/* 
 *   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 = '\n\
<div data-role="page" class="page" id="page-vplan-{ID}" data-prefetch>\n\
    <div data-role="header">\n\
        <h1>WvS VPlan | Vertretungen</h1>\n\
    </div>\n\
    <div role="main" class="ui-content" id="pdf-{ID}" data-plan-url="">\n\
    </div>\n\
</div>\n\
';

function renderPage(div, pdf, pageNumber, callback){
    pdf.getPage(pageNumber).then(function(page){
        var scale = 1;
        var viewport = page.getViewport(scale);

        var pageDisplayWidth = viewport.width;
        var pageDisplayHeight = viewport.height;

        var pageDivHolder = document.createElement('div');
/*        pageDivHolder.className = 'pdfpage';
        pageDivHolder.style.width = pageDisplayWidth + 'px';
        pageDivHolder.style.height = pageDisplayWidth + 'px';
*/
        var canvas = document.createElement('canvas');
        canvas.className = 'pdfcanvas';
        var context = canvas.getContext('2d');
        canvas.width = pageDisplayWidth;
        canvas.height = pageDisplayHeight;

        pageDivHolder.appendChild(canvas);
        div.appendChild(pageDivHolder);

        var renderContext = {
            canvasContext: context,
            viewport: viewport
        };
        page.render(renderContext).promise.then(callback);
    });
}

function render_pdf(viewerstr){
    console.log("Rendere PDF: " + $(viewerstr).attr('data-plan-url') + " (" + viewerstr + ")");

    PDFJS.getDocument($(viewerstr).attr('data-plan-url')).then(function(pdf){
        var viewer = document.getElementById(viewerstr.replace(/#/, ''));
        var pageNumber = 1;
        renderPage(viewer, pdf, pageNumber++, function pageRenderingComplete(){
            if(pageNumber > pdf.numPages){
                return;
            }
            renderPage(viewer, pdf, pageNumber++, pageRenderingComplete);
        });
    });
}

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

function download_pdf(link, id){
    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());
                                $('#pdf-' + id).attr('data-plan-url', theFile.toURL());

                                if(location.href.indexOf("page-") == -1){
                                    location.href = "#page-vplan-" + id;
                                }
                            },
                            function(error){
                                console.log("Fehler: " + error.source + " - "+ error.target + " - " + error.code);
                            }
                            );
                    },
                    fail);
            },
            fail);
}

function get_plan(link, id){
    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, id);
    });

    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;\\)", "g");
        var link;

        // TODO keine result.match: Login fehlerhaft
        //
        // Pages für Vertretungsplände erstellen und pageshow-Events festlegen
        
        var resultl = result.match(plans_re).length;

        for(j = 0; j < resultl; j++){
            new_html = page_html.replace(/{ID}/g, j);
            
            $('#loginpage').after(new_html);

            if(j + 1 < resultl){
                $('#page-vplan-' + j).on('swipeleft', function(event){
                    console.log("Wisch links");
                    location.href = "#page-vplan-" + (parseInt($('.ui-page-active').attr('id').match(/\d+/)[0]) + 1);
                });
            }

            if(j - 1 >= 0){
                $('#page-vplan-' + j).on('swiperight', function(event){
                    console.log("Wisch rechts");
                    location.href = "#page-vplan-" + (parseInt($('.ui-page-active').attr('id').match(/\d+/)[0]) - 1);
                });
            }

            console.log('Html hinzugefügt zu: ' + j);

            $('#page-vplan-' + j).on('pageshow', function(event){
                render_pdf($('.ui-page-active').attr('id').replace(/page-vplan/, '#pdf'));
            });
        }
        
        j = 0;

        while((link = plans_re.exec(result)) !== null){
            console.log('suche Plan ' + link[1]);
            get_plan(link[1], j++);
        }

        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);
    }
};