Help me, people!

When I started my computer this morning, I could not access ANY of my files. Their filenames are modified. .id-ksjudg89e_ extension was added to each file. I have found a Read me now !.txt file on my computer (on the desktop, to be precise). It says that absolutely all of my files are encrypted and that I must send a letter to two email addresses and also a message to a provided Bitmessage address to learn how to recover them. Can you tell me what’s going on and what happened to my computer? What kind of virus is JuicyLemon? I call it like that because one of the email addresses provided is support(@)juicylemon.com.