';
import {MmlMfenced} from '../../../core/MmlTree/MmlNodes/mfenced.js';
import {BBox} from '../BBox.js';

/*****************************************************************/
/**
 * The CommonMfenced interface
 */
export interface CommonMfenced extends AnyWrapper {
    /**
     * An mrow to use for the layout of the mfenced
     */
    mrow: CommonInferredMrow;

    /**
     * Creates the mrow wrapper to use for the layout
     */
    createMrow(): void;

    /**
     * Populate the mrow with wrapped mo elements interleaved
     *   with the mfenced children (the mo's are already created
     *   in the mfenced object)
     */
    addMrowChildren(): void;

    /**
     * Wrap an mo element and push it onto the mrow
     *
     * @param {MmlNode} node  The mo element to push on the mrow
     */
    addMo(node: MmlNode): void;
}

/**
 * Shorthand for the CommonMfenced constructor
 */
export type MfencedConstructor = Constructor<CommonMfenced>;

/*****************************************************************/
/**
 * The CommonMfenced wrapper mixin for the MmlMfenced object
 *
 * @template T  The Wrapper class constructor type
 */
export function CommonMfencedMixin<T extends WrapperConstructor>(Base: T): MfencedConstructor & T {
    return class extends Base {

        /**
         * An mrow to use for the layout of the mfenced
         */
        public mrow: CommonInferredMrow = null;

        /**
         * @override
         * @constructor
         */
        constructor(...args: any[]) {
            super(...args);
            this.createMrow();
            this.addMrowChildren();
        }

        /**
         * Creates the mrow wrapper to use for the layout
         */
        public createMrow() {
            const mmlFactory = (this.node as AbstractMmlNode).factory;
            const mrow = mmlFactory.create('inferredMrow');
            mrow.inheritAttributesFrom(this.node);
            this.mrow = this.wrap(mrow) as CommonInferredMrow;
            this.mrow.parent = this;
        }

        /**
         * Populate the mrow with wrapped mo elements interleaved
         *   with the mfenced children (the mo's are already created
         *   in the mfenced object)
         */
        public addMrowChildren() {
            const mfenced = this.node as MmlMfenced;
            const mrow = this.mrow;
            this.addMo(mfenced.open);
            if (this.childNodes.length) {
                mrow.childNodes.push(this.childNodes[0]);
            }
            let i = 0;
            for (const child of this.childNodes.slice(1)) {
                this.addMo(mfenced.separators[i++]);
                mrow.childNodes.push(child);
            }
            this.addMo(mfenced.close);
            mrow.stretchChildren();
        }

        /**
         * Wrap an mo element and push it onto the mrow
         *
         * @param {MmlNode} node  The mo element to push on the mrow
         */
        public addMo(node: MmlNode) {
            if (!node) return;
            const mo = this.wrap(node);
            this.mrow.childNodes.push(mo);
            mo.parent = this.mrow;
        }

        /**
         * @override
         */
        public computeBBox(bbox: BBox, recompute: boolean = false) {
            bbox.updateFrom(this.mrow.getBBox());
            this.setChildPWidths(recompute);
        }

    };

}