/*************************************************************
 *
 *  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 CHTMLmmultiscripts wrapper for the MmlMmultiscripts object
 *
 * @author dpvc@mathjax.org (Davide Cervone)
 */

import {CHTMLWrapper, Constructor} from '../Wrapper.js';
import {CHTMLmsubsup} from './msubsup.js';
import {CommonMmultiscripts, CommonMmultiscriptsMixin} from '../../common/Wrappers/mmultiscripts.js';
import {MmlMmultiscripts} from '../../../core/MmlTree/MmlNodes/mmultiscripts.js';
import {BBox} from '../BBox.js';
import {StyleList} from '../../common/CssStyles.js';

/*****************************************************************/
/**
 * The CHTMLmmultiscripts wrapper for the MmlMmultiscripts object
 *
 * @template N  The HTMLElement node class
 * @template T  The Text node class
 * @template D  The Document class
 */
export class CHTMLmmultiscripts<N, T, D> extends
CommonMmultiscriptsMixin<CHTMLWrapper<N, T, D>, Constructor<CHTMLmsubsup<N, T, D>>>(CHTMLmsubsup) {

    public static kind = MmlMmultiscripts.prototype.kind;

    public static styles: StyleList = {
        'mjx-prescripts': {
            display: 'inline-table',
            'padding-left': '.05em'   // scriptspace
        },
        'mjx-scripts': {
            display: 'inline-table',
            'padding-right': '.05em'   // scriptspace
        },
        'mjx-prescripts > mjx-row > mjx-cell': {
            'text-align': 'right'
        }
    };

    /*************************************************************/

    /**
     * @override
     */
    public toCHTML(parent: N) {
        const chtml = this.standardCHTMLnode(parent);
        const data = this.getScriptData();
        //
        //  Combine the bounding boxes of the pre- and post-scripts,
        //  and get the resulting baseline offsets
        //
        const sub = this.combinePrePost(data.sub, data.psub);
        const sup = this.combinePrePost(data.sup, data.psup);
        const [u, v, q] = this.getUVQ(data.base, sub, sup);
        //
        //  Place the pre-scripts, then the base, then the post-scripts
        //
        if (data.numPrescripts) {
            this.addScripts(u, -v, true, data.psub, data.psup, this.firstPrescript, data.numPrescripts);
        }
        this.childNodes[0].toCHTML(chtml);
        if (data.numScripts) {
            this.addScripts(u, -v, false, data.sub, data.sup, 1, data.numScripts);
        }
    }

    /**
     * Create a table with the super and subscripts properly separated and aligned.
     *
     * @param {number} u       The baseline offset for the superscripts
     * @param {number} v       The baseline offset for the subscripts
     * @param {boolean} isPre  True for prescripts, false for scripts
     * @param {BBox} sub       The subscript bounding box
     * @param {BBox} sup       The superscript bounding box
     * @param {number} i       The starting index for the scripts
     * @param {number} n       The number of sub/super-scripts
     */
    protected addScripts(u: number, v: number, isPre: boolean, sub: BBox, sup: BBox, i: number, n: number) {
        const adaptor = this.adaptor;
        const q = (u - sup.d) + (v - sub.h);             // separation of scripts
        const U = (u < 0 && v === 0 ? sub.h + u : u);    // vertical offset of table
        const rowdef = (q > 0 ? {style: {height: this.em(q)}} : {});
        const tabledef = (U ? {style: {'vertical-align': this.em(U)}} : {});
        const supRow = this.html('mjx-row');
        const sepRow = this.html('mjx-row', rowdef);
        const subRow = this.html('mjx-row');
        const name = 'mjx-' + (isPre ? 'pre' : '') + 'scripts';
        adaptor.append(this.chtml, this.html(name, tabledef, [supRow, sepRow, subRow]));
        let m = i + 2 * n;
        while (i < m) {
            this.childNodes[i++].toCHTML(adaptor.append(subRow, this.html('mjx-cell')) as N);
            this.childNodes[i++].toCHTML(adaptor.append(supRow, this.html('mjx-cell')) as N);
        }
    }

}