CSV Product Data Analysis

This problem requires you to analyze product data provided in CSV format. The CSV input is read from standard input and contains the following columns:

• product_id
• category
• price
• quantity_sold
• rating

Your task is to compute and output a JSON object with four keys:

• total_products: the total number of product records.
• average_rating: the average rating computed as \(\text{average} = \frac{\text{sum of ratings}}{\text{total products}}\). If there are no products, the average rating is 0.
• highest_priced_product: an object representing the product with the highest price. This object should include product_id, category, price, quantity_sold, and rating. If no product exists, output an empty object.
• total_quantity_sold_per_category: an object that maps each category to the total quantity sold in that category.

Note: If the input only contains the header line (or is empty), your output must be:

{"total_products":0,"average_rating":0,"highest_priced_product":{},"total_quantity_sold_per_category":{}}

inputFormat

The input is provided through standard input (stdin) in CSV format. The first line is a header line:

product_id,category,price,quantity_sold,rating

Each subsequent line represents a product record with comma-separated values. You can assume that the input is well-formed, although it may be empty (apart from the header) which should be handled appropriately.

outputFormat

Output a single JSON object to standard output (stdout) with the following keys:

• total_products: An integer representing the total number of products.
• average_rating: A floating point number representing the average rating of the products.
• highest_priced_product: A JSON object representing the product with the highest price. It includes keys: product_id, category, price, quantity_sold, and rating. If no product exists, output an empty object.
• total_quantity_sold_per_category: A JSON object mapping each category to the sum of quantity_sold for that category.

## sample

product_id,category,price,quantity_sold,rating
1,Electronics,299.99,150,4.5
2,Books,19.99,1200,4.8
3,Clothing,49.99,500,4.2
4,Electronics,399.99,100,4.6

{"total_products":4,"average_rating":4.525,"highest_priced_product":{"product_id":4,"category":"Electronics","price":399.99,"quantity_sold":100,"rating":4.6},"total_quantity_sold_per_category":{"Electronics":250,"Books":1200,"Clothing":500}}