function pos_screens(instance, module){ //module is instance.point_of_sale
    var QWeb = instance.web.qweb,
    _t = instance.web._t;

    var round_pr = instance.web.round_precision

    module.ClientListScreenWidget = module.ScreenWidget.extend({
        template: 'ClientListScreenWidget',

        init: function(parent, options){
            this._super(parent, options);
        },

        show_leftpane: false,

        auto_back: true,

        show: function(){
            var self = this;
            this._super();

            this.renderElement();
            this.details_visible = false;
            this.old_client = this.pos.get('selectedOrder').get('client');
            this.new_client = this.old_client;

            this.$('.back').click(function(){
                self.pos_widget.screen_selector.back();
            });

            this.$('.next').click(function(){
                self.save_changes();
                self.pos_widget.screen_selector.back();
            });

            this.$('.new-customer').click(function(){
                self.display_client_details('edit',{
                    'country_id': self.pos.company.country_id,
                });
            });

            var partners = this.pos.db.get_partners_sorted(1000);
            this.render_list(partners);

            this.reload_partners();

            if( this.old_client ){
                this.display_client_details('show',this.old_client,0);
            }

            this.$('.client-list-contents').delegate('.client-line','click',function(event){
                self.line_select(event,$(this),parseInt($(this).data('id')));
            });

            var search_timeout = null;

            if(this.pos.config.iface_vkeyboard && this.pos_widget.onscreen_keyboard){
                this.pos_widget.onscreen_keyboard.connect(this.$('.searchbox input'));
            }

            this.$('.searchbox input').on('keyup',function(event){
                clearTimeout(search_timeout);

                var query = this.value;

                search_timeout = setTimeout(function(){
                    self.perform_search(query,event.which === 13);
                },70);
            });

            this.$('.searchbox .search-clear').click(function(){
                self.clear_search();
            });
        },
        barcode_client_action: function(code){
            if (this.editing_client) {
                this.$('.detail.barcode').val(code.code);
            } else if (this.pos.db.get_partner_by_ean13(code.code)) {
                this.display_client_details('show',this.pos.db.get_partner_by_ean13(code.code));
            }
        },
        perform_search: function(query, associate_result){
            var customers;
            if(query){
                customers = this.pos.db.search_partner(query);
                this.display_client_details('hide');
                if ( associate_result && customers.length === 1){
                    this.new_client = customers[0];
                    this.save_changes();
                    this.pos_widget.screen_selector.back();
                }
                this.render_list(customers);
            }else{
                customers = this.pos.db.get_partners_sorted();
                this.render_list(customers);
            }
        },
        clear_search: function(){
            var customers = this.pos.db.get_partners_sorted(1000);
            this.render_list(customers);
            this.$('.searchbox input')[0].value = '';
            this.$('.searchbox input').focus();
        },
        render_list: function(partners){
            var contents = this.$el[0].querySelector('.client-list-contents');
            contents.innerHTML = "";
            for(var i = 0, len = Math.min(partners.length,1000); i < len; i++){
                var partner    = partners[i];
                var clientline_html = QWeb.render('ClientLine',{widget: this, partner:partners[i]});
                var clientline = document.createElement('tbody');
                clientline.innerHTML = clientline_html;
                clientline = clientline.childNodes[1];

                if( partners === this.new_client ){
                    clientline.classList.add('highlight');
                }else{
                    clientline.classList.remove('highlight');
                }

                contents.appendChild(clientline);
            }
        },
        save_changes: function(){
            if( this.has_client_changed() ){
                this.pos.get('selectedOrder').set_client(this.new_client);
            }
        },
        has_client_changed: function(){
            if( this.old_client && this.new_client ){
                return this.old_client.id !== this.new_client.id;
            }else{
                return !!this.old_client !== !!this.new_client;
            }
        },
        toggle_save_button: function(){
            var $button = this.$('.button.next');
            if (this.editing_client) {
                $button.addClass('oe_hidden');
                return;
            } else if( this.new_client ){
                if( !this.old_client){
                    $button.text(_t('Set Customer'));
                }else{
                    $button.text(_t('Change Customer'));
                }
            }else{
                $button.text(_t('Deselect Customer'));
            }
            $button.toggleClass('oe_hidden',!this.has_client_changed());
        },
        line_select: function(event,$line,id){
            var partner = this.pos.db.get_partner_by_id(id);
            this.$('.client-list .lowlight').removeClass('lowlight');
            if ( $line.hasClass('highlight') ){
                $line.removeClass('highlight');
                $line.addClass('lowlight');
                this.display_client_details('hide',partner);
                this.new_client = null;
                this.toggle_save_button();
            }else{
                this.$('.client-list .highlight').removeClass('highlight');
                $line.addClass('highlight');
                var y = event.pageY - $line.parent().offset().top
                this.display_client_details('show',partner,y);
                this.new_client = partner;
                this.toggle_save_button();
            }
        },
        partner_icon_url: function(id){
            return '/web/binary/image?model=res.partner&id='+id+'&field=image_small';
        },

        // ui handle for the 'edit selected customer' action
        edit_client_details: function(partner) {
            this.display_client_details('edit',partner);
        },

        // ui handle for the 'cancel customer edit changes' action
        undo_client_details: function(partner) {
            if (!partner.id) {
                this.display_client_details('hide');
            } else {
                this.display_client_details('show',partner);
            }
        },

        // what happens when we save the changes on the client edit form -> we fetch the fields, sanitize them,
        // send them to the backend for update, and call saved_client_details() when the server tells us the
        // save was successfull.
        save_client_details: function(partner) {
            var self = this;

            var fields = {}
            this.$('.client-details-contents .detail').each(function(idx,el){
                fields[el.name] = el.value;
            });

            if (!fields.name) {
                this.pos_widget.screen_selector.show_popup('error',{
                    message: _t('A Customer Name Is Required'),
                });
                return;
            }

            if (this.uploaded_picture) {
                fields.image = this.uploaded_picture;
            }

            fields.id           = partner.id || false;
            fields.country_id   = fields.country_id || false;
            fields.ean13        = fields.ean13 ? this.pos.barcode_reader.sanitize_ean(fields.ean13) : false;

            new instance.web.Model('res.partner').call('create_from_ui',[fields]).then(function(partner_id){
                self.saved_client_details(partner_id, fields);
            },function(err,event){
                event.preventDefault();
                self.pos_widget.screen_selector.show_popup('error',{
                    'message':_t('Error: Could not Save Changes'),
                    'comment':_t('Your Internet connection is probably down.'),
                });
            });
        },

        // what happens when we've just pushed modifications for a partner of id partner_id
        saved_client_details: function(partner_id, fields){
            var self = this;
            this.reload_partners().then(function(){
                var partner = self.pos.db.get_partner_by_id(partner_id);
                partner['ruc'] = fields.ruc;
                if (partner) {
                    self.new_client = partner;
                    self.toggle_save_button();
                    self.display_client_details('show',partner);
                } else {
                    // should never happen, because create_from_ui must return the id of the partner it
                    // has created, and reload_partner() must have loaded the newly created partner.
                    self.display_client_details('hide');
                }
            });
        },

        // resizes an image, keeping the aspect ratio intact,
        // the resize is useful to avoid sending 12Mpixels jpegs
        // over a wireless connection.
        resize_image_to_dataurl: function(img, maxwidth, maxheight, callback){
            img.onload = function(){
                var png = new Image();
                var canvas = document.createElement('canvas');
                var ctx    = canvas.getContext('2d');
                var ratio  = 1;

                if (img.width > maxwidth) {
                    ratio = maxwidth / img.width;
                }
                if (img.height * ratio > maxheight) {
                    ratio = maxheight / img.height;
                }
                var width  = Math.floor(img.width * ratio);
                var height = Math.floor(img.height * ratio);

                canvas.width  = width;
                canvas.height = height;
                ctx.drawImage(img,0,0,width,height);

                var dataurl = canvas.toDataURL();
                callback(dataurl);
            }
        },

        // Loads and resizes a File that contains an image.
        // callback gets a dataurl in case of success.
        load_image_file: function(file, callback){
            var self = this;
            if (!file.type.match(/image.*/)) {
                this.pos_widget.screen_selector.show_popup('error',{
                    message:_t('Unsupported File Format'),
                    comment:_t('Only web-compatible Image formats such as .png or .jpeg are supported'),
                });
                return;
            }

            var reader = new FileReader();
            reader.onload = function(event){
                var dataurl = event.target.result;
                var img     = new Image();
                img.src = dataurl;
                self.resize_image_to_dataurl(img,800,600,callback);
            }
            reader.onerror = function(){
                self.pos_widget.screen_selector.show_popup('error',{
                    message:_t('Could Not Read Image'),
                    comment:_t('The provided file could not be read due to an unknown error'),
                });
            };
            reader.readAsDataURL(file);
        },

        // This fetches partner changes on the server, and in case of changes,
        // rerenders the affected views
        reload_partners: function(){
            var self = this;
            return this.pos.load_new_partners().then(function(){
                self.render_list(self.pos.db.get_partners_sorted(1000));

                // update the currently assigned client if it has been changed in db.
                var curr_client = self.pos.get_order().get_client();
                if (curr_client) {
                    self.pos.get_order().set_client(self.pos.db.get_partner_by_id(curr_client.id));
                }
            });
        },

        // Shows,hides or edit the customer details box :
        // visibility: 'show', 'hide' or 'edit'
        // partner:    the partner object to show or edit
        // clickpos:   the height of the click on the list (in pixel), used
        //             to maintain consistent scroll.
        display_client_details: function(visibility,partner,clickpos){
            var self = this;
            var contents = this.$('.client-details-contents');
            var parent   = this.$('.client-list').parent();
            var scroll   = parent.scrollTop();
            var height   = contents.height();

            contents.off('click','.button.edit');
            contents.off('click','.button.save');
            contents.off('click','.button.undo');
            contents.on('click','.button.edit',function(){ self.edit_client_details(partner); });
            contents.on('click','.button.save',function(){ self.save_client_details(partner); });
            contents.on('click','.button.undo',function(){ self.undo_client_details(partner); });
            this.editing_client = false;
            this.uploaded_picture = null;

            if(visibility === 'show'){
                contents.empty();
                contents.append($(QWeb.render('ClientDetails',{widget:this,partner:partner})));

                var new_height   = contents.height();

                if(!this.details_visible){
                    if(clickpos < scroll + new_height + 20 ){
                        parent.scrollTop( clickpos - 20 );
                    }else{
                        parent.scrollTop(parent.scrollTop() + new_height);
                    }
                }else{
                    parent.scrollTop(parent.scrollTop() - height + new_height);
                }

                this.details_visible = true;
                this.toggle_save_button();
            } else if (visibility === 'edit') {
                this.editing_client = true;
                contents.empty();
                contents.append($(QWeb.render('ClientDetailsEdit',{widget:this,partner:partner})));
                this.toggle_save_button();

                contents.find('.image-uploader').on('change',function(event){
                    self.load_image_file(event.target.files[0],function(res){
                        if (res) {
                            contents.find('.client-picture img, .client-picture .fa').remove();
                            contents.find('.client-picture').append("<img src='"+res+"'>");
                            contents.find('.detail.picture').remove();
                            self.uploaded_picture = res;
                        }
                    });
                });
            } else if (visibility === 'hide') {
                contents.empty();
                if( height > scroll ){
                    contents.css({height:height+'px'});
                    contents.animate({height:0},400,function(){
                        contents.css({height:''});
                    });
                }else{
                    parent.scrollTop( parent.scrollTop() - height);
                }
                this.details_visible = false;
                this.toggle_save_button();
            }
        },
        close: function(){
            this._super();
        },
    });

    module.ReceiptScreenWidget = module.ScreenWidget.extend({
        template: 'ReceiptScreenWidget',

        show_numpad:     false,
        show_leftpane:   false,

        show: function(){
            this._super();
            var self = this;

            var print_button = this.add_action_button({
                    label: _t('Print'),
                    icon: '/point_of_sale/static/src/img/icons/png48/printer.png',
                    click: function(){ self.print(); },
                });

            var finish_button = this.add_action_button({
                    label: _t('Next Order'),
                    icon: '/point_of_sale/static/src/img/icons/png48/go-next.png',
                    click: function() { self.finishOrder(); },
                });

            this.refresh();

            finish_button.set_disabled(true);
            setTimeout(function(){
                finish_button.set_disabled(false);
            }, 2000);
        },
        print: function() {
            this.pos.get('selectedOrder')._printed = true;
            window.print();
        },
        finishOrder: function() {
            this.pos.get('selectedOrder').destroy();
        },
        refresh: function() {
            var order = this.pos.get('selectedOrder');
            $('.pos-receipt-container', this.$el).html(QWeb.render('PosTicket',{
                widget:this,
                order: order,
                orderlines: order.get('orderLines').models,
                paymentlines: order.get('paymentLines').models,
                logo: order.pos.company_logo_base64
            }));
        },
        close: function(){
            this._super();
        }
    });

}