'use strict';

(function() {

    var animationInterval,
        enableDebugMode = getLocalStorage('oml.enableDebugMode'),
        omlVersion = getOMLVersion(),
        oxjsPath = '/static/oxjs/' + (enableDebugMode ? 'dev' : 'min'),
        terminal,
        theme = getLocalStorage('Ox.theme')
            && JSON.parse(localStorage['Ox.theme'])
            || 'oxlight';

    loadImages(function(images) {
        loadScreen(images);
        loadOxJS(loadOML);
    });

    function getLocalStorage(key) {
        try {
            return localStorage[key];
        } catch(e) {}
    }

    function getOMLVersion() {
        var i, path, scripts = document.getElementsByTagName('script');
        for (i = 0; i < scripts.length; i++) {
            if(/oml.update.js/.test(scripts[i].src)) {
                return scripts[i].src.replace(/.*\?/, '');
            }
        }
    }

    function loadImages(callback) {
        var images = {};
        images.logo = document.createElement('img');
        images.logo.onload = function() {
            images.logo.style.position = 'absolute';
            images.logo.style.left = 0;
            images.logo.style.top = 0;
            images.logo.style.right = 0;
            images.logo.style.bottom = '96px';
            images.logo.style.width = '256px';
            images.logo.style.height = '256px';
            images.logo.style.margin = 'auto';
            images.logo.style.MozUserSelect = 'none';
            images.logo.style.MSUserSelect = 'none';
            images.logo.style.OUserSelect = 'none';
            images.logo.style.WebkitUserSelect = 'none';
            images.loadingIcon = document.createElement('img');
            images.loadingIcon.setAttribute('id', 'loadingIcon');
            images.loadingIcon.style.position = 'absolute';
            images.loadingIcon.style.left = '16px';
            images.loadingIcon.style.top = '256px'
            images.loadingIcon.style.right = 0;
            images.loadingIcon.style.bottom = 0;
            images.loadingIcon.style.width = '32px';
            images.loadingIcon.style.height = '32px';
            images.loadingIcon.style.margin = 'auto';
            images.loadingIcon.style.MozUserSelect = 'none';
            images.loadingIcon.style.MSUserSelect = 'none';
            images.loadingIcon.style.OUserSelect = 'none';
            images.loadingIcon.style.WebkitUserSelect = 'none';
            images.loadingIcon.src = oxjsPath
                + '/UI/themes/' + theme + '/svg/symbolLoading.svg';
            callback(images);
        };
        images.logo.src = '/static/png/oml.png';
    }

    function loadOML(browserSupported) {
        window.oml = Ox.App({
            name: 'oml',
            socket: 'ws://' + document.location.host + '/ws',
            url: '/api/'
        }).bindEvent({
            load: function(data) {
                data.browserSupported = browserSupported;
                oml.ui = {};

                oml.ui.status = Ox.Element()
                    .css({
                        position: 'absolute',
                        left: 0,
                        right: 0,
                        bottom: '50px',
                        textAlign: 'center',
                        paddingLeft: '16px',
                        color: '#999999'
                    }).appendTo(Ox.$('#loadingScreen'));
                oml.ui.status.html('Updating Open Media Library...');
            },
            updatestatus: function(data) {
                oml.ui.status.html(data.status);
                oml.reload = data.reload;
            },
            close: function(data) {
            },
            open: function(data) {
                Ox.print('socket open');
                if (oml.reload) {
                    document.location.href = document.location.protocol + '//' + document.location.host;
                }
            }
        });
    }

    function loadOxJS(callback) {
        var head = document.head
                || document.getElementsByTagName('head')[0]
                || document.documentElement, 
            script = document.createElement('script');
        script.onload = function() {
            Ox.load({UI: {theme: theme}}, function() {
                Ox.formatUpper = function(string) {
                    return string.toUpperCase();
                };
                callback();
            });
        };
        script.src = oxjsPath + '/Ox.js?' + omlVersion;
        script.type = 'text/javascript';
        head.appendChild(script);
    }

    function loadScreen(images) {
        var loadingScreen = document.createElement('div');
        loadingScreen.setAttribute('id', 'loadingScreen');
        loadingScreen.className = 'OxScreen';
        loadingScreen.style.position = 'absolute';
        loadingScreen.style.width = '100%';
        loadingScreen.style.height = '100%';
        loadingScreen.style.backgroundColor = theme == 'oxlight' ? 'rgb(224, 224, 224)'
            : theme == 'oxmedium' ? 'rgb(144, 144, 144)' : 'rgb(32, 32, 32)';
        loadingScreen.style.zIndex = '1002';
        loadingScreen.appendChild(images.logo);
        loadingScreen.appendChild(images.loadingIcon);
        // FF3.6 document.body can be undefined here
        window.onload = function() {
            document.body.style.margin = 0;
            document.body.appendChild(loadingScreen);
            startAnimation();
        };
        // IE8 does not call onload if already loaded before set
        document.body && window.onload();
    }

    function removeScreen() {
        var $loadingScreen = $('#loadingScreen');
        $loadingScreen.animate({
            opacity: 0
        }, 1000, function() {
            $loadingScreen.remove();
        });
    }

    function startAnimation() {
        var css, deg = 0, loadingIcon = document.getElementById('loadingIcon'),
            previousTime = +new Date();
        animationInterval = setInterval(function() {
            var currentTime = +new Date(),
                delta = (currentTime - previousTime) / 1000;
            previousTime = currentTime;
            deg = Math.round((deg + delta * 360) % 360 / 30) * 30;
            css = 'rotate(' + deg + 'deg)';
            loadingIcon.style.MozTransform = css;
            loadingIcon.style.MSTransform = css;
            loadingIcon.style.OTransform = css;
            loadingIcon.style.WebkitTransform = css;
            loadingIcon.style.transform = css;
        }, 83);
    }

    function stopAnimation() {
        clearInterval(animationInterval);
    }

}());