Script to automate download of data from a graph on a webpage that uses javascript

This is an academic research project. I want a script that downloads data from a graph from a website that uses javascript to populate the graph and requires authentication through login (which is free). The data I need is from a website called Appannie.com. This website provides ranking of mobile apps.I ant a script that given an appname should be able to get the complete rank history of the app across the categories displayed in the graph. Also, at the bottom axis of the graph it displays several bubble. If you take your mouse over the bubble it displays the info regarding any changes that were made to the app on any day. I want this information also. Here is an example. The following link provides the ranks for the app "angry-birds". [You will need to create a login at appannie (which is free) to access this info. http://www.appannie.com/apps/ios/app/angry-birds/rank-history/#start=2012-10-29&end=2013-10-28&view=rank&countries=US&vtype=day If you click on the date range it allows you to select the date range. Please select "All Time". This will then populate the graph with rankings for all time. You will see that it will display ranks for four different categories. I want all four ranks with time. And at the bottom there are several bubbles. I want information in those bubbles also. The deliverable for the project would be: 1. script that downloads the data given appname and the platform (ios, google-play, amazon, mac, windows-store) for " all time".. The data should be saved in excel, mysql, or a text/csv file. The script should be able to take a list of appname and the platform from a text file. 2. Instructions on how to use the script.