window.ls.filter
    .add('gravatar', function ($value, element) {
        if(!$value) {
            return '';
        }

        // MD5 (Message-Digest Algorithm) by WebToolkit
        let MD5     = function(s){function L(k,d){return(k<<d)|(k>>>(32-d))}function K(G,k){let I,d,F,H,x;F=(G&2147483648);H=(k&2147483648);I=(G&1073741824);d=(k&1073741824);x=(G&1073741823)+(k&1073741823);if(I&d){return(x^2147483648^F^H)}if(I|d){if(x&1073741824){return(x^3221225472^F^H)}else{return(x^1073741824^F^H)}}else{return(x^F^H)}}function r(d,F,k){return(d&F)|((~d)&k)}function q(d,F,k){return(d&k)|(F&(~k))}function p(d,F,k){return(d^F^k)}function n(d,F,k){return(F^(d|(~k)))}function u(G,F,aa,Z,k,H,I){G=K(G,K(K(r(F,aa,Z),k),I));return K(L(G,H),F)}function f(G,F,aa,Z,k,H,I){G=K(G,K(K(q(F,aa,Z),k),I));return K(L(G,H),F)}function D(G,F,aa,Z,k,H,I){G=K(G,K(K(p(F,aa,Z),k),I));return K(L(G,H),F)}function t(G,F,aa,Z,k,H,I){G=K(G,K(K(n(F,aa,Z),k),I));return K(L(G,H),F)}function e(G){let Z;let F=G.length;let x=F+8;let k=(x-(x%64))/64;let I=(k+1)*16;let aa=Array(I-1);let d=0;let H=0;while(H<F){Z=(H-(H%4))/4;d=(H%4)*8;aa[Z]=(aa[Z]|(G.charCodeAt(H)<<d));H++}Z=(H-(H%4))/4;d=(H%4)*8;aa[Z]=aa[Z]|(128<<d);aa[I-2]=F<<3;aa[I-1]=F>>>29;return aa}function B(x){let k="",F="",G,d;for(d=0;d<=3;d++){G=(x>>>(d*8))&255;F="0"+G.toString(16);k=k+F.substr(F.length-2,2)}return k}function J(k){k=k.replace(/rn/g,"n");let d="";for(let F=0;F<k.length;F++){let x=k.charCodeAt(F);if(x<128){d+=String.fromCharCode(x)}else{if((x>127)&&(x<2048)){d+=String.fromCharCode((x>>6)|192);d+=String.fromCharCode((x&63)|128)}else{d+=String.fromCharCode((x>>12)|224);d+=String.fromCharCode(((x>>6)&63)|128);d+=String.fromCharCode((x&63)|128)}}}return d}let C=Array();let P,h,E,v,g,Y,X,W,V;let S=7,Q=12,N=17,M=22;let A=5,z=9,y=14,w=20;let o=4,m=11,l=16,j=23;let U=6,T=10,R=15,O=21;s=J(s);C=e(s);Y=1732584193;X=4023233417;W=2562383102;V=271733878;for(P=0;P<C.length;P+=16){h=Y;E=X;v=W;g=V;Y=u(Y,X,W,V,C[P+0],S,3614090360);V=u(V,Y,X,W,C[P+1],Q,3905402710);W=u(W,V,Y,X,C[P+2],N,606105819);X=u(X,W,V,Y,C[P+3],M,3250441966);Y=u(Y,X,W,V,C[P+4],S,4118548399);V=u(V,Y,X,W,C[P+5],Q,1200080426);W=u(W,V,Y,X,C[P+6],N,2821735955);X=u(X,W,V,Y,C[P+7],M,4249261313);Y=u(Y,X,W,V,C[P+8],S,1770035416);V=u(V,Y,X,W,C[P+9],Q,2336552879);W=u(W,V,Y,X,C[P+10],N,4294925233);X=u(X,W,V,Y,C[P+11],M,2304563134);Y=u(Y,X,W,V,C[P+12],S,1804603682);V=u(V,Y,X,W,C[P+13],Q,4254626195);W=u(W,V,Y,X,C[P+14],N,2792965006);X=u(X,W,V,Y,C[P+15],M,1236535329);Y=f(Y,X,W,V,C[P+1],A,4129170786);V=f(V,Y,X,W,C[P+6],z,3225465664);W=f(W,V,Y,X,C[P+11],y,643717713);X=f(X,W,V,Y,C[P+0],w,3921069994);Y=f(Y,X,W,V,C[P+5],A,3593408605);V=f(V,Y,X,W,C[P+10],z,38016083);W=f(W,V,Y,X,C[P+15],y,3634488961);X=f(X,W,V,Y,C[P+4],w,3889429448);Y=f(Y,X,W,V,C[P+9],A,568446438);V=f(V,Y,X,W,C[P+14],z,3275163606);W=f(W,V,Y,X,C[P+3],y,4107603335);X=f(X,W,V,Y,C[P+8],w,1163531501);Y=f(Y,X,W,V,C[P+13],A,2850285829);V=f(V,Y,X,W,C[P+2],z,4243563512);W=f(W,V,Y,X,C[P+7],y,1735328473);X=f(X,W,V,Y,C[P+12],w,2368359562);Y=D(Y,X,W,V,C[P+5],o,4294588738);V=D(V,Y,X,W,C[P+8],m,2272392833);W=D(W,V,Y,X,C[P+11],l,1839030562);X=D(X,W,V,Y,C[P+14],j,4259657740);Y=D(Y,X,W,V,C[P+1],o,2763975236);V=D(V,Y,X,W,C[P+4],m,1272893353);W=D(W,V,Y,X,C[P+7],l,4139469664);X=D(X,W,V,Y,C[P+10],j,3200236656);Y=D(Y,X,W,V,C[P+13],o,681279174);V=D(V,Y,X,W,C[P+0],m,3936430074);W=D(W,V,Y,X,C[P+3],l,3572445317);X=D(X,W,V,Y,C[P+6],j,76029189);Y=D(Y,X,W,V,C[P+9],o,3654602809);V=D(V,Y,X,W,C[P+12],m,3873151461);W=D(W,V,Y,X,C[P+15],l,530742520);X=D(X,W,V,Y,C[P+2],j,3299628645);Y=t(Y,X,W,V,C[P+0],U,4096336452);V=t(V,Y,X,W,C[P+7],T,1126891415);W=t(W,V,Y,X,C[P+14],R,2878612391);X=t(X,W,V,Y,C[P+5],O,4237533241);Y=t(Y,X,W,V,C[P+12],U,1700485571);V=t(V,Y,X,W,C[P+3],T,2399980690);W=t(W,V,Y,X,C[P+10],R,4293915773);X=t(X,W,V,Y,C[P+1],O,2240044497);Y=t(Y,X,W,V,C[P+8],U,1873313359);V=t(V,Y,X,W,C[P+15],T,4264355552);W=t(W,V,Y,X,C[P+6],R,2734768916);X=t(X,W,V,Y,C[P+13],O,1309151649);Y=t(Y,X,W,V,C[P+4],U,4149444226);V=t(V,Y,X,W,C[P+11],T,3174756917);W=t(W,V,Y,X,C[P+2],R,718787259);X=t(X,W,V,Y,C[P+9],O,3951481745);Y=K(Y,h);X=K(X,E);W=K(W,v);V=K(V,g)}let i=B(Y)+B(X)+B(W)+B(V);return i.toLowerCase()};
        let size    = element.dataset['size'] || 80;
        let email = $value.email || $value || '';
        let name = $value.name || $value || '';
        let theme = name.split('').map(char => char.charCodeAt(0)).reduce((a, b) => a + b, 0).toString();
        let themes = [
            { color: '27005e', background: 'e1d2f6' }, // VIOLET
            { color: '5e2700', background: 'f3d9c6' }, // ORANGE
            { color: '006128', background: 'c9f3c6' }, // GREEN
            { color: '580061', background: 'f2d1f5' }, // FUSCHIA
            { color: '00365d', background: 'c6e1f3' }, // BLUE
            { color: '00075c', background: 'd2d5f6' }, // INDIGO
            { color: '610038', background: 'f5d1e6' }, // PINK
            { color: '386100', background: 'dcf1bd' }, // LIME
            { color: '615800', background: 'f1ecba' }, // YELLOW
            { color: '610008', background: 'f6d2d5' }, // RED
        ];

        name = name.split(' ').map(function (n) {
            if(!isNaN(parseFloat(n)) && isFinite(n)) {
                return '';
            }

            return n[0];
        }).join('') || '--';
        
        let background = themes[theme[theme.length -1]]['background'];
        let color = themes[theme[theme.length -1]]['color'];

        let def = 'https://ui-avatars.com/api/' + encodeURIComponent(name) + '/' + size + '/' + encodeURIComponent(background) + '/' + encodeURIComponent(color);

        return '//www.gravatar.com/avatar/' + MD5(email) + '.jpg?s=' + size + '&d=' + encodeURIComponent(def);
    })
    .add('selectedCollection', function ($value, router) {
        return ($value === router.params.collectionId) ? 'selected' : '';
    })
    .add('selectedDocument', function ($value, router) {
        return ($value === router.params.documentId) ? 'selected' : '';
    })
    .add('localeString', function ($value) {
        $value = parseInt($value);
        return (!Number.isNaN($value)) ? $value.toLocaleString() : '';
    })
    .add('date', function ($value, date) {
        return date.format('Y-m-d', $value);
    })
    .add('date-time', function ($value, date) {
        return date.format('Y-m-d H:i', $value);
    })
    .add('date-text', function ($value, date) {
        return date.format('d M Y', $value);
    })
    .add('ms2hum', function ($value) {
        let temp = $value;
        const years = Math.floor( temp / 31536000 ),
            days = Math.floor( ( temp %= 31536000 ) / 86400 ),
            hours = Math.floor( ( temp %= 86400 ) / 3600 ),
            minutes = Math.floor( ( temp %= 3600 ) / 60 ),
            seconds = temp % 60;

        if ( days || hours || seconds || minutes ) {
            return ( years ? years + "y " : "" ) +
                ( days ? days + "d " : "" ) +
                ( hours ? hours + "h " : ""  ) +
                ( minutes ? minutes + "m " : "" ) +
                Number.parseFloat( seconds ).toFixed(0) + "s";
        }

        return "< 1s";
    })
    .add('markdown', function ($value, markdown) {
        return markdown.render($value);
    })
    .add('pageCurrent', function ($value, env) {
        return Math.ceil(parseInt($value || 0) / env.PAGING_LIMIT) + 1;
    })
    .add('pageTotal', function ($value, env) {
        let total = Math.ceil(parseInt($value || 0) / env.PAGING_LIMIT);
        return (total) ? total : 1;
    })
    .add('humanFileSize', function ($value) {
        if (!$value) {
            return 0;
        }

        let thresh = 1000;

        if (Math.abs($value) < thresh) {
            return $value + ' B';
        }

        let units = ['kB','MB','GB','TB','PB','EB','ZB','YB'];
        let u = -1;

        do {
            $value /= thresh;
            ++u;
        } while (Math.abs($value) >= thresh && u < units.length - 1);

        return $value.toFixed(1) + '<span class="text-size-small unit">' + units[u] + '</span>';
    })
    .add('statsTotal', function ($value) {
        if(!$value) {
            return 0;
        }

        $value = abbreviate($value, 1, false, false);

        return ($value === '0') ? 'N/A' : $value;
    });

function abbreviate(number, maxPlaces, forcePlaces, forceLetter) {
    number = Number(number);
    forceLetter = forceLetter || false;
    if(forceLetter !== false) {
        return annotate(number, maxPlaces, forcePlaces, forceLetter);
    }
    let abbr;
    if(number >= 1e12) {
        abbr = 'T';
    }
    else if(number >= 1e9) {
        abbr = 'B';
    }
    else if(number >= 1e6) {
        abbr = 'M';
    }
    else if(number >= 1e3) {
        abbr = 'K';
    }
    else {
        abbr = '';
    }
    return annotate(number, maxPlaces, forcePlaces, abbr);
}

function annotate(number, maxPlaces, forcePlaces, abbr) {
    // set places to false to not round
    let rounded = 0;
    switch(abbr) {
        case 'T':
            rounded = number / 1e12;
            break;
        case 'B':
            rounded = number / 1e9;
            break;
        case 'M':
            rounded = number / 1e6;
            break;
        case 'K':
            rounded = number / 1e3;
            break;
        case '':
            rounded = number;
            break
    }
    if(maxPlaces !== false) {
        let test = new RegExp('\\.\\d{' + (maxPlaces + 1) + ',}$')
        if(test.test(('' + rounded))) {
            rounded = rounded.toFixed(maxPlaces)
        }
    }
    if(forcePlaces !== false) {
        rounded = Number(rounded).toFixed(forcePlaces)
    }
    return rounded + abbr
}