var pako;

(function (global) {
    'use strict';
    
    if (typeof module !== 'undefined' && module.exports) {
        module.exports  = new ZipProto();
        pako            = require('pako');
    } else {
        global.zipio    = new ZipProto();
    }
    
    function ZipProto() {
       var UTF8 = new UTF8Proto();
       
        function zipio(str, callback) {
            var buf, deflate, result,
                isArrayBuffer = type(str) === 'arrayBuffer';
            
            if (!callback)
                throw(Error('callback could not be empty!'));
            
            if (isArrayBuffer)
                buf     = str;
            else
                buf     = utf8AbFromStr(str);
            
            deflate = new pako.Deflate({
                gzip:true
            });
            
            deflate.push(buf, true);
            
            if (!deflate.error)
                result = deflate.result.buffer;
            
            callback(deflate.error, result);
        }
        
        function utf8AbFromStr(str) {
            var i,
                strUtf8 = UTF8.unescape(encodeURIComponent(str)),
                n       = strUtf8.length,
                arr     = new Uint8Array(n);
            
            for (i = 0; i < n; i++)
                arr[i] = strUtf8.charCodeAt(i);
            
            return arr;
        }
        
        function type(variable) {
            var regExp      = new RegExp('\\s([a-zA-Z]+)'),
                str         = {}.toString.call(variable),
                typeBig     = str.match(regExp)[1],
                result      = typeBig.toLowerCase();
            
            return result;
        }
        
        return zipio;
    }
   
    function UTF8Proto() {
        /*jshint nonstandard:true */
        var isUnescape  = typeof unescape === 'function',
            func        = isUnescape ? unescape : decode;
        
        this.unescape   = func;
        
         /* 
         * unescape polyfill
         * http://unixpapa.com/js/querystring.html
         */
         
        function decode(s) {
            s = s.replace(/%([EF][0-9A-F])%([89AB][0-9A-F])%([89AB][0-9A-F])/gi, ef)
                 .replace(/%([CD][0-9A-F])%([89AB][0-9A-F])/gi, cd)
                 .replace(/%([0-7][0-9A-F])/gi, o7);
            
            return s;
            
            function o7(code, hex) {
                return String.fromCharCode(parseInt(hex,16));
            }
                
            function ef(code, hex1, hex2, hex3) {
                var n, n3,
                    n1 = parseInt(hex1,16) - 0xE0,
                    n2 = parseInt(hex2,16) - 0x80;
                
                if (n1 === 0 && n2 < 32)
                    return code;
                
                n3  = parseInt(hex3,16)-0x80;
                n   = (n1<<12) + (n2<<6) + n3;
                
                if (n > 0xFFFF)
                    return code;
                
                return String.fromCharCode(n);
            }
            
            function cd(code, hex1, hex2) {
                var n1, n2;
                
                n1 = parseInt(hex1,16) - 0xC0;
                
                if (n1 < 2)
                    return code;
                
                n2 = parseInt(hex2,16) - 0x80;
                
                return String.fromCharCode((n1<<6) + n2);
            }
        }
   }
    
})(this);