salix/services/loopback/common/methods/sale/updateDiscount.js

let UserError = require('../../helpers').UserError;

module.exports = Self => {
    Self.remoteMethod('updateDiscount', {
        description: 'Changes the discount of a sale',
        accessType: '',
        accepts: [{
            arg: 'params',
            type: 'object',
            required: true,
            description: 'sale ID, newDiscount, price',
            http: {source: 'body'}
        }],
        returns: {
            type: 'string',
            root: true
        },
        http: {
            path: `/updateDiscount`,
            verb: 'post'
        }
    });

    Self.updateDiscount = async params => {
        if (isNaN(params.editLines[0].discount))
            throw new UserError(`The value should be a number`);

        let model = Self.app.models;
        let thisTicketIsEditable = await model.Ticket.isEditable(params.editLines[0].ticketFk);

        if (!thisTicketIsEditable)
            throw new UserError(`The sales of this ticket can't be modified`);

        let ticket = await model.Ticket.find({
            where: {
                id: params.editLines[0].ticketFk
            },
            include: [{
                relation: 'client',
                scope: {
                    fields: ['salesPersonFk']
                }
            }],
            fields: ['id', 'clientFk']
        });

        let componentToUse;
        let usesMana = await model.WorkerMana.findOne({where: {workerFk: ticket[0].client().salesPersonFk}, fields: 'amount'});

        if (usesMana)
            componentToUse = 37;
        else
            componentToUse = 34;

        for (let i = 0; i < params.editLines.length; i++) {
            let currentLine = await model.Sale.findOne({where: {id: params.editLines[i].id}, fields: 'price'});
            let value = ((-currentLine.price * params.editLines[i].discount) / 100);
            await model.SaleComponent.upsert({saleFk: params.editLines[i].id, value: value, componentFk: componentToUse});

            await model.Sale.update({id: params.editLines[i].id}, {discount: params.editLines[i].discount});
        }

        query = `
            call vn.manaSpellersRequery(?)`;
        await Self.rawSql(query, [ticket[0].client().salesPersonFk]);
    };
};