class OnlineShop {
   constructor(warehouseSpace) {
     this.warehouseSpace = warehouseSpace;
     this.products = [];
     this.sales = [];
   }

   loadingStore(product, quantity, spaceRequired) {
     if (this.warehouseSpace < spaceRequired) {
       throw new Error('Not enough space in the warehouse.');
     }
     this.products.push({
       product,
       quantity,
     });

     this.warehouseSpace -= spaceRequired;
     return `The ${product} has been successfully delivered in the warehouse.`;
   }

   quantityCheck(product, minimalQuantity) {
     const currentProduct = this.products.find((p) => p.product === product);
     if (currentProduct === undefined) {
       throw new Error(`There is no ${product} in the warehouse.`);
     }
     if (minimalQuantity <= 0) {
       throw new Error('The quantity cannot be zero or negative.');
     }
     if (currentProduct.quantity >= minimalQuantity) {
       return `You have enough from product ${product}.`;
     }

     const diff = minimalQuantity - currentProduct.quantity;
     currentProduct.quantity = minimalQuantity;
     return `You added ${diff} more from the ${product} products.`;
   }

   sellProduct(product) {
     const currentProduct = this.products.find((p) => p.product === product);
     if (currentProduct === undefined) {
       throw new Error(`There is no ${product} in the warehouse.`);
     }

     currentProduct.quantity--;

     this.sales.push({
       product,
       quantity: 1,
     });

     return `The ${product} has been successfully sold.`;
   }

   revision() {
     if (!this.sales.length) {
       throw new Error('There are no sales today!');
     }

     const salesCount = this.sales.reduce((acc, x) => acc.quantity + x.quantity);
     const res = [`You sold ${salesCount} products today!`];
     res.push('Products in the warehouse:');

     this.products.forEach((p) =>
       res.push(`${p.product}-${p.quantity} more left`)
     );

     return res.join('\n');
   }
 }