/*
|
* 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.
|
*/
|
/*namespace com.google.zxing.common {*/
|
/*import java.nio.charset.Charset;*/
|
/*import java.util.Map;*/
|
import DecodeHintType from '../DecodeHintType';
|
import CharacterSetECI from './CharacterSetECI';
|
import StringEncoding from '../util/StringEncoding';
|
/**
|
* Common string-related functions.
|
*
|
* @author Sean Owen
|
* @author Alex Dupre
|
*/
|
export default class StringUtils {
|
// SHIFT_JIS.equalsIgnoreCase(PLATFORM_DEFAULT_ENCODING) ||
|
// EUC_JP.equalsIgnoreCase(PLATFORM_DEFAULT_ENCODING);
|
static castAsNonUtf8Char(code, encoding = null) {
|
// ISO 8859-1 is the Java default as UTF-8 is JavaScripts
|
// you can see this method as a Java version of String.fromCharCode
|
const e = encoding ? encoding.getName() : this.ISO88591;
|
// use passed format (fromCharCode will return UTF8 encoding)
|
return StringEncoding.decode(new Uint8Array([code]), e);
|
}
|
/**
|
* @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
|
*/
|
static guessEncoding(bytes, hints) {
|
if (hints !== null && hints !== undefined && undefined !== hints.get(DecodeHintType.CHARACTER_SET)) {
|
return hints.get(DecodeHintType.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.
|
const length = bytes.length;
|
let canBeISO88591 = true;
|
let canBeShiftJIS = true;
|
let canBeUTF8 = true;
|
let utf8BytesLeft = 0;
|
// int utf8LowChars = 0
|
let utf2BytesChars = 0;
|
let utf3BytesChars = 0;
|
let utf4BytesChars = 0;
|
let sjisBytesLeft = 0;
|
// int sjisLowChars = 0
|
let sjisKatakanaChars = 0;
|
// int sjisDoubleBytesChars = 0
|
let sjisCurKatakanaWordLength = 0;
|
let sjisCurDoubleBytesWordLength = 0;
|
let sjisMaxKatakanaWordLength = 0;
|
let sjisMaxDoubleBytesWordLength = 0;
|
// int isoLowChars = 0
|
// int isoHighChars = 0
|
let isoHighOther = 0;
|
const utf8bom = bytes.length > 3 &&
|
bytes[0] === /*(byte) */ 0xEF &&
|
bytes[1] === /*(byte) */ 0xBB &&
|
bytes[2] === /*(byte) */ 0xBF;
|
for (let i = 0; i < length && (canBeISO88591 || canBeShiftJIS || canBeUTF8); i++) {
|
const 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;
|
}
|
/**
|
*
|
* @see https://stackoverflow.com/a/13439711/4367683
|
*
|
* @param append The new string to append.
|
* @param args Argumets values to be formated.
|
*/
|
static format(append, ...args) {
|
let i = -1;
|
function callback(exp, p0, p1, p2, p3, p4) {
|
if (exp === '%%')
|
return '%';
|
if (args[++i] === undefined)
|
return undefined;
|
exp = p2 ? parseInt(p2.substr(1)) : undefined;
|
let base = p3 ? parseInt(p3.substr(1)) : undefined;
|
let val;
|
switch (p4) {
|
case 's':
|
val = args[i];
|
break;
|
case 'c':
|
val = args[i][0];
|
break;
|
case 'f':
|
val = parseFloat(args[i]).toFixed(exp);
|
break;
|
case 'p':
|
val = parseFloat(args[i]).toPrecision(exp);
|
break;
|
case 'e':
|
val = parseFloat(args[i]).toExponential(exp);
|
break;
|
case 'x':
|
val = parseInt(args[i]).toString(base ? base : 16);
|
break;
|
case 'd':
|
val = parseFloat(parseInt(args[i], base ? base : 10).toPrecision(exp)).toFixed(0);
|
break;
|
}
|
val = typeof val === 'object' ? JSON.stringify(val) : (+val).toString(base);
|
let size = parseInt(p1); /* padding size */
|
let ch = p1 && (p1[0] + '') === '0' ? '0' : ' '; /* isnull? */
|
while (val.length < size)
|
val = p0 !== undefined ? val + ch : ch + val; /* isminus? */
|
return val;
|
}
|
let regex = /%(-)?(0?[0-9]+)?([.][0-9]+)?([#][0-9]+)?([scfpexd%])/g;
|
return append.replace(regex, callback);
|
}
|
/**
|
*
|
*/
|
static getBytes(str, encoding) {
|
return StringEncoding.encode(str, encoding);
|
}
|
/**
|
* Returns the charcode at the specified index or at index zero.
|
*/
|
static getCharCode(str, index = 0) {
|
return str.charCodeAt(index);
|
}
|
/**
|
* Returns char for given charcode
|
*/
|
static getCharAt(charCode) {
|
return String.fromCharCode(charCode);
|
}
|
}
|
StringUtils.SHIFT_JIS = CharacterSetECI.SJIS.getName(); // "SJIS"
|
StringUtils.GB2312 = 'GB2312';
|
StringUtils.ISO88591 = CharacterSetECI.ISO8859_1.getName(); // "ISO8859_1"
|
StringUtils.EUC_JP = 'EUC_JP';
|
StringUtils.UTF8 = CharacterSetECI.UTF8.getName(); // "UTF8"
|
StringUtils.PLATFORM_DEFAULT_ENCODING = StringUtils.UTF8; // "UTF8"//Charset.defaultCharset().name()
|
StringUtils.ASSUME_SHIFT_JIS = false;
|
