I need a PC or Mac application that will...

I need a program that will scrape any link that is submitted to a input. After I submit the link I will need the program to allow me to select an element on that page using Class, id or xpath (if needed). And put contents of that element in the database. Next time when we scrape the data again from the same website and select the same element, we compare the element content with the content stored in the database to see if anything has been modified since last time. If modifications has been found I will need it to tweet out the changes. Example: Let’s say we craping a sneaker website for looking for shoe to restock. Once the app finds a change on the page it will tweet in this format: Adidas Ultra Boost Olympic Size 9 http://… The program should have a menu or option where I can input the credentials of the twitter account I will like to use for tweeting purpose.