/* 
 *   Copyright (C) 2014
 *   This file is part of WvS VPlan.
 *
 *   WvS VPlan is free software: you can redistribute it and/or modify
 *   it under the terms of the GNU Affero General Public License as published by
 *   the Free Software Foundation, either version 3 of the License, or
 *   (at your option) any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU Affero General Public License for more details.
 *
 *   You should have received a copy of the GNU Affero General Public License
 *   along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

var page_html = '\
<div data-role="page" class="page" id="page-{ID}" data-prefetch>\
    <div data-role="header">\
        <h1>WvS VPlan | Vertretungen</h1>\
    </div>\
    <div role="main" class="ui-content">\
        <canvas id="canvas-{ID}" style="border:1px solid black;"/>\
    </div>\
</div>\
';

function show_pdf(url, filename){
    name = encodeURIComponent(filename.replace(".pdf", ""));

    console.log("Download fertig, zeige PDF " + name);

    $("#loginpage").after(page_html.replace(/{ID}/g, name));
    location.href = "#page-" + name;

    PDFJS.getDocument(url).then(function(pdf){
        pdf.getPage(1).then(function(page){
            var scale = 1.5;
            var viewport = page.getViewport(scale);
            var canvas = document.getElementById("canvas-" + name);
            var context = canvas.getContext('2d');

            canvas.height = viewport.height;
            canvas.width = viewport.width;

            var renderContext = {
                canvasContext: context,
                viewport: viewport
            };

            page.render(renderContext);
        });
    });
}

function fail(text){
    alert("Etwas ist schiefgelaufen: " + text.toString());
}

function download_pdf(link){
    var filename = link.substring(link.lastIndexOf('/') + 1);

    window.requestFileSystem(
            LocalFileSystem.PERSISTENT, 0,
            function onFileSystemSuccess(fileSystem){
                fileSystem.root.getFile(
                    filename, {create: true, exclusive: false},
                    function gotFileEntry(fileEntry){
                        var sPath = "/storage/sdcard0" + fileEntry.fullPath; // !!! TODO Unterstützung anderer Geräte
                        console.log("Pfad: " + sPath);
                        var fileTransfer = new FileTransfer();
                        fileEntry.remove();

                        fileTransfer.download(
                            link,
                            sPath,
                            function(theFile){
                                console.log("Download fertig: " + theFile.toURL());
                                show_pdf(theFile.toURL(), filename);
                            },
                            function(error){
                                console.log("Fehler: " + error.source + " - "+ error.target + " - " + error.code);
                            }
                            );
                    },
                    fail);
            },
            fail);
}

function get_plan(link){
    var request = $.ajax({
        type: "GET",
        url: link
    });

    request.done(function(result){
        var pdf_re = new RegExp("(http://***REMOVED***\\.de/moodle/pluginfile\\.php/\\d+/mod_resource/content/\\d+.*?\\.pdf)");
        var pdflink = pdf_re.exec(result)[1];

        console.log('Plan gefunden: ' + pdflink);

        download_pdf(pdflink);
    });

    request.fail(function(jqXHR, textStatus){
        alert("Etwas ist schiefgelaufen: " + textStatus);
    });
}

function get_overview(link){
    var request = $.ajax({
        type: "GET",
        url: link
    });

    request.done(function(result){
        var plans_re = new RegExp("window\\.open\\(&#039;(http://***REMOVED***\\.de/moodle/mod/resource/view\\.php\\?id=\\d+)&amp;redirect=1&#039;\\)");
        var links = plans_re.exec(result);

        for(var i = 1; i < links.length; i += 2){
            console.log('suche Plan ' + links[i]);
            get_plan(links[i]);
        }

        console.log('Übersichts-Request erfolgreich');
    });

    request.fail(function(jqXHR, textStatus){
        alert("Etwas ist schiefgelaufen: " + textStatus);
    });
}

function login(){
    $.mobile.loading("show", {
        text: "Lade...",
        textVisible: true,
        theme: "b",
    });

    var username = encodeURIComponent($("#username").val());
    var password = encodeURIComponent($("#password").val());
    var params = "username=" + username + "&password=" + password;

    var request = $.ajax({
        type: "POST",
        url: "https://***REMOVED***/moodle/login/index.php",
        data: {username: username, password: password}
    });
    request.done(function(result){
        var vertretungs_re = new RegExp("title=\"Vertretungsplan\" href=\"(http://***REMOVED***\\.de/moodle/course/view\\.php\\?id=\\d+)");
        var link = vertretungs_re.exec(result)[1];

        console.log('Login-Request erfolgreich: ' + link);

        get_overview(link);
    });

    request.fail(function(jqXHR, textStatus){
        alert("Etwas ist schiefgelaufen: " + textStatus);
    });
}

var app = {
    // Application Constructor
    initialize: function() {
        this.bindEvents();
    },
    // Bind Event Listeners
    //
    // Bind any events that are required on startup. Common events are:
    // 'load', 'deviceready', 'offline', and 'online'.
    bindEvents: function() {
        document.addEventListener('deviceready', this.onDeviceReady, false);
    },
    // deviceready Event Handler
    //
    // The scope of 'this' is the event. In order to call the 'receivedEvent'
    // function, we must explicity call 'app.receivedEvent(...);'
    onDeviceReady: function() {
        app.receivedEvent('deviceready');
    },
    // Update DOM on a Received Event
    receivedEvent: function(id) {
        /* var parentElement = document.getElementById(id);
        var listeningElement = parentElement.querySelector('.listening');
        var receivedElement = parentElement.querySelector('.received');

        listeningElement.setAttribute('style', 'display:none;');
        receivedElement.setAttribute('style', 'display:block;');

        */
        console.log('Received Event: ' + id);
    }
};