All matches have their dates/details here:

http://www.fcbarcelona.com/football/first-team/calendar






Fifa dates:

2015
17 January - 07 February - Africa Cup of Nations 2015
23-31 March - Official or Friendly Matches
08-16 June - Official or Friendly Matches
11 June - 04 July - Copa America 2015
07-26 July - CONCACAF Gold Cup 2015


Barça players NT games this week(March 26th to 31st):

26/03:
France - Brazil
Iran - Chile

27/03:
Spain - Ukraine

28/03:
Croatia - Norway
El Salvador - Argentina

29/03:
Brazil - Chile

31/03:
Netherlands - Spain
Argentina - Ecuador