SandboXP

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// -------------------------------------------------
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// ------------------ UTF8 Helpers -----------------
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// -------------------------------------------------
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"use strict";
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var UTF8 = {};
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/** @constructor */
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function UTF8StreamToUnicode() {
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    this.stream = new Uint8Array(5);
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    this.ofs = 0;
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    this.Put = function(key) {
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        this.stream[this.ofs] = key;
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        this.ofs++;
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        switch(this.ofs) {
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            case 1:
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                if (this.stream[0] < 128) {
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                    this.ofs = 0;
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                    return this.stream[0];
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                }
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                break;
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            case 2:
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                if ((this.stream[0]&0xE0) == 0xC0)
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                if ((this.stream[1]&0xC0) == 0x80) {
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                    this.ofs = 0;
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                    return ((this.stream[0]&0x1F)<<6) | (this.stream[1]&0x3F);
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                }
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                break;
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            case 3:
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                break;
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            case 4:
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                break;
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            default:
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                return -1;
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                //this.ofs = 0;
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                //break;
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        }
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        return -1;
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    };
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}
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function UnicodeToUTF8Stream(key)
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{
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        if (key < 0x80)  return [key];
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        if (key < 0x800) return [0xC0|((key>>6)&0x1F), 0x80|(key&0x3F)];
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}
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UTF8.UTF8Length = function(s)
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{
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    var length = 0;
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    for(var i=0; i<s.length; i++) {
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        var c = s.charCodeAt(i);
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        length += c<128?1:2;
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    }
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    return length;
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};
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