module.exports = Self => {
    Self.remoteMethodCtx('editLatestBuys', {
        description: 'Updates a column for one or more buys',
        accessType: 'WRITE',
        accepts: [{
            arg: 'field',
            type: 'string',
            required: true,
            description: `the column to edit`
        },
        {
            arg: 'newValue',
            type: 'any',
            required: true,
            description: `The new value to save`
        },
        {
            arg: 'lines',
            type: ['object'],
            required: true,
            description: `the buys which will be modified`
        },
        {
            arg: 'filter',
            type: 'object',
            description: 'Filter defining where, order, offset, and limit - must be a JSON-encoded string'
        }],
        returns: {
            type: 'object',
            root: true
        },
        http: {
            path: `/editLatestBuys`,
            verb: 'POST'
        }
    });

    Self.editLatestBuys = async(ctx, field, newValue, lines, filter, options) => {
        let tx;
        const myOptions = {};

        if (typeof options == 'object')
            Object.assign(myOptions, options);

        if (!myOptions.transaction) {
            tx = await Self.beginTransaction({});
            myOptions.transaction = tx;
        }

        let modelName;
        let identifier;

        switch (field) {
        case 'size':
        case 'weightByPiece':
        case 'description':
        case 'packingOut':
            modelName = 'Item';
            identifier = 'itemFk';
            break;
        case 'packing':
        case 'grouping':
        case 'groupingMode':
        case 'packageValue':
        case 'weight':
            modelName = 'Buy';
            identifier = 'id';
        }

        const models = Self.app.models;
        const model = models[modelName];
        try {
            const promises = [];
            const value = {};
            value[field] = newValue;

            if (filter) {
                ctx.args.filter = {where: filter, limit: null};
                lines = await models.Buy.latestBuysFilter(ctx, null, myOptions);
            }

            const targets = lines.map(line => {
                return line[identifier];
            });
            for (let target of targets)
                promises.push(model.upsertWithWhere({id: target}, value, myOptions));

            const result = await Promise.all(promises);

            if (tx) await tx.commit();

            return result;
        } catch (e) {
            if (tx) await tx.rollback();
            throw e;
        }
    };
};