The trading function of the market.

trading_function_of_market.js

    this.trade = function(){
        var self = this;
        var sales = [];
 
        var productsInMarket = this.getProductsInMarket().values();
...
        //trade each product in succession
        _.each(productsInMarket, function(productId){
            var soldOutOfProduct = false;
            logger.debug('trading product ' + productId);
            var buyersInterestedInProduct = self.getBuyersInterestedInProduct(productId);
            if(buyersInterestedInProduct.length === 0){
                logger.info('no buyers interested in product ' + productId);
            }else{
                _.each(buyersInterestedInProduct, function(buyer){
                    if(!soldOutOfProduct){
                        logger.debug('  buyer ' + buyer.name + ' is searching for product ' + productId);
                        //select the cheapest seller
                        var cheapestSeller = _.chain(self.sellers)
                                              .filter(function(seller){return seller.hasProduct(productId);})
                                              .sortBy(function(seller){return seller.getCheapestSalesOrder(productId).price;})
                                              .first()
                                              .value();
 
                        if(cheapestSeller){
                            logger.debug('    cheapest seller is ' + cheapestSeller.name);
                            var newSales = self.createSale(buyer, cheapestSeller, productId);
                            sales = sales.concat(newSales);
                            logger.debug('    sales completed');
                        }else{
                            logger.warn('    market sold out of product ' + productId);
                            soldOutOfProduct = true;
                        }
                    }
                });
            }
        });
 
        return sales;
    };