let UserError = require('vn-loopback/util/user-error');

module.exports = Self => {
    Self.remoteMethodCtx('confirm', {
        description: '',
        accessType: 'WRITE',
        accepts: [{
            arg: 'id',
            type: 'Integer',
            required: true,
            description: 'The request ID',
        }, {
            arg: 'itemFk',
            type: 'Integer',
            required: true,
            description: 'The requested item ID',
        }, {
            arg: 'quantity',
            type: 'Integer',
            required: true,
            description: 'The requested item quantity',
        }],
        returns: {
            type: 'Object',
            root: true
        },
        http: {
            path: `/:id/confirm`,
            verb: 'post'
        }
    });

    Self.confirm = async ctx => {
        const models = Self.app.models;
        let sale;
        let tx = await Self.beginTransaction({});

        try {
            let options = {transaction: tx};

            let item = await models.Item.findById(ctx.args.itemFk, null, options);
            if (!item)
                throw new UserError(`That item doesn't exists`);

            let request = await models.TicketRequest.findById(ctx.args.id, {
                include: {relation: 'ticket'}
            }, options);

            let [[stock]] = await Self.rawSql(`CALL vn.item_getVisibleAvailable(?,?,?,?)`, [
                ctx.args.itemFk,
                request.ticket().shipped,
                request.ticket().warehouseFk,
                false
            ], options);

            if (stock.available < 0)
                throw new UserError(`This item is not available`);


            if (request.saleFk) {
                sale = await models.Sale.findById(request.saleFk, null, options);
                sale.updateAttributes({
                    itemFk: ctx.args.itemFk,
                    quantity: ctx.args.quantity,
                    concept: item.name,
                }, options);
            } else {
                sale = await models.Sale.create({
                    ticketFk: request.ticketFk,
                    itemFk: ctx.args.itemFk,
                    quantity: ctx.args.quantity,
                    concept: item.name
                }, options);
                request.updateAttributes({
                    saleFk: sale.id,
                    itemFk: sale.itemFk,
                    isOk: true
                }, options);
            }

            query = `CALL vn.ticketCalculateSale(?)`;
            await Self.rawSql(query, [sale.id], options);

            const message = `Se ha comprado ${sale.quantity} unidades de "${sale.concept}" (#${sale.itemFk}) `
                + `para el ticket #${sale.ticketFk}`;

            await models.Message.send(ctx, {
                recipientFk: request.requesterFk,
                message: message
            }, options);

            await tx.commit();

            return sale;
        } catch (error) {
            await tx.rollback();
            throw error;
        }
    };
};