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angular-weblineindia-qrcode-scanner

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"use strict"; /* * Copyright (C) 2010 ZXing authors * * 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. */ Object.defineProperty(exports, "__esModule", { value: true }); /*namespace com.google.zxing.common {*/ /*import java.nio.charset.Charset;*/ /*import java.util.Map;*/ var DecodeHintType_1 = require("../DecodeHintType"); var CharacterSetECI_1 = require("./CharacterSetECI"); /** * Common string-related functions. * * @author Sean Owen * @author Alex Dupre */ var StringUtils = /** @class */ (function () { function StringUtils() { } // SHIFT_JIS.equalsIgnoreCase(PLATFORM_DEFAULT_ENCODING) || // EUC_JP.equalsIgnoreCase(PLATFORM_DEFAULT_ENCODING); StringUtils.prototype.StringUtils = function () { }; /** * @param bytes bytes encoding a string, whose encoding should be guessed * @param hints decode hints if applicable * @return name of guessed encoding; at the moment will only guess one of: * {@link #SHIFT_JIS}, {@link #UTF8}, {@link #ISO88591}, or the platform * default encoding if none of these can possibly be correct */ StringUtils.guessEncoding = function (bytes, hints) { if (hints !== null && hints !== undefined && undefined !== hints.get(DecodeHintType_1.default.CHARACTER_SET)) { return hints.get(DecodeHintType_1.default.CHARACTER_SET).toString(); } // For now, merely tries to distinguish ISO-8859-1, UTF-8 and Shift_JIS, // which should be by far the most common encodings. var length = bytes.length; var canBeISO88591 = true; var canBeShiftJIS = true; var canBeUTF8 = true; var utf8BytesLeft = 0; // int utf8LowChars = 0 var utf2BytesChars = 0; var utf3BytesChars = 0; var utf4BytesChars = 0; var sjisBytesLeft = 0; // int sjisLowChars = 0 var sjisKatakanaChars = 0; // int sjisDoubleBytesChars = 0 var sjisCurKatakanaWordLength = 0; var sjisCurDoubleBytesWordLength = 0; var sjisMaxKatakanaWordLength = 0; var sjisMaxDoubleBytesWordLength = 0; // int isoLowChars = 0 // int isoHighChars = 0 var isoHighOther = 0; var utf8bom = bytes.length > 3 && bytes[0] === /*(byte) */ 0xEF && bytes[1] === /*(byte) */ 0xBB && bytes[2] === /*(byte) */ 0xBF; for (var i = 0; i < length && (canBeISO88591 || canBeShiftJIS || canBeUTF8); i++) { var value = bytes[i] & 0xFF; // UTF-8 stuff if (canBeUTF8) { if (utf8BytesLeft > 0) { if ((value & 0x80) === 0) { canBeUTF8 = false; } else { utf8BytesLeft--; } } else if ((value & 0x80) !== 0) { if ((value & 0x40) === 0) { canBeUTF8 = false; } else { utf8BytesLeft++; if ((value & 0x20) === 0) { utf2BytesChars++; } else { utf8BytesLeft++; if ((value & 0x10) === 0) { utf3BytesChars++; } else { utf8BytesLeft++; if ((value & 0x08) === 0) { utf4BytesChars++; } else { canBeUTF8 = false; } } } } } // else { // utf8LowChars++ // } } // ISO-8859-1 stuff if (canBeISO88591) { if (value > 0x7F && value < 0xA0) { canBeISO88591 = false; } else if (value > 0x9F) { if (value < 0xC0 || value === 0xD7 || value === 0xF7) { isoHighOther++; } // else { // isoHighChars++ // } } // else { // isoLowChars++ // } } // Shift_JIS stuff if (canBeShiftJIS) { if (sjisBytesLeft > 0) { if (value < 0x40 || value === 0x7F || value > 0xFC) { canBeShiftJIS = false; } else { sjisBytesLeft--; } } else if (value === 0x80 || value === 0xA0 || value > 0xEF) { canBeShiftJIS = false; } else if (value > 0xA0 && value < 0xE0) { sjisKatakanaChars++; sjisCurDoubleBytesWordLength = 0; sjisCurKatakanaWordLength++; if (sjisCurKatakanaWordLength > sjisMaxKatakanaWordLength) { sjisMaxKatakanaWordLength = sjisCurKatakanaWordLength; } } else if (value > 0x7F) { sjisBytesLeft++; // sjisDoubleBytesChars++ sjisCurKatakanaWordLength = 0; sjisCurDoubleBytesWordLength++; if (sjisCurDoubleBytesWordLength > sjisMaxDoubleBytesWordLength) { sjisMaxDoubleBytesWordLength = sjisCurDoubleBytesWordLength; } } else { // sjisLowChars++ sjisCurKatakanaWordLength = 0; sjisCurDoubleBytesWordLength = 0; } } } if (canBeUTF8 && utf8BytesLeft > 0) { canBeUTF8 = false; } if (canBeShiftJIS && sjisBytesLeft > 0) { canBeShiftJIS = false; } // Easy -- if there is BOM or at least 1 valid not-single byte character (and no evidence it can't be UTF-8), done if (canBeUTF8 && (utf8bom || utf2BytesChars + utf3BytesChars + utf4BytesChars > 0)) { return StringUtils.UTF8; } // Easy -- if assuming Shift_JIS or at least 3 valid consecutive not-ascii characters (and no evidence it can't be), done if (canBeShiftJIS && (StringUtils.ASSUME_SHIFT_JIS || sjisMaxKatakanaWordLength >= 3 || sjisMaxDoubleBytesWordLength >= 3)) { return StringUtils.SHIFT_JIS; } // Distinguishing Shift_JIS and ISO-8859-1 can be a little tough for short words. The crude heuristic is: // - If we saw // - only two consecutive katakana chars in the whole text, or // - at least 10% of bytes that could be "upper" not-alphanumeric Latin1, // - then we conclude Shift_JIS, else ISO-8859-1 if (canBeISO88591 && canBeShiftJIS) { return (sjisMaxKatakanaWordLength === 2 && sjisKatakanaChars === 2) || isoHighOther * 10 >= length ? StringUtils.SHIFT_JIS : StringUtils.ISO88591; } // Otherwise, try in order ISO-8859-1, Shift JIS, UTF-8 and fall back to default platform encoding if (canBeISO88591) { return StringUtils.ISO88591; } if (canBeShiftJIS) { return StringUtils.SHIFT_JIS; } if (canBeUTF8) { return StringUtils.UTF8; } // Otherwise, we take a wild guess with platform encoding return StringUtils.PLATFORM_DEFAULT_ENCODING; }; StringUtils.SHIFT_JIS = CharacterSetECI_1.default.SJIS.getName(); // "SJIS" StringUtils.GB2312 = 'GB2312'; StringUtils.ISO88591 = CharacterSetECI_1.default.ISO8859_1.getName(); // "ISO8859_1" StringUtils.EUC_JP = 'EUC_JP'; StringUtils.UTF8 = CharacterSetECI_1.default.UTF8.getName(); // "UTF8" StringUtils.PLATFORM_DEFAULT_ENCODING = StringUtils.UTF8; // "UTF8"//Charset.defaultCharset().name() StringUtils.ASSUME_SHIFT_JIS = false; return StringUtils; }()); exports.default = StringUtils; //# sourceMappingURL=StringUtils.js.map