var Qs_Form = {
    message: new qs.Message({
        'eng': {
            'invalidInformationEntered': 'Please review the comments marked in red and make appropriate corrections.',
            'alertInvalidInformationEntered': 'Please make the following corrections:',
            'alertFromErrors': '',
            'pleaseCorrectTheseFields': ''
        }
    }),
    options: {
        elementsErrorsDisplayMethod: 'HTML',
        formErrorsDisplayMethod: 'HTML',
        errorAlertEnabled: true
    },

    formOptions: {},

    init: function (idForm, options)
    {
        var form = document.getElementById(idForm);
        if (!form) {
            alert('Form (id = ' + idForm + ') is not available');
            return false;
        }
        if (!form.tagName || form.tagName != 'FORM') {
            alert('Element (id = ' + idForm + ') is not a form - tagName = ' + form.tagName);
            return false;
        }

        if (options) {
            Qs_Form.formOptions[idForm] = options;
        }

        if (true == Qs_Form.getFormOption(idForm, 'errorAlertEnabled')
            && true == Qs_Form.getFormOption(idForm, 'isErrors')
        ) {
            Qs_Form.displayErrorsAlert();
            Qs_Form.setErrorFocus(form);
        }

        $(form).unbind('submit.form-plugin').bind('submit.form-plugin', Qs_Form.onSubmit);
        $(':submit,input:image', form).unbind('click.form-plugin').bind('click.form-plugin', Qs_Form.buttonOnClick);
    },

    buttonOnClick: function (e)
    {
        var form = this.form;
        form.clk = this;
        if (this.type == 'image') {
            if (e.offsetX != undefined) {
                form.clk_x = e.offsetX;
                form.clk_y = e.offsetY;
            } else if (typeof $.fn.offset == 'function') { /* try to use dimensions plugin */
                var offset = $(this).offset();
                form.clk_x = e.pageX - offset.left;
                form.clk_y = e.pageY - offset.top;
            } else {
                form.clk_x = e.pageX - this.offsetLeft;
                form.clk_y = e.pageY - this.offsetTop;
            }
        }
        setTimeout(function() {
            form.clk = form.clk_x = form.clk_y = null;
        }, 10);
    },

    getOption: function (name)
    {
        return Qs_Form.options[name];
    },

    setElementsErrorsDisplayMethod: function (idForm, value)
    {
        Qs_Form.setFormOption(idForm, 'elementsErrorsDisplayMethod', value);
    },

    getElementsErrorsDisplayMethod: function (idForm)
    {
        return Qs_Form.getFormOption(idForm, 'elementsErrorsDisplayMethod');
    },

    setFormErrorsDisplayMethod: function (idForm, value)
    {
        Qs_Form.setFormOption(idForm, 'formErrorsDisplayMethod', value);
    },

    getFormErrorsDisplayMethod: function (idForm)
    {
        return Qs_Form.getFormOption(idForm, 'formErrorsDisplayMethod');
    },

    setFormOption: function (idForm, name, value)
    {
        if (typeof Qs_Form.formOptions[idForm] == 'undefined') {
            Qs_Form.formOptions[idForm] = {};
        }
        Qs_Form.formOptions[idForm][name] = value;
    },

    getFormOption: function (idForm, name)
    {
        if (typeof Qs_Form.formOptions[idForm] == 'undefined' || typeof Qs_Form.formOptions[idForm][name] == 'undefined' ) {
            return Qs_Form.getOption(name);
        }
        return Qs_Form.formOptions[idForm][name];
    },

    onSubmitSuccess: function (response, form)
    {
        if (response.sessionExpired) {
            if (response.loginUrl) {
                qs.openPopupByLocation(response.loginUrl, 'qsPopup', 900, 400);
            }
            return true;
        }

        var id = $(form).attr('id');

        if (!_.isArray(response.formErrors)) {
            response.formErrors = [];
        }
        if (!_.isArray(response.elementsErrors)) {
            response.elementsErrors = [];
        }
        Qs_Form.setFormOption(id, 'response', response);

        if (response.isLocked) {
            alert(response.error);
        } else if (response.isValid && Qs_Form.isValidFiles(id)) {
            if (form) {
                var onSuccessCallback = Qs_Form.getFormOption($(form).attr('id'), 'onSuccessCallback');
                if (typeof onSuccessCallback == 'undefined') {
                    form.submit();
                } else {
                    qs.call(onSuccessCallback);
                }
            }
        } else {
            var onErrorCallback = Qs_Form.getFormOption($(form).attr('id'), 'onErrorCallback');
            if (typeof onErrorCallback != 'undefined') {
                qs.call(onErrorCallback);
                return true;
            }
            Qs_Form.displayErrors(id);
        }
        return response;
    },

    displayErrors: function (id)
    {
        var response = Qs_Form.getFormOption(id, 'response');

        if (!response.formErrors.length || response.elementsErrors.length) {
            response = Qs_Form.validateFiles(id, response);
        }

        var displayErrorsAlert = false;
        var form = document.getElementById(id);
        var elementsDisplayMethod = Qs_Form.getElementsErrorsDisplayMethod(id);
        var name, message, focusKey;

        if (response.formErrors.length) {
            var formDisplayMethod = Qs_Form.getFormErrorsDisplayMethod(id);
            switch (formDisplayMethod) {
                case 'ALERT':
                    Qs_Form.displayFromErrorsAlert(form, response.formErrors);
                    break;
                case 'HTML':
                    Qs_Form.displayFromErrorsHtml(form, response.formErrors);
                    displayErrorsAlert = true;
                    break;
                default:
                    alert('Qs_Form. Unknown formErrorsDisplayMethod "' + formDisplayMethod + '"');
            }
        }

        if (response.elementsErrors.length) {
            switch (elementsDisplayMethod) {
                case 'ALERT':
                    message = Qs_Form.message.get('alertInvalidInformationEntered') + "\n";
                    message += Qs_Form.prepareErrorsAlert(response.elementsErrors);
                    message += '\n\n' + Qs_Form.message.get('pleaseCorrectTheseFields');
                    alert(message);
                    break;
                case 'HTML':
                    Qs_Form.displayErrorsHtml(form, response.elementsErrors);
                    displayErrorsAlert = true;
                    break;
                default:
                    alert('Qs_Form. Unknown elementsErrorsDisplayMethod "' + elementsDisplayMethod + '"');
            }
        }

        if (displayErrorsAlert) {
            Qs_Form.displayErrorsAlert();
            Qs_Form.setErrorFocus(form);
        }

        if (response.elementsErrors.length) {
            for (var i in response.elementsErrors) {
                if (response.elementsErrors[i].type == 'captcha') {
                    var captchaElement = $('#' + response.elementsErrors[i].id + '-element');
                    if ($(captchaElement).size() != 0) {
                        var captchaData = response.elementsErrors[i].captcha;
                        var captchaId = response.elementsErrors[i].id;
                        $('img:first', captchaElement).attr('src', captchaData.src);
                        $('#' + captchaId + '-hidden', captchaElement).attr('value', captchaData.id);
                        $('#' + captchaId + '-input', captchaElement).attr('value', '');
                        $('#' + captchaId + '-input', captchaElement).blur();
                        if (typeof captchaData.href != 'undefined') {
                            $('a.captcha_refresh', captchaElement).attr('href', captchaData.href);
                        }
                    }
                }
            }
        }
    },

    setErrorFocus: function (form)
    {
        var id = $(form).attr('id');
        var response = Qs_Form.getFormOption(id, 'response');
        var focusKey = null;
        var scrollToKey = null;

        if (response.formErrors.length) {
            scrollToKey = id;
        } else if (response.elementsErrors.length) {
            var element = response.elementsErrors[0];

            if (0 == $('#' + element.id, form).size()) {
                // check if it is radio button
                var radio = $('#' + element.id + '-element input[id^+' + element.id + '][type=radio]', form).first();
                if ($(radio).size()) {
                    scrollToKey = element.id + '-label';
                }
            } else {
                if ($('#' + element.id, form).prop('focus')) {
                    focusKey = element.id;
                    scrollToKey = element.id + '-label';
                }
            }
        }

        if (focusKey && $('#' + focusKey + ':visible', form).size()) {
            $('#' + focusKey, form).focus();
        }

        if (scrollToKey && $('#' + scrollToKey + ':visible').size()) {
            $.scrollTo('#' + scrollToKey);
        }
    },

    displayFromErrorsAlert: function (form, errors)
    {
        var message = Qs_Form.message.get('alertFromErrors') + "\n";
        for (var i in errors) {
            message += '    - ' + errors[i] + '\n';
        }
        alert(message);
    },

    displayFromErrorsHtml: function (form, errors)
    {
        var html = '';
        for (var i in errors) {
            html += '<li>' + errors[i] + '</li>';
        }
        if (html != '') {
            html = '<ul class="errors">' + html + '</ul>';
            var formId = $(form).attr('id');
            $('#' + formId).prepend(html);
        }
    },

    getFirstName: function (errors, subitem)
    {
        var name =  _.keys(errors)[0];
        var result = name;
        if (typeof subitem != 'undefined' && subitem == true) {
            result = '[' + result + ']';
        }
        if (typeof errors[name] == 'object') {
            result += Qs_Form.getFirstName(errors[name], true);
        }
        if (typeof subitem == 'undefined') {
            var pos = result.lastIndexOf('[');
            if (pos > 0) {
                result = result.substring(0, pos);
            }
        }
        return result;
    },

    displayErrorsAlert: function ()
    {
        var message = Qs_Form.message.get('invalidInformationEntered') + '\n' + Qs_Form.message.get('pleaseCorrectTheseFields');
        alert(_.str.trim(message));
    },

    prepareErrorsAlert: function (elementsErrors)
    {
        var messages = '';
        for (var elementIndex in elementsErrors) {
            var message = '';
            for (var errorIndex in elementsErrors[elementIndex].errors) {
                message += '\n     - ' + elementsErrors[elementIndex].errors[errorIndex];
            }
            if (message != '') {
                messages += '\n' + elementsErrors[elementIndex].label + ':' + message;
            }
        }
        return messages;
    },

    displayErrorsHtml: function (form, elementsErrors)
    {
        for (var elementIndex in elementsErrors) {
            var html = '';
            for (var errorIndex in elementsErrors[elementIndex].errors) {
                html += '<li>' + elementsErrors[elementIndex].errors[errorIndex] + '</li>';
            }
            if (html != '') {
                html = '<ul class="errors">' + html + '</ul>';
                var idForm = $(form).attr('id');
                $('#' + elementsErrors[elementIndex].id + '-element').append(html);
            }
        }
    },

    isValidFiles: function(idForm)
    {
        var isValid = true;
        var files = Qs_Form.getFormOption(idForm, 'requiredFiles');
        if (_.isArray(files)) {
            var form = $('form#' + idForm);
            for (var i in files) {
                if ('' == _.str.trim($('input[type=file][name=' + files[i]['name'] + ']', form).val())) {
                    isValid = false;
                    break;
                }
            }
        }
        return isValid;
    },

    validateFiles: function (idForm, response)
    {
        var files = Qs_Form.getFormOption(idForm, 'requiredFiles');
        if (_.isArray(files)) {
            var form = $('form#' + idForm);
            if (typeof response.errors == 'undefined') {
                response.errors = {};
            }
            if (typeof response.elements == 'undefined') {
                response.elements = {};
            }
            for (var i in files) {
                var fileObj = $('input[type=file][name=' + files[i]['name'] + ']', form);
                if ('' == _.str.trim($(fileObj).val())) {
                    var error = {
                        'type'   : 'file',
                        'id'     : $(fileObj).attr('id'),
                        'label'  : files[i]['label'],
                        'errors' : {'isEmpty': "Value is required and can't be empty"}
                    };
                    response.isValid = false;
                    response.elementsErrors.push(error);
                }
            }
        }
        return response;
    },

    onSubmitError: function (request, textStatus, errorThrown)
    {
        alert(textStatus + ' ' + errorThrown);
    },

    onSubmitComplete: function (XMLHttpRequest, textStatus, form)
    {
        var idForm = $(form).attr('id');
        Qs_Form.formOptions[idForm]['processRequest'] = false;

        var onAfterSubmit = Qs_Form.getFormOption(idForm, 'onAfterSubmit');
        if (typeof onAfterSubmit != 'undefined') {
            qs.call(onAfterSubmit);
        }
    },

    removeElementsErrors: function (form)
    {
        $('ul.errors', form).remove();
    },

    editorsTriggerSave: function (form)
    {
        if (typeof tinyMCE != 'undefined') {
            tinyMCE.triggerSave();
        }

        if (typeof CKEDITOR != 'undefined') {
            for (var i = 0; i < form.elements.length; i++) {
                if (form.elements[i].tagName == 'TEXTAREA') {
                    if (typeof CKEDITOR.instances[form.elements[i].name] != 'undefined') {
                        if (CKEDITOR.instances[form.elements[i].name].checkDirty()) {
                            CKEDITOR.instances[form.elements[i].name].updateElement();
                        }
                    }
                }
            }
        }
    },

    releaseAutocompleteElements: function ()
    {
        if (typeof Qs_AutocompleteElement != 'undefined') {
            var instances = Qs_AutocompleteElement.getInstances();
            for (var i in instances) {
                instance = instances[i];
                instance.onChange(null, null);
            }
        }
    },

    onSubmit: function (spec)
    {
        var form;
        if (this.tagName == 'FORM') {
            form = this;
        } else {
            form = spec;
        }
        var idForm = $(form).attr('id');

        var onBeforeSubmit = Qs_Form.getFormOption(idForm, 'onBeforeSubmit');
        if (typeof onBeforeSubmit != 'undefined') {
            qs.call(onBeforeSubmit);
        }

        Qs_Form.editorsTriggerSave(form);
        Qs_Form.releaseAutocompleteElements();
        Qs_Form.removeElementsErrors(form);

        if (typeof Qs_Form.formOptions[idForm]['processRequest'] == 'undefined'
            || Qs_Form.formOptions[idForm]['processRequest'] != true
        ) {
            Qs_Form.formOptions[idForm]['processRequest'] = true;
            var deferred = qs.ajax($(form).attr('action'), Qs_Form.toObject(form), {
                type: String($(form).attr('method')).toUpperCase(),
                qsShowLoading: false,
                qsDefaultCallbacks: false
            });
            deferred.done(function (data) {
                Qs_Form.onSubmitSuccess(data, form);
            });
            deferred.fail(function (request, textStatus, errorThrown) {
                Qs_Form.onSubmitError(request, textStatus, errorThrown);
            });
            deferred.always(function (XMLHttpRequest, textStatus) {
                Qs_Form.onSubmitComplete(XMLHttpRequest, textStatus, form);
            });
        }
        return false;
    },

    getNormalizedName: function (name)
    {
        if (name.substring(name.length - 2) == '[]') {
            name = name.substr(0, name.length - 2);
        }
        return name;
    },

    setValue: function(/*Object*/obj, /*String*/name, /*String*/value)
    {
        var index = Qs_Form.getNormalizedName(name);
        var isMultiple = (name.substr(name.length - 2) == '[]');

        if (typeof obj[index] == 'undefined') {
            if (isMultiple) {
                obj[index] = [];
            } else {
                obj[index] = '';
            }
        }

        if (_.isArray(obj[index])) {
            obj[index].push(value);
        } else {
            obj[index] = value;
        }
    },

    toObject: function (/*DOMNode||String*/ formNode)
    {
        var ret = {};
        var exclude = 'file|submit|image|reset|button|';
        if (_.isString(formNode)) {
            formNode = document.getElementById(formNode);
        }
        for (var i = 0; i < formNode.elements.length; i++) {
            var item = formNode.elements[i];
            if (!item) {
                continue;
            }
            var _in = item.name;
            var type = (item.type || "").toLowerCase();
            if (_in && type && exclude.indexOf(type) == -1 && !item.disabled) {
                if (type == "radio" || type == 'checkbox') {
                    if (item.checked) {
                        Qs_Form.setValue(ret, _in, item.value);
                    }
                } else if (item.multiple) {
                    ret[Qs_Form.getNormalizedName(_in)] = [];
                    var nodes = [item.firstChild];
                    while (nodes.length) {
                        for (var node = nodes.pop(); node; node = node.nextSibling) {
                            if (node.nodeType == 1 && node.tagName.toLowerCase() == "option") {
                                if (node.selected ) {
                                    Qs_Form.setValue(ret, _in, node.value);
                                }
                            } else {
                                if (node.nextSibling) {
                                    nodes.push(node.nextSibling);
                                }
                                if (node.firstChild) {
                                    nodes.push(node.firstChild);
                                }
                                break;
                            }
                        }
                    }
                } else {
                    Qs_Form.setValue(ret, _in, item.value);
                    if (type == 'image') {
                        ret[_in+".x"] = ret[_in+".y"] = ret[_in].x = ret[_in].y = 0;
                    }
                }
            }
        }
        if (formNode.clk && !formNode.clk.disabled && formNode.clk.name) {
            if (formNode.clk.type == 'image') {
                ret[formNode.clk.name + '.x'] = formNode.clk_x;
                ret[formNode.clk.name + '.y'] = formNode.clk_y;
            } else {
                ret[formNode.clk.name] = formNode.clk.value;
            }
        }

        return ret; // Object
    }
};