453 lines
14 KiB
JavaScript
453 lines
14 KiB
JavaScript
/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
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/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */
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/* Copyright 2012 Mozilla Foundation
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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'use strict';
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var bidi = PDFJS.bidi = (function bidiClosure() {
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// Character types for symbols from 0000 to 00FF.
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var baseTypes = [
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'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'S', 'B', 'S', 'WS',
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'B', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN',
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'BN', 'BN', 'B', 'B', 'B', 'S', 'WS', 'ON', 'ON', 'ET', 'ET', 'ET', 'ON',
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'ON', 'ON', 'ON', 'ON', 'ON', 'CS', 'ON', 'CS', 'ON', 'EN', 'EN', 'EN',
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'EN', 'EN', 'EN', 'EN', 'EN', 'EN', 'EN', 'ON', 'ON', 'ON', 'ON', 'ON',
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'ON', 'ON', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L',
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'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'ON', 'ON',
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'ON', 'ON', 'ON', 'ON', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L',
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'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L',
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'L', 'ON', 'ON', 'ON', 'ON', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'B', 'BN',
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'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN',
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'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN', 'BN',
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'BN', 'CS', 'ON', 'ET', 'ET', 'ET', 'ET', 'ON', 'ON', 'ON', 'ON', 'L', 'ON',
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'ON', 'ON', 'ON', 'ON', 'ET', 'ET', 'EN', 'EN', 'ON', 'L', 'ON', 'ON', 'ON',
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'EN', 'L', 'ON', 'ON', 'ON', 'ON', 'ON', 'L', 'L', 'L', 'L', 'L', 'L', 'L',
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'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L',
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'L', 'ON', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L',
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'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L',
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'L', 'L', 'L', 'ON', 'L', 'L', 'L', 'L', 'L', 'L', 'L', 'L'
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];
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// Character types for symbols from 0600 to 06FF
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var arabicTypes = [
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'CS', 'AL', 'ON', 'ON', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM',
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'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AN', 'AN', 'AN', 'AN', 'AN', 'AN', 'AN', 'AN', 'AN',
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'AN', 'ET', 'AN', 'AN', 'AL', 'AL', 'AL', 'NSM', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM',
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'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'NSM', 'ON', 'NSM',
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'NSM', 'NSM', 'NSM', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL',
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'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL', 'AL'
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];
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function isOdd(i) {
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return (i & 1) != 0;
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}
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function isEven(i) {
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return (i & 1) == 0;
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}
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function findUnequal(arr, start, value) {
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var j;
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for (var j = start, jj = arr.length; j < jj; ++j) {
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if (arr[j] != value)
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return j;
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}
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return j;
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}
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function setValues(arr, start, end, value) {
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for (var j = start; j < end; ++j) {
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arr[j] = value;
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}
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}
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function reverseValues(arr, start, end) {
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for (var i = start, j = end - 1; i < j; ++i, --j) {
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var temp = arr[i];
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arr[i] = arr[j];
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arr[j] = temp;
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}
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}
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function mirrorGlyphs(c) {
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/*
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# BidiMirroring-1.txt
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0028; 0029 # LEFT PARENTHESIS
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0029; 0028 # RIGHT PARENTHESIS
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003C; 003E # LESS-THAN SIGN
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003E; 003C # GREATER-THAN SIGN
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005B; 005D # LEFT SQUARE BRACKET
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005D; 005B # RIGHT SQUARE BRACKET
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007B; 007D # LEFT CURLY BRACKET
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007D; 007B # RIGHT CURLY BRACKET
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00AB; 00BB # LEFT-POINTING DOUBLE ANGLE QUOTATION MARK
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00BB; 00AB # RIGHT-POINTING DOUBLE ANGLE QUOTATION MARK
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*/
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switch (c) {
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case '(':
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return ')';
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case ')':
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return '(';
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case '<':
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return '>';
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case '>':
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return '<';
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case ']':
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return '[';
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case '[':
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return ']';
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case '}':
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return '{';
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case '{':
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return '}';
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case '\u00AB':
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return '\u00BB';
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case '\u00BB':
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return '\u00AB';
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default:
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return c;
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}
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}
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function BidiResult(str, isLTR) {
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this.str = str;
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this.ltr = isLTR;
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}
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function bidi(str, startLevel) {
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var isLTR = true;
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var strLength = str.length;
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if (strLength == 0)
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return new BidiResult(str, ltr);
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// get types, fill arrays
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var chars = [];
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var types = [];
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var oldtypes = [];
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var numBidi = 0;
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for (var i = 0; i < strLength; ++i) {
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chars[i] = str.charAt(i);
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var charCode = str.charCodeAt(i);
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var charType = 'L';
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if (charCode <= 0x00ff)
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charType = baseTypes[charCode];
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else if (0x0590 <= charCode && charCode <= 0x05f4)
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charType = 'R';
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else if (0x0600 <= charCode && charCode <= 0x06ff)
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charType = arabicTypes[charCode & 0xff];
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else if (0x0700 <= charCode && charCode <= 0x08AC)
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charType = 'AL';
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if (charType == 'R' || charType == 'AL' || charType == 'AN')
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numBidi++;
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oldtypes[i] = types[i] = charType;
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}
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// detect the bidi method
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// if there are no rtl characters then no bidi needed
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// if less than 30% chars are rtl then string is primarily ltr
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// if more than 30% chars are rtl then string is primarily rtl
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if (numBidi == 0) {
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isLTR = true;
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return new BidiResult(str, isLTR);
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}
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if (startLevel == -1) {
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if ((strLength / numBidi) < 0.3) {
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isLTR = true;
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startLevel = 0;
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} else {
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isLTR = false;
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startLevel = 1;
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}
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}
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var levels = [];
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for (var i = 0; i < strLength; ++i) {
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levels[i] = startLevel;
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}
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/*
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X1-X10: skip most of this, since we are NOT doing the embeddings.
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*/
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var e = isOdd(startLevel) ? 'R' : 'L';
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var sor = e;
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var eor = sor;
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/*
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W1. Examine each non-spacing mark (NSM) in the level run, and change the
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type of the NSM to the type of the previous character. If the NSM is at the
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start of the level run, it will get the type of sor.
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*/
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var lastType = sor;
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for (var i = 0; i < strLength; ++i) {
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if (types[i] == 'NSM')
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types[i] = lastType;
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else
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lastType = types[i];
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}
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/*
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W2. Search backwards from each instance of a European number until the
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first strong type (R, L, AL, or sor) is found. If an AL is found, change
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the type of the European number to Arabic number.
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*/
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var lastType = sor;
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for (var i = 0; i < strLength; ++i) {
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var t = types[i];
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if (t == 'EN')
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types[i] = (lastType == 'AL') ? 'AN' : 'EN';
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else if (t == 'R' || t == 'L' || t == 'AL')
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lastType = t;
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}
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/*
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W3. Change all ALs to R.
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*/
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for (var i = 0; i < strLength; ++i) {
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var t = types[i];
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if (t == 'AL')
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types[i] = 'R';
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}
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/*
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W4. A single European separator between two European numbers changes to a
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European number. A single common separator between two numbers of the same
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type changes to that type:
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*/
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for (var i = 1; i < strLength - 1; ++i) {
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if (types[i] == 'ES' && types[i - 1] == 'EN' && types[i + 1] == 'EN')
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types[i] = 'EN';
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if (types[i] == 'CS' && (types[i - 1] == 'EN' || types[i - 1] == 'AN') &&
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types[i + 1] == types[i - 1])
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types[i] = types[i - 1];
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}
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/*
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W5. A sequence of European terminators adjacent to European numbers changes
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to all European numbers:
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*/
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for (var i = 0; i < strLength; ++i) {
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if (types[i] == 'EN') {
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// do before
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for (var j = i - 1; j >= 0; --j) {
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if (types[j] != 'ET')
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break;
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types[j] = 'EN';
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}
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// do after
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for (var j = i + 1; j < strLength; --j) {
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if (types[j] != 'ET')
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break;
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types[j] = 'EN';
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}
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}
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}
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/*
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W6. Otherwise, separators and terminators change to Other Neutral:
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*/
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for (var i = 0; i < strLength; ++i) {
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var t = types[i];
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if (t == 'WS' || t == 'ES' || t == 'ET' || t == 'CS')
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types[i] = 'ON';
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}
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/*
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W7. Search backwards from each instance of a European number until the
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first strong type (R, L, or sor) is found. If an L is found, then change
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the type of the European number to L.
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*/
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var lastType = sor;
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for (var i = 0; i < strLength; ++i) {
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var t = types[i];
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if (t == 'EN')
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types[i] = (lastType == 'L') ? 'L' : 'EN';
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else if (t == 'R' || t == 'L')
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lastType = t;
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}
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/*
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N1. A sequence of neutrals takes the direction of the surrounding strong
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text if the text on both sides has the same direction. European and Arabic
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numbers are treated as though they were R. Start-of-level-run (sor) and
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end-of-level-run (eor) are used at level run boundaries.
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*/
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for (var i = 0; i < strLength; ++i) {
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if (types[i] == 'ON') {
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var end = findUnequal(types, i + 1, 'ON');
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var before = sor;
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if (i > 0)
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before = types[i - 1];
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var after = eor;
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if (end + 1 < strLength)
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after = types[end + 1];
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if (before != 'L')
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before = 'R';
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if (after != 'L')
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after = 'R';
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if (before == after)
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setValues(types, i, end, before);
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i = end - 1; // reset to end (-1 so next iteration is ok)
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}
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}
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/*
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N2. Any remaining neutrals take the embedding direction.
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*/
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for (var i = 0; i < strLength; ++i) {
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if (types[i] == 'ON')
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types[i] = e;
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}
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/*
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I1. For all characters with an even (left-to-right) embedding direction,
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those of type R go up one level and those of type AN or EN go up two
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levels.
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I2. For all characters with an odd (right-to-left) embedding direction,
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those of type L, EN or AN go up one level.
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*/
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for (var i = 0; i < strLength; ++i) {
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var t = types[i];
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if (isEven(levels[i])) {
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if (t == 'R') {
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levels[i] += 1;
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} else if (t == 'AN' || t == 'EN') {
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levels[i] += 2;
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}
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} else { // isOdd, so
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if (t == 'L' || t == 'AN' || t == 'EN') {
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levels[i] += 1;
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}
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}
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}
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/*
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L1. On each line, reset the embedding level of the following characters to
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the paragraph embedding level:
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segment separators,
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paragraph separators,
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any sequence of whitespace characters preceding a segment separator or
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paragraph separator, and any sequence of white space characters at the end
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of the line.
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*/
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// don't bother as text is only single line
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/*
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L2. From the highest level found in the text to the lowest odd level on
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each line, reverse any contiguous sequence of characters that are at that
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level or higher.
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*/
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// find highest level & lowest odd level
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var highestLevel = -1;
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var lowestOddLevel = 99;
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for (var i = 0, ii = levels.length; i < ii; ++i) {
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var level = levels[i];
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if (highestLevel < level)
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highestLevel = level;
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if (lowestOddLevel > level && isOdd(level))
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lowestOddLevel = level;
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}
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// now reverse between those limits
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for (var level = highestLevel; level >= lowestOddLevel; --level) {
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// find segments to reverse
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var start = -1;
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for (var i = 0, ii = levels.length; i < ii; ++i) {
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if (levels[i] < level) {
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if (start >= 0) {
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reverseValues(chars, start, i);
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start = -1;
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}
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} else if (start < 0) {
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start = i;
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}
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}
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if (start >= 0) {
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reverseValues(chars, start, levels.length);
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}
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}
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/*
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L3. Combining marks applied to a right-to-left base character will at this
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point precede their base character. If the rendering engine expects them to
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follow the base characters in the final display process, then the ordering
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of the marks and the base character must be reversed.
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*/
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// don't bother for now
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/*
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L4. A character that possesses the mirrored property as specified by
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Section 4.7, Mirrored, must be depicted by a mirrored glyph if the resolved
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directionality of that character is R.
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*/
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// don't mirror as characters are already mirrored in the pdf
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// Finally, return string
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var result = '';
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for (var i = 0, ii = chars.length; i < ii; ++i) {
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var ch = chars[i];
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if (ch != '<' && ch != '>')
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result += ch;
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}
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return new BidiResult(result, isLTR);
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}
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return bidi;
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})();
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