pos/pos_tare_generate_barcode/static/src/js/screens.js

odoo.define('pos_barcode_tare.screens', function (require) {

    "use strict";
    var core = require('web.core');
    var gui = require('point_of_sale.gui');
    var models = require('point_of_sale.models');
    var screens = require('point_of_sale.screens');
    var tools = require('pos_tare.tools');

    var QWeb = core.qweb;
    var _t = core._t;
    var convert_mass = tools.convert_mass;
    var format_tare = tools.format_tare;

    // This create a new button on top of action widget. This button links to
    // the barcode label printing screen defined below.
    var TareScreenButton = screens.ActionButtonWidget.extend({
        template: 'TareScreenButton',

        button_click: function () {
            this.gui.show_screen('tare');
        },
    });

    screens.define_action_button({
        'name': 'tareScreenButton',
        'widget': TareScreenButton,
    });

    // This is a new screen that reads weight from the electronic scale and
    // create a barcode label encoding the weight. The screen shows a preview
    // of the label. The user is expected to check if the preview matches what's
    // measured on the scale. The barcode image is generated by the report
    // module.
    var TareScreenWidget = screens.ScreenWidget.extend({
        template: 'TareScreenWidget',
        next_screen: 'products',
        previous_screen: 'products',
        default_tare_value: 0.0,
        weight_barcode_prefix: null,

        show: function () {
            this._super();
            // Fetch the barcode prefix from POS barcode parser rules.
            this.weight_barcode_prefix = this.get_barcode_prefix();
            // Setup the proxy
            var queue = this.pos.proxy_queue;
            // The pooling of the scale starts here.
            var self = this;
            queue.schedule(function () {
                return self.pos.proxy.scale_read().then(function (weight) {
                    try {
                        self.set_tare_weight(weight);
                    } catch (error) {
                        var title = _t("Failed to read weight from scale.");
                        var popup = {title: title, body: error.message};
                        self.gui.show_popup('error', popup);
                    }
                });
            }, {duration:150, repeat: true});
            // Shows a barcode whose weight might be zero, but this is preferred
            // for UI/UX reasons.
            this.render_receipt();
            this.lock_screen(true);
        },
        get_barcode_prefix: function () {
            var barcode_pattern = this.get_barcode_pattern();
            return barcode_pattern.substr(0, 2);
        },
        get_barcode_pattern: function () {
            var rules = this.get_barcode_rules();
            var rule = rules.filter(
                function (r) {
                    // We select the first (smallest sequence ID) barcode rule
                    // with the expected type.
                    return r.type === "tare";
                })[0];
            return rule.pattern;
        },
        get_barcode_rules: function () {
            return this.pos.barcode_reader.barcode_parser.nomenclature.rules;
        },
        set_tare_weight: function (scale_measure) {
            var weight = scale_measure.weight;
            var measure_unit = this.pos.units.filter(
                function (u) {
                    return u.name === scale_measure.unit;
                })[0];

            if (typeof measure_unit === 'undefined') {
                throw new Error(_.str.sprintf(
                    _t("The scale sent a measure in %s unit. This unit of "+
                     "measure (UOM) in not found in the point of sale. You " +
                     "may need to create a new UOM named %s. The UOM name is "+
                     "case sensitive."), scale_measure.unit,
                    scale_measure.unit));
            }

            if (weight > 0) {
                var tare_uom = this.pos.config.iface_tare_uom_id[0];
                var tare_unit = this.pos.units_by_id[tare_uom];
                this.weight_in_tare_unit = convert_mass(weight,
                    measure_unit, tare_unit);
                this.render_receipt();
                this.lock_screen(false);
            }
        },
        get_tare_weight: function () {
            if (typeof this.weight_in_tare_unit === 'undefined') {
                return this.default_tare_value;
            }
            return this.weight_in_tare_unit;
        },
        barcode_data: function (weight) {
            // We use EAN13 barcode, it looks like 07 00000 12345 x. First there
            // is the prefix, here 07, that is used to decide which type of
            // barcode we're dealing with. A weight barcode has then two groups
            // of five digits. The first group encodes the product id. Here the
            // product id is 00000. The second group encodes the weight in
            // grams. Here the weight is 12.345kg. The last digit of the barcode
            // is a checksum, here symbolized by x.
            var padding_size = 5;
            var void_product_id = '0'.repeat(padding_size);
            var weight_in_gram = weight * 1e3;

            if (weight_in_gram >= Math.pow(10, padding_size)) {
                throw new RangeError(_t("Maximum tare weight is 99.999kg"));
            }

            // Weight has to be padded with zeros.
            var weight_with_padding = '0'.repeat(padding_size) + weight_in_gram;
            var padded_weight = weight_with_padding.substr(
                weight_with_padding.length - padding_size);
            // Builds the barcode using a placeholder checksum.
            var barcode = this.weight_barcode_prefix
                .concat(void_product_id, padded_weight)
                .concat(0);
            // Compute checksum
            var barcode_parser = this.pos.barcode_reader.barcode_parser;
            var checksum = barcode_parser.ean_checksum(barcode);
            // Replace checksum placeholder by the actual checksum.
            return barcode.substr(0, 12).concat(checksum);
        },
        get_barcode_data: function () {
            return this.barcode_data(this.get_tare_weight());
        },
        lock_screen: function (locked) {
            this._locked = locked;
            if (locked) {
                this.$('.print-label').addClass('disabled');
            } else {
                this.$('.print-label').removeClass('disabled');
            }
        },
        print_web: function () {
            window.print();
            this.pos.get_order()._printed = true;
        },
        print: function () {
            // See comment in print function of ReceiptScreenWidget
            this.lock_screen(true);
            var self = this;
            setTimeout(function () {
                self.lock_screen(false);
            }, 1000);

            this.print_web();
            this.click_back();
        },
        click_back: function () {
            this.close();
            this.gui.show_screen(this.previous_screen);
        },
        renderElement: function () {
            this._super();
            var self = this;
            this.$('.back').click(function () {
                self.click_back();
            });
            this.$('.print-label').click(function () {
                if (!self._locked) {
                    self.print();
                }
            });
        },
        render_receipt: function () {
            this.$('.pos-tare-label-container').html(
                QWeb.render('PosTareLabel', {widget:this}));
        },
        close: function () {
            this._super();
            delete this.weight;
            this.pos.proxy_queue.clear();
        },
    });

    gui.define_screen({name:'tare', widget: TareScreenWidget});

});