Changing Calendar Plugin

Hi.
I need to make changes to the date plugin in a modern format. Please advise how I can do this or change this plugin altogether

What plugin? There's no plugin.

I need to change datepicker at reports for selecting date in another calendar format (Hijri/Shamsi) and replace that with gregorian date format

I believe that's the standard browser date picker there.

it's true. But is this datepicker created with JavaScript or from the server side and by Java? Because I really need to have solar date in Farsi language mode

The field is added by JavaScript, if that's what you're asking.

where I can change that in main276d165c.js. I unminified this file and need to change particular part about datepicker

You should download the proper source code and edit it there.

thanks, I will work on main276d165c.js and change the code about calendar