Firebird query make row as column on 2 table

hi,pls help me, i will try to explain what i want to achieve

table A
id namelocation
0 warehouse 1
1 warehouse 2

table B
id nameproduct qty location
0 keyboard 2 warehouse 1
1 Mouse 5 warehouse 2


query result
nameproduct warehouse 1 warehouse 2
keyboard 2 0
mouse 0 5

how can i query that? the row on table a is not limited only two,so i try to dynamically generate column base on table a row


thx