// vim:set sw=4 ts=4 sts=4 ft=javascript expandtab:

/*

 * Return the deciphering key stored in anchor part of the URL

 * Stolen from https://github.com/sebsauvage/ZeroBin/blob/master/js/zerobin.js

 */

function pageKey() {

    var key = window.location.hash.substring(1);  // Get key

    // Some stupid web 2.0 services and redirectors add data AFTER the anchor

    // (such as &utm_source=...).

    // We will strip any additional data.

    // First, strip everything after the equal sign (=) which signals end of base64 string.

    i = key.indexOf('='); if (i>-1) { key = key.substring(0,i+1); }

    // If the equal sign was not present, some parameters may remain:

    i = key.indexOf('&';; if (i>-1) { key = key.substring(0,i); }

    // Then add trailing equal sign if it's missing

    if (key.charAt(key.length-1)!=='=') key+='=';

    return key;

}

function base64ToArrayBuffer(base64) {

    var binary_string =  window.atob(base64);

    var len = binary_string.length;

    var bytes = new Uint8Array( len );

    for (var i = 0; i < len; i++)        {

        bytes[i] = binary_string.charCodeAt(i);

    }

    return bytes.buffer;

}

// Something's wring

function addAlert(msg) {

    $('#please-wait').remove();

    var pbd = $('.file-progress');

    pbd.attr('role', 'alert');

    pbd.removeClass('progress');

    pbd.html(['
',

                  '
',

                      '', msg, '',

                  '',

              ''].join(''));

}

// Spawn WebSocket

function spawnWebsocket(pa) {

    var ws       = new WebSocket(ws_url);

    ws.onopen    = function() {

        console.log('Connection is established!');

        var l    = $('#loading');

        l.html(i18n.loading.replace(/XX1/, (pa + 1)));

        if ($('#file_pwd').length === 1) {

            window.ws.send('{"part":'+pa+', "file_pwd": "'+$('#file_pwd').val()+'"}');

        } else {

            window.ws.send('{"part":'+pa+'}');

        }

    };

    ws.onclose   = function() {

        console.log('Connection is closed');

        if (!window.completed) {

            console.log('Connection closed. Retrying to get slice '+pa);

            window.ws = spawnWebsocket(pa);

        }

    }

    ws.onmessage = function(e) {

        var res  = e.data.split('XXMOJOXX');

        var json = res.shift();

        var data = JSON.parse(json);

        if (data.msg !== undefined) {

            addAlert(data.msg);

            console.log(data.msg);

            if ($('#file_pwd').length === 1) {

                $('.file-abort').addClass('hide');

            }

            window.onbeforeunload = null;

        } else {

            console.log('Getting slice '+(data.part + 1)+' of '+data.total);

            var slice   = JSON.parse(res.shift());

            var percent = Math.round(100 * (data.part + 1)/data.total);

            var pb      = $('#pb');

            pb.css('width', percent+'%');

            pb.attr('aria-valuenow', percent);

            $('#pbt').html(percent+'%');

            try {

                var b64 = sjcl.decrypt(window.key, slice);

                window.a[data.part] = base64ToArrayBuffer(b64);

                if (data.part + 1 === data.total) {

                    var blob = new Blob(a, {type: data.type});

                    $('#please-wait').remove();

                    $('#loading').remove();

                    var pbd  = $('#pbd');

                    pbd.attr('class', 'center-align');

                    // IE & Edge fix for downloading blob files, gives option to save or open the file when the link is opened.

                    if (window.navigator && window.navigator.msSaveOrOpenBlob) {

                        var fileName = escapeHtml(data.name);

                        window.navigator.msSaveOrOpenBlob(blob, fileName);

                    } else {

                        var blobURL   = URL.createObjectURL(blob);

                    }

                    var innerHTML = ['
', i18n.download, '
'];

                    if (data.type.match(/^image\//) !== null) {

                        innerHTML.push('');

                    } else if (data.type.match(/^video\//) !== null) {

                        innerHTML.push('<video class="responsive-video" controls>',

                                           '<source src="', blobURL, '" type="', data.type, '">',

                                       '</video>');

                    } else if (data.type.match(/^audio\//) !== null) {

                        innerHTML.push('<audio class="responsive-video" controls>',

                                           '<source src="', blobURL, '" type="', data.type, '">',

                                       '</audio>');

                    }

                    pbd.html(innerHTML.join(''));

                    if ($('#file_pwd').length === 1) {

                        window.ws.send('{"ended":true, "file_pwd": "'+$('#file_pwd').val()+'"}');

                    } else {

                        window.ws.send('{"ended":true}');

                    }

                    window.onbeforeunload = null;

                    window.completed = true;

                    $('#abort').remove();

                } else {

                    var l = $('#loading');

                    l.html(i18n.loading.replace(/XX1/, (data.part + 1)));

                    if (ws.readyState === 3) {

                        window.ws = spawnWebsocket(data.part + 1);

                    } else {

                        window.ws.onclose = function() {

                            console.log('Connection is closed');

                            if (!window.completed) {

                                console.log('Connection closed. Retrying to get slice '+(data.part + 1));

                                window.ws = spawnWebsocket(data.part + 1);

                            }

                        }

                        window.ws.onerror = function() {

                            console.log('Error. Retrying to get slice '+(data.part + 1));

                            window.ws = spawnWebsocket(data.part + 1);

                        };

                        if ($('#file_pwd').length === 1) {

                            window.ws.send('{"part":'+(data.part + 1)+', "file_pwd": "'+$('#file_pwd').val()+'"}');

                        } else {

                            window.ws.send('{"part":'+(data.part + 1)+'}');

                        }

                    }

                }

            } catch(err) {

                if (err.message === 'ccm: tag doesn\'t match') {

                    addAlert(i18n.badkey);

                } else {

                    addAlert(err.message);

                }

                window.onbeforeunload = null;

            }

        }

    }

    ws.onerror = function() {

        console.log('Error. Retrying to get slice '+pa);

        window.ws = spawnWebsocket(pa);

    }

    return ws;

}

// When it's ready

$(document).ready(function(){

    $('#abort').click(function() {

        window.ws.onclose = function() {};

        window.ws.close();

        $('#please-wait, #loading, #pbd, #abort').remove();

        $('#filesize').parent().append('
'+i18n.aborted1+'
'+i18n.aborted2+'
');

        window.onbeforeunload = null;

    });

    $('#filesize').html(filesize($('#filesize').attr('data-filesize'), {base: 10}));

    window.a         = new Array();

    window.key       = pageKey();

    window.completed = false;

    if (key !== '=') {

        var go = true;

        if ($('#file_pwd').length === 1) {

            go = false;

            $('#go').click(function() {

                $('.file-progress, .file-abort').removeClass('hide');

                $('#file_pwd').parent().parent().addClass('hide');

                // Set websocket

                window.ws = spawnWebsocket(0);

                // Prevent exiting page before full download

                window.onbeforeunload = confirmExit;

            });

        }

        if (go) {

            // Set websocket

            window.ws = spawnWebsocket(0);

            // Prevent exiting page before full download

            window.onbeforeunload = confirmExit;

        }

    } else {

        addAlert(i18n.nokey);

    }

});