cleanup; rename vars; fix deflate
This commit is contained in:
rolux
parent
a393591741
commit
ad3b50cb82
1 changed files with 354 additions and 387 deletions
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@ -1,404 +1,371 @@
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'use strict';
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(function() {
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function cap(width, height) {
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// returns maximum encoding capacity of an image
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return parseInt(width * height * 3/8) - 4;
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/*@
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Ox.encodeBase26 <b> Encode a number as bijective base26
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See <a href="http://en.wikipedia.org/wiki/Bijective_numeration">
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Bijective numeration</a>.
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> Ox.encodeBase26(4461)
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'FOO'
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@*/
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Ox.encodeBase26 = function(number) {
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var string = '';
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while (number) {
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string = String.fromCharCode(64 + number % 26) + string;
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number = parseInt(number / 26);
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}
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return string;
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};
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function seek(data, px) {
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// returns this, or the next, opaque pixel
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while (data[px * 4 + 3] < 255) {
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if (++px * 4 == data.length) {
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throwPNGError('de');
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}
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}
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return px;
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}
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/*@
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Ox.decodeBase26 <f> Decodes a bijective base26-encoded number
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See <a href="http://en.wikipedia.org/wiki/Bijective_numeration">
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Bijective numeration</a>.
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> Ox.decodeBase26('foo')
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4461
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@*/
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Ox.decodeBase26 = function(string) {
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return string.toUpperCase().split('').reverse().reduce(function(p, c, i) {
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return p + (c.charCodeAt(0) - 64) * Math.pow(26, i);
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}, 0);
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};
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function xor(byte) {
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// returns "1"-bits-in-byte % 2
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// use: num.toString(2).replace(/0/g, '').length % 2
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var xor = 0;
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Ox.range(8).forEach(function(i) {
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xor ^= byte >> i & 1;
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});
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return xor;
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}
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/*@
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Ox.encodeBase32 <b> Encode a number as base32
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See <a href="http://www.crockford.com/wrmg/base32.html">Base 32</a>.
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> Ox.encodeBase32(15360)
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'F00'
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> Ox.encodeBase32(33819)
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'110V'
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@*/
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Ox.encodeBase32 = function(number) {
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return Ox.map(number.toString(32), function(character) {
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return Ox.BASE_32_DIGITS[parseInt(character, 32)];
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});
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};
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function throwPNGError(str) {
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throw new RangeError(
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'PNG codec can\'t ' +
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(str == 'en' ? 'encode data' : 'decode image')
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/*@
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Ox.decodeBase32 <f> Decodes a base32-encoded number
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See <a href="http://www.crockford.com/wrmg/base32.html">Base 32</a>.
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> Ox.decodeBase32('foo')
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15360
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> Ox.decodeBase32('ILOU')
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33819
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> Ox.decodeBase32('?').toString()
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'NaN'
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@*/
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Ox.decodeBase32 = function(string) {
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return parseInt(Ox.map(string.toUpperCase(), function(character) {
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var index = Ox.BASE_32_DIGITS.indexOf(
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Ox.BASE_32_ALIASES[character] || character
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);
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}
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return (index == -1 ? ' ' : index).toString(32);
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}), 32);
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};
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function throwUTF8Error(byte, pos) {
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/*@
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Ox.encodeBase64 <f> Encode a number as base64
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> Ox.encodeBase64(32394)
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'foo'
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@*/
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Ox.encodeBase64 = function(number) {
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return btoa(Ox.encodeBase256(number)).replace(/=/g, '');
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};
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/*@
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Ox.decodeBase64 <f> Decodes a base64-encoded number
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> Ox.decodeBase64('foo')
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32394
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@*/
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Ox.decodeBase64 = function(string) {
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return Ox.decodeBase256(atob(string));
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};
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/*@
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Ox.encodeBase128 <f> Encode a number as base128
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> Ox.encodeBase128(1685487)
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'foo'
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@*/
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Ox.encodeBase128 = function(number) {
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var string = '';
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while (number) {
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string = Ox.char(number & 127) + string;
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number >>= 7;
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}
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return string;
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};
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/*@
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Ox.decodeBase128 <f> Decode a base128-encoded number
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> Ox.decodeBase128('foo')
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1685487
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@*/
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Ox.decodeBase128 = function(string) {
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return string.split('').reverse().reduce(function(p, c, i) {
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return p + (c.charCodeAt(0) << i * 7);
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}, 0);
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};
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/*@
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Ox.encodeBase256 <f> Encode a number as base256
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> Ox.encodeBase256(6713199)
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'foo'
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@*/
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Ox.encodeBase256 = function(number) {
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var string = '';
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while (number) {
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string = Ox.char(number & 255) + string;
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number >>= 8;
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}
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return string;
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};
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/*@
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Ox.decodeBase256 <f> Decode a base256-encoded number
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> Ox.decodeBase256('foo')
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6713199
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@*/
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Ox.decodeBase256 = function(string) {
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return string.split('').reverse().reduce(function(p, c, i) {
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return p + (c.charCodeAt(0) << i * 8);
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}, 0);
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};
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/*@
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Ox.encodeDeflate <f> Encodes a string, using deflate
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Since PNGs are deflate-encoded, the <code>canvas</code> object's
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<code>toDataURL</code> method provides an efficient implementation.
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The string is encoded as UTF-8 and written to the RGB channels of a
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canvas element, then the PNG dataURL is decoded from base64, and some
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head, tail and chunk names are removed.
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(str) -> <s> The encoded string
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str <s> The string to be encoded
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# Test with: Ox.decodeDeflate(Ox.encodeDeflate('foo'), alert)
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@*/
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Ox.encodeDeflate = function(string, callback) {
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// Make sure we can encode the full unicode range of characters.
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string = Ox.encodeUTF8(string);
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// We can only safely write to RGB, so we need 1 pixel for 3 bytes.
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// The string length may not be a multiple of 3, so we need to encode
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// the number of padding bytes (1 byte), the string, and non-0-bytes
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// as padding, so that the combined length becomes a multiple of 3.
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var length = 1 + string.length, c = Ox.canvas(Math.ceil(length / 3), 1),
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data, idat, pad = (3 - length % 3) % 3;
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string = Ox.char(pad) + string + Ox.repeat('\u00FF', pad);
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Ox.loop(c.data.length, function(i) {
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// Write character codes into RGB, and 255 into ALPHA
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c.data[i] = i % 4 < 3 ? string.charCodeAt(i - parseInt(i / 4)) : 255;
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});
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c.context.putImageData(c.imageData, 0, 0);
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// Get the PNG data from the data URL and decode it from base64.
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string = atob(c.canvas.toDataURL().split(',')[1]);
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// Discard bytes 0 to 15 (8 bytes PNG signature, 4 bytes IHDR length, 4
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// bytes IHDR name), keep bytes 16 to 19 (width), discard bytes 20 to 29
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// (4 bytes height, 5 bytes flags), keep bytes 29 to 32 (IHDR checksum),
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// keep the rest (IDAT chunks), discard the last 12 bytes (IEND chunk).
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data = string.slice(16, 20) + string.slice(29, 33);
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idat = string.slice(33, -12);
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while (idat) {
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// Each IDAT chunk is 4 bytes length, 4 bytes name, length bytes
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// data and 4 bytes checksum. We can discard the name parts.
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length = idat.slice(0, 4);
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data += length + idat.slice(8, 12 + (
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length = Ox.decodeBase256(length)
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));
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idat = idat.slice(12 + length);
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}
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// Allow for async use, symmetrical to Ox.decodeDeflate
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callback && callback(data);
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return data;
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};
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/*@
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Ox.decodeDeflate <f> Decodes an deflate-encoded string
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Since PNGs are deflate-encoded, the <code>canvas</code> object's
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<code>drawImage</code> method provides an efficient implementation. The
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string will be wrapped as a PNG dataURL, encoded as base64, and drawn
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onto a canvas element, then the RGB channels will be read, and the
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result will be decoded from UTF8.
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(str) -> <u> undefined
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str <s> The string to be decoded
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callback <f> Callback function
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str <s> The decoded string
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@*/
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Ox.decodeDeflate = function(string, callback) {
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var image = new Image(),
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// PNG file signature and IHDR chunk
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data = '\u0089PNG\r\n\u001A\n\u0000\u0000\u0000\u000DIHDR'
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+ string.slice(0, 4) + '\u0000\u0000\u0000\u0001'
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+ '\u0008\u0006\u0000\u0000\u0000' + string.slice(4, 8),
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// IDAT chunks
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idat = string.slice(8), length;
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function error() {
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throw new RangeError('Deflate codec can\'t decode data.');
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}
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while (idat) {
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// Reinsert the IDAT chunk names
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length = idat.slice(0, 4);
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data += length + 'IDAT' + idat.slice(4, 8 + (
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length = Ox.decodeBase256(length)
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));
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idat = idat.slice(8 + length);
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}
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// IEND chunk
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data += '\u0000\u0000\u0000\u0000IEND\u00AE\u0042\u0060\u0082';
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// Unfortunately, we can't synchronously set the source of an image,
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// draw it onto a canvas, and read its data.
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image.onload = function() {
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string = Ox.toArray(Ox.canvas(image).data).map(function(value, index) {
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// Read one character per RGB byte, ignore ALPHA.
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return index % 4 < 3 ? Ox.char(value) : '';
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}).join('');
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try {
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// Parse the first byte as number of bytes to chop at the end,
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// and the rest, without these bytes, as an UTF8-encoded string.
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string = Ox.decodeUTF8(string.slice(1, -string.charCodeAt(0)));
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} catch (e) {
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error();
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}
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callback(string);
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}
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image.onerror = error;
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image.src = 'data:image/png;base64,' + btoa(data);
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};
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/*@
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Ox.encodeHTML <f> HTML-encodes a string
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> Ox.encodeHTML('\'<"&">\'')
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''<"&">''
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> Ox.encodeHTML('äbçdê')
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'äbçdê'
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@*/
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Ox.encodeHTML = function(str) {
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return Ox.map(str.toString(), function(v) {
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var code = v.charCodeAt(0);
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return code < 128
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? (v in Ox.HTML_ENTITIES ? Ox.HTML_ENTITIES[v] : v)
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: '&#x' + Ox.pad(code.toString(16).toUpperCase(), 4) + ';';
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});
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};
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/*@
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Ox.decodeHTML <f> Decodes an HTML-encoded string
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> Ox.decodeHTML(''<"&">'')
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'\'<"&">\''
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> Ox.decodeHTML(''<"&">'')
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'\'<"&">\''
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> Ox.decodeHTML('äbçdê')
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'äbçdê'
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> Ox.decodeHTML('äbçdê')
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'äbçdê'
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> Ox.decodeHTML('<b>bold</b>')
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'<b>bold</b>'
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@*/
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Ox.decodeHTML = function(str) {
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// relies on dom, but shorter than using this:
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// http://www.w3.org/TR/html5/named-character-references.html
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return Ox.decodeHTMLEntities(Ox.element('<div>').html(str).html());
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};
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Ox.encodeHTMLEntities = function(str) {
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return str.replace(
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new RegExp('(' + Object.keys(Ox.HTML_ENTITIES).join('|') + ')', 'g'),
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function(match) {
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return Ox.HTML_ENTITIES[match];
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}
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);
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};
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Ox.decodeHTMLEntities = function(str) {
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return str.replace(
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new RegExp('(' + Ox.values(Ox.HTML_ENTITIES).join('|') + ')', 'g'),
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function(match) {
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return Ox.keyOf(Ox.HTML_ENTITIES, match);
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}
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);
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};
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/*@
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Ox.encodeUTF8 <f> Encodes a string as UTF-8
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see http://en.wikipedia.org/wiki/UTF-8
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(string) -> <s> UTF-8 encoded string
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string <s> Any string
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> Ox.encodeUTF8("YES")
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"YES"
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> Ox.encodeUTF8("¥€$")
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"\u00C2\u00A5\u00E2\u0082\u00AC\u0024"
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@*/
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Ox.encodeUTF8 = function(str) {
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return Ox.map(str, function(chr) {
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var code = chr.charCodeAt(0),
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str = '';
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if (code < 128) {
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str = chr;
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} else if (code < 2048) {
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str = String.fromCharCode(code >> 6 | 192)
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+ String.fromCharCode(code & 63 | 128);
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} else {
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str = String.fromCharCode(code >> 12 | 224)
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+ String.fromCharCode(code >> 6 & 63 | 128)
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+ String.fromCharCode(code & 63 | 128);
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}
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return str;
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});
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};
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/*@
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Ox.decodeUTF8 <f> Decodes an UTF-8-encoded string
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see http://en.wikipedia.org/wiki/UTF-8
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(utf8) -> <s> string
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utf8 <s> Any UTF-8-encoded string
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> Ox.decodeUTF8('YES')
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'YES'
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> Ox.decodeUTF8('\u00C2\u00A5\u00E2\u0082\u00AC\u0024')
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'¥€$'
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@*/
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Ox.decodeUTF8 = function(string) {
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var code, i = 0, length = string.length, ret = '';
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function error(byte, position) {
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throw new RangeError(
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'UTF-8 codec can\'t decode byte 0x' +
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byte.toString(16).toUpperCase() + ' at position ' + pos
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byte.toString(16).toUpperCase() + ' at position ' + position
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);
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}
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/*@
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Ox.encodeBase26 <b> Encode a number as bijective base26
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See <a href="http://en.wikipedia.org/wiki/Bijective_numeration">
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Bijective numeration</a>.
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> Ox.encodeBase26(4461)
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'FOO'
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@*/
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Ox.encodeBase26 = function(num) {
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var ret = '';
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while (num) {
|
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ret = String.fromCharCode(64 + num % 26) + ret;
|
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num = parseInt(num / 26);
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}
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return ret;
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};
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/*@
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Ox.decodeBase26 <f> Decodes a bijective base26-encoded number
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See <a href="http://en.wikipedia.org/wiki/Bijective_numeration">
|
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Bijective numeration</a>.
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> Ox.decodeBase26('foo')
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4461
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@*/
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Ox.decodeBase26 = function(str) {
|
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return str.toUpperCase().split('').reverse().reduce(function(p, v, i) {
|
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return p + (v.charCodeAt(0) - 64) * Math.pow(26, i);
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}, 0);
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};
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/*@
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Ox.encodeBase32 <b> Encode a number as base32
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||||
See <a href="http://www.crockford.com/wrmg/base32.html">Base 32</a>.
|
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> Ox.encodeBase32(15360)
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'F00'
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> Ox.encodeBase32(33819)
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'110V'
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@*/
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Ox.encodeBase32 = function(num) {
|
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return Ox.map(num.toString(32), function(char) {
|
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return Ox.BASE_32_DIGITS[parseInt(char, 32)];
|
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});
|
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};
|
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|
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/*@
|
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Ox.decodeBase32 <f> Decodes a base32-encoded number
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||||
See <a href="http://www.crockford.com/wrmg/base32.html">Base 32</a>.
|
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> Ox.decodeBase32('foo')
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15360
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> Ox.decodeBase32('ILOU')
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33819
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> Ox.decodeBase32('?').toString()
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'NaN'
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@*/
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Ox.decodeBase32 = function(str) {
|
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return parseInt(Ox.map(str.toUpperCase(), function(char) {
|
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var index = Ox.BASE_32_DIGITS.indexOf(
|
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Ox.BASE_32_ALIASES[char] || char
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);
|
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return (index == -1 ? ' ' : index).toString(32);
|
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}), 32);
|
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};
|
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/*@
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Ox.encodeBase64 <f> Encode a number as base64
|
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> Ox.encodeBase64(32394)
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'foo'
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@*/
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Ox.encodeBase64 = function(num) {
|
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return btoa(Ox.encodeBase256(num)).replace(/=/g, '');
|
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};
|
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|
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/*@
|
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Ox.decodeBase64 <f> Decodes a base64-encoded number
|
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> Ox.decodeBase64('foo')
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32394
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@*/
|
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Ox.decodeBase64 = function(str) {
|
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return Ox.decodeBase256(atob(str));
|
||||
};
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/*@
|
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Ox.encodeBase128 <f> Encode a number as base128
|
||||
> Ox.encodeBase128(1685487)
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'foo'
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@*/
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Ox.encodeBase128 = function(num) {
|
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var str = '';
|
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while (num) {
|
||||
str = Ox.char(num & 127) + str;
|
||||
num >>= 7;
|
||||
}
|
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return str;
|
||||
};
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/*@
|
||||
Ox.decodeBase128 <f> Decode a base128-encoded number
|
||||
> Ox.decodeBase128('foo')
|
||||
1685487
|
||||
@*/
|
||||
Ox.decodeBase128 = function(str) {
|
||||
return str.split('').reverse().reduce(function(p, v, i) {
|
||||
return p + (v.charCodeAt(0) << i * 7);
|
||||
}, 0);
|
||||
};
|
||||
|
||||
/*@
|
||||
Ox.encodeBase256 <f> Encode a number as base256
|
||||
> Ox.encodeBase256(6713199)
|
||||
'foo'
|
||||
@*/
|
||||
Ox.encodeBase256 = function(num) {
|
||||
var str = '';
|
||||
while (num) {
|
||||
str = Ox.char(num & 255) + str;
|
||||
num >>= 8;
|
||||
}
|
||||
return str;
|
||||
};
|
||||
|
||||
/*@
|
||||
Ox.decodeBase256 <f> Decode a base256-encoded number
|
||||
> Ox.decodeBase256('foo')
|
||||
6713199
|
||||
@*/
|
||||
Ox.decodeBase256 = function(str) {
|
||||
return str.split('').reverse().reduce(function(p, v, i) {
|
||||
return p + (v.charCodeAt(0) << i * 8);
|
||||
}, 0);
|
||||
};
|
||||
|
||||
/*@
|
||||
Ox.encodeDeflate <f> Encodes a string, using deflate
|
||||
Since PNGs are deflate-encoded, the <code>canvas</code> object's
|
||||
<code>toDataURL</code> method provides an efficient implementation.
|
||||
The string is encoded as UTF-8 and written to the RGB channels of a
|
||||
canvas element, then the PNG dataURL is decoded from base64, and some
|
||||
head, tail and chunk names are removed.
|
||||
(str) -> <s> The encoded string
|
||||
str <s> The string to be encoded
|
||||
# Test with: Ox.decodeDeflate(Ox.encodeDeflate('foo'), alert)
|
||||
@*/
|
||||
|
||||
Ox.encodeDeflate = function(str, callback) {
|
||||
// Make sure we can encode the full unicode range of characters.
|
||||
str = Ox.encodeUTF8(str);
|
||||
// We can only safely write to RGB, so we need 1 pixel for 3 bytes.
|
||||
// The string length may not be a multiple of 3, so we need to encode
|
||||
// the number of padding bytes (1 byte), the string, and non-0-bytes
|
||||
// as padding, so that the combined length becomes a multiple of 3.
|
||||
var len = 1 + str.length, c = Ox.canvas(Math.ceil(len / 3), 1),
|
||||
data, idat, pad = (3 - len % 3) % 3;
|
||||
str = Ox.char(pad) + str + Ox.repeat('\u00FF', pad);
|
||||
Ox.loop(c.data.length, function(i) {
|
||||
// Write character codes into RGB, and 255 into ALPHA
|
||||
c.data[i] = i % 4 < 3 ? str.charCodeAt(i - parseInt(i / 4)) : 255;
|
||||
});
|
||||
c.context.putImageData(c.imageData, 0, 0);
|
||||
// Get the PNG data from the data URL and decode it from base64.
|
||||
str = atob(c.canvas.toDataURL().split(',')[1]);
|
||||
// Discard bytes 0 to 15 (8 bytes PNG signature, 4 bytes IHDR length, 4
|
||||
// bytes IHDR name), keep bytes 16 to 19 (width), discard bytes 20 to 29
|
||||
// (4 bytes height, 5 bytes flags), keep bytes 29 to 32 (IHDR checksum),
|
||||
// keep the rest (IDAT chunks), discard the last 12 bytes (IEND chunk).
|
||||
data = str.slice(16, 20) + str.slice(29, 33);
|
||||
idat = str.slice(33, -45);
|
||||
while (idat) {
|
||||
// Each IDAT chunk is 4 bytes length, 4 bytes name, length bytes
|
||||
// data and 4 bytes checksum. We can discard the name parts.
|
||||
len = idat.slice(0, 4);
|
||||
data += len + idat.slice(8, 12 + (len = Ox.decodeBase256(len)));
|
||||
idat = idat.slice(12 + len);
|
||||
}
|
||||
callback && callback(data);
|
||||
return data;
|
||||
};
|
||||
|
||||
/*@
|
||||
Ox.decodeDeflate <f> Decodes an deflate-encoded string
|
||||
Since PNGs are deflate-encoded, the <code>canvas</code> object's
|
||||
<code>drawImage</code> method provides an efficient implementation. The
|
||||
string will be wrapped as a PNG dataURL, encoded as base64, and drawn
|
||||
onto a canvas element, then the RGB channels will be read, and the
|
||||
result will be decoded from UTF8.
|
||||
(str) -> <u> undefined
|
||||
str <s> The string to be decoded
|
||||
callback <f> Callback function
|
||||
str <s> The decoded string
|
||||
@*/
|
||||
|
||||
Ox.decodeDeflate = function(str, callback) {
|
||||
var image = new Image(),
|
||||
// PNG file signature and IHDR chunk
|
||||
data = '\u0089PNG\r\n\u001A\n\u0000\u0000\u0000\u000DIHDR'
|
||||
+ str.slice(0, 4) + '\u0000\u0000\u0000\u0001'
|
||||
+ '\u0008\u0006\u0000\u0000\u0000' + str.slice(4, 8),
|
||||
// IDAT chunks
|
||||
idat = str.slice(8), len;
|
||||
function error() {
|
||||
throw new RangeError('Deflate codec can\'t decode data.');
|
||||
}
|
||||
while (idat) {
|
||||
// Reinsert the IDAT chunk names
|
||||
len = idat.slice(0, 4);
|
||||
data += len + 'IDAT' + idat.slice(4, 8 + (len = Ox.decodeBase256(len)));
|
||||
idat = idat.slice(8 + len);
|
||||
}
|
||||
// IEND chunk
|
||||
data += '\u0000\u0000\u0000\u0000IEND\u00AE\u0042\u0060\u0082';
|
||||
// Unfortunately, we can't synchronously set the source of an image,
|
||||
// draw it onto a canvas, and read its data.
|
||||
image.onload = function() {
|
||||
str = Ox.toArray(Ox.canvas(image).data).map(function(v, i) {
|
||||
// Read one character per RGB byte, ignore ALPHA.
|
||||
return i % 4 < 3 ? Ox.char(v) : '';
|
||||
}).join('');
|
||||
try {
|
||||
// Parse the first byte as number of bytes to chop at the end,
|
||||
// and the rest, without these bytes, as an UTF8-encoded string.
|
||||
str = Ox.decodeUTF8(str.slice(1, -str.CharCodeAt(0)));
|
||||
} catch (e) {
|
||||
error();
|
||||
}
|
||||
callback(str);
|
||||
}
|
||||
image.onerror = error;
|
||||
image.src = 'data:image/png;base64,' + btoa(data);
|
||||
};
|
||||
|
||||
/*@
|
||||
Ox.encodeHTML <f> HTML-encodes a string
|
||||
> Ox.encodeHTML('\'<"&">\'')
|
||||
''<"&">''
|
||||
> Ox.encodeHTML('äbçdê')
|
||||
'äbçdê'
|
||||
@*/
|
||||
Ox.encodeHTML = function(str) {
|
||||
return Ox.map(str.toString(), function(v) {
|
||||
var code = v.charCodeAt(0);
|
||||
return code < 128
|
||||
? (v in Ox.HTML_ENTITIES ? Ox.HTML_ENTITIES[v] : v)
|
||||
: '&#x' + Ox.pad(code.toString(16).toUpperCase(), 4) + ';';
|
||||
});
|
||||
};
|
||||
|
||||
/*@
|
||||
Ox.decodeHTML <f> Decodes an HTML-encoded string
|
||||
> Ox.decodeHTML(''<"&">'')
|
||||
'\'<"&">\''
|
||||
> Ox.decodeHTML(''<"&">'')
|
||||
'\'<"&">\''
|
||||
> Ox.decodeHTML('äbçdê')
|
||||
'äbçdê'
|
||||
> Ox.decodeHTML('äbçdê')
|
||||
'äbçdê'
|
||||
> Ox.decodeHTML('<b>bold</b>')
|
||||
'<b>bold</b>'
|
||||
@*/
|
||||
Ox.decodeHTML = function(str) {
|
||||
// relies on dom, but shorter than using this:
|
||||
// http://www.w3.org/TR/html5/named-character-references.html
|
||||
return Ox.decodeHTMLEntities(Ox.element('<div>').html(str).html());
|
||||
};
|
||||
|
||||
Ox.encodeHTMLEntities = function(str) {
|
||||
return str.replace(
|
||||
new RegExp('(' + Object.keys(Ox.HTML_ENTITIES).join('|') + ')', 'g'),
|
||||
function(match) {
|
||||
return Ox.HTML_ENTITIES[match];
|
||||
}
|
||||
);
|
||||
};
|
||||
|
||||
Ox.decodeHTMLEntities = function(str) {
|
||||
return str.replace(
|
||||
new RegExp('(' + Ox.values(Ox.HTML_ENTITIES).join('|') + ')', 'g'),
|
||||
function(match) {
|
||||
return Ox.keyOf(Ox.HTML_ENTITIES, match);
|
||||
}
|
||||
);
|
||||
};
|
||||
|
||||
/*@
|
||||
Ox.encodeUTF8 <f> Encodes a string as UTF-8
|
||||
see http://en.wikipedia.org/wiki/UTF-8
|
||||
(string) -> <s> UTF-8 encoded string
|
||||
string <s> Any string
|
||||
> Ox.encodeUTF8("YES")
|
||||
"YES"
|
||||
> Ox.encodeUTF8("¥€$")
|
||||
"\u00C2\u00A5\u00E2\u0082\u00AC\u0024"
|
||||
@*/
|
||||
Ox.encodeUTF8 = function(str) {
|
||||
return Ox.map(str, function(chr) {
|
||||
var code = chr.charCodeAt(0),
|
||||
str = '';
|
||||
if (code < 128) {
|
||||
str = chr;
|
||||
} else if (code < 2048) {
|
||||
str = String.fromCharCode(code >> 6 | 192)
|
||||
+ String.fromCharCode(code & 63 | 128);
|
||||
} else {
|
||||
str = String.fromCharCode(code >> 12 | 224)
|
||||
+ String.fromCharCode(code >> 6 & 63 | 128)
|
||||
+ String.fromCharCode(code & 63 | 128);
|
||||
}
|
||||
return str;
|
||||
});
|
||||
};
|
||||
|
||||
/*@
|
||||
Ox.decodeUTF8 <f> Decodes an UTF-8-encoded string
|
||||
see http://en.wikipedia.org/wiki/UTF-8
|
||||
(utf8) -> <s> string
|
||||
utf8 <s> Any UTF-8-encoded string
|
||||
> Ox.decodeUTF8('YES')
|
||||
'YES'
|
||||
> Ox.decodeUTF8('\u00C2\u00A5\u00E2\u0082\u00AC\u0024')
|
||||
'¥€$'
|
||||
@*/
|
||||
Ox.decodeUTF8 = function(str) {
|
||||
var code,
|
||||
i = 0,
|
||||
len = str.length,
|
||||
ret = '';
|
||||
while (i < len) {
|
||||
code = Ox.range(3).map(function(o) {
|
||||
return str.charCodeAt(i + o);
|
||||
});
|
||||
if (code[0] <= 128) {
|
||||
ret += str[i];
|
||||
i++;
|
||||
} else if (
|
||||
code[0] >= 192 && code[0] < 240
|
||||
&& i < len - (code[0] < 224 ? 1 : 2)
|
||||
) {
|
||||
if (code[1] >= 128 && code[1] < 192) {
|
||||
if (code[0] < 224) {
|
||||
ret += String.fromCharCode(
|
||||
(code[0] & 31) << 6 | code[1] & 63
|
||||
);
|
||||
i += 2;
|
||||
} else if (code[2] >= 128 && code[2] < 192) {
|
||||
ret += String.fromCharCode(
|
||||
(code[0] & 15) << 12 | (code[1] & 63) << 6
|
||||
| code[2] & 63
|
||||
);
|
||||
i += 3;
|
||||
} else {
|
||||
throwUTF8Error(code[2], i + 2);
|
||||
}
|
||||
while (i < length) {
|
||||
code = [
|
||||
string.charCodeAt(i),
|
||||
string.charCodeAt(i + 1),
|
||||
string.charCodeAt(i + 2)
|
||||
];
|
||||
if (code[0] <= 128) {
|
||||
ret += string[i];
|
||||
i++;
|
||||
} else if (
|
||||
code[0] >= 192 && code[0] < 240
|
||||
&& i < length - (code[0] < 224 ? 1 : 2)
|
||||
) {
|
||||
if (code[1] >= 128 && code[1] < 192) {
|
||||
if (code[0] < 224) {
|
||||
ret += String.fromCharCode(
|
||||
(code[0] & 31) << 6 | code[1] & 63
|
||||
);
|
||||
i += 2;
|
||||
} else if (code[2] >= 128 && code[2] < 192) {
|
||||
ret += String.fromCharCode(
|
||||
(code[0] & 15) << 12 | (code[1] & 63) << 6
|
||||
| code[2] & 63
|
||||
);
|
||||
i += 3;
|
||||
} else {
|
||||
throwUTF8Error(code[1], i + 1);
|
||||
error(code[2], i + 2);
|
||||
}
|
||||
} else {
|
||||
throwUTF8Error(code[0], i);
|
||||
error(code[1], i + 1);
|
||||
}
|
||||
} else {
|
||||
error(code[0], i);
|
||||
}
|
||||
return ret;
|
||||
};
|
||||
|
||||
})();
|
||||
}
|
||||
return ret;
|
||||
};
|
||||
|
|
|
|||
Loading…
Reference in a new issue