/*************************************************************
 *
 *  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 Configuration for the Base LaTeX parser.
 *
 * @author v.sorge@mathjax.org (Volker Sorge)
 */

import {Configuration} from '../Configuration.js';
import {MapHandler} from '../MapHandler.js';
import TexError from '../TexError.js';
import NodeUtil from '../NodeUtil.js';
import TexParser from '../TexParser.js';
import {ParseMethod} from '../Types.js';
import {CharacterMap} from '../SymbolMap.js';
import * as bitem from './BaseItems.js';
import {AbstractTags} from '../Tags.js';
import './BaseMappings.js';


/**
 * Remapping some ASCII characters to their Unicode operator equivalent.
 */
new CharacterMap('remap', null, {
  '-':   '\u2212',
  '*':   '\u2217',
  '`':   '\u2018'   // map ` to back quote
});


/**
 * Default handling of characters (as <mo> elements).
 * @param {TexParser} parser The calling parser.
 * @param {string} char The character to parse.
 */
export function Other(parser: TexParser, char: string) {
  const font = parser.stack.env['font'];
  let def = font ?
    // @test Other Font
    {mathvariant: parser.stack.env['font']} : {};
  const remap = (MapHandler.getMap('remap') as CharacterMap).
    lookup(char);
  // @test Other
  // @test Other Remap
  let mo = parser.create('token', 'mo', def, (remap ? remap.char : char));
  NodeUtil.setProperty(mo, 'fixStretchy', true);
  parser.configuration.addNode('fixStretchy', mo);
  parser.Push(mo);
};


/**
 * Handle undefined control sequence.
 * @param {TexParser} parser The calling parser.
 * @param {string} name The name of the control sequence.
 */
function csUndefined(parser: TexParser, name: string) {
  // @test Undefined-CS 
  throw new TexError('UndefinedControlSequence',
                      'Undefined control sequence %1', '\\' + name);
};


/**
 * Handle undefined environments.
 * @param {TexParser} parser The calling parser.
 * @param {string} name The name of the control sequence.
 */
function envUndefined(parser: TexParser, env: string) {
  // @test Undefined-Env
  throw new TexError('UnknownEnv', 'Unknown environment \'%1\'', env);
};


/**
 * @constructor
 * @extends {AbstractTags}
 */
export class BaseTags extends AbstractTags { }


/**
 * The base configuration.
 * @type {Configuration}
 */
export const BaseConfiguration: Configuration = Configuration.create(
  'base',
  {handler: {
    character: ['command', 'special', 'letter', 'digit'],
    delimiter: ['delimiter'],
    // Note, that the position of the delimiters here is important!
    macro: ['delimiter', 'macros', 'mathchar0mi', 'mathchar0mo', 'mathchar7'],
    environment: ['environment']
  },
   fallback: {
    character: Other,
    macro: csUndefined,
    environment: envUndefined},
   items: {
    // BaseItems
    [bitem.StartItem.prototype.kind]: bitem.StartItem,
    [bitem.StopItem.prototype.kind]: bitem.StopItem,
    [bitem.OpenItem.prototype.kind]: bitem.OpenItem,
    [bitem.CloseItem.prototype.kind]: bitem.CloseItem,
    [bitem.PrimeItem.prototype.kind]: bitem.PrimeItem,
    [bitem.SubsupItem.prototype.kind]: bitem.SubsupItem,
    [bitem.OverItem.prototype.kind]: bitem.OverItem,
    [bitem.LeftItem.prototype.kind]: bitem.LeftItem,
    [bitem.RightItem.prototype.kind]: bitem.RightItem,
    [bitem.BeginItem.prototype.kind]: bitem.BeginItem,
    [bitem.EndItem.prototype.kind]: bitem.EndItem,
    [bitem.StyleItem.prototype.kind]: bitem.StyleItem,
    [bitem.PositionItem.prototype.kind]: bitem.PositionItem,
    [bitem.CellItem.prototype.kind]: bitem.CellItem,
    [bitem.MmlItem.prototype.kind]: bitem.MmlItem,
    [bitem.FnItem.prototype.kind]: bitem.FnItem,
    [bitem.NotItem.prototype.kind]: bitem.NotItem,
    [bitem.DotsItem.prototype.kind]: bitem.DotsItem,
    [bitem.ArrayItem.prototype.kind]: bitem.ArrayItem,
    [bitem.EqnArrayItem.prototype.kind]: bitem.EqnArrayItem,
    [bitem.EquationItem.prototype.kind]: bitem.EquationItem
   },
   options: {maxMacros: 1000,
             baseURL: (typeof(document) === 'undefined' ||
                       document.getElementsByTagName('base').length === 0) ?
             '' : String(document.location).replace(/#.*$/, '')
            },
   tags: {base: BaseTags}});